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 #include <Library/UefiBootServicesTableLib.h>
  25 #include <Library/UefiLib.h>
  26
  27 #include <Guid/DebugImageInfoTable.h>
  28
  29 #include <Protocol/DebugSupport.h>
  30 #include <Library/DefaultExceptionHandlerLib.h>
  31
  32 //
  33 // The number of elements in a CHAR8 array, including the terminating NUL, that
  34 // is meant to hold the string rendering of the CPSR.
  35 //
  36 #define CPSR_STRING_SIZE 32
  37
  38 typedef struct {
  39   UINT32  BIT;
  40   CHAR8   Char;
  41 } CPSR_CHAR;
  42
  43 CHAR8 *
  44 GetImageName (
  45   IN  UINTN  FaultAddress,
  46   OUT UINTN  *ImageBase,
  47   OUT UINTN  *PeCoffSizeOfHeaders
  48   );
  49
  50 /**
  51   Convert the Current Program Status Register (CPSR) to a string. The string is
  52   a defacto standard in the ARM world.
  53
  54   It is possible to add extra bits by adding them to CpsrChar array.
  55
  56   @param  Cpsr         ARM CPSR register value
  57   @param  ReturnStr    CPSR_STRING_SIZE byte string that contains string
  58                        version of CPSR
  59
  60 **/
  61 VOID
  62 CpsrString (
  63   IN  UINT32  Cpsr,
  64   OUT CHAR8   *ReturnStr
  65   )
  66 {
  67   UINTN     Index;
  68   CHAR8*    Str;
  69   CHAR8*    ModeStr;
  70   CPSR_CHAR CpsrChar[] = {
  71     { 31, 'n' },
  72     { 30, 'z' },
  73     { 29, 'c' },
  74     { 28, 'v' },
  75
  76     { 9,  'e' },
  77     { 8,  'a' },
  78     { 7,  'i' },
  79     { 6,  'f' },
  80     { 5,  't' },
  81     { 0,  '?' }
  82   };
  83
  84   Str = ReturnStr;
  85
  86   for (Index = 0; CpsrChar[Index].BIT != 0; Index++, Str++) {
  87     *Str = CpsrChar[Index].Char;
  88     if ((Cpsr & (1 << CpsrChar[Index].BIT)) != 0) {
  89       // Concert to upper case if bit is set
  90       *Str &= ~0x20;
  91     }
  92   }
  93
  94   *Str++ = '_';
  95   *Str = '\0';
  96
  97   switch (Cpsr & 0x1f) {
  98   case 0x10:
  99     ModeStr = "usr";
 100     break;
 101   case 0x011:
 102     ModeStr = "fiq";
 103     break;
 104   case 0x12:
 105     ModeStr = "irq";
 106     break;
 107   case 0x13:
 108     ModeStr = "svc";
 109     break;
 110   case 0x16:
 111     ModeStr = "mon";
 112     break;
 113   case 0x17:
 114     ModeStr = "abt";
 115     break;
 116   case 0x1b:
 117     ModeStr = "und";
 118     break;
 119   case 0x1f:
 120     ModeStr = "sys";
 121     break;
 122
 123   default:
 124     ModeStr = "???";
 125     break;
 126   }
 127
 128   //
 129   // See the interface contract in the leading comment block.
 130   //
 131   AsciiStrCatS (Str, CPSR_STRING_SIZE - (Str - ReturnStr), ModeStr);
 132 }
 133
 134 CHAR8 *
 135 FaultStatusToString (
 136   IN  UINT32  Status
 137   )
 138 {
 139   CHAR8 *FaultSource;
 140
 141   switch (Status) {
 142     case 0x01: FaultSource = "Alignment fault"; break;
 143     case 0x02: FaultSource = "Debug event fault"; break;
 144     case 0x03: FaultSource = "Access Flag fault on Section"; break;
 145     case 0x04: FaultSource = "Cache maintenance operation fault[2]"; break;
 146     case 0x05: FaultSource = "Translation fault on Section"; break;
 147     case 0x06: FaultSource = "Access Flag fault on Page"; break;
 148     case 0x07: FaultSource = "Translation fault on Page"; break;
 149     case 0x08: FaultSource = "Precise External Abort"; break;
 150     case 0x09: FaultSource = "Domain fault on Section"; break;
 151     case 0x0b: FaultSource = "Domain fault on Page"; break;
 152     case 0x0c: FaultSource = "External abort on translation, first level"; break;
 153     case 0x0d: FaultSource = "Permission fault on Section"; break;
 154     case 0x0e: FaultSource = "External abort on translation, second level"; break;
 155     case 0x0f: FaultSource = "Permission fault on Page"; break;
 156     case 0x16: FaultSource = "Imprecise External Abort"; break;
 157     default:   FaultSource = "No function"; break;
 158     }
 159
 160   return FaultSource;
 161 }
 162
 163 STATIC CHAR8 *gExceptionTypeString[] = {
 164   "Reset",
 165   "Undefined OpCode",
 166   "SVC",
 167   "Prefetch Abort",
 168   "Data Abort",
 169   "Undefined",
 170   "IRQ",
 171   "FIQ"
 172 };
 173
 174 /**
 175   This is the default action to take on an unexpected exception
 176
 177   Since this is exception context don't do anything crazy like try to allcoate memory.
 178
 179   @param  ExceptionType    Type of the exception
 180   @param  SystemContext    Register state at the time of the Exception
 181
 182
 183 **/
 184 VOID
 185 DefaultExceptionHandler (
 186   IN     EFI_EXCEPTION_TYPE           ExceptionType,
 187   IN OUT EFI_SYSTEM_CONTEXT           SystemContext
 188   )
 189 {
 190   CHAR8     Buffer[100];
 191   UINTN     CharCount;
 192   UINT32    DfsrStatus;
 193   UINT32    IfsrStatus;
 194   BOOLEAN   DfsrWrite;
 195   UINT32    PcAdjust = 0;
 196
 197   CharCount = AsciiSPrint (Buffer,sizeof (Buffer),"\n%a Exception PC at 0x%08x  CPSR 0x%08x ",
 198          gExceptionTypeString[ExceptionType], SystemContext.SystemContextArm->PC, SystemContext.SystemContextArm->CPSR);
 199   SerialPortWrite ((UINT8 *)Buffer, CharCount);
 200   if (gST->ConOut != NULL) {
 201     AsciiPrint (Buffer);
 202   }
 203
 204   DEBUG_CODE_BEGIN ();
 205     CHAR8   *Pdb;
 206     UINT32  ImageBase;
 207     UINT32  PeCoffSizeOfHeader;
 208     UINT32  Offset;
 209     CHAR8   CpsrStr[CPSR_STRING_SIZE];  // char per bit. Lower 5-bits are mode
 210                                         // that is a 3 char string
 211     CHAR8   Buffer[80];
 212     UINT8   *DisAsm;
 213     UINT32  ItBlock;
 214
 215     CpsrString (SystemContext.SystemContextArm->CPSR, CpsrStr);
 216     DEBUG ((EFI_D_ERROR, "%a\n", CpsrStr));
 217
 218     Pdb = GetImageName (SystemContext.SystemContextArm->PC, &ImageBase, &PeCoffSizeOfHeader);
 219     Offset = SystemContext.SystemContextArm->PC - ImageBase;
 220     if (Pdb != NULL) {
 221       DEBUG ((EFI_D_ERROR, "%a\n", Pdb));
 222
 223       //
 224       // A PE/COFF image loads its headers into memory so the headers are
 225       // included in the linked addresses. ELF and Mach-O images do not
 226       // include the headers so the first byte of the image is usually
 227       // text (code). If you look at link maps from ELF or Mach-O images
 228       // you need to subtract out the size of the PE/COFF header to get
 229       // get the offset that matches the link map.
 230       //
 231       DEBUG ((EFI_D_ERROR, "loaded at 0x%08x (PE/COFF offset) 0x%x (ELF or Mach-O offset) 0x%x", ImageBase, Offset, Offset - PeCoffSizeOfHeader));
 232
 233       // If we come from an image it is safe to show the instruction. We know it should not fault
 234       DisAsm = (UINT8 *)(UINTN)SystemContext.SystemContextArm->PC;
 235       ItBlock = 0;
 236       DisassembleInstruction (&DisAsm, (SystemContext.SystemContextArm->CPSR & BIT5) == BIT5, TRUE, &ItBlock, Buffer, sizeof (Buffer));
 237       DEBUG ((EFI_D_ERROR, "\n%a", Buffer));
 238
 239       switch (ExceptionType) {
 240       case EXCEPT_ARM_UNDEFINED_INSTRUCTION:
 241       case EXCEPT_ARM_SOFTWARE_INTERRUPT:
 242       case EXCEPT_ARM_PREFETCH_ABORT:
 243       case EXCEPT_ARM_DATA_ABORT:
 244         // advance PC past the faulting instruction
 245         PcAdjust = (UINTN)DisAsm - SystemContext.SystemContextArm->PC;
 246         break;
 247
 248       default:
 249         break;
 250       }
 251
 252     }
 253   DEBUG_CODE_END ();
 254   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));
 255   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));
 256   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));
 257   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));
 258   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));
 259
 260   // Bit10 is Status[4] Bit3:0 is Status[3:0]
 261   DfsrStatus = (SystemContext.SystemContextArm->DFSR & 0xf) | ((SystemContext.SystemContextArm->DFSR >> 6) & 0x10);
 262   DfsrWrite = (SystemContext.SystemContextArm->DFSR & BIT11) != 0;
 263   if (DfsrStatus != 0x00) {
 264     DEBUG ((EFI_D_ERROR, " %a: %a 0x%08x\n", FaultStatusToString (DfsrStatus), DfsrWrite ? "write to" : "read from", SystemContext.SystemContextArm->DFAR));
 265   }
 266
 267   IfsrStatus = (SystemContext.SystemContextArm->IFSR & 0xf) | ((SystemContext.SystemContextArm->IFSR >> 6) & 0x10);
 268   if (IfsrStatus != 0) {
 269     DEBUG ((EFI_D_ERROR, " Instruction %a at 0x%08x\n", FaultStatusToString (SystemContext.SystemContextArm->IFSR & 0xf), SystemContext.SystemContextArm->IFAR));
 270   }
 271
 272   DEBUG ((EFI_D_ERROR, "\n"));
 273   ASSERT (FALSE);
 274
 275   CpuDeadLoop ();   // may return if executing under a debugger
 276
 277   // Clear the error registers that we have already displayed incase some one wants to keep going
 278   SystemContext.SystemContextArm->DFSR = 0;
 279   SystemContext.SystemContextArm->IFSR = 0;
 280
 281   // If some one is stepping past the exception handler adjust the PC to point to the next instruction
 282   SystemContext.SystemContextArm->PC += PcAdjust;
 283 }