1 files changed, 231 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/lpc43xx/lpc43_start.c b/nuttx/arch/arm/src/lpc43xx/lpc43_start.c
new file mode 100644
index 000000000..76f4f8ca3
--- /dev/null
+++ b/nuttx/arch/arm/src/lpc43xx/lpc43_start.c
@@ -0,0 +1,231 @@
+/****************************************************************************
+ * arch/arm/src/lpc43xx/lpc43_start.c
+ * arch/arm/src/chip/lpc43_start.c
+ *
+ *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+#include <assert.h>
+#include <debug.h>
+
+#include <nuttx/init.h>
+#include <arch/board/board.h>
+
+#include "up_arch.h"
+#include "up_internal.h"
+
+#ifdef CONFIG_ARCH_FPU
+#  include "nvic.h"
+#endif
+
+#include "lpc43_clockconfig.h"
+#include "lpc43_lowputc.h"
+
+/****************************************************************************
+ * Name: showprogress
+ *
+ * Description:
+ *   Print a character on the UART to show boot status.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_DEBUG
+#  define showprogress(c) up_lowputc(c)
+#else
+#  define showprogress(c)
+#endif
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lpc43_fpuconfig
+ *
+ * Description:
+ *   Configure the FPU.  Relative bit settings:
+ *
+ *     CPACR:  Enables access to CP10 and CP11
+ *     CONTROL.FPCA: Determines whether the FP extension is active in the
+ *       current context:
+ *     FPCCR.ASPEN:  Enables automatic FP state preservation, then the
+ *       processor sets this bit to 1 on successful completion of any FP
+ *       instruction.
+ *     FPCCR.LSPEN:  Enables lazy context save of FP state. When this is
+ *       done, the processor reserves space on the stack for the FP state,
+ *       but does not save that state information to the stack.
+ *
+ *  Software must not change the value of the ASPEN bit or LSPEN bit while either:
+ *   - the CPACR permits access to CP10 and CP11, that give access to the FP
+ *     extension, or
+ *   - the CONTROL.FPCA bit is set to 1
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_ARCH_FPU
+#ifdef CONFIG_ARMV7M_CMNVECTOR
+
+static inline void lpc43_fpuconfig(void)
+{
+  uint32_t regval;
+
+  /* Set CONTROL.FPCA so that we always get the extended context frame
+   * with the volatile FP registers stacked above the basic context.
+   */
+
+  regval = getcontrol(); 
+  regval |= (1 << 2);
+  setcontrol(regval);
+
+  /* Ensure that FPCCR.LSPEN is disabled, so that we don't have to contend
+   * with the lazy FP context save behaviour.  Clear FPCCR.ASPEN since we
+   * are going to turn on CONTROL.FPCA for all contexts.
+   */
+
+  regval = getreg32(NVIC_FPCCR);
+  regval &= ~((1 << 31) | (1 << 30));
+  putreg32(regval, NVIC_FPCCR);
+
+  /* Enable full access to CP10 and CP11 */
+
+  regval = getreg32(NVIC_CPACR);
+  regval |= ((3 << (2*10)) | (3 << (2*11)));
+  putreg32(regval, NVIC_CPACR);
+}
+
+#else
+
+static inline void lpc43_fpuconfig(void)
+{
+  uint32_t regval;
+
+  /* Clear CONTROL.FPCA so that we do not get the extended context frame
+   * with the volatile FP registers stacked in the saved context.
+   */
+
+  regval = getcontrol(); 
+  regval &= ~(1 << 2);
+  setcontrol(regval);
+
+  /* Ensure that FPCCR.LSPEN is disabled, so that we don't have to contend
+   * with the lazy FP context save behaviour.  Clear FPCCR.ASPEN since we
+   * are going to keep CONTROL.FPCA off for all contexts.
+   */
+
+  regval = getreg32(NVIC_FPCCR);
+  regval &= ~((1 << 31) | (1 << 30));
+  putreg32(regval, NVIC_FPCCR);
+
+  /* Enable full access to CP10 and CP11 */
+
+  regval = getreg32(NVIC_CPACR);
+  regval |= ((3 << (2*10)) | (3 << (2*11)));
+  putreg32(regval, NVIC_CPACR);
+}
+
+#endif
+
+#else
+#  define lpc43_fpuconfig()
+#endif
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: _start
+ *
+ * Description:
+ *   This is the reset entry point.
+ *
+ ****************************************************************************/
+
+void __start(void)
+{
+  const uint32_t *src;
+  uint32_t *dest;
+
+  /* Configure the uart so that we can get debug output as soon as possible */
+
+  lpc43_clockconfig();
+  lpc43_fpuconfig();
+  lpc43_lowsetup();
+  showprogress('A');
+
+  /* Clear .bss.  We'll do this inline (vs. calling memset) just to be
+   * certain that there are no issues with the state of global variables.
+   */
+
+  for (dest = &_sbss; dest < &_ebss; )
+    {
+      *dest++ = 0;
+    }
+  showprogress('B');
+
+  /* Move the intialized data section from his temporary holding spot in
+   * FLASH into the correct place in SRAM.  The correct place in SRAM is
+   * give by _sdata and _edata.  The temporary location is in FLASH at the
+   * end of all of the other read-only data (.text, .rodata) at _eronly.
+   */
+
+  for (src = &_eronly, dest = &_sdata; dest < &_edata; )
+    {
+      *dest++ = *src++;
+    }
+  showprogress('C');
+
+  /* Perform early serial initialization */
+
+#ifdef USE_EARLYSERIALINIT
+  up_earlyserialinit();
+#endif
+  showprogress('D');
+
+  /* Initialize onboard resources */
+
+  lpc43_boardinitialize();
+  showprogress('E');
+
+  /* Then start NuttX */
+
+  showprogress('\r');
+  showprogress('\n');
+  os_start();
+
+  /* Shoulnd't get here */
+
+  for(;;);
+}