More paging changes

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@2868 42af7a65-404d-4744-a932-0658087f49c3

5 files changed, 270 insertions, 25 deletions

diff --git a/nuttx/arch/arm/src/arm/pg_macros.h b/nuttx/arch/arm/src/arm/pg_macros.h
new file mode 100644
index 000000000..bf79ba32a
--- /dev/null
+++ b/nuttx/arch/arm/src/arm/pg_macros.h
@@ -0,0 +1,197 @@
+/****************************************************************************
+ * arch/arm/src/arm/pg_macros.S
+ *
+ *   Copyright (C) 2010 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 NuttX 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 __ARCH_ARM_SRC_ARM_PG_MACROS_H
+#define __ARCH_ARM_SRC_ARM_PG_MACROS_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include "arm.h"
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Assembly Macros
+ ****************************************************************************/
+
+/* Write one L2 entry for a coarse page table entry.
+ *
+ * Inputs (unmodified):
+ *   ctab  - Register containing the address of the coarse page table
+ *   paddr - Physical address of the page to be mapped
+ *   vaddr - Virtual address of the page to be mapped
+ *   mmuflags - the MMU flags to use in the mapping
+ *
+ * Scratch registers (modified): tmp1, tmp2
+ */
+ 
+	.macro	wrl2coarse, ctab, paddr, vaddr, mmuflags, tmp1, tmp2
+	
+	/* Get tmp1 = (paddr | mmuflags), the value to write into the table */
+
+	orr	\tmp1, \mmuflags, \paddr
+
+	/* index  = (vaddr & 0x000ff000) >> 12
+	 * offset = (vaddr & 0x000ff000) >> 10
+	 */
+
+	and	\tmp2, \vaddr, #0x0000ff000
+
+	/* Write value into table at ofset */
+
+	str	\tmp1, [\ctab, \tmp2, lsr #10]
+	.endm
+
+/* Write one L1 entry for a coarse page table.
+ *
+ * Inputs (unmodified unless noted):
+ *   paddr - Physical address of the section (modified)
+ *   vaddr - Virtual address of the section
+ *   mmuflags - MMU flags to use in the section mapping
+ *
+ * Scratch registers (modified): tmp1, tmp2, tmp3
+ */
+
+	.macro	wrl1coarse, paddr, vaddr, mmuflags, tmp1, tmp2
+	/* tmp1 = the base of the L1 page table */
+
+   	ldr	\tmp1, =PGTABLE_BASE_VADDR
+
+	/* tmp2 = (paddr | mmuflags), the value to write into the page table */
+
+	orr	\paddr, \paddr, \mmuflags
+
+	/* Write the value into the table at the correc offset.
+	 * table index = vaddr >> 20, offset = index << 2
+	 */
+	
+	lsr	\tmp2, \vaddr, #20
+	str	\paddr, [\tmp1, \tmp2, lsl #2]
+	.endm
+
+/* Write one coarse L1 entry and all assocated L2 entries for a
+ * coarse page table.
+ *
+ * Inputs:
+ *   offset - coarse page table offset (unmodified)
+ *   paddr - Physical address of the section (modified)
+ *   vaddr - Virtual address of the section (modified)
+ *   npages - Number of pages to write in the section (modified)
+ *
+ * Scratch registers (modified): tmp1, tmp2, tmp3, tmp4, tmp5
+ *
+ * On return, paddr and vaddr refer to the beginning of the
+ * next section.
+ */
+	.macro	wrcoarse, offset, paddr, vaddr, npages, tmp1, tmp2, tmp3, tmp4
+
+	/* tmp1 = address of L2 table; tmp2 = MMU flags */
+
+	ldr	\tmp1, =PGTABLE_COARSE_BASE_VADDR
+	add	\tmp1, \offset, \paddr
+	ldr	\tmp2, =MMU_L2_VECTORFLAGS
+	b	2f
+1:
+	/* Write that L2 entry into the coarse page table */
+
+	wrl2coarse \tmp1, \paddr, \vaddr, \tmp2, \tmp3, \tmp4
+
+	/* Update the physical and virtual addresses that will
+	 * correspond to the next table entry.
+	 */
+
+	add	\paddr, \paddr, #4096
+	add	\vaddr, \vaddr, #4096
+2:
+	/* Check if all of the pages have been written.  If not, then
+	 * loop and write the next entry.
+	 */
+
+	sub	\npages, \npages, #1
+	cmn	\npages #1
+	bne	1b
+
+	/* Write the section entry that refers to this coarse page
+	 * table.
+	 */
+
+	ldr	\tmp1, =PGTABLE_COARSE_BASE_PADDR
+	ldr	\tmp2, =MMU_L1_VECTORFLAGS
+	add	\tmp1, \offset, \tmp1
+	wrl1coarse \tmp1, \vaddr, \tmp2, \tmp3, \tmp4
+	.endm
+
+/* Write several, contiguous coarse L1 page table entries (and all
+ * associated L2 page table entries).  As many entries will be
+ * written as many as needed to span npages.
+ *
+ * Inputs:
+ *   offset - coarse page table offset (modified)
+ *   paddr - Physical address of the section (modified)
+ *   vaddr - Virtual address of the section
+ *   npages - Number of pages to write in the section
+ *
+ * Scratch registers (modified): tmp1, tmp2, tmp3, tmp4, tmp5
+ */
+
+	.macro	wrsections, offset, paddr, vaddr, npages, tmp1, tmp2, tmp3, tmp4
+	b	2f
+1:
+	/* Select the number of coarse, 4Kb pages to write in this section.
+	 * This number will be 256 unless there are fewer than 256 pages
+	 * remaining to be mapped.
+	 */
+
+	cmp	\npages, #255		/* Check if <= 255 */
+	movls	\tmp1, \npages		/* YES.. tmp1 = npages */
+	movls	\npages, #0		/*       npages = 0 */
+	movhi	\tmp1, #256		/* NO..  tmp1 = 256 */
+	subhi	\npages, \npages, #256	/*       npages -= 256 */
+
+	/* Write the L2 entries for this section */
+
+	wrcoarse \offset, \paddr, \vaddr, \tmp1, \tmp1, \tmp2, \tmp3, \tmp4
+	add	\offset, \offset, #1024
+2:
+	cmp	\npages, #0
+	bne	1b
+	.endm
+#endif /* __ARCH_ARM_SRC_ARM_PG_MACROS_H */
diff --git a/nuttx/arch/arm/src/arm/up_dataabort.c b/nuttx/arch/arm/src/arm/up_dataabort.c
index 52a595d6d..ecad23b30 100644
--- a/nuttx/arch/arm/src/arm/up_dataabort.c
+++ b/nuttx/arch/arm/src/arm/up_dataabort.c
@@ -133,7 +133,7 @@ void up_dataabort(uint32_t *regs, uint32_t far, uint32_t fsr)
    * (It has not yet been saved in the register context save area).
    */
  
-  if (far < CONFIG_PAGING_PAGEDBASE || far >= CONFIG_PAGING_PAGEDEND)
+  if (far < PG_PAGEDBASE || far >= PG_PAGEDEND)
     {
       goto segfault;
     }
diff --git a/nuttx/arch/arm/src/arm/up_head.S b/nuttx/arch/arm/src/arm/up_head.S
index 57bce742c..cdb6eff7a 100644
--- a/nuttx/arch/arm/src/arm/up_head.S
+++ b/nuttx/arch/arm/src/arm/up_head.S
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/arm/up_head.S
  *
- *   Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007, 2009-2010 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -45,7 +45,7 @@
 #include "up_arch.h"
 
 /**********************************************************************************
- * Conditional Compilation
+ * Configuration
  **********************************************************************************/
 
 #undef ALIGNMENT_TRAP
@@ -94,22 +94,33 @@
  * Definitions
  ****************************************************************************/
 
-/* EXE_NSECTIONS determines the number of 1Mb pages to map for the executable
- * address region.  This is based on CONFIG_DRAM_SIZE.  For most ARM9
- * architectures, CONFIG_DRAM_SIZE describes the size of installed SDRAM.
+/* RX_NSECTIONS determines the number of 1Mb sections to map for the
+ * Read/eXecute address region.  This is based on CONFIG_DRAM_SIZE.  For most
+ * ARM9 architectures, CONFIG_DRAM_SIZE describes the size of installed SDRAM.
  * But for other architectures, this might refer to the size of FLASH or
  * SRAM regions. (bad choice of naming).
  */
 
-#define EXE_NSECTIONS ((CONFIG_DRAM_SIZE+0x000fffff) >> 20)
+#define RX_NSECTIONS ((CONFIG_DRAM_SIZE+0x000fffff) >> 20)
+
+/* If CONFIG_PAGING is defined, then
+ * - RX_NPAGES determines the number of pages of size PAGESIZE that
+ *   are required to span the locked, Read/eXecute .text region.
+ * - RW_NPAGES determines the number of pages of size PAGESIZE this
+ *   are required to span the Read/Write data region.
+ */
+
+#ifdef CONFIG_PAGING
+#  define RX_NPAGES  CONFIG_PAGING_LOCKEDPAGES
+#endif
 
 /****************************************************************************
  * 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.
+/* 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
@@ -168,7 +179,7 @@ __start:
 	 * this startup logic executing out of the physical address space.  This
 	 * identity mapping will be removed by .Lvstart (see below).
 	 */
-#warning "We need to do things differently here if the .text region is smaller or if CONFIG_PAGING"
+
 	mksection r0, r4			/* r0=phys. base section */
 	ldr	r1, .LCmmuflags			/* FLGS=MMU_MEMFLAGS */
 	add	r3, r1, r0			/* r3=flags + base */
@@ -335,7 +346,7 @@ __start:
 	/* Now setup the pagetables for our normal SDRAM mappings mapped region.
 	 * We round NUTTX_START_VADDR down to the nearest megabyte boundary.
 	 */
-#warning "We need to do things differently here if the .text region is smaller or if CONFIG_PAGING"
+
 	ldr	r1, .LCmmuflags			/* FLGS=MMU_MEMFLAGS */
 	add	r3, r3, r1			/* r3=flags + base */
 
@@ -346,11 +357,11 @@ __start:
 	add	r0, r0, #(NUTTX_START_VADDR & 0x00f00000) >> 18
 	str	r3, [r0], #4
 
-	/* Now map the remaining EXE_NSECTIONS-1 sections of the executable
+	/* Now map the remaining RX_NSECTIONS-1 sections of the executable
 	 * memory region.
 	 */
 
-	.rept	EXE_NSECTIONS-1
+	.rept	RX_NSECTIONS-1
 	add	r3, r3, #SECTION_SIZE
 	str	r3, [r0], #4
 	.endr
diff --git a/nuttx/arch/arm/src/arm/up_prefetchabort.c b/nuttx/arch/arm/src/arm/up_prefetchabort.c
index 3572165b8..b3ea3cba3 100644
--- a/nuttx/arch/arm/src/arm/up_prefetchabort.c
+++ b/nuttx/arch/arm/src/arm/up_prefetchabort.c
@@ -117,8 +117,7 @@ void up_prefetchabort(uint32_t *regs)
    * virtual addresses.
    */
 
-  if (regs[REG_R15] >= CONFIG_PAGING_PAGEDBASE &&
-      regs[REG_R15] <  CONFIG_PAGING_PAGEDEND)
+  if (regs[REG_R15] >= PG_PAGEDBASE && regs[REG_R15] < PG_PAGEDEND)
     {
       /* Save the offending PC as the fault address in the TCB of the currently
        * executing task.  This value is, of course, already known in regs[REG_R15],
diff --git a/nuttx/include/nuttx/page.h b/nuttx/include/nuttx/page.h
index a279dcc47..ea1490c7e 100755
--- a/nuttx/include/nuttx/page.h
+++ b/nuttx/include/nuttx/page.h
@@ -54,22 +54,60 @@
 
 /* Configuration ************************************************************/
 /* CONFIG_PAGING_PAGESIZE - The size of one managed page.  This must be a
- *   value supported by the processor's memory management unit.
- * CONFIG_PAGING_NLOCKED - This is the number of locked pages in the memory
- *   map.  The locked address region will then be from:
+ *   value supported by the processor's memory management unit.  The
+ *   following may need to be extended to support additional page sizes at
+ *   some point.
  */
 
-#define CONFIG_PAGING_LOCKEDBASE CONFIG_DRAM_VSTART
-#define CONFIG_PAGING_LOCKEDSIZE (CONFIG_PAGING_PAGESIZE*CONFIG_PAGING_NLOCKED)
-#define CONFIG_PAGING_LOCKEDEND  (CONFIG_PAGING_LOCKEDBASE + CONFIG_PAGING_LOCKEDSIZE)
+#if CONFIG_PAGING_PAGESIZE == 1024
+#  define PAGESIZE                 1024
+#  define PAGESHIFT                10
+#  define PAGEMASK                 0x000003ff
+#elif CONFIG_PAGING_PAGESIZE == 4096
+#  define PAGESIZE                 4096
+#  define PAGESHIFT                12
+#  define PAGEMASK                 0x00000fff
+#else
+#  error "Need extended definitions for CONFIG_PAGING_PAGESIZE"
+#endif
+
+/* Alignment macros */
+
+#define PG_ALIGNDOWN(addr)         ((addr) & ~PAGEMASK)
+#define PG_ALIGNUP(addr)           (((addr) + PAGEMASK) & ~PAGEMASK)
+
+/* CONFIG_PAGING_NLOCKED - This is the number of locked pages in the memory
+ *   map.  The size of locked address region will then be:
+ */
+
+#define PG_LOCKEDSIZE              (CONFIG_PAGING_NLOCKED << PAGESHIFT)
+
+/* PG_LOCKEDBASE - May be defined to determine the base address
+ * of the locked page regions (lowest in memory).  If PG_LOCKEDBASE
+ * is not defined, it will be set to CONFIG_DRAM_VSTART (i.e., assuming that
+ * the base address of the locked region is at the virtual address of the
+ * beginning of RAM).
+ */
+
+#ifdef CONFIG_PAGING_LOCKEDBASE
+#  define PG_LOCKEDBASE            CONFIG_PAGING_LOCKEDBASE
+#else
+#  define PG_LOCKEDBASE            CONFIG_DRAM_VSTART
+#endif
+
+#define PG_LOCKEDEND               (PG_LOCKEDBASE + PG_LOCKEDSIZE)
+
+#if (PG_LOCKEDBASE & PAGEMASK) != 0
+#  error "Base address of the locked region is not page aligned"
+#endif
 
 /* CONFIG_PAGING_NPAGES - The number of pages in the paged region of the
  *   memory map.  This paged region then begins and ends at:
  */
 
-#define CONFIG_PAGING_PAGEDBASE CONFIG_PAGING_LOCKEDEND
-#define CONFIG_PAGING_PAGEDSIZE (CONFIG_PAGING_PAGESIZE*CONFIG_PAGING_NPAGES)
-#define CONFIG_PAGING_PAGEDEND  (CONFIG_PAGING_PAGEDBASE + CONFIG_PAGING_PAGEDSIZE)
+#define PG_PAGEDSIZE               (CONFIG_PAGING_NPAGES << PAGESHIFT)
+#define PG_PAGEDBASE               PG_LOCKEDEND
+#define PG_PAGEDEND                (PG_PAGEDBASE + PG_PAGEDSIZE)
 
 /* CONFIG_PAGING_DEFPRIO - The default, minimum priority of the page fill
  *   worker thread.  The priority of the page fill work thread will be boosted