ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c

   1 /** @file
   2   Default exception handler
   3
   4   Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
   5   Copyright (c) 2012, ARM Ltd. All rights reserved.<BR>
   6
   7   This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <Uefi.h>
  18 #include <Library/BaseLib.h>
  19 #include <Library/DebugLib.h>
  20 #include <Library/PeCoffGetEntryPointLib.h>
  21 #include <Library/PrintLib.h>
  22 #include <Library/ArmDisassemblerLib.h>
  23 #include <Library/SerialPortLib.h>
  24
  25 #include <Guid/DebugImageInfoTable.h>
  26
  27 #include <Protocol/DebugSupport.h>
  28 #include <Library/DefaultExceptionHandlerLib.h>
  29
  30 typedef struct {
  31   UINT32  BIT;
  32   CHAR8   Char;
  33 } CPSR_CHAR;
  34
  35 CHAR8 *
  36 GetImageName (
  37   IN  UINTN  FaultAddress,
  38   OUT UINTN  *ImageBase,
  39   OUT UINTN  *PeCoffSizeOfHeaders
  40   );
  41
  42 /**
  43   Convert the Current Program Status Register (CPSR) to a string. The string is
  44   a defacto standard in the ARM world.
  45
  46   It is possible to add extra bits by adding them to CpsrChar array.
  47
  48   @param  Cpsr         ARM CPSR register value
  49   @param  ReturnStr    32 byte string that contains string version of CPSR
  50
  51 **/
  52 VOID
  53 CpsrString (
  54   IN  UINT32  Cpsr,
  55   OUT CHAR8   *ReturnStr
  56   )
  57 {
  58   UINTN     Index;
  59   CHAR8*    Str;
  60   CHAR8*    ModeStr;
  61   CPSR_CHAR CpsrChar[] = {
  62     { 31, 'n' },
  63     { 30, 'z' },
  64     { 29, 'c' },
  65     { 28, 'v' },
  66
  67     { 9,  'e' },
  68     { 8,  'a' },
  69     { 7,  'i' },
  70     { 6,  'f' },
  71     { 5,  't' },
  72     { 0,  '?' }
  73   };
  74
  75   Str = ReturnStr;
  76
  77   for (Index = 0; CpsrChar[Index].BIT != 0; Index++, Str++) {
  78     *Str = CpsrChar[Index].Char;
  79     if ((Cpsr & (1 << CpsrChar[Index].BIT)) != 0) {
  80       // Concert to upper case if bit is set
  81       *Str &= ~0x20;
  82     }
  83   }
  84
  85   *Str++ = '_';
  86   *Str = '\0';
  87
  88   switch (Cpsr & 0x1f) {
  89   case 0x10:
  90     ModeStr = "usr";
  91     break;
  92   case 0x011:
  93     ModeStr = "fiq";
  94     break;
  95   case 0x12:
  96     ModeStr = "irq";
  97     break;
  98   case 0x13:
  99     ModeStr = "svc";
 100     break;
 101   case 0x16:
 102     ModeStr = "mon";
 103     break;
 104   case 0x17:
 105     ModeStr = "abt";
 106     break;
 107   case 0x1b:
 108     ModeStr = "und";
 109     break;
 110   case 0x1f:
 111     ModeStr = "sys";
 112     break;
 113
 114   default:
 115     ModeStr = "???";
 116     break;
 117   }
 118
 119   AsciiStrCat (Str, ModeStr);
 120   return;
 121 }
 122
 123 CHAR8 *
 124 FaultStatusToString (
 125   IN  UINT32  Status
 126   )
 127 {
 128   CHAR8 *FaultSource;
 129
 130   switch (Status) {
 131     case 0x01: FaultSource = "Alignment fault"; break;
 132     case 0x02: FaultSource = "Debug event fault"; break;
 133     case 0x03: FaultSource = "Access Flag fault on Section"; break;
 134     case 0x04: FaultSource = "Cache maintenance operation fault[2]"; break;
 135     case 0x05: FaultSource = "Translation fault on Section"; break;
 136     case 0x06: FaultSource = "Access Flag fault on Page"; break;
 137     case 0x07: FaultSource = "Translation fault on Page"; break;
 138     case 0x08: FaultSource = "Precise External Abort"; break;
 139     case 0x09: FaultSource = "Domain fault on Section"; break;
 140     case 0x0b: FaultSource = "Domain fault on Page"; break;
 141     case 0x0c: FaultSource = "External abort on translation, first level"; break;
 142     case 0x0d: FaultSource = "Permission fault on Section"; break;
 143     case 0x0e: FaultSource = "External abort on translation, second level"; break;
 144     case 0x0f: FaultSource = "Permission fault on Page"; break;
 145     case 0x16: FaultSource = "Imprecise External Abort"; break;
 146     default:   FaultSource = "No function"; break;
 147     }
 148
 149   return FaultSource;
 150 }
 151
 152 STATIC CHAR8 *gExceptionTypeString[] = {
 153   "Reset",
 154   "Undefined OpCode",
 155   "SVC",
 156   "Prefetch Abort",
 157   "Data Abort",
 158   "Undefined",
 159   "IRQ",
 160   "FIQ"
 161 };
 162
 163 /**
 164   This is the default action to take on an unexpected exception
 165
 166   Since this is exception context don't do anything crazy like try to allcoate memory.
 167
 168   @param  ExceptionType    Type of the exception
 169   @param  SystemContext    Register state at the time of the Exception
 170
 171
 172 **/
 173 VOID
 174 DefaultExceptionHandler (
 175   IN     EFI_EXCEPTION_TYPE           ExceptionType,
 176   IN OUT EFI_SYSTEM_CONTEXT           SystemContext
 177   )
 178 {
 179   CHAR8     Buffer[100];
 180   UINTN     CharCount;
 181   UINT32    DfsrStatus;
 182   UINT32    IfsrStatus;
 183   BOOLEAN   DfsrWrite;
 184   UINT32    PcAdjust = 0;
 185
 186   CharCount = AsciiSPrint (Buffer,sizeof (Buffer),"\n%a Exception PC at 0x%08x  CPSR 0x%08x ",
 187          gExceptionTypeString[ExceptionType], SystemContext.SystemContextArm->PC, SystemContext.SystemContextArm->CPSR);
 188   SerialPortWrite ((UINT8 *) Buffer, CharCount);
 189
 190   DEBUG_CODE_BEGIN ();
 191     CHAR8   *Pdb;
 192     UINT32  ImageBase;
 193     UINT32  PeCoffSizeOfHeader;
 194     UINT32  Offset;
 195     CHAR8   CpsrStr[32];  // char per bit. Lower 5-bits are mode that is a 3 char string
 196     CHAR8   Buffer[80];
 197     UINT8   *DisAsm;
 198     UINT32  ItBlock;
 199
 200     CpsrString (SystemContext.SystemContextArm->CPSR, CpsrStr);
 201     DEBUG ((EFI_D_ERROR, "%a\n", CpsrStr));
 202
 203     Pdb = GetImageName (SystemContext.SystemContextArm->PC, &ImageBase, &PeCoffSizeOfHeader);
 204     Offset = SystemContext.SystemContextArm->PC - ImageBase;
 205     if (Pdb != NULL) {
 206       DEBUG ((EFI_D_ERROR, "%a\n", Pdb));
 207
 208       //
 209       // A PE/COFF image loads its headers into memory so the headers are
 210       // included in the linked addresses. ELF and Mach-O images do not
 211       // include the headers so the first byte of the image is usually
 212       // text (code). If you look at link maps from ELF or Mach-O images
 213       // you need to subtract out the size of the PE/COFF header to get
 214       // get the offset that matches the link map.
 215       //
 216       DEBUG ((EFI_D_ERROR, "loaded at 0x%08x (PE/COFF offset) 0x%x (ELF or Mach-O offset) 0x%x", ImageBase, Offset, Offset - PeCoffSizeOfHeader));
 217
 218       // If we come from an image it is safe to show the instruction. We know it should not fault
 219       DisAsm = (UINT8 *)(UINTN)SystemContext.SystemContextArm->PC;
 220       ItBlock = 0;
 221       DisassembleInstruction (&DisAsm, (SystemContext.SystemContextArm->CPSR & BIT5) == BIT5, TRUE, &ItBlock, Buffer, sizeof (Buffer));
 222       DEBUG ((EFI_D_ERROR, "\n%a", Buffer));
 223
 224       switch (ExceptionType) {
 225       case EXCEPT_ARM_UNDEFINED_INSTRUCTION:
 226       case EXCEPT_ARM_SOFTWARE_INTERRUPT:
 227       case EXCEPT_ARM_PREFETCH_ABORT:
 228       case EXCEPT_ARM_DATA_ABORT:
 229         // advance PC past the faulting instruction
 230         PcAdjust = (UINTN)DisAsm - SystemContext.SystemContextArm->PC;
 231         break;
 232
 233       default:
 234         break;
 235       }
 236
 237     }
 238   DEBUG_CODE_END ();
 239   DEBUG ((EFI_D_ERROR, "\n  R0 0x%08x   R1 0x%08x   R2 0x%08x   R3 0x%08x\n", SystemContext.SystemContextArm->R0, SystemContext.SystemContextArm->R1, SystemContext.SystemContextArm->R2, SystemContext.SystemContextArm->R3));
 240   DEBUG ((EFI_D_ERROR, "  R4 0x%08x   R5 0x%08x   R6 0x%08x   R7 0x%08x\n", SystemContext.SystemContextArm->R4, SystemContext.SystemContextArm->R5, SystemContext.SystemContextArm->R6, SystemContext.SystemContextArm->R7));
 241   DEBUG ((EFI_D_ERROR, "  R8 0x%08x   R9 0x%08x  R10 0x%08x  R11 0x%08x\n", SystemContext.SystemContextArm->R8, SystemContext.SystemContextArm->R9, SystemContext.SystemContextArm->R10, SystemContext.SystemContextArm->R11));
 242   DEBUG ((EFI_D_ERROR, " R12 0x%08x   SP 0x%08x   LR 0x%08x   PC 0x%08x\n", SystemContext.SystemContextArm->R12, SystemContext.SystemContextArm->SP, SystemContext.SystemContextArm->LR, SystemContext.SystemContextArm->PC));
 243   DEBUG ((EFI_D_ERROR, "DFSR 0x%08x DFAR 0x%08x IFSR 0x%08x IFAR 0x%08x\n", SystemContext.SystemContextArm->DFSR, SystemContext.SystemContextArm->DFAR, SystemContext.SystemContextArm->IFSR, SystemContext.SystemContextArm->IFAR));
 244
 245   // Bit10 is Status[4] Bit3:0 is Status[3:0]
 246   DfsrStatus = (SystemContext.SystemContextArm->DFSR & 0xf) | ((SystemContext.SystemContextArm->DFSR >> 6) & 0x10);
 247   DfsrWrite = (SystemContext.SystemContextArm->DFSR & BIT11) != 0;
 248   if (DfsrStatus != 0x00) {
 249     DEBUG ((EFI_D_ERROR, " %a: %a 0x%08x\n", FaultStatusToString (DfsrStatus), DfsrWrite ? "write to" : "read from", SystemContext.SystemContextArm->DFAR));
 250   }
 251
 252   IfsrStatus = (SystemContext.SystemContextArm->IFSR & 0xf) | ((SystemContext.SystemContextArm->IFSR >> 6) & 0x10);
 253   if (IfsrStatus != 0) {
 254     DEBUG ((EFI_D_ERROR, " Instruction %a at 0x%08x\n", FaultStatusToString (SystemContext.SystemContextArm->IFSR & 0xf), SystemContext.SystemContextArm->IFAR));
 255   }
 256
 257   DEBUG ((EFI_D_ERROR, "\n"));
 258   ASSERT (FALSE);
 259
 260   // Clear the error registers that we have already displayed incase some one wants to keep going
 261   SystemContext.SystemContextArm->DFSR = 0;
 262   SystemContext.SystemContextArm->IFSR = 0;
 263
 264   // If some one is stepping past the exception handler adjust the PC to point to the next instruction
 265   SystemContext.SystemContextArm->PC += PcAdjust;
 266 }