1 /* 2 * Copyright (c) 2006-2018, RT-Thread Development Team 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 * 6 * Change Logs: 7 * Date Author Notes 8 * 2011-09-23 Bernard the first version 9 * 2011-10-05 Bernard add thumb mode 10 */ 11 #include <rtthread.h> 12 #include "am33xx.h" 13 14 /** 15 * @addtogroup AM33xx 16 */ 17 /*@{*/ 18 19 /** 20 * This function will initialize thread stack 21 * 22 * @param tentry the entry of thread 23 * @param parameter the parameter of entry 24 * @param stack_addr the beginning stack address 25 * @param texit the function will be called when thread exit 26 * 27 * @return stack address 28 */ rt_hw_stack_init(void * tentry,void * parameter,rt_uint8_t * stack_addr,void * texit)29rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter, 30 rt_uint8_t *stack_addr, void *texit) 31 { 32 rt_uint32_t *stk; 33 34 stack_addr += sizeof(rt_uint32_t); 35 stack_addr = (rt_uint8_t *)RT_ALIGN_DOWN((rt_uint32_t)stack_addr, 8); 36 stk = (rt_uint32_t *)stack_addr; 37 38 *(--stk) = (rt_uint32_t)tentry; /* entry point */ 39 *(--stk) = (rt_uint32_t)texit; /* lr */ 40 *(--stk) = 0xdeadbeef; /* r12 */ 41 *(--stk) = 0xdeadbeef; /* r11 */ 42 *(--stk) = 0xdeadbeef; /* r10 */ 43 *(--stk) = 0xdeadbeef; /* r9 */ 44 *(--stk) = 0xdeadbeef; /* r8 */ 45 *(--stk) = 0xdeadbeef; /* r7 */ 46 *(--stk) = 0xdeadbeef; /* r6 */ 47 *(--stk) = 0xdeadbeef; /* r5 */ 48 *(--stk) = 0xdeadbeef; /* r4 */ 49 *(--stk) = 0xdeadbeef; /* r3 */ 50 *(--stk) = 0xdeadbeef; /* r2 */ 51 *(--stk) = 0xdeadbeef; /* r1 */ 52 *(--stk) = (rt_uint32_t)parameter; /* r0 : argument */ 53 54 /* cpsr */ 55 if ((rt_uint32_t)tentry & 0x01) 56 *(--stk) = SVCMODE | 0x20; /* thumb mode */ 57 else 58 *(--stk) = SVCMODE; /* arm mode */ 59 60 /* return task's current stack address */ 61 return (rt_uint8_t *)stk; 62 } 63 64 /*@}*/ 65