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文章目录
- 问题小结
- 栈未对齐
经过几天的调试,成功将rt-thead 移植到 RA4M2(Cortex-M33 核)上,thread 和 shell 命令已经都成功支持。
问题小结
在完成 rt-thread 代码 Makefile 编译系统搭建后,就开始着手 rt-thread OS 的移植,不幸的是开始就遇到了问题:cortex-m33/context_gcc.S
在退出 PendSV_Handler
的时候发生了 HardFault_Handler
,由于没有打印信息也不知道是什么原因导致 hardfault, 此外由于很久没有调试Cortex-M系列的core了,也不知道去查看哪些寄存器来分析错误原因?
栈未对齐
Memory zones:
Zone: "Default" Description: Default access mode
Cortex-M33 identified.
J-Link>h
PC = 000002EC, CycleCnt = 003535BF
R0 = 20000C50, R1 = 20001A28, R2 = 00000000, R3 = 00000003
R4 = 00000000, R5 = FFFFFFBC, R6 = 00000000, R7 = 00000000
R8 = DEADBEEF, R9 = DEADBEEF, R10= DEADBEEF, R11= DEADBEEF
R12= 00000002
SP(R13)= 20000C28, MSP= 20000C28, PSP= 20001A28, R14(LR) = FFFFFFFD
XPSR = 2900000E: APSR = nzCvQ, EPSR = 01000000, IPSR = 00E (PendSV)
CFBP = 00000000, CONTROL = 00, FAULTMASK = 00, BASEPRI = 00, PRIMASK = 00
MSPLIM = 20000848
PSPLIM = 00000000
Security extension regs:
MSP_S = 20000C28, MSP_NS = 00000000
MSPLIM_S = 20000848, MSPLIM_NS = 00000000
PSP_S = 20001A28, PSP_NS = 1F36C7B0
PSPLIM_S = 00000000, PSPLIM_NS = 00000000
CONTROL_S = 00, FAULTMASK_S = 00, BASEPRI_S = 00, PRIMASK_S = 00
CONTROL_NS = 00, FAULTMASK_NS = 00, BASEPRI_NS = 00, PRIMASK_NS = 00
FPS0 = 00000000, FPS1 = 00000000, FPS2 = 00000000, FPS3 = 00000000
FPS4 = 00000000, FPS5 = 00000000, FPS6 = 00000000, FPS7 = 00000000
FPS8 = 00000000, FPS9 = 00000000, FPS10= 00000000, FPS11= 00000000
FPS12= 00000000, FPS13= 00000000, FPS14= 00000000, FPS15= 00000000
FPS16= 00000000, FPS17= 00000000, FPS18= 00000000, FPS19= 00000000
FPS20= 00000000, FPS21= 00000000, FPS22= 00000000, FPS23= 00000000
FPS24= 00000000, FPS25= 00000000, FPS26= 00000000, FPS27= 00000000
FPS28= 00000000, FPS29= 00000000, FPS30= 00000000, FPS31= 00000000
FPSCR= 00000000
J-Link>mem32 0x20001a18 16
20001A18 = DEADBEEF DEADBEEF DEADBEEF DEADBEEF
20001A28 = DEADBEEF DEADBEEF DEADBEEF DEADBEEF
20001A38 = 00000000 00000000 00000000 00000000
20001A48 = 00000000 00000AAD 0000055D 01000000
20001A58 = C9EC9E68 000005A9 1F58CD19 ABFBE429
20001A68 = 1D0D6F06 117A1FBC
J-Link>mem32 0x20001a08 16
20001A08 = 00000000 FFFFFFBC 00000000 00000000
20001A18 = DEADBEEF DEADBEEF DEADBEEF DEADBEEF
20001A28 = DEADBEEF DEADBEEF DEADBEEF DEADBEEF
20001A38 = 00000000 00000000 00000000 00000000
20001A48 = 00000000 00000AAD 0000055D 01000000
20001A58 = C9EC9E68 000005A9
J-Link>
cortex-m33/cpuport.c
rt_uint8_t *rt_hw_stack_init(void *tentry,
void *parameter,
rt_uint8_t *stack_addr,
void *texit)
{
struct stack_frame *stack_frame;
rt_uint8_t *stk;
unsigned long i;
stk = stack_addr + sizeof(rt_uint32_t);
stk = (rt_uint8_t *)RT_ALIGN_DOWN((rt_uint32_t)stk, 8);
stk -= sizeof(struct stack_frame);
stack_frame = (struct stack_frame *)stk;
/* init all register */
for (i = 0; i < sizeof(struct stack_frame) / sizeof(rt_uint32_t); i ++)
{
((rt_uint32_t *)stack_frame)[i] = 0xdeadbeef;
}
stack_frame->exception_stack_frame.r0 = (unsigned long)parameter; /* r0 : argument */
stack_frame->exception_stack_frame.r1 = 0; /* r1 */
stack_frame->exception_stack_frame.r2 = 0; /* r2 */
stack_frame->exception_stack_frame.r3 = 0; /* r3 */
stack_frame->exception_stack_frame.r12 = 0; /* r12 */
stack_frame->exception_stack_frame.lr = (unsigned long)texit; /* lr */
stack_frame->exception_stack_frame.pc = (unsigned long)tentry; /* entry point, pc */
stack_frame->exception_stack_frame.psr = 0x01000000L; /* PSR */
stack_frame->tz = 0x00;
stack_frame->lr = 0xFFFFFFBC;
stack_frame->psplim = 0x00;
stack_frame->control = 0x00;
/* return task's current stack address */
return stk;
栈结构:
struct exception_stack_frame
{
rt_uint32_t r0;
rt_uint32_t r1;
rt_uint32_t r2;
rt_uint32_t r3;
rt_uint32_t r12;
rt_uint32_t lr;
rt_uint32_t pc;
rt_uint32_t psr;
};
struct stack_frame
{
rt_uint32_t tz;
rt_uint32_t lr;
rt_uint32_t psplim;
rt_uint32_t control;
/* r4 ~ r11 register */
rt_uint32_t r4;
rt_uint32_t r5;
rt_uint32_t r6;
rt_uint32_t r7;
rt_uint32_t r8;
rt_uint32_t r9;
rt_uint32_t r10;
rt_uint32_t r11;
struct exception_stack_frame exception_stack_frame;
};
具体内容待补充…
TODO