Common ARM support

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@187 42af7a65-404d-4744-a932-0658087f49c3

32 files changed, 4495 insertions, 0 deletions

diff --git a/nuttx/arch/arm/src/common/arm.h b/nuttx/arch/arm/src/common/arm.h
new file mode 100644
index 000000000..8f3597813
--- /dev/null
+++ b/nuttx/arch/arm/src/common/arm.h
@@ -0,0 +1,254 @@
+/************************************************************************************
+ * common/arm.h
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************************************/
+
+#ifndef __ARM_H
+#define __ARM_H
+
+/************************************************************************************
+ * Included Files
+ ************************************************************************************/
+
+#ifndef __ASSEMBLY__
+# include <sys/types.h>
+#endif
+
+/**************************************************************************
+ * Conditional Compilation
+ **************************************************************************/
+
+#undef CONFIG_ALIGNMENT_TRAP
+#undef CONFIG_DCACHE_WRITETHROUGH
+#undef CONFIG_CACHE_ROUND_ROBIN
+#undef CONFIG_DCACHE_DISABLE
+#undef CONFIG_ICACHE_DISABLE
+
+/************************************************************************************
+ * Definitions
+ ************************************************************************************/
+
+/* ARM9EJS **************************************************************************/
+
+/* PSR bits */
+
+#define MODE_MASK       0x0000001f
+#define USR26_MODE      0x00000000
+#define FIQ26_MODE      0x00000001
+#define IRQ26_MODE      0x00000002
+#define SVC26_MODE      0x00000003
+#define USR_MODE        0x00000010
+#define FIQ_MODE        0x00000011
+#define IRQ_MODE        0x00000012
+#define SVC_MODE        0x00000013
+#define ABT_MODE        0x00000017
+#define UND_MODE        0x0000001b
+#define MODE32_BIT      0x00000010
+#define SYSTEM_MODE     0x0000001f
+#define PSR_T_BIT       0x00000020
+#define PSR_F_BIT       0x00000040
+#define PSR_I_BIT       0x00000080
+#define PSR_J_BIT       0x01000000
+#define PSR_Q_BIT       0x08000000
+#define PSR_V_BIT       0x10000000
+#define PSR_C_BIT       0x20000000
+#define PSR_Z_BIT       0x40000000
+#define PSR_N_BIT       0x80000000
+
+/* CR1 bits (CP#15 CR1) */
+
+#define CR_M            0x00000001 /* MMU enable                          */
+#define CR_A            0x00000002 /* Alignment abort enable              */
+#define CR_C            0x00000004 /* Dcache enable                       */
+#define CR_W            0x00000008 /* Write buffer enable                 */
+#define CR_P            0x00000010 /* 32-bit exception handler            */
+#define CR_D            0x00000020 /* 32-bit data address range           */
+#define CR_L            0x00000040 /* Implementation defined              */
+#define CR_B            0x00000080 /* Big endian                          */
+#define CR_S            0x00000100 /* System MMU protection               */
+#define CR_R            0x00000200 /* ROM MMU protection                  */
+#define CR_F            0x00000400 /* Implementation defined              */
+#define CR_Z            0x00000800 /* Implementation defined              */
+#define CR_I            0x00001000 /* Icache enable                       */
+#define CR_V            0x00002000 /* Vectors relocated to 0xffff0000     */
+#define CR_RR           0x00004000 /* Round Robin cache replacement       */
+#define CR_L4           0x00008000 /* LDR pc can set T bit                */
+#define CR_DT           0x00010000
+#define CR_IT           0x00040000
+#define CR_ST           0x00080000
+#define CR_FI           0x00200000 /* Fast interrupt (lower latency mode) */
+#define CR_U            0x00400000 /* Unaligned access operation          */
+#define CR_XP           0x00800000 /* Extended page tables                */
+#define CR_VE           0x01000000 /* Vectored interrupts                 */
+
+/* Hardware page table definitions.
+ *
+ * Level 1 Descriptor (PMD)
+ *
+ * Common definitions.
+ */
+
+#define PMD_TYPE_MASK       0x00000003  /* Bits 1:0:   Type of descriptor */
+#define PMD_TYPE_FAULT      0x00000000
+#define PMD_TYPE_COARSE     0x00000001
+#define PMD_TYPE_SECT       0x00000002
+#define PMD_TYPE_FINE       0x00000003
+                                    /* Bits 3:2:   Depends on descriptor */
+#define PMD_BIT4            0x00000010  /* Bit  4:     Must be one */
+#define PMD_DOMAIN_MASK     0x000001e0  /* Bits 8:5:   Domain control bits */
+#define PMD_DOMAIN(x)       ((x) << 5)
+#define PMD_PROTECTION      0x00000200  /* Bit 9:      v5 only */
+                                    /* Bits 31:10: Depend on descriptor */
+
+/* Level 1 Section Descriptor.  Section descriptors allow fast, single
+ * level mapping between 1Mb address regions.
+ */
+                                        /* Bits 1:0:   Type of mapping */
+#define PMD_SECT_BUFFERABLE 0x00000004  /* Bit  2:     1=bufferable */
+#define PMD_SECT_CACHEABLE  0x00000008  /* Bit  3:     1=cacheable */
+                                        /* Bit  4:     Common, must be one */
+                                        /* Bits 8:5:   Common domain control */
+                                        /* Bit  9:     Common protection */
+#define PMD_SECT_AP_MASK    0x00000c00  /* Bits 11:10: Access permission */
+#define PMD_SECT_AP_WRITE   0x00000400
+#define PMD_SECT_AP_READ    0x00000800
+                                        /* Bits 19:20: Should be zero */
+#define PMD_SECT_TEX_MASK   0xfff00000  /* Bits 31:20: v5, Physical page */
+#define PMD_SECT_APX        0x00008000  /* Bit  15:    v6 only */
+#define PMD_SECT_S          0x00010000  /* Bit  16:    v6 only */
+#define PMD_SECT_nG         0x00020000  /* Bit  17:    v6 only */
+
+#define PMD_SECT_UNCACHED   (0)
+#define PMD_SECT_BUFFERED   (PMD_SECT_BUFFERABLE)
+#define PMD_SECT_WT         (PMD_SECT_CACHEABLE)
+#define PMD_SECT_WB         (PMD_SECT_CACHEABLE|PMD_SECT_BUFFERABLE)
+#define PMD_SECT_MINICACHE  (PMD_SECT_TEX(1)|PMD_SECT_CACHEABLE)
+#define PMD_SECT_WBWA       (PMD_SECT_TEX(1)|PMD_SECT_CACHEABLE|PMD_SECT_BUFFERABLE)
+
+/* Level 1 Coarse Table Descriptor.  Coarse Table Descriptors support
+ * two level mapping between 16Kb memory regions.
+ */
+                                        /* Bits 1:0:   Type of mapping */
+                                        /* Bits 3:2:   Should be zero */
+                                        /* Bit  4:     Common, must be one */
+                                        /* Bits 8:5:   Common domain control */
+                                        /* Bits 9:     Should be zero */
+#define PMD_COARSE_TEX_MASK 0xfffffc00  /* Bits 31:10: v5, Physical page */
+
+/* Level 1 Fine Table Descriptor.  Coarse Table Descriptors support
+ * two level mapping between 4Kb memory regions.
+ */
+
+                                        /* Bits 1:0:   Type of mapping */
+                                        /* Bits 3:2:   Should be zero */
+                                        /* Bit  4:     Common, must be one */
+                                        /* Bits 8:5:   Common domain control */
+                                        /* Bits 11:9:  Should be zero */
+#define PMD_FINE_TEX_MASK   0xfffff000  /* Bits 31:12: v5, Physical page */
+
+/* Level 2 Table Descriptor (PTE).  -- All tables */
+
+#define PTE_TYPE_MASK       (3 << 0)    /* Bits: 1:0:  Type of mapping */
+#define PTE_TYPE_FAULT      (0 << 0)    /*   None */
+#define PTE_TYPE_LARGE      (1 << 0)    /*   64Kb of memory */
+#define PTE_TYPE_SMALL      (2 << 0)    /*    4Kb of memory */
+#define PTE_TYPE_TINY       (3 << 0)    /*    1Kb of memory (v5)*/
+#define PTE_BUFFERABLE      (1 << 2)    /* Bit  2:     1=bufferable */
+#define PTE_CACHEABLE       (1 << 3)    /* Bit  3:     1=cacheable */
+                                        /* Bits 31:4:  Depend on type */
+
+/* Large page -- 64Kb */
+                                         /* Bits: 1:0:  Type of mapping */
+                                         /* Bits: 3:2:  Bufferable/cacheable */
+#define PTE_LARGE_AP_MASK    (0xff << 4) /* Bits 11:4   Access permissions */
+#define PTE_LARGE_AP_UNO_SRO (0x00 << 4)
+#define PTE_LARGE_AP_UNO_SRW (0x55 << 4)
+#define PTE_LARGE_AP_URO_SRW (0xaa << 4)
+#define PTE_LARGE_AP_URW_SRW (0xff << 4)
+                                         /* Bits 15:12: Should be zero */
+#define PTE_LARGE_TEX_MASK   0xffff0000  /* Bits 31:16: v5, Physical page */
+
+/* Small page -- 4Kb */
+
+                                         /* Bits: 1:0:  Type of mapping */
+                                         /* Bits: 3:2:  Bufferable/cacheable */
+#define PTE_SMALL_AP_MASK    (0xff << 4) /* Bits: 11:4: Access permissions */
+#define PTE_SMALL_AP_UNO_SRO (0x00 << 4)
+#define PTE_SMALL_AP_UNO_SRW (0x55 << 4)
+#define PTE_SMALL_AP_URO_SRW (0xaa << 4)
+#define PTE_SMALL_AP_URW_SRW (0xff << 4)
+#define PTE_SMALL_TEX_MASK   0xfffff000  /* Bits: 31:12: Physical page */
+
+/* Tiny page -- 1Kb */
+
+                                        /* Bits: 1:0:  Type of mapping */
+                                        /* Bits: 3:2:  Bufferable/cacheable */
+#define PTE_EXT_AP_MASK      (3 << 4)   /* Bits: 5:4:  Access persions */
+#define PTE_EXT_AP_UNO_SRO   (0 << 4)
+#define PTE_EXT_AP_UNO_SRW   (1 << 4)
+#define PTE_EXT_AP_URO_SRW   (2 << 4)
+#define PTE_EXT_AP_URW_SRW   (3 << 4)
+                                        /* Bits: 9:6:  Should be zero */
+#define PTE_TINY_TEX_MASK    0xfffffc00 /* Bits: 31:10: Physical page */
+
+/* Default MMU flags for memory and IO */
+
+#define MMU_MEMFLAGS \
+  (PMD_TYPE_SECT|PMD_SECT_WB|PMD_BIT4|PMD_SECT_AP_WRITE|PMD_SECT_AP_READ)
+
+#define MMU_IOFLAGS \
+  (PMD_TYPE_SECT|PMD_BIT4|PMD_SECT_AP_WRITE|PMD_SECT_AP_READ)
+
+#define MMU_L1_VECTORFLAGS   (PMD_TYPE_COARSE|PMD_BIT4)
+#define MMU_L2_VECTORFLAGS   (PTE_TYPE_SMALL|PTE_SMALL_AP_UNO_SRW)
+
+/* Mapped section size */
+
+#define SECTION_SIZE          (1 << 20)   /* 1Mb */
+
+/* We place the page tables 16K below the beginning of .text.  The
+ * following value is assume to be the (virtual) start address of
+ * .text.
+ */
+
+#define PGTABLE_SIZE          0x00004000
+
+/************************************************************************************
+ * Inline Functions
+ ************************************************************************************/
+
+#ifndef __ASSEMBLY__
+
+#endif
+
+#endif  /* __ARM_H */
diff --git a/nuttx/arch/arm/src/common/up_allocateheap.c b/nuttx/arch/arm/src/common/up_allocateheap.c
new file mode 100644
index 000000000..8e8f6b169
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_allocateheap.c
@@ -0,0 +1,79 @@
+/************************************************************
+ * common/up_allocateheap.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "up_arch.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_allocate_heap
+ *
+ * Description:
+ *   The heap may be statically allocated by
+ *   defining CONFIG_HEAP_BASE and CONFIG_HEAP_SIZE.  If these
+ *   are not defined, then this function will be called to
+ *   dynamically set aside the heap region.
+ *
+ ************************************************************/
+
+void up_allocate_heap(FAR void **heap_start, size_t *heap_size)
+{
+  up_ledon(LED_HEAPALLOCATE);
+  *heap_start = (FAR void*)g_heapbase;
+  *heap_size = CONFIG_DRAM_END - g_heapbase;
+}
diff --git a/nuttx/arch/arm/src/common/up_arch.h b/nuttx/arch/arm/src/common/up_arch.h
new file mode 100644
index 000000000..071e60d67
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_arch.h
@@ -0,0 +1,92 @@
+/************************************************************************************
+ * common/up_arch.h
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************************************/
+
+#ifndef __UP_ARCH_H
+#define __UP_ARCH_H
+
+/************************************************************************************
+ * Included Files
+ ************************************************************************************/
+
+#include <nuttx/config.h>
+#ifndef __ASSEMBLY__
+# include <sys/types.h>
+#endif
+
+#include "arm.h"
+#include <arch/board/board.h>
+#include "chip.h"
+
+/************************************************************************************
+ * Definitions
+ ************************************************************************************/
+
+/************************************************************************************
+ * Inline Functions
+ ************************************************************************************/
+
+#ifndef __ASSEMBLY__
+
+# define getreg8(a)           (*(volatile ubyte *)(a))
+# define putreg8(v,a)         (*(volatile ubyte *)(a) = (v))
+# define getreg32(a)          (*(volatile uint32 *)(a))
+# define putreg32(v,a)        (*(volatile uint32 *)(a) = (v))
+
+/* Some compiler options will convert short loads and stores into byte loads
+ * and stores.  We don't want this to happen for IO reads and writes!
+ */
+
+/* # define getreg16(a)       (*(volatile uint16 *)(a)) */
+static inline uint16 getreg16(unsigned int addr)
+{
+  uint16 retval;
+ __asm__ __volatile__("\tldrh %0, [%1]\n\t" : "=r"(retval) : "r"(addr));
+  return retval;
+}
+
+/* define putreg16(v,a)       (*(volatile uint16 *)(a) = (v)) */
+static inline void putreg16(uint16 val, unsigned int addr)
+{
+ __asm__ __volatile__("\tstrh %0, [%1]\n\t": : "r"(val), "r"(addr));
+}
+
+/* Most DM320 registers are 16-bits wide */
+
+#define getreg(a)   getreg16(1)
+#define putreg(v,a) putreg16(v,a)
+
+#endif
+
+#endif  /* __UP_ARCH_H */
diff --git a/nuttx/arch/arm/src/common/up_assert.c b/nuttx/arch/arm/src/common/up_assert.c
new file mode 100644
index 000000000..5c032c2f0
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_assert.c
@@ -0,0 +1,224 @@
+/************************************************************
+ * common/up_assert.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <debug.h>
+#include <nuttx/irq.h>
+#include "up_arch.h"
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/* Output debug info if stack dump is selected -- even if 
+ * debug is not selected.
+ */
+
+#ifdef CONFIG_ARCH_STACKDUMP
+# undef  lldbg
+# define lldbg lib_lowprintf
+#endif
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_getsp
+ ************************************************************/
+
+/* I don't know if the builtin to get SP is enabled */
+
+static inline uint32 up_getsp(void)
+{
+  uint32 sp;
+  __asm__
+  (
+    "\tmov %0, sp\n\t"
+    : "=r"(sp)
+  );
+  return sp;
+}
+
+/************************************************************
+ * Name: up_stackdump
+ ************************************************************/
+
+#ifdef CONFIG_ARCH_STACKDUMP
+static void up_stackdump(void)
+{
+  _TCB *rtcb        = (_TCB*)g_readytorun.head;
+  uint32 sp         = up_getsp();
+  uint32 stack_base;
+  uint32 stack_size;
+
+  if (rtcb->pid == 0)
+    {
+      stack_base = g_heapbase - 4;
+      stack_size = CONFIG_PROC_STACK_SIZE;
+    }
+  else
+    {
+      stack_base = (uint32)rtcb->adj_stack_ptr;
+      stack_size = (uint32)rtcb->adj_stack_size;
+    }
+
+  lldbg("stack_base: %08x\n", stack_base);
+  lldbg("stack_size: %08x\n", stack_size);
+  lldbg("sp:         %08x\n", sp);
+
+  if (sp >= stack_base || sp < stack_base - stack_size)
+    {
+      lldbg("ERROR: Stack pointer is not within allocated stack\n");
+      return;
+    }
+  else
+    {
+      uint32 stack = sp & ~0x1f;
+
+      for (stack = sp & ~0x1f; stack < stack_base; stack += 32)
+        {
+          uint32 *ptr = (uint32*)stack;
+          lldbg("%08x: %08x %08x %08x %08x %08x %08x %08x %08x\n",
+                 stack, ptr[0], ptr[1], ptr[2], ptr[3],
+                 ptr[4], ptr[5], ptr[6], ptr[7]);
+        }
+    }
+
+  if (current_regs)
+    {
+      int regs;
+
+      for (regs = REG_R0; regs <= REG_R15; regs += 8)
+        {
+          uint32 *ptr = (uint32*)&current_regs[regs];
+          lldbg("R%d: %08x %08x %08x %08x %08x %08x %08x %08x\n",
+                 regs, ptr[0], ptr[1], ptr[2], ptr[3],
+                 ptr[4], ptr[5], ptr[6], ptr[7]);
+        }
+      lldbg("CPSR: %08x\n", current_regs[REG_CPSR]);
+    }
+}
+#else
+# define up_stackdump()
+#endif
+
+/************************************************************
+ * Name: _up_assert
+ ************************************************************/
+
+static void _up_assert(int errorcode) /* __attribute__ ((noreturn)) */
+{
+  /* Are we in an interrupt handler or the idle task? */
+
+  if (current_regs || ((_TCB*)g_readytorun.head)->pid == 0)
+    {
+       (void)irqsave();
+        for(;;)
+          {
+#ifdef CONFIG_ARCH_LEDS
+            up_ledon(LED_PANIC);
+            up_delay(250);
+            up_ledoff(LED_PANIC);
+            up_delay(250);
+#endif
+          }
+    }
+  else
+    {
+      exit(errorcode);
+    }
+}
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_assert
+ ************************************************************/
+
+void up_assert(const ubyte *filename, int lineno)
+{
+#if CONFIG_TASK_NAME_SIZE > 0
+  _TCB *rtcb = (_TCB*)g_readytorun.head;
+#endif
+
+  up_ledon(LED_ASSERTION);
+#if CONFIG_TASK_NAME_SIZE > 0
+  lldbg("Assertion failed at file:%s line: %d task: %s\n",
+        filename, lineno, rtcb->name);
+#else
+  lldbg("Assertion failed at file:%s line: %d\n",
+        filename, lineno);
+#endif
+  up_stackdump();
+  _up_assert(EXIT_FAILURE);
+}
+
+/************************************************************
+ * Name: up_assert_code
+ ************************************************************/
+
+void up_assert_code(const ubyte *filename, int lineno, int errorcode)
+{
+#if CONFIG_TASK_NAME_SIZE > 0
+  _TCB *rtcb = (_TCB*)g_readytorun.head;
+#endif
+
+  up_ledon(LED_ASSERTION);
+#if CONFIG_TASK_NAME_SIZE > 0
+  lldbg("Assertion failed at file:%s line: %d task: %s error code: %d\n",
+        filename, lineno, rtcb->name, errorcode);
+#else
+  lldbg("Assertion failed at file:%s line: %d error code: %d\n",
+        filename, lineno, errorcode);
+#endif
+  up_stackdump();
+  _up_assert(errorcode);
+}
diff --git a/nuttx/arch/arm/src/common/up_blocktask.c b/nuttx/arch/arm/src/common/up_blocktask.c
new file mode 100644
index 000000000..b72604429
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_blocktask.c
@@ -0,0 +1,168 @@
+/************************************************************
+ * common/up_blocktask.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_block_task
+ *
+ * Description:
+ *   The currently executing task at the head of
+ *   the ready to run list must be stopped.  Save its context
+ *   and move it to the inactive list specified by task_state.
+ *
+ * Inputs:
+ *   tcb: Refers to a task in the ready-to-run list (normally
+ *     the task at the the head of the list).  It most be
+ *     stopped, its context saved and moved into one of the
+ *     waiting task lists.  It it was the task at the head
+ *     of the ready-to-run list, then a context to the new
+ *     ready to run task must be performed.
+ *   task_state: Specifies which waiting task list should be
+ *     hold the blocked task TCB.
+ *
+ ************************************************************/
+
+void up_block_task(_TCB *tcb, tstate_t task_state)
+{
+  /* Verify that the context switch can be performed */
+
+  if ((tcb->task_state < FIRST_READY_TO_RUN_STATE) ||
+      (tcb->task_state > LAST_READY_TO_RUN_STATE))
+    {
+      PANIC(OSERR_BADBLOCKSTATE);
+    }
+  else
+    {
+      _TCB *rtcb = (_TCB*)g_readytorun.head;
+      boolean switch_needed;
+
+      lldbg("Blocking TCB=%p\n", tcb);
+
+      /* Remove the tcb task from the ready-to-run list.  If we
+       * are blocking the task at the head of the task list (the
+       * most likely case), then a context switch to the next
+       * ready-to-run task is needed. In this case, it should
+       * also be true that rtcb == tcb.
+       */
+
+      switch_needed = sched_removereadytorun(tcb);
+
+      /* Add the task to the specified blocked task list */
+
+      sched_addblocked(tcb, (tstate_t)task_state);
+
+      /* If there are any pending tasks, then add them to the g_readytorun
+       * task list now
+       */
+
+      if (g_pendingtasks.head)
+        {
+          switch_needed |= sched_mergepending();
+        }
+
+      /* Now, perform the context switch if one is needed */
+
+      if (switch_needed)
+        {
+          /* Are we in an interrupt handler? */
+
+          if (current_regs)
+            {
+              /* Yes, then we have to do things differently.
+               * Just copy the current_regs into the OLD rtcb.
+               */
+
+               up_copystate(rtcb->xcp.regs, current_regs);
+
+              /* Restore the exception context of the rtcb at the (new) head 
+               * of the g_readytorun task list.
+               */
+
+              rtcb = (_TCB*)g_readytorun.head;
+              lldbg("New Active Task TCB=%p\n", rtcb);
+
+              /* Then switch contexts */
+
+              up_copystate(current_regs, rtcb->xcp.regs);
+            }
+
+          /* Copy the user C context into the TCB at the (old) head of the
+           * g_readytorun Task list. if up_saveusercontext returns a non-zero
+           * value, then this is really the previously running task restarting!
+           */
+
+          else if (!up_saveusercontext(rtcb->xcp.regs))
+            {
+              /* Restore the exception context of the rtcb at the (new) head 
+               * of the g_readytorun task list.
+               */
+
+              rtcb = (_TCB*)g_readytorun.head;
+              lldbg("New Active Task TCB=%p\n", rtcb);
+
+              /* Then switch contexts */
+
+              up_fullcontextrestore(rtcb->xcp.regs);
+            }
+        }
+    }
+}
diff --git a/nuttx/arch/arm/src/common/up_cache.S b/nuttx/arch/arm/src/common/up_cache.S
new file mode 100644
index 000000000..5e6f6610b
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_cache.S
@@ -0,0 +1,74 @@
+/********************************************************************
+ * common/up_cache.S
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ********************************************************************/
+
+/********************************************************************
+ * Included Files
+ ********************************************************************/
+
+#include <nuttx/config.h>
+#include "up_internal.h"
+#include "up_arch.h"
+
+/********************************************************************
+ * Definitions
+ ********************************************************************/
+
+#define CACHE_DLINESIZE    32
+
+/********************************************************************
+ * Assembly Macros
+ ********************************************************************/
+
+/**************************************************************************
+ * Name: up_flushicache
+ **************************************************************************/
+
+/* Esure coherency between the Icache and the Dcache in the region described 
+ * by r0=start and r1=end.
+ */
+	.globl	up_flushicache
+	.type	up_flushicache,%function
+up_flushicache:
+	bic	r0, r0, #CACHE_DLINESIZE - 1
+1:	mcr	p15, 0, r0, c7, c10, 1		/* Clean D entry */
+	mcr	p15, 0, r0, c7, c5, 1		/* Invalidate I entry */
+	add	r0, r0, #CACHE_DLINESIZE
+	cmp	r0, r1
+	blo	1b
+	mcr	p15, 0, r0, c7, c10, 4		/* Drain WB */
+	mov	pc, lr
+	.size	up_flushicache, .-up_flushicache
+	.end
+
diff --git a/nuttx/arch/arm/src/common/up_copystate.c b/nuttx/arch/arm/src/common/up_copystate.c
new file mode 100644
index 000000000..9d21630e1
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_copystate.c
@@ -0,0 +1,75 @@
+/************************************************************
+ * common/up_copystate.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_undefinedinsn
+ ************************************************************/
+
+/* A little faster than most memcpy's */
+
+void up_copystate(uint32 *dest, uint32 *src)
+{
+  int i;
+  for (i = 0; i < XCPTCONTEXT_REGS; i++)
+    {
+      *dest++ = *src++;
+    }
+}
+
diff --git a/nuttx/arch/arm/src/common/up_createstack.c b/nuttx/arch/arm/src/common/up_createstack.c
new file mode 100644
index 000000000..a68e2edf3
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_createstack.c
@@ -0,0 +1,128 @@
+/************************************************************
+ * common/up_createstack.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/kmalloc.h>
+#include <nuttx/arch.h>
+#include "up_arch.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Types
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+/************************************************************
+ * Global Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_create_stack
+ *
+ * Description:
+ *   Allocate a stack for a new thread and setup
+ *   up stack-related information in the TCB.
+ *
+ *   The following TCB fields must be initialized:
+ *   adj_stack_size: Stack size after adjustment for hardware,
+ *     processor, etc.  This value is retained only for debug
+ *     purposes.
+ *   stack_alloc_ptr: Pointer to allocated stack
+ *   adj_stack_ptr: Adjusted stack_alloc_ptr for HW.  The
+ *     initial value of the stack pointer.
+ *
+ * Inputs:
+ *   tcb: The TCB of new task
+ *   stack_size:  The requested stack size.  At least this much
+ *     must be allocated.
+ ************************************************************/
+
+STATUS up_create_stack(_TCB *tcb, size_t stack_size)
+{
+  if (tcb->stack_alloc_ptr &&
+      tcb->adj_stack_size != stack_size)
+    {
+      sched_free(tcb->stack_alloc_ptr);
+      tcb->stack_alloc_ptr = NULL;
+    }
+
+   if (!tcb->stack_alloc_ptr)
+     {
+       tcb->stack_alloc_ptr = (uint32 *)kzmalloc(stack_size);
+     }
+
+   if (tcb->stack_alloc_ptr)
+     {
+       size_t top_of_stack;
+       size_t size_of_stack;
+
+       /* The Arm7Tdmi uses a push-down stack:  the stack grows
+	* toward loweraddresses in memory.  The stack pointer
+	* register, points to the lowest, valid work address
+	* (the "top" of the stack).  Items on the stack are
+	* referenced as positive word offsets from sp.
+	*/
+
+       top_of_stack = (uint32)tcb->stack_alloc_ptr + stack_size - 4;
+
+       /* The Arm7Tdmi stack must be aligned at word (4 byte)
+	* boundaries. If necessary top_of_stack must be rounded
+	* down to the next boundary
+	*/
+
+       top_of_stack &= ~3;
+       size_of_stack = top_of_stack - (uint32)tcb->stack_alloc_ptr + 4;
+
+       /* Save the adjusted stack values in the _TCB */
+
+       tcb->adj_stack_ptr  = (uint32*)top_of_stack;
+       tcb->adj_stack_size = size_of_stack;
+
+       up_ledon(LED_STACKCREATED);
+       return OK;
+     }
+
+   return ERROR;
+}
diff --git a/nuttx/arch/arm/src/common/up_dataabort.c b/nuttx/arch/arm/src/common/up_dataabort.c
new file mode 100644
index 000000000..a7b48ed77
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_dataabort.c
@@ -0,0 +1,81 @@
+/************************************************************
+ * common/up_dataabort.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <nuttx/irq.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/* Output debug info if stack dump is selected -- even if 
+ * debug is not selected.
+ */
+
+#ifdef CONFIG_ARCH_STACKDUMP
+# undef  lldbg
+# define lldbg lib_lowprintf
+#endif
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_dataabort
+ ************************************************************/
+
+void up_dataabort(uint32 *regs)
+{
+  lldbg("Data abort at 0x%x\n", regs[REG_PC]);
+  current_regs = regs;
+  PANIC(OSERR_ERREXCEPTION);
+}
diff --git a/nuttx/arch/arm/src/common/up_delay.c b/nuttx/arch/arm/src/common/up_delay.c
new file mode 100644
index 000000000..19e98484a
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_delay.c
@@ -0,0 +1,100 @@
+/************************************************************
+ * common/up_delay.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <semaphore.h>
+#include <string.h>
+#include <errno.h>
+#include <debug.h>
+#include <nuttx/irq.h>
+#include <nuttx/arch.h>
+#include <nuttx/fs.h>
+#include <arch/serial.h>
+#include "up_arch.h"
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Types
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+/************************************************************
+ * Private Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_delay
+ *
+ * Description:
+ *   Delay inline for the requested number of milliseconds.
+ *   NOT multi-tasking friendly.
+ *
+ ************************************************************/
+
+void up_delay(int milliseconds)
+{
+  volatile int i;
+  volatile int j;
+
+  for (i = 0; i < milliseconds; i++)
+    {
+        for (j = 0; j < CONFIG_BOARD_LOOPSPERMSEC; j++)
+          {
+          }
+    }
+}
diff --git a/nuttx/arch/arm/src/common/up_doirq.c b/nuttx/arch/arm/src/common/up_doirq.c
new file mode 100644
index 000000000..d49c3c4fa
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_doirq.c
@@ -0,0 +1,104 @@
+/************************************************************
+ * common/up_doirq.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <nuttx/irq.h>
+#include <nuttx/arch.h>
+#include <assert.h>
+#include "up_arch.h"
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Public Data
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+void up_doirq(int irq, uint32* regs)
+{
+  up_ledon(LED_INIRQ);
+#ifdef CONFIG_SUPPRESS_INTERRUPTS
+  PANIC(OSERR_ERREXCEPTION);
+#else
+  if ((unsigned)irq < NR_IRQS)
+    {
+       /* Current regs non-zero indicates that we are processing
+        * an interrupt; current_regs is also used to manage
+        * interrupt level context switches.
+        */
+
+       current_regs = regs;
+
+       /* Mask and acknowledge the interrupt */
+
+       up_maskack_irq(irq);
+
+       /* Deliver the IRQ */
+
+       irq_dispatch(irq, regs);
+
+       /* Indicate that we are no long in an interrupt handler */
+
+       current_regs = NULL;
+
+       /* Unmask the last interrupt (global interrupts are still
+        * disabled.
+        */
+
+       up_enable_irq(irq);
+    }
+  up_ledoff(LED_INIRQ);
+#endif
+}
diff --git a/nuttx/arch/arm/src/common/up_exit.c b/nuttx/arch/arm/src/common/up_exit.c
new file mode 100644
index 000000000..94a467006
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_exit.c
@@ -0,0 +1,188 @@
+/************************************************************
+ * common/up_exit.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+#ifdef CONFIG_DUMP_ON_EXIT
+#include <nuttx/fs.h>
+#endif
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: _up_dumponexit
+ *
+ * Description:
+ *   Dump the state of all tasks whenever on task exits.  This
+ *   is debug instrumentation that was added to check file-
+ *   related reference counting but could be useful again
+ *   sometime in the future.
+ *
+ ************************************************************/
+
+#if defined(CONFIG_DUMP_ON_EXIT) && defined(CONFIG_DEBUG)
+static void _up_dumponexit(FAR _TCB *tcb, FAR void *arg)
+{
+  int i;
+  dbg("  TCB=%p name=%s\n", tcb, tcb->argv[0]);
+  if (tcb->filelist)
+    {
+      dbg("    filelist refcount=%d\n",
+          tcb->filelist->fl_crefs);
+
+      for (i = 0; i < CONFIG_NFILE_DESCRIPTORS; i++)
+        {
+          struct inode *inode = tcb->filelist->fl_files[i].f_inode;
+          if (inode)
+            {
+              dbg("      fd=%d refcount=%d\n",
+                  i, inode->i_crefs);
+            }
+        }
+    }
+
+  if (tcb->streams)
+    {
+      dbg("    streamlist refcount=%d\n",
+          tcb->streams->sl_crefs);
+
+      for (i = 0; i < CONFIG_NFILE_STREAMS; i++)
+        {
+          struct file_struct *filep = &tcb->streams->sl_streams[i];
+          if (filep->fs_filedes >= 0)
+            {
+              dbg("      fd=%d nbytes=%d\n",
+                  filep->fs_filedes,
+                  filep->fs_bufpos - filep->fs_bufstart);
+            }
+        }
+    }
+}
+#endif
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: _exit
+ *
+ * Description:
+ *   This function causes the currently executing task to cease
+ *   to exist.  This is a special case of task_delete().
+ *
+ ************************************************************/
+
+void _exit(int status)
+{
+  _TCB* tcb = (_TCB*)g_readytorun.head;
+
+  /* Disable interrupts.  They will be restored when the next
+   * task is started.
+   */
+
+  (void)irqsave();
+
+  lldbg("TCB=%p exitting\n", tcb);
+
+#if defined(CONFIG_DUMP_ON_EXIT) && defined(CONFIG_DEBUG)
+  dbg("Other tasks:\n");
+  sched_foreach(_up_dumponexit, NULL);
+#endif
+
+  /* Remove the tcb task from the ready-to-run list.  We can
+   * ignore the return value because we know that a context
+   * switch is needed.
+   */
+
+  (void)sched_removereadytorun(tcb);
+
+  /* We are not in a bad stack-- the head of the ready to run task list
+   * does not correspond to the thread that is running.  Disabling pre-
+   * emption on this TCB should be enough to keep things stable.
+   */
+
+  sched_lock();
+
+  /* Move the TCB to the specified blocked task list and delete it */
+
+  sched_addblocked(tcb, TSTATE_TASK_INACTIVE);
+  task_delete(tcb->pid);
+
+  /* If there are any pending tasks, then add them to the g_readytorun
+   * task list now
+   */
+
+  if (g_pendingtasks.head)
+    {
+      (void)sched_mergepending();
+    }
+
+  /* Now calling sched_unlock() should have no effect */
+
+  sched_unlock();
+
+  /* Now, perform the context switch to the new ready-to-run task at the
+   * head of the list.
+   */
+
+  tcb = (_TCB*)g_readytorun.head;
+  lldbg("New Active Task TCB=%p\n", tcb);
+
+  /* Then switch contexts */
+
+  up_fullcontextrestore(tcb->xcp.regs);
+}
+
diff --git a/nuttx/arch/arm/src/common/up_fullcontextrestore.S b/nuttx/arch/arm/src/common/up_fullcontextrestore.S
new file mode 100644
index 000000000..21529e6aa
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_fullcontextrestore.S
@@ -0,0 +1,117 @@
+/**************************************************************************
+ * common/up_fullcontextrestore.S
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ **************************************************************************/
+
+/**************************************************************************
+ * Included Files
+ **************************************************************************/
+
+#include <nuttx/irq.h>
+#include "up_internal.h"
+
+/**************************************************************************
+ * Private Definitions
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Types
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Function Prototypes
+ **************************************************************************/
+
+/**************************************************************************
+ * Global Variables
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Variables
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Functions
+ **************************************************************************/
+
+/**************************************************************************
+ * Public Functions
+ **************************************************************************/
+
+/**************************************************************************
+ * Name: up_fullcontextrestore
+ **************************************************************************/
+
+	.globl	up_fullcontextrestore
+	.type	up_fullcontextrestore, function
+up_fullcontextrestore:
+
+	/* On entry, a1 (r0) holds address of the register save area */
+
+	/* Recover all registers except for r0, r1, R15, and CPSR */
+
+	add	r1, r0, #(4*REG_R2)	/* Offset to REG_R2 storage */
+	ldmia	r1, {r2-r14}		/* Recover registers */
+
+	/* Create a stack frame to hold the PC */
+
+	sub	sp, sp, #(3*4)		/* Frame for three registers */
+	ldr	r1, [r0, #(4*REG_R0)]	/* Fetch the stored r0 value */
+	str	r1, [sp]		/* Save it at the top of the stack */
+	ldr	r1, [r0, #(4*REG_R1)]	/* Fetch the stored r1 value */
+	str	r1, [sp, #4]		/* Save it in the stack */
+	ldr	r1, [r0, #(4*REG_PC)]	/* Fetch the stored pc value */
+	str	r1, [sp, #8]		/* Save it at the bottom of the frame */
+
+	/* Now we can restore the CPSR.  We wait until we are completely
+	 * finished with the context save data to do this. Restore the CPSR
+	 * may re-enable and interrupts and we couldt be in a context
+	 * where save structure is only protected by interrupts being disabled.
+         */
+
+	ldr	r1, [r0, #(4*REG_CPSR)]	/* Fetch the stored CPSR value */
+	msr	cpsr, r1		/* Set the CPSR */
+
+	/* Now recover r0 and r1 */
+
+	ldr	r0, [sp]
+	ldr	r1, [sp, #4]
+	add	sp, sp, #(2*4)
+
+	/* Then return to the address at the stop of the stack,
+	 * destroying the stack frame
+	 */
+
+	ldr	pc, [sp], #4
+	.size up_fullcontextrestore, . - up_fullcontextrestore
+
diff --git a/nuttx/arch/arm/src/common/up_head.S b/nuttx/arch/arm/src/common/up_head.S
new file mode 100644
index 000000000..65403ee23
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_head.S
@@ -0,0 +1,324 @@
+/********************************************************************
+ * common/up_head.S
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ********************************************************************/
+
+/********************************************************************
+ * Included Files
+ ********************************************************************/
+
+#include <nuttx/config.h>
+#include "up_internal.h"
+#include "up_arch.h"
+
+/**************************************************************************
+ * Conditional Compilation
+ **************************************************************************/
+
+#undef ALIGNMENT_TRAP
+#undef CPU_DCACHE_WRITETHROUGH
+#undef CPU_CACHE_ROUND_ROBIN
+#undef CPU_DCACHE_DISABLE
+#undef CPU_ICACHE_DISABLE
+
+/********************************************************************
+ * Definitions
+ ********************************************************************/
+
+/* The physical address of the beginning of SDRAM is provided by
+ * CONFIG_DRAM_START.  The size of installed SDRAM is provided by
+ * CONFIG_DRAM_SIZE.  The virtual address of SDRAM is provided by
+ * CONFIG_DRAM_VSTART.
+ */
+
+#define NSDRAM_SECTIONS (CONFIG_DRAM_SIZE >> 20)
+
+/********************************************************************
+ * Assembly Macros
+ ********************************************************************/
+
+/* Since the page table is closely related to the NuttX base
+ * address, we can convert the page table base address to the
+ * base address of the section containing both.
+ */
+
+	.macro	mksection, section, pgtable
+	bic	\section, \pgtable, #0x000ff000
+	.endm
+
+/* This macro will modify r0, r1, r2 and r14 */
+
+#ifdef CONFIG_DEBUG
+	.macro	showprogress, code
+	mov	r0, #\code
+	bl	up_lowputc
+	.endm
+#else
+	.macro	showprogress, code
+	.endm
+#endif
+
+/********************************************************************
+ * Name: __start
+ ********************************************************************/
+
+/* We assume the bootloader has already initialized most of the h/w for
+ * us and that only leaves us having to do some os specific things
+ * below.
+ */
+	.text
+        .global __start
+	.type	__start, #function
+__start:
+	/* Make sure that we are in SVC mode with all IRQs disabled */
+
+	mov	r0, #(SVC_MODE | PSR_I_BIT | PSR_F_BIT)
+	msr	cpsr_c, r0
+
+	/* Clear the 16K level 1 page table */
+
+	ldr	r4, .LCppgtable		/* r4=phys. page table */
+	mov	r0, r4
+	mov	r1, #0
+	add	r2, r0, #PGTABLE_SIZE
+.Lpgtableclear:
+	str	r1, [r0], #4
+	str	r1, [r0], #4
+	str	r1, [r0], #4
+	str	r1, [r0], #4
+	teq	r0, r2
+	bne	.Lpgtableclear
+
+	/* Create identity mapping for first MB section to support
+	 * this startup logic executing out of the physical address
+	 * space.  This identity mapping will be removed by .Lvstart
+	 * (see below).
+	 */
+
+	mksection r0, r4			/* r0=phys. base section */
+	ldr	r1, .LCmmuflags		/* FLGS=MMU_MEMFLAGS */
+	add	r3, r1, r0		/* r3=flags + base */
+	str	r3, [r4, r0, lsr #18]	/* identity mapping */
+
+	/* Create a "normal" single section mapping for the first
+	 * MB of memory.  Now, we have the first 1MB mapping to
+	 * both phyical and virtual addresses.  The reset of the
+	 * SDRAM mapping will be completed in .Lvstart once we have
+	 * moved the physical mapping out of the way.
+	 */
+
+	ldr	r2, .LCvpgtable		/* r2=virt. page table */
+	mksection r0, r2			/* r0=virt. base section */
+	str	r3, [r4, r0, lsr #18]	/* identity mapping */
+
+	/* The following logic will set up the ARM926 for normal operation */
+
+	mov	r0, #0
+	mcr	p15, 0, r0, c7, c7		/* Invalidate I,D caches */
+	mcr	p15, 0, r0, c7, c10, 4	/* Drain write buffer */
+	mcr	p15, 0, r0, c8, c7		/* Invalidate I,D TLBs */
+	mcr	p15, 0, r4, c2, c0		/* Load page table pointer */
+
+#ifdef CPU_DCACHE_WRITETHROUGH
+	mov	r0, #4			/* Disable write-back on caches explicitly */
+	mcr	p15, 7, r0, c15, c0, 0
+#endif 
+
+	/* Enable the MMU and caches
+	 * lr = Resume at .Lvstart with the MMU enabled
+	 */
+
+	ldr	lr, .LCvstart			/* Abs. virtual address */
+
+	mov	r0, #0x1f			/* Domains 0, 1 = client */
+	mcr	p15, 0, r0, c3, c0		/* Load domain access register */
+	mrc	p15, 0, r0, c1, c0		/* Get control register */
+	
+	/* Clear bits (see start.h) */
+
+	bic	r0, r0, #(CR_R|CR_F|CR_Z)
+	bic	r0, r0, #(CR_A|CR_C|CR_W)
+	bic	r0, r0, #(CR_I)
+
+	/* Set bits (see start.h) */
+
+	orr	r0, r0, #(CR_M|CR_P|CR_D)
+	orr	r0, r0, #(CR_S|CR_V)
+
+#ifdef CPU_CACHE_ROUND_ROBIN
+	orr	r0, r0, #(CR_RR)
+#endif
+#ifndef CPU_DCACHE_DISABLE
+	orr	r0, r0, #(CR_C)
+#endif
+#ifndef CPU_ICACHE_DISABLE
+	orr	r0, r0, #(CR_I)
+#endif
+#ifdef ALIGNMENT_TRAP
+	orr	r0, r0, #(CR_A)
+#endif
+	mcr	p15, 0, r0, c1, c0, 0		/* write control reg */
+
+	/* Get TMP=2 Processor ID register */
+
+	mrc	p15, 0, r1, c0, c0, 0		/* read id reg */
+	mov	r1, r1
+	mov	r1, r1
+
+	mov	pc, lr
+
+/**************************************************************************
+ * PC_Relative Data
+ **************************************************************************/
+
+	/* These addresses are all virtual address */
+	
+	.type	.LCvstart, %object
+.LCvstart:
+	.long	.Lvstart
+	.type	.LCmmuflags, %object
+.LCmmuflags:
+	.long	MMU_MEMFLAGS
+	.type	.LCppagetable, %object
+.LCppgtable:
+	.long	CONFIG_DRAM_START  /* Physical start of DRAM */
+	.type	.LCvpagetable, %object
+.LCvpgtable:
+	.long	CONFIG_DRAM_VSTART /* Virtual start of DRAM */
+	.size	_start, .-_start
+
+/**************************************************************************
+ * Name: .Lvstart
+ **************************************************************************/
+
+/* The following is executed after the MMU has been enabled. This uses
+ * absolute addresses; this is not position independent.
+ */
+	.align	5
+	.local	.Lvstart
+	.type	.Lvstart, %function
+.Lvstart:
+
+	/* Remove the temporary null mapping */
+
+	ldr	r4, .LCvpgtable		/* r4=virtual page table */
+	ldr	r1, .LCppgtable		/* r1=phys. page table */
+	mksection r3, r1			/* r2=phys. base addr */
+	mov	r0, #0			/* flags + base = 0 */
+	str	r0, [r4, r3, lsr #18]	/* Undo identity mapping */
+
+	/* Now setup the pagetables for our normal SDRAM mappings
+	 * mapped region.  We round NUTTX_START_VADDR down to the
+	 * nearest megabyte boundary.
+	 */
+
+	ldr	r1, .LCmmuflags		/* FLGS=MMU_MEMFLAGS */
+	add	r3, r3, r1		/* r3=flags + base */
+
+	add	r0, r4, #(NUTTX_START_VADDR & 0xff000000) >> 18
+	bic	r2, r3, #0x00f00000
+	str	r2, [r0]
+
+	add	r0, r0, #(NUTTX_START_VADDR & 0x00f00000) >> 18
+	str	r3, [r0], #4
+
+	/* Now map the remaining NSDRAM_SECTIONS-1 SDRAM sections */
+
+	.rept	NSDRAM_SECTIONS-1
+	add	r3, r3, #SECTION_SIZE
+	str	r3, [r0], #4
+	.endr
+
+	/* Zero BSS and set up the stack pointer */
+
+	adr	r0, .Linitparms
+	ldmia	r0, {r0, r1, sp}
+
+	/* Clear the frame pointer and .bss */
+
+	mov     fp, #0
+
+.Lbssinit:	
+	cmp     r0, r1		       /* Clear up to _bss_end_ */
+	strcc	fp, [r0],#4
+	bcc	.Lbssinit
+
+	/* Perform early C-level initialization */
+
+	bl	up_boot
+
+	/* Set up the LEDs */
+
+#ifdef CONFIG_ARCH_LEDS
+	bl	up_ledinit
+#endif
+	/* Perform early serial initialization */
+
+#ifdef CONFIG_DEV_CONSOLE
+	bl      up_earlyserialinit
+#endif
+
+	/* Finally branch to the OS entry point */
+
+	mov	lr, #0
+	b	os_start
+
+	/* Variables:
+	 * _sbss is the start of the BSS region (see ld.script)
+	 * _ebss is the end of the BSS regsion (see ld.script)
+	 * The idle task stack starts at the end of BSS and is
+	 * of size CONFIG_PROC_STACK_SIZE.  The heap continues
+	 * from there until the end of memory.  See g_heapbase
+	 * below.
+	 */
+
+.Linitparms:
+	.long	_sbss
+	.long	_ebss
+	.long	_ebss+CONFIG_PROC_STACK_SIZE-4
+	.size	.Lvstart, .-.Lvstart
+
+	/* This global variable is unsigned long g_heapbase and is
+	 * exported from here only because of its coupling to .Linitparms
+	 * above.
+	 */
+
+	.data
+	.align	4
+	.globl	g_heapbase
+	.type	g_heapbase, object
+g_heapbase:
+	.long	_ebss+CONFIG_PROC_STACK_SIZE
+	.size	g_heapbase, .-g_heapbase
+	.end
+
diff --git a/nuttx/arch/arm/src/common/up_idle.c b/nuttx/arch/arm/src/common/up_idle.c
new file mode 100644
index 000000000..d90b50aa8
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_idle.c
@@ -0,0 +1,87 @@
+/************************************************************
+ * common/up_idle.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <nuttx/arch.h>
+#include "up_internal.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_idle
+ *
+ * Description:
+ *   up_idle() is the logic that will be executed when their
+ *   is no other ready-to-run task.  This is processor idle
+ *   time and will continue until some interrupt occurs to
+ *   cause a context switch from the idle task.
+ *
+ *   Processing in this state may be processor-specific. e.g.,
+ *   this is where power management operations might be
+ *   performed.
+ *
+ ************************************************************/
+
+void up_idle(void)
+{
+#if defined(CONFIG_SUPPRESS_INTERRUPTS) || defined(CONFIG_SUPPRESS_TIMER_INTS)
+  /* If the system is idle and there are no timer interrupts,
+   * then process "fake" timer interrupts. Hopefully, something
+   * will wake up.
+   */
+
+  sched_process_timer();
+#endif
+}
+
diff --git a/nuttx/arch/arm/src/common/up_initialize.c b/nuttx/arch/arm/src/common/up_initialize.c
new file mode 100644
index 000000000..9fad207e5
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_initialize.c
@@ -0,0 +1,104 @@
+/************************************************************
+ * common/up_initialize.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include <nuttx/fs.h>
+#include "up_arch.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Types
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+/************************************************************
+ * Global Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_initialize
+ *
+ * Description:
+ *   up_initialize will be called once during OS
+ *   initialization after the basic OS services have been
+ *   initialized.  The architecture specific details of
+ *   initializing the OS will be handled here.  Such things as
+ *   setting up interrupt service routines, starting the
+ *   clock, and registering device drivers are some of the
+ *   things that are different for each processor and hardware
+ *   platform.
+ *
+ *   up_initialize is called after the OS initialized but
+ *   before the init process has been started and before the
+ *   libraries have been initialized.  OS services and driver
+ *   services are available.
+ *
+ ************************************************************/
+
+void up_initialize(void)
+{
+  /* Initialize global variables */
+
+  current_regs = NULL;
+
+  /* Initialize the interrupt subsystem */
+
+  up_irqinitialize();
+
+  /* Initialize the system timer interrupt */
+
+#if !defined(CONFIG_SUPPRESS_INTERRUPTS) && !defined(CONFIG_SUPPRESS_TIMER_INTS)
+  up_timerinit();
+#endif
+
+  /* Register devices */
+
+  devnull_register();   /* Standard /dev/null */
+
+  /* Initialize the serial device driver */
+
+  up_serialinit();
+  up_ledon(LED_IRQSENABLED);
+}
diff --git a/nuttx/arch/arm/src/common/up_initialstate.c b/nuttx/arch/arm/src/common/up_initialstate.c
new file mode 100644
index 000000000..64608d481
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_initialstate.c
@@ -0,0 +1,91 @@
+/************************************************************
+ * common/up_initialstate.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <string.h>
+#include <nuttx/arch.h>
+#include "up_internal.h"
+#include "up_arch.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_initial_state
+ *
+ * Description:
+ *   A new thread is being started and a new TCB
+ *   has been created. This function is called to initialize
+ *   the processor specific portions of the new TCB.
+ *
+ *   This function must setup the intial architecture registers
+ *   and/or  stack so that execution will begin at tcb->start
+ *   on the next context switch.
+ *
+ ************************************************************/
+
+void up_initial_state(_TCB *tcb)
+{
+  struct xcptcontext *xcp = &tcb->xcp;
+
+  /* Initialize the initial exception register context structure */
+
+  memset(xcp, 0, sizeof(struct xcptcontext));
+  xcp->regs[REG_SP]   = (uint32)tcb->adj_stack_ptr;
+  xcp->regs[REG_PC]   = (uint32)tcb->start;
+#ifdef CONFIG_SUPPRESS_INTERRUPTS
+  xcp->regs[REG_CPSR] = SVC_MODE | PSR_I_BIT | PSR_F_BIT;
+#else
+  xcp->regs[REG_CPSR] = SVC_MODE | PSR_F_BIT;
+#endif
+}
diff --git a/nuttx/arch/arm/src/common/up_internal.h b/nuttx/arch/arm/src/common/up_internal.h
new file mode 100644
index 000000000..185b4e8ab
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_internal.h
@@ -0,0 +1,161 @@
+/************************************************************
+ * common/up_internal.h
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+#ifndef __UP_INTERNAL_H
+#define __UP_INTERNAL_H
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/* Bring-up debug configurations.  These are here (vs defconfig)
+ * because these should only be controlled during low level
+ * board bring-up and not part of normal platform configuration.
+ */
+
+#undef  CONFIG_SUPPRESS_INTERRUPTS    /* Do not enable interrupts */
+#undef  CONFIG_SUPPRESS_TIMER_INTS    /* No timer */
+#undef  CONFIG_SUPPRESS_SERIAL_INTS   /* Console will poll */
+#undef  CONFIG_SUPPRESS_UART_CONFIG   /* Do not reconfig UART */
+#define CONFIG_DUMP_ON_EXIT         1 /* Dump task state on exit */
+
+/************************************************************
+ * Public Types
+ ************************************************************/
+
+#ifndef __ASSEMBLY__
+typedef void (*up_vector_t)(void);
+#endif
+
+/************************************************************
+ * Public Variables
+ ************************************************************/
+
+#ifndef __ASSEMBLY__
+/* This holds a references to the current interrupt level
+ * register storage structure.  If is non-NULL only during
+ * interrupt processing.
+ */
+
+extern uint32 *current_regs;
+
+/* This is the beginning of heap as provided from up_head.S.
+ * This is the first address in DRAM after the loaded
+ * program+bss+idle stack.  The end of the heap is
+ * CONFIG_DRAM_END
+ */
+
+extern uint32 g_heapbase;
+#endif
+
+/************************************************************
+ * Inline Functions
+ ************************************************************/
+
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+#ifndef __ASSEMBLY__
+
+/* Defined in files with the same name as the function */
+
+extern void up_boot(void);
+extern void up_copystate(uint32 *dest, uint32 *src);
+extern void up_dataabort(uint32 *regs);
+extern void up_delay(int milliseconds);
+extern void up_doirq(uint32 *regs);
+extern void up_fullcontextrestore(uint32 *regs) __attribute__ ((noreturn));
+extern void up_irqinitialize(void);
+extern void up_prefetchabort(uint32 *regs);
+extern int  up_saveusercontext(uint32 *regs);
+extern void up_sigdeliver(void);
+extern void up_syscall(uint32 *regs);
+extern int  up_timerisr(int irq, uint32 *regs);
+extern void up_undefinedinsn(uint32 *regs);
+
+#ifdef CONFIG_DEBUG
+extern void up_lowputc(char ch);
+#else
+# define up_lowputc(ch)
+#endif
+
+/* Defined in up_vectors.S */
+
+extern void up_vectorundefinsn(void);
+extern void up_vectorswi(void);
+extern void up_vectorprefetch(void);
+extern void up_vectordata(void);
+extern void up_vectoraddrexcptn(void);
+extern void up_vectorirq(void);
+extern void up_vectorfiq(void);
+
+/* Defined in up_serial.c */
+
+extern void up_earlyserialinit(void);
+extern void up_serialinit(void);
+
+/* Defined in up_watchdog.c */
+
+extern void up_wdtinit(void);
+
+/* Defined in up_timerisr.c */
+
+extern void up_timerinit(void);
+
+/* Defined in up_irq.c */
+
+extern void up_maskack_irq(int irq);
+
+/* Defined in board/up_leds.c */
+
+#ifdef CONFIG_ARCH_LEDS
+extern void up_ledinit(void);
+extern void up_ledon(int led);
+extern void up_ledoff(int led);
+#else
+# define up_ledinit()
+# define up_ledon(led)
+# define up_ledoff(led)
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif  /* __UP_INTERNAL_H */
diff --git a/nuttx/arch/arm/src/common/up_interruptcontext.c b/nuttx/arch/arm/src/common/up_interruptcontext.c
new file mode 100644
index 000000000..a8c3210aa
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_interruptcontext.c
@@ -0,0 +1,68 @@
+/************************************************************
+ * common/up_interruptcontext.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <nuttx/arch.h>
+#include <nuttx/irq.h>
+#include "up_internal.h"
+
+/************************************************************
+ * Private Types
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+/************************************************************
+ * Global Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_interrupt_context
+ *
+ * Description: Return TRUE is we are currently executing in
+ * the interrupt handler context.
+ ************************************************************/
+
+boolean up_interrupt_context(void)
+{
+   return current_regs != NULL;
+}
diff --git a/nuttx/arch/arm/src/common/up_nommuhead.S b/nuttx/arch/arm/src/common/up_nommuhead.S
new file mode 100644
index 000000000..9d10449a7
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_nommuhead.S
@@ -0,0 +1,162 @@
+/********************************************************************
+ * common/up_nommuhead.S
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ********************************************************************/
+
+/********************************************************************
+ * Included Files
+ ********************************************************************/
+
+#include <nuttx/config.h>
+#include "up_internal.h"
+#include "up_arch.h"
+
+/********************************************************************
+ * Macros
+ ********************************************************************/
+
+	/* This macro will modify r0, r1, r2 and r14 */
+
+#ifdef CONFIG_DEBUG
+	.macro	showprogress, code
+	mov	r0, #\code
+	bl	up_lowputc
+	.endm
+#else
+	.macro	showprogress, code
+	.endm
+#endif
+
+/********************************************************************
+ * OS Entry Point
+ ********************************************************************/
+
+/* We assume the bootloader has already initialized most of the h/w for
+ * us and that only leaves us having to do some os specific things
+ * below.
+ */
+	.text
+        .global __start
+	.type	__start, #function
+__start:
+
+	/* First, setup initial processor mode */
+
+	mov	r0, #(SVC_MODE | PSR_I_BIT | PSR_F_BIT )
+	msr	cpsr, r0
+
+	showprogress 'A'
+
+	/* Setup system stack (and get the BSS range) */
+
+	adr	r0, LC0
+	ldmia   r0, {r4, r5, sp}
+
+	/* Clear system BSS section */
+
+	mov	r0, #0
+1:	cmp	r4, r5
+	strcc	r0, [r4], #4
+	bcc	1b
+
+	showprogress 'B'
+
+	/* Copy system .data sections to new home in RAM. */
+
+#ifdef CONFIG_BOOT_FROM_FLASH
+
+	adr	r3, LC2
+	ldmia	r3, {r0, r1, r2}
+
+1:	ldmia	r0!, {r3 - r10}
+	stmia	r1!, {r3 - r10}
+	cmp	r1, r2
+	blt	1b
+
+#endif
+	/* Perform early serial initialization */
+
+	mov	fp, #0
+	bl	up_earlyserialinit
+
+#ifdef CONFIG_DEBUG
+	mov	r0, #'C'
+	bl	up_putc
+	mov	r0, #'\n'
+	bl	up_putc
+#endif
+	/* Initialize onboard LEDs */
+
+#ifdef CONFIG_ARCH_LEDS
+	bl	up_ledinit
+#endif
+
+	/* Then jump to OS entry */
+
+	b	os_start
+
+	/* Variables:
+	 * _sbss is the start of the BSS region (see ld.script)
+	 * _ebss is the end of the BSS regsion (see ld.script)
+	 * The idle task stack starts at the end of BSS and is
+	 * of size CONFIG_PROC_STACK_SIZE.  The heap continues
+	 * from there until the end of memory.  See g_heapbase
+	 * below.
+	 */
+
+LC0:	.long	_sbss
+	.long	_ebss
+	.long	_ebss+CONFIG_PROC_STACK_SIZE-4
+
+#ifdef CONFIG_BOOT_FROM_FLASH
+LC2:	.long	_eronly	/* Where .data defaults are stored in FLASH */
+	.long	_sdata	/* Where .data needs to reside in SDRAM */
+	.long	_edata
+#endif
+	.size	__start, .-__start
+
+	/* This global variable is unsigned long g_heapbase and is
+	 * exported from here only because of its coupling to LCO
+	 * above.
+	 */
+
+	.data
+	.align	4
+	.globl	g_heapbase
+	.type	g_heapbase, object
+g_heapbase:
+	.long	_ebss+CONFIG_PROC_STACK_SIZE
+	.size	g_heapbase, .-g_heapbase
+
+	.end
+
diff --git a/nuttx/arch/arm/src/common/up_prefetchabort.c b/nuttx/arch/arm/src/common/up_prefetchabort.c
new file mode 100644
index 000000000..343c02c87
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_prefetchabort.c
@@ -0,0 +1,81 @@
+/************************************************************
+ * common/up_prefetchabort.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <nuttx/irq.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/* Output debug info if stack dump is selected -- even if 
+ * debug is not selected.
+ */
+
+#ifdef CONFIG_ARCH_STACKDUMP
+# undef  lldbg
+# define lldbg lib_lowprintf
+#endif
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_prefetchabort
+ ************************************************************/
+
+void up_prefetchabort(uint32 *regs)
+{
+  lldbg("Prefetch abort at 0x%x\n", regs[REG_PC]);
+  current_regs = regs;
+  PANIC(OSERR_ERREXCEPTION);
+}
diff --git a/nuttx/arch/arm/src/common/up_releasepending.c b/nuttx/arch/arm/src/common/up_releasepending.c
new file mode 100644
index 000000000..7f8016d53
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_releasepending.c
@@ -0,0 +1,131 @@
+/************************************************************
+ * common/up_releasepending.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_release_pending
+ *
+ * Description:
+ *   Release and ready-to-run tasks that have
+ *   collected in the pending task list.  This can call a
+ *   context switch if a new task is placed at the head of
+ *   the ready to run list.
+ *
+ ************************************************************/
+
+void up_release_pending(void)
+{
+  _TCB *rtcb = (_TCB*)g_readytorun.head;
+
+  lldbg("From TCB=%p\n", rtcb);
+
+  /* Merge the g_pendingtasks list into the g_readytorun task list */
+
+  /* sched_lock(); */
+  if (sched_mergepending())
+    {
+      /* The currently active task has changed!  We will need to
+       * switch contexts.  First check if we are operating in
+       * interrupt context:
+       */
+
+      if (current_regs)
+        {
+          /* Yes, then we have to do things differently.
+           * Just copy the current_regs into the OLD rtcb.
+           */
+
+           up_copystate(rtcb->xcp.regs, current_regs);
+
+          /* Restore the exception context of the rtcb at the (new) head 
+           * of the g_readytorun task list.
+           */
+
+          rtcb = (_TCB*)g_readytorun.head;
+          lldbg("New Active Task TCB=%p\n", rtcb);
+
+          /* Then switch contexts */
+
+          up_copystate(current_regs, rtcb->xcp.regs);
+        }
+
+      /* Copy the exception context into the TCB of the task that
+       * was currently active. if up_saveusercontext returns a non-zero
+       * value, then this is really the previously running task 
+       * restarting!
+       */
+
+      else if (!up_saveusercontext(rtcb->xcp.regs))
+        {
+          /* Restore the exception context of the rtcb at the (new) head 
+           * of the g_readytorun task list.
+           */
+
+          rtcb = (_TCB*)g_readytorun.head;
+          lldbg("New Active Task TCB=%p\n", rtcb);
+
+           /* Then switch contexts */
+
+          up_fullcontextrestore(rtcb->xcp.regs);
+        }
+    }
+}
diff --git a/nuttx/arch/arm/src/common/up_releasestack.c b/nuttx/arch/arm/src/common/up_releasestack.c
new file mode 100644
index 000000000..b00b9ab0c
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_releasestack.c
@@ -0,0 +1,78 @@
+/************************************************************
+ * common/up_releasestack.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Types
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+/************************************************************
+ * Global Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_release_stack
+ *
+ * Description:
+ *   A task has been stopped. Free all stack
+ *   related resources retained int the defunct TCB.
+ *
+ ************************************************************/
+
+void up_release_stack(_TCB *dtcb)
+{
+  if (dtcb->stack_alloc_ptr)
+    {
+      sched_free(dtcb->stack_alloc_ptr);
+      dtcb->stack_alloc_ptr = NULL;
+    }
+
+  dtcb->adj_stack_size = 0;
+}
diff --git a/nuttx/arch/arm/src/common/up_reprioritizertr.c b/nuttx/arch/arm/src/common/up_reprioritizertr.c
new file mode 100644
index 000000000..1f589b73f
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_reprioritizertr.c
@@ -0,0 +1,179 @@
+/************************************************************
+ * common/up_reprioritizertr.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_reprioritize_rtr
+ *
+ * Description:
+ *   Called when the priority of a running or
+ *   ready-to-run task changes and the reprioritization will 
+ *   cause a context switch.  Two cases:
+ *
+ *   1) The priority of the currently running task drops and the next
+ *      task in the ready to run list has priority.
+ *   2) An idle, ready to run task's priority has been raised above the
+ *      the priority of the current, running task and it now has the
+ *      priority.
+ *
+ * Inputs:
+ *   tcb: The TCB of the task that has been reprioritized
+ *   priority: The new task priority
+ *
+ ************************************************************/
+
+void up_reprioritize_rtr(_TCB *tcb, ubyte priority)
+{
+  /* Verify that the caller is sane */
+
+  if (tcb->task_state < FIRST_READY_TO_RUN_STATE ||
+      tcb->task_state > LAST_READY_TO_RUN_STATE ||
+      priority < SCHED_PRIORITY_MIN || 
+      priority > SCHED_PRIORITY_MAX)
+    {
+       PANIC(OSERR_BADREPRIORITIZESTATE);
+    }
+  else
+    {
+      _TCB *rtcb = (_TCB*)g_readytorun.head;
+      boolean switch_needed;
+
+      lldbg("TCB=%p PRI=%d\n", tcb, priority);
+
+      /* Remove the tcb task from the ready-to-run list.
+       * sched_removereadytorun will return TRUE if we just
+       * remove the head of the ready to run list.
+       */
+
+      switch_needed = sched_removereadytorun(tcb);
+
+      /* Setup up the new task priority */
+
+      tcb->sched_priority = (ubyte)priority;
+
+      /* Return the task to the specified blocked task list.
+       * sched_addreadytorun will return TRUE if the task was
+       * added to the new list.  We will need to perform a context
+       * switch only if the EXCLUSIVE or of the two calls is non-zero
+       * (i.e., one and only one the calls changes the head of the
+       * ready-to-run list).
+       */
+
+      switch_needed ^= sched_addreadytorun(tcb);
+
+      /* Now, perform the context switch if one is needed */
+
+      if (switch_needed)
+        {
+          /* If we are going to do a context switch, then now is the right
+           * time to add any pending tasks back into the ready-to-run list.
+           * task list now
+           */
+
+          if (g_pendingtasks.head)
+            {
+              sched_mergepending();
+            }
+
+         /* Are we in an interrupt handler? */
+
+          if (current_regs)
+            {
+              /* Yes, then we have to do things differently.
+               * Just copy the current_regs into the OLD rtcb.
+               */
+
+               up_copystate(rtcb->xcp.regs, current_regs);
+
+              /* Restore the exception context of the rtcb at the (new) head 
+               * of the g_readytorun task list.
+               */
+
+              rtcb = (_TCB*)g_readytorun.head;
+              lldbg("New Active Task TCB=%p\n", rtcb);
+
+              /* Then switch contexts */
+
+              up_copystate(current_regs, rtcb->xcp.regs);
+            }
+
+          /* Copy the exception context into the TCB at the (old) head of the
+           * g_readytorun Task list. if up_saveusercontext returns a non-zero
+           * value, then this is really the previously running task restarting!
+           */
+
+          else if (!up_saveusercontext(rtcb->xcp.regs))
+            {
+              /* Restore the exception context of the rtcb at the (new) head 
+               * of the g_readytorun task list.
+               */
+
+              rtcb = (_TCB*)g_readytorun.head;
+              lldbg("New Active Task TCB=%p\n", rtcb);
+
+              /* Then switch contexts */
+
+              up_fullcontextrestore(rtcb->xcp.regs);
+            }
+        }
+    }
+}
diff --git a/nuttx/arch/arm/src/common/up_saveusercontext.S b/nuttx/arch/arm/src/common/up_saveusercontext.S
new file mode 100644
index 000000000..cdaf7cc25
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_saveusercontext.S
@@ -0,0 +1,119 @@
+/**************************************************************************
+ * common/up_saveusercontext.S
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ **************************************************************************/
+
+/**************************************************************************
+ * Included Files
+ **************************************************************************/
+
+#include <nuttx/irq.h>
+#include "up_internal.h"
+
+/**************************************************************************
+ * Private Definitions
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Types
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Function Prototypes
+ **************************************************************************/
+
+/**************************************************************************
+ * Global Variables
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Variables
+ **************************************************************************/
+
+/**************************************************************************
+ * Private Functions
+ **************************************************************************/
+
+/**************************************************************************
+ * Public Functions
+ **************************************************************************/
+
+/**************************************************************************
+ * Name: up_saveusercontext
+ **************************************************************************/
+
+	.text
+	.globl	up_saveusercontext
+	.type	up_saveusercontext, function
+up_saveusercontext:
+	/* On entry, a1 (r0) holds address of struct xcptcontext.
+	 * Offset to the user region.
+	 */
+
+	/* Make sure that the return value will be non-zero (the
+	 * value of the other volatile registers don't matter --
+	 * r1-r3, ip).  This function is called throught the
+	 * noraml C calling conventions and the values of these
+	 * registers cannot be assumed at the point of setjmp
+	 * return.
+	 */
+
+        mov	ip, #1
+	str	ip, [r0, #(4*REG_R0)]
+
+	/* Save the volatile registers (plus r12 which really
+	 * doesn't need to be saved)
+	 */
+
+	add	r1, r0, #(4*REG_R4)
+	stmia	r1, {r4-r14}
+
+	/* Save the current cpsr */
+
+	mrs	r2, cpsr		/* R3 = CPSR value */
+	add	r1, r0, #(4*REG_CPSR)
+	str	r2, [r1]
+
+	/* Finally save the return address as the PC so that we
+	 * return to the exit from this function.
+	 */
+
+        add	r1, r0, #(4*REG_PC)
+	str	lr, [r1]
+
+	/* Return 0 */
+
+	mov	r0, #0		/* Return value == 0 */
+	mov	pc, lr		/* Return */
+	.size	up_saveusercontext, . - up_saveusercontext
+
diff --git a/nuttx/arch/arm/src/common/up_schedulesigaction.c b/nuttx/arch/arm/src/common/up_schedulesigaction.c
new file mode 100644
index 000000000..6b56cc3b6
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_schedulesigaction.c
@@ -0,0 +1,190 @@
+/************************************************************
+ * common/up_schedulesigaction.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+#include "up_arch.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_schedule_sigaction
+ *
+ * Description:
+ *   This function is called by the OS when one or more
+ *   signal handling actions have been queued for execution.
+ *   The architecture specific code must configure things so
+ *   that the 'igdeliver' callback is executed on the thread
+ *   specified by 'tcb' as soon as possible.
+ *
+ *   This function may be called from interrupt handling logic.
+ *
+ *   This operation should not cause the task to be unblocked
+ *   nor should it cause any immediate execution of sigdeliver.
+ *   Typically, a few cases need to be considered:
+ *
+ *   (1) This function may be called from an interrupt handler
+ *       During interrupt processing, all xcptcontext structures
+ *       should be valid for all tasks.  That structure should
+ *       be modified to invoke sigdeliver() either on return
+ *       from (this) interrupt or on some subsequent context
+ *       switch to the recipient task.
+ *   (2) If not in an interrupt handler and the tcb is NOT
+ *       the currently executing task, then again just modify
+ *       the saved xcptcontext structure for the recipient
+ *       task so it will invoke sigdeliver when that task is
+ *       later resumed.
+ *   (3) If not in an interrupt handler and the tcb IS the
+ *       currently executing task -- just call the signal
+ *       handler now.
+ *
+ ************************************************************/
+
+void up_schedule_sigaction(_TCB *tcb, sig_deliver_t sigdeliver)
+{
+  /* Refuse to handle nested signal actions */
+
+  dbg("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
+
+  if (!tcb->xcp.sigdeliver)
+    {
+      irqstate_t flags;
+
+      /* Make sure that interrupts are disabled */
+
+      flags = irqsave();
+
+      /* First, handle some special cases when the signal is
+       * being delivered to the currently executing task.
+       */
+
+      dbg("rtcb=0x%p current_regs=0x%p\n", g_readytorun.head, current_regs);
+
+      if (tcb == (_TCB*)g_readytorun.head)
+        {
+          /* CASE 1:  We are not in an interrupt handler and
+           * a task is signalling itself for some reason.
+           */
+
+          if (!current_regs)
+            {
+              /* In this case just deliver the signal now. */
+
+              sigdeliver(tcb);
+            }
+
+          /* CASE 2:  We are in an interrupt handler AND the
+           * interrupted task is the same as the one that
+           * must receive the signal, then we will have to modify
+           * the return state as well as the state in the TCB.
+           */
+
+          else
+            {
+              /* Save the return lr and cpsr and one scratch register
+               * These will be restored by the signal trampoline after
+               * the signals have been delivered.
+               */
+
+              tcb->xcp.sigdeliver    = sigdeliver;
+              tcb->xcp.saved_pc      = current_regs[REG_PC];
+              tcb->xcp.saved_cpsr    = current_regs[REG_CPSR];
+
+              /* Then set up to vector to the trampoline with interrupts
+               * disabled
+               */
+
+              current_regs[REG_PC]    = (uint32)up_sigdeliver;
+              current_regs[REG_CPSR]  = SVC_MODE | PSR_I_BIT | PSR_F_BIT;
+
+              /* And make sure that the saved context in the TCB
+               * is the same as the interrupt return context.
+               */
+
+              up_copystate(tcb->xcp.regs, current_regs);
+            }
+        }
+
+      /* Otherwise, we are (1) signaling a task is not running
+       * from an interrupt handler or (2) we are not in an
+       * interrupt handler and the running task is signalling
+       * some non-running task.
+       */
+
+      else
+        {
+          /* Save the return lr and cpsr and one scratch register
+           * These will be restored by the signal trampoline after
+           * the signals have been delivered.
+           */
+
+          tcb->xcp.sigdeliver    = sigdeliver;
+          tcb->xcp.saved_pc      = tcb->xcp.regs[REG_PC];
+          tcb->xcp.saved_cpsr    = tcb->xcp.regs[REG_CPSR];
+
+          /* Then set up to vector to the trampoline with interrupts
+           * disabled
+           */
+
+          tcb->xcp.regs[REG_PC]   = (uint32)up_sigdeliver;
+          tcb->xcp.regs[REG_CPSR] = SVC_MODE | PSR_I_BIT | PSR_F_BIT;
+        }
+
+      irqrestore(flags);
+    }
+}
diff --git a/nuttx/arch/arm/src/common/up_sigdeliver.c b/nuttx/arch/arm/src/common/up_sigdeliver.c
new file mode 100644
index 000000000..e6a0dfd89
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_sigdeliver.c
@@ -0,0 +1,135 @@
+/************************************************************
+ * common/up_sigdeliver.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/irq.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+#include "up_arch.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_sigdeliver
+ *
+ * Description:
+ *   This is the a signal handling trampoline.  When a
+ *   signal action was posted.  The task context was mucked
+ *   with and forced to branch to this location with interrupts
+ *   disabled.
+ *
+ ************************************************************/
+
+void up_sigdeliver(void)
+{
+  _TCB  *rtcb = (_TCB*)g_readytorun.head;
+  uint32 regs[XCPTCONTEXT_REGS];
+  sig_deliver_t sigdeliver;
+
+  /* Save the errno.  This must be preserved throughout the
+   * signal handling so that the the user code final gets
+   * the correct errno value (probably EINTR).
+   */
+
+  int saved_errno = rtcb->errno;
+
+  up_ledon(LED_SIGNAL);
+
+  dbg("rtcb=%p sigdeliver=%p sigpendactionq.head=%p\n",
+       rtcb, rtcb->xcp.sigdeliver, rtcb->sigpendactionq.head);
+  ASSERT(rtcb->xcp.sigdeliver != NULL);
+
+  /* Save the real return state on the stack. */
+
+  up_copystate(regs, rtcb->xcp.regs);
+  regs[REG_PC]   = rtcb->xcp.saved_pc;
+  regs[REG_CPSR] = rtcb->xcp.saved_cpsr;
+
+  /* Get a local copy of the sigdeliver function pointer.
+   * we do this so that we can nullify the sigdeliver
+   * function point in the TCB and accept more signal
+   * deliveries while processing the current pending
+   * signals.
+   */
+
+  sigdeliver           = rtcb->xcp.sigdeliver;
+  rtcb->xcp.sigdeliver = NULL;
+
+  /* Then restore the task interrupt statat. */
+
+  irqrestore(regs[REG_CPSR]);
+
+  /* Deliver the signals */
+
+  sigdeliver(rtcb);
+
+  /* Output any debug messaged BEFORE restoreing errno
+   * (becuase they may alter errno), then restore the
+   * original errno that is needed by the user logic
+   * (it is probably EINTR).
+   */
+
+  dbg("Resuming\n");
+  rtcb->errno = saved_errno;
+
+  /* Then restore the correct state for this thread of
+   * execution.
+   */
+
+  up_ledoff(LED_SIGNAL);
+  up_fullcontextrestore(regs);
+}
diff --git a/nuttx/arch/arm/src/common/up_syscall.c b/nuttx/arch/arm/src/common/up_syscall.c
new file mode 100644
index 000000000..47a7150be
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_syscall.c
@@ -0,0 +1,94 @@
+/************************************************************
+ * common/up_syscall.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include "up_arch.h"
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/* Output debug info if stack dump is selected -- even if 
+ * debug is not selected.
+ */
+
+#ifdef CONFIG_ARCH_STACKDUMP
+# undef  lldbg
+# define lldbg lib_lowprintf
+#endif
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * vectors
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_syscall
+ *
+ * Description:
+ *   SWI interrupts will vection here with insn=the SWI
+ *   instruction and xcp=the interrupt context
+ *
+ *   The handler may get the SWI number be de-referencing
+ *   the return address saved in the xcp and decoding
+ *   the SWI instruction
+ *
+ ************************************************************/
+
+void up_syscall(uint32 *regs)
+{
+  lldbg("Syscall from 0x%x\n", regs[REG_PC]);
+  current_regs = regs;
+  PANIC(OSERR_ERREXCEPTION);
+}
diff --git a/nuttx/arch/arm/src/common/up_unblocktask.c b/nuttx/arch/arm/src/common/up_unblocktask.c
new file mode 100644
index 000000000..97c416182
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_unblocktask.c
@@ -0,0 +1,161 @@
+/************************************************************
+ * common/up_unblocktask.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Private Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Funtions
+ ************************************************************/
+
+/************************************************************
+ * Public Funtions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_unblock_task
+ *
+ * Description:
+ *   A task is currently in an inactive task list
+ *   but has been prepped to execute.  Move the TCB to the
+ *   ready-to-run list, restore its context, and start execution.
+ *
+ * Inputs:
+ *   tcb: Refers to the tcb to be unblocked.  This tcb is
+ *     in one of the waiting tasks lists.  It must be moved to
+ *     the ready-to-run list and, if it is the highest priority
+ *     ready to run taks, executed.
+ *
+ ************************************************************/
+
+void up_unblock_task(_TCB *tcb)
+{
+  /* Verify that the context switch can be performed */
+
+  if ((tcb->task_state < FIRST_BLOCKED_STATE) ||
+      (tcb->task_state > LAST_BLOCKED_STATE))
+    {
+      PANIC(OSERR_BADUNBLOCKSTATE);
+    }
+  else
+    {
+      _TCB *rtcb = (_TCB*)g_readytorun.head;
+
+      lldbg("Unblocking TCB=%p\n", tcb);
+
+      /* Remove the task from the blocked task list */
+
+      sched_removeblocked(tcb);
+
+      /* Reset its timeslice.  This is only meaningful for round
+       * robin tasks but it doesn't here to do it for everything
+       */
+
+#if CONFIG_RR_INTERVAL > 0
+      tcb->timeslice = CONFIG_RR_INTERVAL;
+#endif
+
+      /* Add the task in the correct location in the prioritized
+       * g_readytorun task list
+       */
+
+      if (sched_addreadytorun(tcb))
+        {
+          /* The currently active task has changed! We need to do
+           * a context switch to the new task.
+           *
+           * Are we in an interrupt handler? 
+           */
+
+          if (current_regs)
+            {
+              /* Yes, then we have to do things differently.
+               * Just copy the current_regs into the OLD rtcb.
+               */
+
+               up_copystate(rtcb->xcp.regs, current_regs);
+
+              /* Restore the exception context of the rtcb at the (new) head 
+               * of the g_readytorun task list.
+               */
+
+              rtcb = (_TCB*)g_readytorun.head;
+              lldbg("New Active Task TCB=%p\n", rtcb);
+
+              /* Then switch contexts */
+
+              up_copystate(current_regs, rtcb->xcp.regs);
+            }
+
+          /* We are not in an interrupt handler.  Copy the user C context
+           * into the TCB of the task that was previously active.  if 
+           * up_saveusercontext returns a non-zero value, then this is really the
+           * previously running task restarting!
+           */
+
+          else if (!up_saveusercontext(rtcb->xcp.regs))
+            {
+              /* Restore the exception context of the new task that is ready to
+               * run (probably tcb).  This is the new rtcb at the head of the
+               * g_readytorun task list.
+               */
+
+              rtcb = (_TCB*)g_readytorun.head;
+              lldbg("New Active Task TCB=%p\n", rtcb);
+
+              /* Then switch contexts */
+
+              up_fullcontextrestore(rtcb->xcp.regs);
+            }
+        }
+    }
+}
diff --git a/nuttx/arch/arm/src/common/up_undefinedinsn.c b/nuttx/arch/arm/src/common/up_undefinedinsn.c
new file mode 100644
index 000000000..261118ec7
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_undefinedinsn.c
@@ -0,0 +1,79 @@
+/************************************************************
+ * common/up_undefinedinsn.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include "os_internal.h"
+#include "up_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/* Output debug info if stack dump is selected -- even if 
+ * debug is not selected.
+ */
+
+#ifdef CONFIG_ARCH_STACKDUMP
+# undef  lldbg
+# define lldbg lib_lowprintf
+#endif
+
+/************************************************************
+ * Private Data
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_undefinedinsn
+ ************************************************************/
+
+void up_undefinedinsn(uint32 *regs)
+{
+  lldbg("Undefined instruction at 0x%x\n", regs[REG_PC]);
+  current_regs = regs;
+  PANIC(OSERR_UNDEFINEDINSN);
+}
diff --git a/nuttx/arch/arm/src/common/up_usestack.c b/nuttx/arch/arm/src/common/up_usestack.c
new file mode 100644
index 000000000..2da044182
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_usestack.c
@@ -0,0 +1,118 @@
+/************************************************************
+ * common/up_usestack.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <debug.h>
+#include <nuttx/kmalloc.h>
+#include <nuttx/arch.h>
+#include "up_internal.h"
+
+/************************************************************
+ * Private Types
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+/************************************************************
+ * Global Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_use_stack
+ *
+ * Description:
+ *   Setup up stack-related information in the TCB
+ *   using pre-allocated stack memory
+ *
+ *   The following TCB fields must be initialized:
+ *   adj_stack_size: Stack size after adjustment for hardware,
+ *     processor, etc.  This value is retained only for debug
+ *     purposes.
+ *   stack_alloc_ptr: Pointer to allocated stack
+ *   adj_stack_ptr: Adjusted stack_alloc_ptr for HW.  The
+ *     initial value of the stack pointer.
+ *
+ * Inputs:
+ *   tcb: The TCB of new task
+ *   stack_size:  The allocated stack size.
+ *
+ ************************************************************/
+
+STATUS up_use_stack(_TCB *tcb, void *stack, size_t stack_size)
+{
+  size_t top_of_stack;
+  size_t size_of_stack;
+
+  if (tcb->stack_alloc_ptr)
+    {
+      sched_free(tcb->stack_alloc_ptr);
+    }
+
+  /* Save the stack allocation */
+
+  tcb->stack_alloc_ptr = stack;
+
+  /* The Arm7Tdmi uses a push-down stack:  the stack grows
+   * toward loweraddresses in memory.  The stack pointer
+   * register, points to the lowest, valid work address
+   * (the "top" of the stack).  Items on the stack are
+   * referenced as positive word offsets from sp.
+   */
+
+  top_of_stack = (uint32)tcb->stack_alloc_ptr + stack_size - 4;
+
+  /* The Arm7Tdmi stack must be aligned at word (4 byte)
+   * boundaries. If necessary top_of_stack must be rounded
+   * down to the next boundary
+   */
+
+  top_of_stack &= ~3;
+  size_of_stack = top_of_stack - (uint32)tcb->stack_alloc_ptr + 4;
+
+  /* Save the adjusted stack values in the _TCB */
+
+  tcb->adj_stack_size = top_of_stack;
+  tcb->adj_stack_size = size_of_stack;
+
+  return OK;
+}
diff --git a/nuttx/arch/arm/src/common/up_vectors.S b/nuttx/arch/arm/src/common/up_vectors.S
new file mode 100644
index 000000000..648060218
--- /dev/null
+++ b/nuttx/arch/arm/src/common/up_vectors.S
@@ -0,0 +1,449 @@
+/********************************************************************
+ * common/up_vectors.S
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ********************************************************************/
+
+/********************************************************************
+ * Included Files
+ ********************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/irq.h>
+#include "up_arch.h"
+
+/********************************************************************
+ * Definitions
+ ********************************************************************/
+
+/********************************************************************
+ * Global Data
+ ********************************************************************/
+
+	.data
+g_irqtmp:
+	.word	0		/* Saved lr */
+	.word	0		/* Saved spsr */
+g_undeftmp:
+	.word	0		/* Saved lr */
+	.word	0		/* Saved spsr */
+g_aborttmp:
+	.word	0		/* Saved lr */
+	.word	0		/* Saved spsr */
+
+/********************************************************************
+ * Assembly Macros
+ ********************************************************************/
+
+/********************************************************************
+ * Private Functions
+ ********************************************************************/
+
+	.text
+
+/********************************************************************
+ * Public Functions
+ ********************************************************************/
+
+	.text
+
+/********************************************************************
+ * Name: up_vectorirq
+ *
+ * Description:
+ *   Interrupt excetpion. Entered in IRQ mode with spsr = SVC
+ *   CPSR, lr = SVC PC
+ ********************************************************************/
+
+	.globl	up_vectorirq
+	.type	up_vectorirq, %function
+up_vectorirq:
+	/* On entry, we are in IRQ mode.  We are free to use
+	 * the IRQ mode r13 and r14.
+         *
+	 */
+
+	ldr	r13, .Lirqtmp
+	sub	lr, lr, #4
+	str	lr, [r13]			@ save lr_IRQ
+	mrs	lr, spsr
+	str	lr, [r13, #4]			@ save spsr_IRQ
+
+	/* Then switch back to SVC mode */
+
+	bic	lr, lr, #MODE_MASK	/* Keep F and T bits */
+	orr	lr, lr, #(SVC_MODE | PSR_I_BIT)
+	msr	cpsr_c, lr		/* Switch to SVC mode */
+
+	/* Create a context structure.  First set aside a stack frame
+	 * and store r0-r12 into the frame.
+	 */
+
+	sub	sp, sp, #XCPTCONTEXT_SIZE
+	stmia	sp, {r0-r12}		/* Save the SVC mode regs */
+
+	/* Get the correct values of r13(sp) and r14(lr) in r1 and r2 */
+
+	add	r1, sp, #XCPTCONTEXT_SIZE
+	mov	r2, r14
+
+	/* Get the values for r15(pc) and CPSR in r3 and r4 */
+
+	ldr	r0, .Lirqtmp		/* Points to temp storage */
+	ldmia	r0, {r3, r4}		/* Recover r1=lr_IRQ, r2=spsr_IRQ */
+
+	add	r0, sp, #(4*REG_SP)	/* Offset to pc, cpsr storage */
+	stmia	r0, {r1-r4}
+
+	/* Then call the IRQ handler with interrupts disabled. */
+
+	mov	fp, #0			/* Init frame pointer */
+	mov	r0, sp			/* Get r0=xcp */
+	bl	up_doirq		/* Call the handler */
+
+	/* Restore the CPSR, SVC modr registers and return */
+.Lnoirqset:
+	ldr	r0, [sp, #(4*REG_CPSR)]	/* Setup the SVC mode SPSR */
+	msr	spsr, r0
+	ldmia	sp, {r0-r15}^		/* Return */
+
+.Lirqtmp:
+	.word	g_irqtmp
+
+	.align	5
+
+/********************************************************************
+ * Function: up_vectorswi
+ * 
+ * Description:
+ *   SWI interrupt. We enter the SWI in SVC mode
+ ********************************************************************/
+
+	.globl	up_vectorswi
+	.type	up_vectorswi, %function
+up_vectorswi:
+
+	/* Create a context structure.  First set aside a stack frame
+	 * and store r0-r12 into the frame.
+	 */
+
+	sub	sp, sp, #XCPTCONTEXT_SIZE
+	stmia	sp, {r0-r12}		/* Save the SVC mode regs */
+
+	/* Get the correct values of r13(sp), r14(lr), r15(pc)
+	 * and CPSR in r1-r4 */
+
+	add	r1, sp, #XCPTCONTEXT_SIZE
+	mov	r2, r14			/* R14 is altered on return from SWI */
+	mov	r3, r14			/* Save r14 as the PC as well */
+	mrs	r4, spsr		/* Get the saved CPSR */
+
+	add	r0, sp, #(4*REG_SP)	/* Offset to pc, cpsr storage */
+	stmia	r0, {r1-r4}
+
+	/* Then call the SWI handler with interrupts disabled.
+	 * void up_syscall(struct xcptcontext *xcp)
+	 */
+
+	mov	fp, #0			/* Init frame pointer */
+	mov	r0, sp			/* Get r0=xcp */
+	bl	up_syscall		/* Call the handler */
+
+	/* Restore the CPSR, SVC modr registers and return */
+
+	ldr	r0, [sp, #(4*REG_CPSR)]	/* Setup the SVC mode SPSR */
+	msr	spsr, r0
+	ldmia	sp, {r0-r15}^		/* Return */
+
+	.align	5
+
+/********************************************************************
+ * Name: up_vectordata
+ *
+ * Description:
+ *   Data abort Exception dispatcher. Give control to data
+ *   abort handler.  This function is entered in ABORT mode
+ *   with spsr = SVC CPSR, lr = SVC PC
+ *
+ ********************************************************************/
+	
+	.globl	up_vectordata
+	.type	up_vectordata, %function
+up_vectordata:
+	/* On entry we are free to use the ABORT mode registers
+	 * r13 and r14
+	 */
+
+	ldr	r13, .Ldaborttmp	/* Points to temp storage */
+	sub	lr, lr, #8		/* Fixup return */
+	str	lr, [r13]		/* Save in temp storage */
+	mrs	lr, spsr		/* Get SPSR */
+	str	lr, [r13, #4]		/* Save in temp storage */
+
+	/* Then switch back to SVC mode */
+
+	bic	lr, lr, #MODE_MASK	/* Keep F and T bits */
+	orr	lr, lr, #(SVC_MODE | PSR_I_BIT)
+	msr	cpsr_c, lr		/* Switch to SVC mode */
+
+	/* Create a context structure.  First set aside a stack frame
+	 * and store r0-r12 into the frame.
+	 */
+
+	sub	sp, sp, #XCPTCONTEXT_SIZE
+	stmia	sp, {r0-r12}		/* Save the SVC mode regs */
+
+	/* Get the correct values of r13(sp) and r14(lr) in r1 and r2 */
+
+	add	r1, sp, #XCPTCONTEXT_SIZE
+	mov	r2, r14
+
+	/* Get the values for r15(pc) and CPSR in r3 and r4 */
+
+	ldr	r0, .Ldaborttmp		/* Points to temp storage */
+	ldmia	r0, {r3, r4}		/* Recover r1=lr_IRQ, r2=spsr_IRQ */
+
+	add	r0, sp, #(4*REG_SP)	/* Offset to pc, cpsr storage */
+	stmia	r0, {r1-r4}
+
+	/* Then call the data abort handler with interrupts disabled.
+	 * void up_dataabort(struct xcptcontext *xcp)
+	 */
+
+	mov	fp, #0			/* Init frame pointer */
+	mov	r0, sp			/* Get r0=xcp */
+	bl	up_dataabort		/* Call the handler */
+
+	/* Restore the CPSR, SVC modr registers and return */
+
+	ldr	r0, [sp, #(4*REG_CPSR)]	/* Setup the SVC mode SPSR */
+	msr	spsr_cxsf, r0
+	ldmia	sp, {r0-r15}^		/* Return */
+
+.Ldaborttmp:
+	.word	g_aborttmp
+
+	.align	5
+
+/********************************************************************
+ * Name: up_vectorprefetch
+ *
+ * Description:
+ *    Prefetch abort exception.  Entered in ABT mode with
+ *    spsr = SVC CPSR, lr = SVC PC
+ ********************************************************************/
+	
+	.globl	up_vectorprefetch
+	.type	up_vectorprefetch, %function
+up_vectorprefetch:
+	/* On entry we are free to use the ABORT mode registers
+	 * r13 and r14
+	 */
+
+	ldr	r13, .Lpaborttmp	/* Points to temp storage */
+	sub	lr, lr, #4		/* Fixup return */
+	str	lr, [r13]		/* Save in temp storage */
+	mrs	lr, spsr		/* Get SPSR */
+	str	lr, [r13, #4]		/* Save in temp storage */
+
+	/* Then switch back to SVC mode */
+
+	bic	lr, lr, #MODE_MASK	/* Keep F and T bits */
+	orr	lr, lr, #(SVC_MODE | PSR_I_BIT)
+	msr	cpsr_c, lr		/* Switch to SVC mode */
+
+	/* Create a context structure.  First set aside a stack frame
+	 * and store r0-r12 into the frame.
+	 */
+
+	sub	sp, sp, #XCPTCONTEXT_SIZE
+	stmia	sp, {r0-r12}		/* Save the SVC mode regs */
+
+	/* Get the correct values of r13(sp) and r14(lr) in r1 and r2 */
+
+	add	r1, sp, #XCPTCONTEXT_SIZE
+	mov	r2, r14
+
+	/* Get the values for r15(pc) and CPSR in r3 and r4 */
+
+	ldr	r0, .Lpaborttmp		/* Points to temp storage */
+	ldmia	r0, {r3, r4}		/* Recover r1=lr_IRQ, r2=spsr_IRQ */
+
+	add	r0, sp, #(4*REG_SP)	/* Offset to pc, cpsr storage */
+	stmia	r0, {r1-r4}
+
+	/* Then call the prefetch abort handler with interrupts disabled.
+	 * void up_prefetchabort(struct xcptcontext *xcp)
+	 */
+
+	mov	fp, #0			/* Init frame pointer */
+	mov	r0, sp			/* Get r0=xcp */
+	bl	up_prefetchabort	/* Call the handler */
+
+	/* Restore the CPSR, SVC modr registers and return */
+
+	ldr	r0, [sp, #(4*REG_CPSR)]	/* Setup the SVC mode SPSR */
+	msr	spsr_cxsf, r0
+	ldmia	sp, {r0-r15}^		/* Return */
+
+.Lpaborttmp:
+	.word	g_aborttmp
+
+	.align	5
+
+/********************************************************************
+ * Name: up_vectorundefinsn
+ *
+ * Description:
+ *   Undefined instruction entry exception.  Entered in
+ *   UND mode, spsr = SVC  CPSR, lr = SVC PC
+ *
+ ********************************************************************/
+	
+	.globl	up_vectorundefinsn
+	.type	up_vectorundefinsn, %function
+up_vectorundefinsn:
+	/* On entry we are free to use the UND mode registers
+	 * r13 and r14
+	 */
+
+	ldr	r13, .Lundeftmp		/* Points to temp storage */
+	str	lr, [r13]		/* Save in temp storage */
+	mrs	lr, spsr		/* Get SPSR */
+	str	lr, [r13, #4]		/* Save in temp storage */
+
+	/* Then switch back to SVC mode */
+
+	bic	lr, lr, #MODE_MASK	/* Keep F and T bits */
+	orr	lr, lr, #(SVC_MODE | PSR_I_BIT)
+	msr	cpsr_c, lr		/* Switch to SVC mode */
+
+	/* Create a context structure.  First set aside a stack frame
+	 * and store r0-r12 into the frame.
+	 */
+
+	sub	sp, sp, #XCPTCONTEXT_SIZE
+	stmia	sp, {r0-r12}		/* Save the SVC mode regs */
+
+	/* Get the correct values of r13(sp) and r14(lr) in r1 and r2 */
+
+	add	r1, sp, #XCPTCONTEXT_SIZE
+	mov	r2, r14
+
+	/* Get the values for r15(pc) and CPSR in r3 and r4 */
+
+	ldr	r0, .Lundeftmp		/* Points to temp storage */
+	ldmia	r0, {r3, r4}		/* Recover r1=lr_IRQ, r2=spsr_IRQ */
+
+	add	r0, sp, #(4*REG_SP)	/* Offset to pc, cpsr storage */
+	stmia	r0, {r1-r4}
+
+	/* Then call the undef insn handler with interrupts disabled.
+	 * void up_undefinedinsn(struct xcptcontext *xcp)
+	 */
+
+	mov	fp, #0			/* Init frame pointer */
+	mov	r0, sp			/* Get r0=xcp */
+	bl	up_undefinedinsn	/* Call the handler */
+
+	/* Restore the CPSR, SVC modr registers and return */
+
+	ldr	r0, [sp, #(4*REG_CPSR)]	/* Setup the SVC mode SPSR */
+	msr	spsr_cxsf, r0
+	ldmia	sp, {r0-r15}^		/* Return */
+
+.Lundeftmp:
+	.word	g_undeftmp
+
+	.align	5
+
+/********************************************************************
+ * Name: up_vectorfiq
+ *
+ * Description:
+ *   Shouldn't happen
+ ********************************************************************/
+
+	.globl	up_vectorfiq
+	.type	up_vectorfiq, %function
+up_vectorfiq:
+	subs	pc, lr, #4
+
+/********************************************************************
+ *  Name: up_vectoraddrexcption
+ *
+ * Description:
+ *   Shouldn't happen
+ *
+ ********************************************************************/
+
+	.globl	up_vectoraddrexcptn
+	.type	up_vectoraddrexcptn, %function
+up_vectoraddrexcptn:
+	b	up_vectoraddrexcptn
+
+/**************************************************************************
+ * Vector initialization block.
+ **************************************************************************/
+
+/* These will be relocated to VECTOR_BASE. */
+
+	.globl	_vector_start
+_vector_start:
+	ldr	pc, .Lresethandler		/* 0x00: Reset */
+	ldr	pc, .Lundefinedhandler		/* 0x04: Undefined instruction */
+	ldr	pc, .Lswihandler		/* 0x08: Software interrupt */
+	ldr	pc, .Lprefetchaborthandler	/* 0x0c: Prefetch abort */
+	ldr	pc, .Ldataaborthandler		/* 0x10: Data abort */
+	ldr	pc, .Laddrexcptnhandler		/* 0x14: Address exception */
+	ldr	pc, .Lirqhandler		/* 0x18: IRQ */
+	ldr	pc, .Lfiqhandler		/* 0x1c: FIQ */
+
+.Lresethandler:
+	.long   __start
+.Lundefinedhandler:
+	.long	up_vectorundefinsn
+.Lswihandler:
+	.long	up_vectorswi
+.Lprefetchaborthandler:
+	.long	up_vectorprefetch
+.Ldataaborthandler:
+	.long	up_vectordata
+.Laddrexcptnhandler:
+	.long	up_vectoraddrexcptn
+.Lirqhandler:
+	.long	up_vectorirq
+.Lfiqhandler:
+	.long	up_vectorfiq
+	.globl	_vector_end
+_vector_end:
+	.end