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
