rt-thread/libcpu/arm/cortex-r4/stack.c

88 lines
2.6 KiB
C

/*
* File : stack.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006, RT-Thread Development Team
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://openlab.rt-thread.com/license/LICENSE
*
* Change Logs:
* Date Author Notes
* 2008-12-11 XuXinming first version
* 2013-05-24 Grissiom port to RM48x50
*/
#include <rtthread.h>
#include "armv7.h"
/**
* @addtogroup RM48x50
*/
/*@{*/
/**
* This function will initialize thread stack
*
* @param tentry the entry of thread
* @param parameter the parameter of entry
* @param stack_addr the beginning stack address
* @param texit the function will be called when thread exit
*
* @return stack address
*/
rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter,
rt_uint8_t *stack_addr, void *texit)
{
rt_uint32_t *stk;
stack_addr += sizeof(rt_uint32_t);
stack_addr = (rt_uint8_t *)RT_ALIGN_DOWN((rt_uint32_t)stack_addr, 8);
stk = (rt_uint32_t *)stack_addr;
*(--stk) = (rt_uint32_t)tentry; /* entry point */
*(--stk) = (rt_uint32_t)texit; /* lr */
*(--stk) = 0xdeadbeef; /* r12 */
*(--stk) = 0xdeadbeef; /* r11 */
*(--stk) = 0xdeadbeef; /* r10 */
*(--stk) = 0xdeadbeef; /* r9 */
*(--stk) = 0xdeadbeef; /* r8 */
*(--stk) = 0xdeadbeef; /* r7 */
*(--stk) = 0xdeadbeef; /* r6 */
*(--stk) = 0xdeadbeef; /* r5 */
*(--stk) = 0xdeadbeef; /* r4 */
*(--stk) = 0xdeadbeef; /* r3 */
*(--stk) = 0xdeadbeef; /* r2 */
*(--stk) = 0xdeadbeef; /* r1 */
*(--stk) = (rt_uint32_t)parameter; /* r0 : argument */
/* cpsr */
if ((rt_uint32_t)tentry & 0x01)
*(--stk) = SVCMODE | 0x20; /* thumb mode */
else
*(--stk) = SVCMODE; /* arm mode */
#if defined(__TI_VFP_SUPPORT__) || (defined (__VFP_FP__) && !defined(__SOFTFP__))
#ifndef RT_VFP_LAZY_STACKING
{
int i;
for (i = 0; i < VFP_DATA_NR; i++)
{
*(--stk) = 0;
}
/* FPSCR TODO: do we need to set the values other than 0? */
*(--stk) = 0;
/* FPEXC. Enable the FVP if no lazy stacking. */
*(--stk) = 0x40000000;
}
#else
/* FPEXC. Disable the FVP by default. */
*(--stk) = 0x00000000;
#endif
#endif
/* return task's current stack address */
return (rt_uint8_t *)stk;
}
/*@}*/