nuttx/arch/avr/src/avr32/up_nommuhead.S
patacongo c85fcaecdb Rename g_heapbase to g_idle_topstack; Fix kernel build heap allocation which cannot use g_heapbase
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5739 42af7a65-404d-4744-a932-0658087f49c3
2013-03-14 14:42:52 +00:00

158 lines
5.1 KiB
ArmAsm

/****************************************************************************
* arch/avr32/src/avr32/up_nommuhead.S
*
* Copyright (C) 2010 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <arch/avr32/avr32.h>
#include "up_internal.h"
#include "up_arch.h"
/****************************************************************************
* External Symbols
****************************************************************************/
.file "up_nommuhead.S"
.global _sbss /* Start of .bss. Defined by ld.script */
.global _ebss /* End of .bss. Defined by ld.script */
#ifdef CONFIG_BOOT_RUNFROMFLASH
.global _sdata /* Start of .data section in RAM */
.global _edata /* End of .data section in RAM */
.global _eronly /* Start of .data section in FLASH */
#endif
.global up_lowinit /* Perform low level initialization */
.global os_start /* NuttX entry point */
.global vectortab /* Vector base address */
/****************************************************************************
* Macros
****************************************************************************/
/****************************************************************************
* OS Entry Point
****************************************************************************/
/* The following entry point must be linked to execute at 0x80000000 if it
* is to execute upon reset.
*/
.text
.global __start
.type __start, @function
__start:
/* Set the IDLE thread stack pointer. This stack will be used
* through NuttX initialization and will, eventually, be inherited
* by the IDLE thread when threading is enabled.
*/
lddpc sp, .Lstackbase
/* Set up the vector base address so interrupts can be enabled. */
lda.w r0, vectortab
mtsr AVR32_EVBA, r0
/* Enable exception processing */
csrf AVR32_SR_EM_SHIFT
/* Clear system BSS section */
lda.w r0, _sbss /* R =Start of .bss */
lda.w r1, _ebss /* r1=End of .bss */
mov r2, 0 /* Value to write to .bss */
rjmp 2f /* Start at the bottom of the loop */
1:
st.d r0++, r2 /* Zero .bss */
2:
cp r0, r1 /* Finished? */
brlo 1b /* No... keep looping */
/* Copy system .data sections to new home in RAM. */
#ifdef CONFIG_BOOT_RUNFROMFLASH
lda.w r0, _sdata /* r0=Start of .data section in RAM */
lda.w r1, _edata /* r1=End of .data section in RAM */
lda.w r2, _eronly /* r2=Start of .data in FLASH */
rjmp 4f /* Start at the bottom of the loop */
3:
ld.d r4, r2++ /* Fetch the next data value */
st.d r0++, r4 /* Write it to the .data section */
4:
cp r0, r1 /* Finished? */
brlo 3b /* No... keep looping */
#endif
/* Clear the frame pointer and link register since this is the outermost
* frame.
*/
mov r7, 0
mov lr, 0
/* Perform low-level initialization */
mcall .Lup_lowinit
/* Then jump to OS entry (will not return) */
lda.w pc, os_start
.Lstackbase:
.word _ebss+CONFIG_IDLETHREAD_STACKSIZE-4
.Lup_lowinit:
.word up_lowinit
.size __start, .-__start
/* This global variable is unsigned long g_idle_topstack and is
* exported from here only because of its coupling to other
* uses of _ebss in this file
*/
.data
.align 4
.globl g_idle_topstack
.type g_idle_topstack, object
g_idle_topstack:
.long _ebss+CONFIG_IDLETHREAD_STACKSIZE
.size g_idle_topstack, .-g_idle_topstack
.end