ArmPkg/Drivers/CpuDxe/Exception.c

   1 /** @file
   2
   3   Copyright (c) 2008-2009, Apple Inc. All rights reserved.
   4
   5   All rights reserved. This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "CpuDxe.h"
  16 #include <Library/CacheMaintenanceLib.h>
  17
  18 VOID
  19 ExceptionHandlersStart (
  20   VOID
  21   );
  22
  23 VOID
  24 ExceptionHandlersEnd (
  25   VOID
  26   );
  27
  28 VOID
  29 CommonExceptionEntry (
  30   VOID
  31   );
  32
  33 VOID
  34 AsmCommonExceptionEntry (
  35   VOID
  36   );
  37
  38
  39 EFI_EXCEPTION_CALLBACK  gExceptionHandlers[MAX_ARM_EXCEPTION + 1];
  40 EFI_EXCEPTION_CALLBACK  gDebuggerExceptionHandlers[MAX_ARM_EXCEPTION + 1];
  41
  42
  43
  44 /**
  45   This function registers and enables the handler specified by InterruptHandler for a processor
  46   interrupt or exception type specified by InterruptType. If InterruptHandler is NULL, then the
  47   handler for the processor interrupt or exception type specified by InterruptType is uninstalled.
  48   The installed handler is called once for each processor interrupt or exception.
  49
  50   @param  InterruptType    A pointer to the processor's current interrupt state. Set to TRUE if interrupts
  51                            are enabled and FALSE if interrupts are disabled.
  52   @param  InterruptHandler A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called
  53                            when a processor interrupt occurs. If this parameter is NULL, then the handler
  54                            will be uninstalled.
  55
  56   @retval EFI_SUCCESS           The handler for the processor interrupt was successfully installed or uninstalled.
  57   @retval EFI_ALREADY_STARTED   InterruptHandler is not NULL, and a handler for InterruptType was
  58                                 previously installed.
  59   @retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler for InterruptType was not
  60                                 previously installed.
  61   @retval EFI_UNSUPPORTED       The interrupt specified by InterruptType is not supported.
  62
  63 **/
  64 EFI_STATUS
  65 RegisterInterruptHandler (
  66   IN EFI_EXCEPTION_TYPE             InterruptType,
  67   IN EFI_CPU_INTERRUPT_HANDLER      InterruptHandler
  68   )
  69 {
  70   if (InterruptType > MAX_ARM_EXCEPTION) {
  71     return EFI_UNSUPPORTED;
  72   }
  73
  74   if ((InterruptHandler != NULL) && (gExceptionHandlers[InterruptType] != NULL)) {
  75     return EFI_ALREADY_STARTED;
  76   }
  77
  78   gExceptionHandlers[InterruptType] = InterruptHandler;
  79
  80   return EFI_SUCCESS;
  81 }
  82
  83
  84 /**
  85   This function registers and enables the handler specified by InterruptHandler for a processor
  86   interrupt or exception type specified by InterruptType. If InterruptHandler is NULL, then the
  87   handler for the processor interrupt or exception type specified by InterruptType is uninstalled.
  88   The installed handler is called once for each processor interrupt or exception.
  89
  90   @param  InterruptType    A pointer to the processor's current interrupt state. Set to TRUE if interrupts
  91                            are enabled and FALSE if interrupts are disabled.
  92   @param  InterruptHandler A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called
  93                            when a processor interrupt occurs. If this parameter is NULL, then the handler
  94                            will be uninstalled.
  95
  96   @retval EFI_SUCCESS           The handler for the processor interrupt was successfully installed or uninstalled.
  97   @retval EFI_ALREADY_STARTED   InterruptHandler is not NULL, and a handler for InterruptType was
  98                                 previously installed.
  99   @retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler for InterruptType was not
 100                                 previously installed.
 101   @retval EFI_UNSUPPORTED       The interrupt specified by InterruptType is not supported.
 102
 103 **/
 104 EFI_STATUS
 105 RegisterDebuggerInterruptHandler (
 106   IN EFI_EXCEPTION_TYPE             InterruptType,
 107   IN EFI_CPU_INTERRUPT_HANDLER      InterruptHandler
 108   )
 109 {
 110   if (InterruptType > MAX_ARM_EXCEPTION) {
 111     return EFI_UNSUPPORTED;
 112   }
 113
 114   if ((InterruptHandler != NULL) && (gDebuggerExceptionHandlers[InterruptType] != NULL)) {
 115     return EFI_ALREADY_STARTED;
 116   }
 117
 118   gDebuggerExceptionHandlers[InterruptType] = InterruptHandler;
 119
 120   return EFI_SUCCESS;
 121 }
 122
 123 CHAR8 *gExceptionTypeString[] = {
 124   "Reset",
 125   "Undefined Instruction",
 126   "SWI",
 127   "Prefetch Abort",
 128   "Data Abort",
 129   "Undefined",
 130   "IRQ",
 131   "FIQ"
 132 };
 133
 134 VOID
 135 EFIAPI
 136 CommonCExceptionHandler (
 137   IN     EFI_EXCEPTION_TYPE           ExceptionType,
 138   IN OUT EFI_SYSTEM_CONTEXT           SystemContext
 139   )
 140 {
 141   BOOLEAN Dispatched = FALSE;
 142
 143
 144   if (ExceptionType <= MAX_ARM_EXCEPTION) {
 145     if (gDebuggerExceptionHandlers[ExceptionType]) {
 146       //
 147       // If DebugSupport hooked the interrupt call the handler. This does not disable
 148       // the normal handler.
 149       //
 150       gDebuggerExceptionHandlers[ExceptionType] (ExceptionType, SystemContext);
 151       Dispatched = TRUE;
 152     }
 153     if (gExceptionHandlers[ExceptionType]) {
 154       gExceptionHandlers[ExceptionType] (ExceptionType, SystemContext);
 155       Dispatched = TRUE;
 156     }
 157   } else {
 158     DEBUG ((EFI_D_ERROR, "Unknown exception type %d from %08x\n", ExceptionType, SystemContext.SystemContextArm->PC));
 159     ASSERT (FALSE);
 160   }
 161
 162   if (Dispatched) {
 163     //
 164     // We did work so this was an expected ExceptionType
 165     //
 166     return;
 167   }
 168
 169   if (ExceptionType == EXCEPT_ARM_SOFTWARE_INTERRUPT) {
 170     //
 171     // ARM JTAG debuggers some times use this vector, so it is not an error to get one
 172     //
 173     return;
 174   }
 175
 176   //
 177   // Code after here is the default exception handler...
 178   //
 179   DEBUG ((EFI_D_ERROR, "%a Exception from %08x\n", gExceptionTypeString[ExceptionType], SystemContext.SystemContextArm->PC));
 180   ASSERT (FALSE);
 181
 182 }
 183
 184
 185
 186 EFI_STATUS
 187 InitializeExceptions (
 188   IN EFI_CPU_ARCH_PROTOCOL    *Cpu
 189   )
 190 {
 191   EFI_STATUS           Status;
 192   UINTN                Offset;
 193   UINTN                Length;
 194   UINTN                Index;
 195   BOOLEAN              Enabled;
 196   EFI_PHYSICAL_ADDRESS Base;
 197
 198   //
 199   // Disable interrupts
 200   //
 201   Cpu->GetInterruptState (Cpu, &Enabled);
 202   Cpu->DisableInterrupt (Cpu);
 203
 204   //
 205   // Initialize the C entry points for interrupts
 206   //
 207   for (Index = 0; Index <= MAX_ARM_EXCEPTION; Index++) {
 208     Status = RegisterInterruptHandler (Index, NULL);
 209     ASSERT_EFI_ERROR (Status);
 210
 211     Status = RegisterDebuggerInterruptHandler (Index, NULL);
 212     ASSERT_EFI_ERROR (Status);
 213   }
 214
 215   //
 216   // Copy an implementation of the ARM exception vectors to PcdCpuVectorBaseAddress.
 217   //
 218   Length = (UINTN)ExceptionHandlersEnd - (UINTN)ExceptionHandlersStart;
 219
 220   //
 221   // Reserve space for the exception handlers
 222   //
 223   Base = (EFI_PHYSICAL_ADDRESS)PcdGet32 (PcdCpuVectorBaseAddress);
 224   Status = gBS->AllocatePages (AllocateAddress, EfiBootServicesCode, EFI_SIZE_TO_PAGES (Length), &Base);
 225   // If the request was for memory that's not in the memory map (which is often the case for 0x00000000
 226   // on embedded systems, for example, we don't want to hang up.  So we'll check here for a status of
 227   // EFI_NOT_FOUND, and continue in that case.
 228   if (EFI_ERROR(Status) && (Status != EFI_NOT_FOUND)) {
 229     ASSERT_EFI_ERROR (Status);
 230   }
 231
 232   CopyMem ((VOID *)(UINTN)PcdGet32 (PcdCpuVectorBaseAddress), (VOID *)ExceptionHandlersStart, Length);
 233
 234   //
 235   // Patch in the common Assembly exception handler
 236   //
 237   Offset = (UINTN)CommonExceptionEntry - (UINTN)ExceptionHandlersStart;
 238   *(UINTN *) ((UINT8 *)(UINTN)PcdGet32 (PcdCpuVectorBaseAddress) + Offset) = (UINTN)AsmCommonExceptionEntry;
 239
 240   // Flush Caches since we updated executable stuff
 241   InvalidateInstructionCacheRange ((VOID *)PcdGet32(PcdCpuVectorBaseAddress), Length);
 242
 243   if (Enabled) {
 244     //
 245     // Restore interrupt state
 246     //
 247     Status = Cpu->EnableInterrupt (Cpu);
 248   }
 249
 250   return Status;
 251 }