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/** @file
Copyright (c) 2008-2009, Apple Inc. All rights reserved.
All rights reserved. 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"
#include <Library/CacheMaintenanceLib.h>
extern BOOLEAN gExceptionContext;
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;
}
/**
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
RegisterDebuggerInterruptHandler (
IN EFI_EXCEPTION_TYPE InterruptType,
IN EFI_CPU_INTERRUPT_HANDLER InterruptHandler
)
{
if (InterruptType > MAX_ARM_EXCEPTION) {
return EFI_UNSUPPORTED;
}
if ((InterruptHandler != NULL) && (gDebuggerExceptionHandlers[InterruptType] != NULL)) {
return EFI_ALREADY_STARTED;
}
gDebuggerExceptionHandlers[InterruptType] = InterruptHandler;
return EFI_SUCCESS;
}
CHAR8 *gExceptionTypeString[] = {
"Reset",
"Undefined Instruction",
"SWI",
"Prefetch Abort",
"Data Abort",
"Undefined",
"IRQ",
"FIQ"
};
VOID
EFIAPI
CommonCExceptionHandler (
IN EFI_EXCEPTION_TYPE ExceptionType,
IN OUT EFI_SYSTEM_CONTEXT SystemContext
)
{
BOOLEAN Dispatched = FALSE;
gExceptionContext = TRUE;
if (ExceptionType <= MAX_ARM_EXCEPTION) {
if (gDebuggerExceptionHandlers[ExceptionType]) {
//
// If DebugSupport hooked the interrupt call the handler. This does not disable
// the normal handler.
//
gDebuggerExceptionHandlers[ExceptionType] (ExceptionType, SystemContext);
Dispatched = TRUE;
}
if (gExceptionHandlers[ExceptionType]) {
gExceptionHandlers[ExceptionType] (ExceptionType, SystemContext);
Dispatched = TRUE;
}
} else {
DEBUG ((EFI_D_ERROR, "Unknown exception type %d from %08x\n", ExceptionType, SystemContext.SystemContextArm->PC));
ASSERT (FALSE);
}
gExceptionContext = FALSE;
if (Dispatched) {
//
// We did work so this was an expected ExceptionType
//
return;
}
if (ExceptionType == EXCEPT_ARM_SOFTWARE_INTERRUPT) {
//
// ARM JTAG debuggers some times use this vector, so it is not an error to get one
//
return;
}
//
// Code after here is the default exception handler...
//
DEBUG ((EFI_D_ERROR, "%a Exception from %08x\n", gExceptionTypeString[ExceptionType], SystemContext.SystemContextArm->PC));
ASSERT (FALSE);
}
EFI_STATUS
InitializeExceptions (
IN EFI_CPU_ARCH_PROTOCOL *Cpu
)
{
EFI_STATUS Status;
UINTN Offset;
UINTN Length;
UINTN Index;
BOOLEAN Enabled;
EFI_PHYSICAL_ADDRESS Base;
//
// Disable interrupts
//
Cpu->GetInterruptState (Cpu, &Enabled);
Cpu->DisableInterrupt (Cpu);
//
// Initialize the C entry points for interrupts
//
for (Index = 0; Index <= MAX_ARM_EXCEPTION; Index++) {
Status = RegisterInterruptHandler (Index, NULL);
ASSERT_EFI_ERROR (Status);
Status = RegisterDebuggerInterruptHandler (Index, NULL);
ASSERT_EFI_ERROR (Status);
}
//
// Copy an implementation of the ARM exception vectors to PcdCpuVectorBaseAddress.
//
Length = (UINTN)ExceptionHandlersEnd - (UINTN)ExceptionHandlersStart;
//
// Reserve space for the exception handlers
//
Base = (EFI_PHYSICAL_ADDRESS)PcdGet32 (PcdCpuVectorBaseAddress);
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);
}
CopyMem ((VOID *)(UINTN)PcdGet32 (PcdCpuVectorBaseAddress), (VOID *)ExceptionHandlersStart, Length);
//
// Patch in the common Assembly exception handler
//
Offset = (UINTN)CommonExceptionEntry - (UINTN)ExceptionHandlersStart;
*(UINTN *) ((UINT8 *)(UINTN)PcdGet32 (PcdCpuVectorBaseAddress) + Offset) = (UINTN)AsmCommonExceptionEntry;
// Flush Caches since we updated executable stuff
InvalidateInstructionCacheRange ((VOID *)PcdGet32(PcdCpuVectorBaseAddress), Length);
if (Enabled) {
//
// Restore interrupt state
//
Status = Cpu->EnableInterrupt (Cpu);
}
return Status;
}
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