Cortex-M3 在C中上报入栈的寄存器和各fault状态寄存器

因为在标准C语音中是不能获取SP指针的。因而，如果想通过C代码来获取入栈的寄存器值，需要配合一小段汇编代码来获取当前的SP值，然后再把这个SP值以参数形式传送给C代码，最后以指针的形式把栈中的各寄存器值输出，同时也可以输出一些想要的各种状态寄存器值。如下：

Keil环境汇编封皮：

 HardFault_Handler\
                 PROC
                 EXPORT  HardFault_Handler         [WEAK]
                 IMPORT    hard_fault_handler_c
                 TST     LR, #
                 ITE     EQ
                 MRSEQ    R0, MSP
                 MRSNE    R0, PSP
                 B        hard_fault_handler_c
                 ENDP

C服务程序，输入为SP的值：

 void hard_fault_handler_c( unsigned int *reg )
 {
     unsigned int stacked_r0;
     unsigned int stacked_r1;
     unsigned int stacked_r2;
     unsigned int stacked_r3;
     unsigned int stacked_r12;
     unsigned int stacked_lr;
     unsigned int stacked_pc;
     unsigned int stacked_psr;

     stacked_r0 = (unsigned int)reg[];
     stacked_r1 = (unsigned int)reg[];
     stacked_r2 = (unsigned int)reg[];
     stacked_r3 = (unsigned int)reg[];

     stacked_r12 = (unsigned int)reg[];
     stacked_lr = (unsigned int)reg[];
     stacked_pc = (unsigned int)reg[];
     stacked_psr = (unsigned int)reg[];

     while(  )
     {
         printf("--> %s\r\n", __FUNCTION__);
         //printf("EXC_RETURN: %08X\r\n", r1);
         printf("R0: %08X\r\n", stacked_r0);
         printf("R1: %08X\r\n", stacked_r1);
         printf("R2: %08X\r\n", stacked_r2);
         printf("R3: %08X\r\n", stacked_r3);
         printf("R12: %08X\r\n", stacked_r12);
         printf("LR: %08X\r\n", stacked_lr);
         printf("PC: %08X\r\n", stacked_pc);
         printf("PSR: %08X\r\n", stacked_psr);

         // 系统handler控制及状态寄存器
         printf("SHCSR: %08X\r\n", (*(volatile unsigned int *)(0xE000ED24)));
         //printf("MFSR: %02X\r\n", (*(volatile unsigned char *)(0xE000ED28)));
         //printf("BFSR: %02X\r\n", (*(volatile unsigned char *)(0xE000ED29)));
         //printf("UFSR: %04X\r\n", (*(volatile unsigned short *)(0xE000ED2A)));
         // 存储器管理fault、总线fault、用法fault状态寄存器
         printf("CFSR: %08X\r\n", (*(volatile unsigned int *)(0xE000ED28)));
         // 硬fault状态寄存器
         printf("HFSR: %08X\r\n", (*(volatile unsigned int *)(0xE000ED2C)));
         // 调试fault状态寄存器
         printf("DFSR: %08X\r\n", (*(volatile unsigned int *)(0xE000ED30)));

         // 存储器管理fault地址寄存器
         printf("MMAR: %08X\r\n", (*(volatile unsigned int *)(0xE000ED34)));
         // 总线fault地址寄存器
         printf("BFAR: %08X\r\n", (*(volatile unsigned int *)(0xE000ED38)));
         // 辅助fault地址寄存器
         printf("AFAR: %08X\r\n", (*(volatile unsigned int *)(0xE000ED3C)));
     }

     return ;
 }

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参考摘录：

《ARM Cortex-M3权威指南.pdf》