xref: /nrf52832-nimble/rt-thread/libcpu/arm/lpc24xx/stack.c (revision 042d53a763ad75cb1465103098bb88c245d95138)
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  * 2008-12-11     XuXinming    first version
9  */
10 #include <rtthread.h>
11 #include "LPC24xx.h"
12 
13 /**
14  * @addtogroup LPC2478
15  */
16 /*@{*/
17 
18 /**
19  * This function will initialize thread stack
20  *
21  * @param tentry the entry of thread
22  * @param parameter the parameter of entry
23  * @param stack_addr the beginning stack address
24  * @param texit the function will be called when thread exit
25  *
26  * @return stack address
27  */
28 rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter,
29                              rt_uint8_t *stack_addr, void *texit)
30 {
31     rt_uint32_t *stk;
32 
33     stack_addr += sizeof(rt_uint32_t);
34     stack_addr  = (rt_uint8_t *)RT_ALIGN_DOWN((rt_uint32_t)stack_addr, 8);
35     stk      = (rt_uint32_t *)stack_addr;
36 
37     *(--stk) = (rt_uint32_t)tentry;         /* entry point */
38     *(--stk) = (rt_uint32_t)texit;          /* lr */
39     *(--stk) = 0xdeadbeef;                  /* r12 */
40     *(--stk) = 0xdeadbeef;                  /* r11 */
41     *(--stk) = 0xdeadbeef;                  /* r10 */
42     *(--stk) = 0xdeadbeef;                  /* r9 */
43     *(--stk) = 0xdeadbeef;                  /* r8 */
44     *(--stk) = 0xdeadbeef;                  /* r7 */
45     *(--stk) = 0xdeadbeef;                  /* r6 */
46     *(--stk) = 0xdeadbeef;                  /* r5 */
47     *(--stk) = 0xdeadbeef;                  /* r4 */
48     *(--stk) = 0xdeadbeef;                  /* r3 */
49     *(--stk) = 0xdeadbeef;                  /* r2 */
50     *(--stk) = 0xdeadbeef;                  /* r1 */
51     *(--stk) = (rt_uint32_t)parameter;      /* r0 : argument */
52 
53     /* cpsr */
54     if ((rt_uint32_t)tentry & 0x01)
55         *(--stk) = SVCMODE | 0x20;          /* thumb mode */
56     else
57         *(--stk) = SVCMODE;                 /* arm mode   */
58 
59     /* return task's current stack address */
60     return (rt_uint8_t *)stk;
61 }
62 
63 /*@}*/
64