src/main/fc/fc_hardfaults.c

   1 /*
   2  * This file is part of Cleanflight.
   3  *
   4  * Cleanflight is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * Cleanflight is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <stdbool.h>
  19 #include <stdint.h>
  20
  21 #include "platform.h"
  22
  23 #include "drivers/light_led.h"
  24 #include "drivers/time.h"
  25
  26 #include "fc/fc_init.h"
  27
  28 #include "flight/mixer.h"
  29
  30 #ifdef DEBUG_HARDFAULTS
  31
  32 //from: https://mcuoneclipse.com/2012/11/24/debugging-hard-faults-on-arm-cortex-m/
  33 /**
  34  * hard_fault_handler_c:
  35  * This is called from the HardFault_HandlerAsm with a pointer the Fault stack
  36  * as the parameter. We can then read the values from the stack and place them
  37  * into local variables for ease of reading.
  38  * We then read the various Fault Status and Address Registers to help decode
  39  * cause of the fault.
  40  * The function ends with a BKPT instruction to force control back into the debugger
  41  */
  42 void hard_fault_handler_c(unsigned long *hardfault_args)
  43 {
  44   volatile unsigned long stacked_r0 ;
  45   volatile unsigned long stacked_r1 ;
  46   volatile unsigned long stacked_r2 ;
  47   volatile unsigned long stacked_r3 ;
  48   volatile unsigned long stacked_r12 ;
  49   volatile unsigned long stacked_lr ;
  50   volatile unsigned long stacked_pc ;
  51   volatile unsigned long stacked_psr ;
  52   volatile unsigned long _CFSR ;
  53   volatile unsigned long _HFSR ;
  54   volatile unsigned long _DFSR ;
  55   volatile unsigned long _AFSR ;
  56   volatile unsigned long _BFAR ;
  57   volatile unsigned long _MMAR ;
  58
  59   stacked_r0 = ((unsigned long)hardfault_args[0]) ;
  60   stacked_r1 = ((unsigned long)hardfault_args[1]) ;
  61   stacked_r2 = ((unsigned long)hardfault_args[2]) ;
  62   stacked_r3 = ((unsigned long)hardfault_args[3]) ;
  63   stacked_r12 = ((unsigned long)hardfault_args[4]) ;
  64   stacked_lr = ((unsigned long)hardfault_args[5]) ;
  65   stacked_pc = ((unsigned long)hardfault_args[6]) ;
  66   stacked_psr = ((unsigned long)hardfault_args[7]) ;
  67
  68   // Configurable Fault Status Register
  69   // Consists of MMSR, BFSR and UFSR
  70   _CFSR = (*((volatile unsigned long *)(0xE000ED28))) ;
  71
  72   // Hard Fault Status Register
  73   _HFSR = (*((volatile unsigned long *)(0xE000ED2C))) ;
  74
  75   // Debug Fault Status Register
  76   _DFSR = (*((volatile unsigned long *)(0xE000ED30))) ;
  77
  78   // Auxiliary Fault Status Register
  79   _AFSR = (*((volatile unsigned long *)(0xE000ED3C))) ;
  80
  81   // Read the Fault Address Registers. These may not contain valid values.
  82   // Check BFARVALID/MMARVALID to see if they are valid values
  83   // MemManage Fault Address Register
  84   _MMAR = (*((volatile unsigned long *)(0xE000ED34))) ;
  85   // Bus Fault Address Register
  86   _BFAR = (*((volatile unsigned long *)(0xE000ED38))) ;
  87
  88   __asm("BKPT #0\n") ; // Break into the debugger
  89 }
  90
  91 #else
  92
  93 void HardFault_Handler(void)
  94 {
  95     LED2_ON;
  96
  97     // fall out of the sky
  98     const uint8_t requiredStateForMotors = SYSTEM_STATE_CONFIG_LOADED | SYSTEM_STATE_MOTORS_READY;
  99     if ((systemState & requiredStateForMotors) == requiredStateForMotors) {
 100         stopMotors();
 101     }
 102
 103     LED1_OFF;
 104     LED0_OFF;
 105
 106     while (1) {
 107 #ifdef LED2
 108         delay(50);
 109         LED2_TOGGLE;
 110 #endif
 111     }
 112 }
 113
 114 #endif