diff options
Diffstat (limited to 'ArmPkg/Drivers/CpuDxe/ArmV6/Exception.c')
| -rw-r--r-- | ArmPkg/Drivers/CpuDxe/ArmV6/Exception.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/ArmPkg/Drivers/CpuDxe/ArmV6/Exception.c b/ArmPkg/Drivers/CpuDxe/ArmV6/Exception.c new file mode 100644 index 00000000..55a71321 --- /dev/null +++ b/ArmPkg/Drivers/CpuDxe/ArmV6/Exception.c @@ -0,0 +1,230 @@ +/** @file
+
+ Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
+
+ This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "CpuDxe.h"
+
+//FIXME: Will not compile on non-ARMv7 builds
+#include <Chipset/ArmV7.h>
+
+VOID
+ExceptionHandlersStart (
+ VOID
+ );
+
+VOID
+ExceptionHandlersEnd (
+ VOID
+ );
+
+VOID
+CommonExceptionEntry (
+ VOID
+ );
+
+VOID
+AsmCommonExceptionEntry (
+ VOID
+ );
+
+
+EFI_EXCEPTION_CALLBACK gExceptionHandlers[MAX_ARM_EXCEPTION + 1];
+EFI_EXCEPTION_CALLBACK gDebuggerExceptionHandlers[MAX_ARM_EXCEPTION + 1];
+
+
+
+/**
+ This function registers and enables the handler specified by InterruptHandler for a processor
+ interrupt or exception type specified by InterruptType. If InterruptHandler is NULL, then the
+ handler for the processor interrupt or exception type specified by InterruptType is uninstalled.
+ The installed handler is called once for each processor interrupt or exception.
+
+ @param InterruptType A pointer to the processor's current interrupt state. Set to TRUE if interrupts
+ are enabled and FALSE if interrupts are disabled.
+ @param InterruptHandler A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called
+ when a processor interrupt occurs. If this parameter is NULL, then the handler
+ will be uninstalled.
+
+ @retval EFI_SUCCESS The handler for the processor interrupt was successfully installed or uninstalled.
+ @retval EFI_ALREADY_STARTED InterruptHandler is not NULL, and a handler for InterruptType was
+ previously installed.
+ @retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler for InterruptType was not
+ previously installed.
+ @retval EFI_UNSUPPORTED The interrupt specified by InterruptType is not supported.
+
+**/
+EFI_STATUS
+RegisterInterruptHandler (
+ IN EFI_EXCEPTION_TYPE InterruptType,
+ IN EFI_CPU_INTERRUPT_HANDLER InterruptHandler
+ )
+{
+ if (InterruptType > MAX_ARM_EXCEPTION) {
+ return EFI_UNSUPPORTED;
+ }
+
+ if ((InterruptHandler != NULL) && (gExceptionHandlers[InterruptType] != NULL)) {
+ return EFI_ALREADY_STARTED;
+ }
+
+ gExceptionHandlers[InterruptType] = InterruptHandler;
+
+ return EFI_SUCCESS;
+}
+
+
+
+
+VOID
+EFIAPI
+CommonCExceptionHandler (
+ IN EFI_EXCEPTION_TYPE ExceptionType,
+ IN OUT EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ if (ExceptionType <= MAX_ARM_EXCEPTION) {
+ if (gExceptionHandlers[ExceptionType]) {
+ gExceptionHandlers[ExceptionType] (ExceptionType, SystemContext);
+ return;
+ }
+ } else {
+ DEBUG ((EFI_D_ERROR, "Unknown exception type %d from %08x\n", ExceptionType, SystemContext.SystemContextArm->PC));
+ ASSERT (FALSE);
+ }
+
+ if (ExceptionType == EXCEPT_ARM_SOFTWARE_INTERRUPT) {
+ //
+ // ARM JTAG debuggers some times use this vector, so it is not an error to get one
+ //
+ return;
+ }
+
+ DefaultExceptionHandler (ExceptionType, SystemContext);
+}
+
+
+
+EFI_STATUS
+InitializeExceptions (
+ IN EFI_CPU_ARCH_PROTOCOL *Cpu
+ )
+{
+ EFI_STATUS Status;
+ UINTN Offset;
+ UINTN Length;
+ UINTN Index;
+ BOOLEAN IrqEnabled;
+ BOOLEAN FiqEnabled;
+ EFI_PHYSICAL_ADDRESS Base;
+ UINT32 *VectorBase;
+
+ Status = EFI_SUCCESS;
+ ZeroMem (gExceptionHandlers,sizeof(*gExceptionHandlers));
+
+ //
+ // Disable interrupts
+ //
+ Cpu->GetInterruptState (Cpu, &IrqEnabled);
+ Cpu->DisableInterrupt (Cpu);
+
+ //
+ // EFI does not use the FIQ, but a debugger might so we must disable
+ // as we take over the exception vectors.
+ //
+ FiqEnabled = ArmGetFiqState ();
+ ArmDisableFiq ();
+
+ if (FeaturePcdGet(PcdRelocateVectorTable) == TRUE) {
+ //
+ // Copy an implementation of the ARM exception vectors to PcdCpuVectorBaseAddress.
+ //
+ Length = (UINTN)ExceptionHandlersEnd - (UINTN)ExceptionHandlersStart;
+
+ // Check if the exception vector is in the low address
+ if (PcdGet32 (PcdCpuVectorBaseAddress) == 0x0) {
+ // Set SCTLR.V to 0 to enable VBAR to be used
+ ArmSetLowVectors ();
+ } else {
+ ArmSetHighVectors ();
+ }
+
+ //
+ // Reserve space for the exception handlers
+ //
+ Base = (EFI_PHYSICAL_ADDRESS)PcdGet32 (PcdCpuVectorBaseAddress);
+ VectorBase = (UINT32 *)(UINTN)Base;
+ Status = gBS->AllocatePages (AllocateAddress, EfiBootServicesCode, EFI_SIZE_TO_PAGES (Length), &Base);
+ // If the request was for memory that's not in the memory map (which is often the case for 0x00000000
+ // on embedded systems, for example, we don't want to hang up. So we'll check here for a status of
+ // EFI_NOT_FOUND, and continue in that case.
+ if (EFI_ERROR(Status) && (Status != EFI_NOT_FOUND)) {
+ ASSERT_EFI_ERROR (Status);
+ }
+
+ if (FeaturePcdGet(PcdDebuggerExceptionSupport) == TRUE) {
+ // Save existing vector table, in case debugger is already hooked in
+ CopyMem ((VOID *)gDebuggerExceptionHandlers, (VOID *)VectorBase, sizeof (gDebuggerExceptionHandlers));
+ }
+
+ // Copy our assembly code into the page that contains the exception vectors.
+ CopyMem ((VOID *)VectorBase, (VOID *)ExceptionHandlersStart, Length);
+
+ //
+ // Patch in the common Assembly exception handler
+ //
+ Offset = (UINTN)CommonExceptionEntry - (UINTN)ExceptionHandlersStart;
+ *(UINTN *) ((UINT8 *)(UINTN)PcdGet32 (PcdCpuVectorBaseAddress) + Offset) = (UINTN)AsmCommonExceptionEntry;
+
+ //
+ // Initialize the C entry points for interrupts
+ //
+ for (Index = 0; Index <= MAX_ARM_EXCEPTION; Index++) {
+ if (!FeaturePcdGet(PcdDebuggerExceptionSupport) ||
+ (gDebuggerExceptionHandlers[Index] == 0) || (gDebuggerExceptionHandlers[Index] == (VOID *)(UINTN)0xEAFFFFFE)) {
+ // Exception handler contains branch to vector location (jmp $) so no handler
+ // NOTE: This code assumes vectors are ARM and not Thumb code
+ Status = RegisterInterruptHandler (Index, NULL);
+ ASSERT_EFI_ERROR (Status);
+ } else {
+ // If the debugger has already hooked put its vector back
+ VectorBase[Index] = (UINT32)(UINTN)gDebuggerExceptionHandlers[Index];
+ }
+ }
+
+ // Flush Caches since we updated executable stuff
+ InvalidateInstructionCacheRange ((VOID *)PcdGet32(PcdCpuVectorBaseAddress), Length);
+
+ //Note: On ARM processor with the Security Extension, the Vector Table can be located anywhere in the memory.
+ // The Vector Base Address Register defines the location
+ ArmWriteVBar (PcdGet32(PcdCpuVectorBaseAddress));
+ } else {
+ // The Vector table must be 32-byte aligned
+ ASSERT(((UINT32)ExceptionHandlersStart & ((1 << 5)-1)) == 0);
+
+ // We do not copy the Exception Table at PcdGet32(PcdCpuVectorBaseAddress). We just set Vector Base Address to point into CpuDxe code.
+ ArmWriteVBar ((UINT32)ExceptionHandlersStart);
+ }
+
+ if (FiqEnabled) {
+ ArmEnableFiq ();
+ }
+
+ if (IrqEnabled) {
+ //
+ // Restore interrupt state
+ //
+ Status = Cpu->EnableInterrupt (Cpu);
+ }
+
+ return Status;
+}
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