Diff: rtos/TARGET_CORTEX/TARGET_CORTEX_M/mbed_rtx_fault_handler.c

Revision:

0:38ceb79fef03

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rtos/TARGET_CORTEX/TARGET_CORTEX_M/mbed_rtx_fault_handler.c	Wed Nov 28 15:10:15 2018 +0000
@@ -0,0 +1,134 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2018 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "rtx_os.h"
+#include "device.h"
+#include "platform/mbed_error.h"
+#include "platform/mbed_interface.h"
+#include "hal/serial_api.h"
+
+#ifndef MBED_FAULT_HANDLER_DISABLED
+#include "mbed_rtx_fault_handler.h"
+
+//Functions Prototypes
+void print_context_info(void);
+
+//Global for populating the context in exception handler
+mbed_fault_context_t mbed_fault_context;
+
+//This is a handler function called from Fault handler to print the error information out.
+//This runs in fault context and uses special functions(defined in mbed_rtx_fault_handler.c) to print the information without using C-lib support.
+void mbed_fault_handler (uint32_t fault_type, void *mbed_fault_context_in, void *osRtxInfoIn)
+{
+    mbed_error_status_t faultStatus = MBED_SUCCESS;
+    
+    mbed_error_printf("\n++ MbedOS Fault Handler ++\n\nFaultType: ");
+        
+    switch( fault_type ) {
+      case MEMMANAGE_FAULT_EXCEPTION: 
+        mbed_error_printf("MemManageFault"); 
+        faultStatus = MBED_ERROR_MEMMANAGE_EXCEPTION;
+        break;
+      
+      case BUS_FAULT_EXCEPTION: 
+        mbed_error_printf("BusFault"); 
+        faultStatus = MBED_ERROR_BUSFAULT_EXCEPTION;
+        break;
+      
+      case USAGE_FAULT_EXCEPTION: 
+        mbed_error_printf("UsageFault"); 
+        faultStatus = MBED_ERROR_USAGEFAULT_EXCEPTION;
+        break;
+      
+      //There is no way we can hit this code without getting an exception, so we have the default treated like hardfault
+      case HARD_FAULT_EXCEPTION: 
+      default:    
+        mbed_error_printf("HardFault");
+        faultStatus = MBED_ERROR_HARDFAULT_EXCEPTION;      
+        break;
+    }
+    mbed_error_printf("\n\nContext:");
+    print_context_info();
+    
+    mbed_error_printf("\n\n-- MbedOS Fault Handler --\n\n");
+    
+    //Now call mbed_error, to log the error and halt the system
+    mbed_error( faultStatus, "Fault exception", mbed_fault_context.PC_reg, NULL, 0 );
+    
+}
+
+MBED_NOINLINE void print_context_info(void)
+{
+    //Context Regs
+    for(int i=0;i<13;i++) {
+        mbed_error_printf("\nR%-4d: %08X", i, ((uint32_t *)&mbed_fault_context)[i]);  
+    }
+        
+    mbed_error_printf("\nSP   : %08X" 
+                      "\nLR   : %08X" 
+                      "\nPC   : %08X" 
+                      "\nxPSR : %08X" 
+                      "\nPSP  : %08X" 
+                      "\nMSP  : %08X", mbed_fault_context.SP_reg, mbed_fault_context.LR_reg, mbed_fault_context.PC_reg, 
+                                     mbed_fault_context.xPSR, mbed_fault_context.PSP, mbed_fault_context.MSP );
+                       
+    //Capture CPUID to get core/cpu info
+    mbed_error_printf("\nCPUID: %08X", SCB->CPUID);
+    
+#if !defined(TARGET_M0) && !defined(TARGET_M0P)
+    //Capture fault information registers to infer the cause of exception
+    mbed_error_printf("\nHFSR : %08X"
+                    "\nMMFSR: %08X"
+                    "\nBFSR : %08X"
+                    "\nUFSR : %08X"
+                    "\nDFSR : %08X"
+                    "\nAFSR : %08X"  ////Split/Capture CFSR into MMFSR, BFSR, UFSR
+                    ,SCB->HFSR, (0xFF & SCB->CFSR), ((0xFF00 & SCB->CFSR) >> 8), ((0xFFFF0000 & SCB->CFSR) >> 16), SCB->DFSR, SCB->AFSR ); 
+    
+    //Print MMFAR only if its valid as indicated by MMFSR
+    if ((0xFF & SCB->CFSR) & 0x80) {
+        mbed_error_printf("\nMMFAR: %08X",SCB->MMFAR); 
+    }
+    //Print BFAR only if its valid as indicated by BFSR
+    if (((0xFF00 & SCB->CFSR) >> 8) & 0x80) {
+        mbed_error_printf("\nBFAR : %08X",SCB->BFAR); 
+    }
+#endif
+    
+    //Print Mode
+    if (mbed_fault_context.EXC_RETURN & 0x8) {
+        mbed_error_printf("\nMode : Thread");
+        //Print Priv level in Thread mode - We capture CONTROL reg which reflects the privilege.
+        //Note that the CONTROL register captured still reflects the privilege status of the 
+        //thread mode eventhough we are in Handler mode by the time we capture it.
+        if(mbed_fault_context.CONTROL & 0x1) {
+            mbed_error_printf("\nPriv : User"); 
+        } else {
+            mbed_error_printf("\nPriv : Privileged"); 
+        }        
+    } else {
+        mbed_error_printf("\nMode : Handler"); 
+        mbed_error_printf("\nPriv : Privileged"); 
+    }
+    //Print Return Stack
+    if (mbed_fault_context.EXC_RETURN & 0x4) {
+        mbed_error_printf("\nStack: PSP"); 
+    } else {
+        mbed_error_printf("\nStack: MSP"); 
+    }
+}
+
+#endif //MBED_FAULT_HANDLER_SUPPORT