问FreeRTOS -硬件故障分析-故障

EN

extern "C" __attribute__((naked)) void HardFault_Handler()
{
  __disable_fault_irq();
  __disable_irq();
  prepareRegistersFromStack();
}

extern "C" void prepareRegistersFromStack()
{
  __asm volatile
  (
      " tst lr, #4                                                \n"
      " ite eq                                                    \n"
      " mrseq r0, msp                                             \n"
      " mrsne r0, psp                                             \n"
      " ldr r1, [r0, #24]                                         \n"
      " ldr r2, handler2_address_const                            \n"
      " bx r2                                                     \n"
      " handler2_address_const: .word getRegistersFromStack       \n"
  );
}

extern "C" void getRegistersFromStack( uint32_t *pulFaultStackAddress )
{
  uint32_t dummy;
  /* These are volatile to try and prevent the compiler/linker optimising them
     away as the variables never actually get used.  If the debugger won't show the
     values of the variables, make them global my moving their declaration outside
     of this function. */
  volatile uint32_t r0;
  volatile uint32_t r1;
  volatile uint32_t r2;
  volatile uint32_t r3;
  volatile uint32_t r12;
  volatile uint32_t lr; /* Link register. */
  volatile uint32_t pc; /* Program counter. */
  volatile uint32_t psr;/* Program status register. */

  r0 = pulFaultStackAddress[ 0 ];
  r1 = pulFaultStackAddress[ 1 ];
  r2 = pulFaultStackAddress[ 2 ];
  r3 = pulFaultStackAddress[ 3 ];

  r12 = pulFaultStackAddress[ 4 ];
  lr  = pulFaultStackAddress[ 5 ];
  pc  = pulFaultStackAddress[ 6 ];
  psr = pulFaultStackAddress[ 7 ];

  /* When the following line is hit, the variables contain the register values. */
  for(;;);

  /* remove warnings */
  dummy = r0;
  dummy = r1;
  dummy = r2;
  dummy = r3;
  dummy = r12;
  dummy = lr;
  dummy = pc;
  dummy = psr;
  dummy = dummy;
}