ArmPkg/Library/ArmExceptionLib/ArmExceptionLib.c

   1 /* @file
   2 *  Main file supporting the SEC Phase for Versatile Express
   3 *
   4 *  Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
   5 *  Copyright (c) 2011-2014, ARM Limited. All rights reserved.
   6 *  Copyright (c) 2016 HP Development Company, L.P.
   7 *
   8 *  This program and the accompanying materials
   9 *  are licensed and made available under the terms and conditions of the BSD License
  10 *  which accompanies this distribution.  The full text of the license may be found at
  11 *  http://opensource.org/licenses/bsd-license.php
  12 *
  13 *  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  14 *  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15 *
  16 **/
  17
  18 #include <Uefi.h>
  19 #include <Library/CpuExceptionHandlerLib.h>
  20
  21 #include <Library/ArmLib.h>
  22 #include <Library/PcdLib.h>
  23 #include <Library/CacheMaintenanceLib.h>
  24 #include <Library/BaseLib.h>
  25 #include <Library/BaseMemoryLib.h>
  26 #include <Library/DebugLib.h>
  27 #include <Library/DefaultExceptionHandlerLib.h>
  28
  29 STATIC
  30 RETURN_STATUS
  31 CopyExceptionHandlers(
  32   IN  PHYSICAL_ADDRESS        BaseAddress
  33   );
  34
  35 EFI_STATUS
  36 EFIAPI
  37 RegisterExceptionHandler(
  38   IN EFI_EXCEPTION_TYPE            ExceptionType,
  39   IN EFI_CPU_INTERRUPT_HANDLER     InterruptHandler
  40   );
  41
  42 VOID
  43 ExceptionHandlersStart(
  44   VOID
  45   );
  46
  47 VOID
  48 ExceptionHandlersEnd(
  49   VOID
  50   );
  51
  52 RETURN_STATUS ArchVectorConfig(
  53   IN  UINTN       VectorBaseAddress
  54   );
  55
  56 // these globals are provided by the architecture specific source (Arm or AArch64)
  57 extern UINTN                    gMaxExceptionNumber;
  58 extern EFI_EXCEPTION_CALLBACK   gExceptionHandlers[];
  59 extern EFI_EXCEPTION_CALLBACK   gDebuggerExceptionHandlers[];
  60 extern PHYSICAL_ADDRESS         gExceptionVectorAlignmentMask;
  61 extern UINTN                    gDebuggerNoHandlerValue;
  62
  63 // A compiler flag adjusts the compilation of this library to a variant where
  64 // the vectors are relocated (copied) to another location versus using the
  65 // vectors in-place.  Since this effects an assembly .align directive we must
  66 // address this at library build time.  Since this affects the build of the
  67 // library we cannot represent this in a PCD since PCDs are evaluated on
  68 // a per-module basis.
  69 #if defined(ARM_RELOCATE_VECTORS)
  70 STATIC CONST BOOLEAN gArmRelocateVectorTable = TRUE;
  71 #else
  72 STATIC CONST BOOLEAN gArmRelocateVectorTable = FALSE;
  73 #endif
  74
  75
  76 /**
  77 Initializes all CPU exceptions entries and provides the default exception handlers.
  78
  79 Caller should try to get an array of interrupt and/or exception vectors that are in use and need to
  80 persist by EFI_VECTOR_HANDOFF_INFO defined in PI 1.3 specification.
  81 If caller cannot get reserved vector list or it does not exists, set VectorInfo to NULL.
  82 If VectorInfo is not NULL, the exception vectors will be initialized per vector attribute accordingly.
  83
  84 @param[in]  VectorInfo    Pointer to reserved vector list.
  85
  86 @retval EFI_SUCCESS           CPU Exception Entries have been successfully initialized
  87 with default exception handlers.
  88 @retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content if VectorInfo is not NULL.
  89 @retval EFI_UNSUPPORTED       This function is not supported.
  90
  91 **/
  92 EFI_STATUS
  93 EFIAPI
  94 InitializeCpuExceptionHandlers(
  95   IN EFI_VECTOR_HANDOFF_INFO       *VectorInfo OPTIONAL
  96   )
  97 {
  98   RETURN_STATUS     Status;
  99   UINTN             VectorBase;
 100
 101   Status = EFI_SUCCESS;
 102
 103   // if we are requested to copy exceptin handlers to another location
 104   if (gArmRelocateVectorTable) {
 105
 106     VectorBase = PcdGet64(PcdCpuVectorBaseAddress);
 107     Status = CopyExceptionHandlers(VectorBase);
 108
 109   }
 110   else { // use VBAR to point to where our exception handlers are
 111
 112     // The vector table must be aligned for the architecture.  If this
 113     // assertion fails ensure the appropriate FFS alignment is in effect,
 114     // which can be accomplished by ensuring the proper Align=X statement
 115     // in the platform packaging rules.  For ARM Align=32 is required and
 116     // for AArch64 Align=4K is required.  Align=Auto can be used but this
 117     // is known to cause an issue with populating the reset vector area
 118     // for encapsulated FVs.
 119     ASSERT(((UINTN)ExceptionHandlersStart & gExceptionVectorAlignmentMask) == 0);
 120
 121     // We do not copy the Exception Table at PcdGet64(PcdCpuVectorBaseAddress). We just set Vector
 122     // Base Address to point into CpuDxe code.
 123     VectorBase = (UINTN)ExceptionHandlersStart;
 124
 125     Status = RETURN_SUCCESS;
 126   }
 127
 128   if (!RETURN_ERROR(Status)) {
 129     // call the architecture-specific routine to prepare for the new vector
 130     // configuration to take effect
 131     ArchVectorConfig(VectorBase);
 132
 133     ArmWriteVBar(VectorBase);
 134   }
 135
 136   return RETURN_SUCCESS;
 137 }
 138
 139 /**
 140 Copies exception handlers to the speciifed address.
 141
 142 Caller should try to get an array of interrupt and/or exception vectors that are in use and need to
 143 persist by EFI_VECTOR_HANDOFF_INFO defined in PI 1.3 specification.
 144 If caller cannot get reserved vector list or it does not exists, set VectorInfo to NULL.
 145 If VectorInfo is not NULL, the exception vectors will be initialized per vector attribute accordingly.
 146
 147 @param[in]  VectorInfo    Pointer to reserved vector list.
 148
 149 @retval EFI_SUCCESS           CPU Exception Entries have been successfully initialized
 150 with default exception handlers.
 151 @retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content if VectorInfo is not NULL.
 152 @retval EFI_UNSUPPORTED       This function is not supported.
 153
 154 **/
 155 STATIC
 156 RETURN_STATUS
 157 CopyExceptionHandlers(
 158   IN  PHYSICAL_ADDRESS        BaseAddress
 159   )
 160 {
 161   RETURN_STATUS        Status;
 162   UINTN                Length;
 163   UINTN                Index;
 164   UINT32               *VectorBase;
 165
 166   // ensure that the destination value specifies an address meeting the vector alignment requirements
 167   ASSERT ((BaseAddress & gExceptionVectorAlignmentMask) == 0);
 168
 169   //
 170   // Copy an implementation of the exception vectors to PcdCpuVectorBaseAddress.
 171   //
 172   Length = (UINTN)ExceptionHandlersEnd - (UINTN)ExceptionHandlersStart;
 173
 174   VectorBase = (UINT32 *)(UINTN)BaseAddress;
 175
 176   if (FeaturePcdGet(PcdDebuggerExceptionSupport) == TRUE) {
 177     // Save existing vector table, in case debugger is already hooked in
 178     CopyMem((VOID *)gDebuggerExceptionHandlers, (VOID *)VectorBase, sizeof (EFI_EXCEPTION_CALLBACK)* (gMaxExceptionNumber+1));
 179   }
 180
 181   // Copy our assembly code into the page that contains the exception vectors.
 182   CopyMem((VOID *)VectorBase, (VOID *)ExceptionHandlersStart, Length);
 183
 184   //
 185   // Initialize the C entry points for interrupts
 186   //
 187   for (Index = 0; Index <= gMaxExceptionNumber; Index++) {
 188     if (!FeaturePcdGet(PcdDebuggerExceptionSupport) ||
 189       (gDebuggerExceptionHandlers[Index] == 0) || (gDebuggerExceptionHandlers[Index] == (VOID *)gDebuggerNoHandlerValue)) {
 190
 191       Status = RegisterExceptionHandler(Index, NULL);
 192       ASSERT_EFI_ERROR(Status);
 193     }
 194     else {
 195       // If the debugger has already hooked put its vector back
 196       VectorBase[Index] = (UINT32)(UINTN)gDebuggerExceptionHandlers[Index];
 197     }
 198   }
 199
 200   // Flush Caches since we updated executable stuff
 201   InvalidateInstructionCacheRange((VOID *)(UINTN)BaseAddress, Length);
 202
 203   return RETURN_SUCCESS;
 204 }
 205
 206
 207 /**
 208 Initializes all CPU interrupt/exceptions entries and provides the default interrupt/exception handlers.
 209
 210 Caller should try to get an array of interrupt and/or exception vectors that are in use and need to
 211 persist by EFI_VECTOR_HANDOFF_INFO defined in PI 1.3 specification.
 212 If caller cannot get reserved vector list or it does not exists, set VectorInfo to NULL.
 213 If VectorInfo is not NULL, the exception vectors will be initialized per vector attribute accordingly.
 214
 215 @param[in]  VectorInfo    Pointer to reserved vector list.
 216
 217 @retval EFI_SUCCESS           All CPU interrupt/exception entries have been successfully initialized
 218 with default interrupt/exception handlers.
 219 @retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content if VectorInfo is not NULL.
 220 @retval EFI_UNSUPPORTED       This function is not supported.
 221
 222 **/
 223 EFI_STATUS
 224 EFIAPI
 225 InitializeCpuInterruptHandlers(
 226 IN EFI_VECTOR_HANDOFF_INFO       *VectorInfo OPTIONAL
 227 )
 228 {
 229   // not needed, this is what the CPU driver is for
 230   return EFI_UNSUPPORTED;
 231 }
 232
 233 /**
 234 Registers a function to be called from the processor exception handler. (On ARM/AArch64 this only
 235 provides exception handlers, not interrupt handling which is provided through the Hardware Interrupt
 236 Protocol.)
 237
 238 This function registers and enables the handler specified by ExceptionHandler for a processor
 239 interrupt or exception type specified by ExceptionType. If ExceptionHandler is NULL, then the
 240 handler for the processor interrupt or exception type specified by ExceptionType is uninstalled.
 241 The installed handler is called once for each processor interrupt or exception.
 242 NOTE: This function should be invoked after InitializeCpuExceptionHandlers() or
 243 InitializeCpuInterruptHandlers() invoked, otherwise EFI_UNSUPPORTED returned.
 244
 245 @param[in]  ExceptionType     Defines which interrupt or exception to hook.
 246 @param[in]  ExceptionHandler  A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called
 247 when a processor interrupt occurs. If this parameter is NULL, then the handler
 248 will be uninstalled.
 249
 250 @retval EFI_SUCCESS           The handler for the processor interrupt was successfully installed or uninstalled.
 251 @retval EFI_ALREADY_STARTED   ExceptionHandler is not NULL, and a handler for ExceptionType was
 252 previously installed.
 253 @retval EFI_INVALID_PARAMETER ExceptionHandler is NULL, and a handler for ExceptionType was not
 254 previously installed.
 255 @retval EFI_UNSUPPORTED       The interrupt specified by ExceptionType is not supported,
 256 or this function is not supported.
 257 **/
 258 RETURN_STATUS
 259 RegisterCpuInterruptHandler(
 260   IN EFI_EXCEPTION_TYPE             ExceptionType,
 261   IN EFI_CPU_INTERRUPT_HANDLER      ExceptionHandler
 262   ) {
 263   if (ExceptionType > gMaxExceptionNumber) {
 264     return RETURN_UNSUPPORTED;
 265   }
 266
 267   if ((ExceptionHandler != NULL) && (gExceptionHandlers[ExceptionType] != NULL)) {
 268     return RETURN_ALREADY_STARTED;
 269   }
 270
 271   gExceptionHandlers[ExceptionType] = ExceptionHandler;
 272
 273   return RETURN_SUCCESS;
 274 }
 275
 276 /**
 277 Register exception handler.
 278
 279 @param  This                  A pointer to the SMM_CPU_SERVICE_PROTOCOL instance.
 280 @param  ExceptionType         Defines which interrupt or exception to hook. Type EFI_EXCEPTION_TYPE and
 281 the valid values for this parameter are defined in EFI_DEBUG_SUPPORT_PROTOCOL
 282 of the UEFI 2.0 specification.
 283 @param  InterruptHandler      A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER
 284 that is called when a processor interrupt occurs.
 285 If this parameter is NULL, then the handler will be uninstalled.
 286
 287 @retval EFI_SUCCESS           The handler for the processor interrupt was successfully installed or uninstalled.
 288 @retval EFI_ALREADY_STARTED   InterruptHandler is not NULL, and a handler for InterruptType was previously installed.
 289 @retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler for InterruptType was not previously installed.
 290 @retval EFI_UNSUPPORTED       The interrupt specified by InterruptType is not supported.
 291
 292 **/
 293 EFI_STATUS
 294 EFIAPI
 295 RegisterExceptionHandler(
 296   IN EFI_EXCEPTION_TYPE            ExceptionType,
 297   IN EFI_CPU_INTERRUPT_HANDLER     InterruptHandler
 298   )
 299 {
 300   return RegisterCpuInterruptHandler(ExceptionType, InterruptHandler);
 301 }
 302
 303 VOID
 304 EFIAPI
 305 CommonCExceptionHandler(
 306   IN     EFI_EXCEPTION_TYPE           ExceptionType,
 307   IN OUT EFI_SYSTEM_CONTEXT           SystemContext
 308   )
 309 {
 310   if (ExceptionType <= gMaxExceptionNumber) {
 311     if (gExceptionHandlers[ExceptionType]) {
 312       gExceptionHandlers[ExceptionType](ExceptionType, SystemContext);
 313       return;
 314     }
 315   }
 316   else {
 317     DEBUG((EFI_D_ERROR, "Unknown exception type %d\n", ExceptionType));
 318     ASSERT(FALSE);
 319   }
 320
 321   DefaultExceptionHandler(ExceptionType, SystemContext);
 322 }
 323
 324 /**
 325   Initializes all CPU exceptions entries with optional extra initializations.
 326
 327   By default, this method should include all functionalities implemented by
 328   InitializeCpuExceptionHandlers(), plus extra initialization works, if any.
 329   This could be done by calling InitializeCpuExceptionHandlers() directly
 330   in this method besides the extra works.
 331
 332   InitData is optional and its use and content are processor arch dependent.
 333   The typical usage of it is to convey resources which have to be reserved
 334   elsewhere and are necessary for the extra initializations of exception.
 335
 336   @param[in]  VectorInfo    Pointer to reserved vector list.
 337   @param[in]  InitData      Pointer to data optional for extra initializations
 338                             of exception.
 339
 340   @retval EFI_SUCCESS             The exceptions have been successfully
 341                                   initialized.
 342   @retval EFI_INVALID_PARAMETER   VectorInfo or InitData contains invalid
 343                                   content.
 344
 345 **/
 346 EFI_STATUS
 347 EFIAPI
 348 InitializeCpuExceptionHandlersEx (
 349   IN EFI_VECTOR_HANDOFF_INFO            *VectorInfo OPTIONAL,
 350   IN CPU_EXCEPTION_INIT_DATA            *InitData OPTIONAL
 351   )
 352 {
 353   return InitializeCpuExceptionHandlers (VectorInfo);
 354 }
 355