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//------------------------------------------------------------------------------
//
// 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.
//
//------------------------------------------------------------------------------
EXPORT ExceptionHandlersStart
EXPORT ExceptionHandlersEnd
EXPORT CommonExceptionEntry
EXPORT AsmCommonExceptionEntry
IMPORT gExceptionHandlers
AREA DxeExceptionHandlers, CODE, READONLY
ExceptionHandlersStart
Reset
B ResetEntry
UndefinedInstruction
B UndefinedInstructionEntry
SoftwareInterrupt
B SoftwareInterruptEntry
PrefetchAbort
B PrefetchAbortEntry
DataAbort
B DataAbortEntry
ReservedException
B ReservedExceptionEntry
Irq
B IrqEntry
Fiq
B FiqEntry
ResetEntry
STMFD SP!,{R0-R1}
MOV R0,#0
LDR R1,CommonExceptionEntry
BX R1
UndefinedInstructionEntry
STMFD SP!,{R0-R1}
MOV R0,#1
LDR R1,CommonExceptionEntry
BX R1
SoftwareInterruptEntry
STMFD SP!,{R0-R1}
MOV R0,#2
LDR R1,CommonExceptionEntry
BX R1
PrefetchAbortEntry
STMFD SP!,{R0-R1}
MOV R0,#3
SUB LR,LR,#4
LDR R1,CommonExceptionEntry
BX R1
DataAbortEntry
STMFD SP!,{R0-R1}
MOV R0,#4
SUB LR,LR,#8
LDR R1,CommonExceptionEntry
BX R1
ReservedExceptionEntry
STMFD SP!,{R0-R1}
MOV R0,#5
LDR R1,CommonExceptionEntry
BX R1
IrqEntry
STMFD SP!,{R0-R1}
MOV R0,#6
SUB LR,LR,#4
LDR R1,CommonExceptionEntry
BX R1
FiqEntry
STMFD SP!,{R0-R1}
MOV R0,#7
SUB LR,LR,#4
LDR R1,CommonExceptionEntry
BX R1
CommonExceptionEntry
DCD 0x12345678
ExceptionHandlersEnd
AsmCommonExceptionEntry
MRC p15, 0, r1, c6, c0, 2 ; Read IFAR
STMFD SP!,{R1} ; Store the IFAR
MRC p15, 0, r1, c5, c0, 1 ; Read IFSR
STMFD SP!,{R1} ; Store the IFSR
MRC p15, 0, r1, c6, c0, 0 ; Read DFAR
STMFD SP!,{R1} ; Store the DFAR
MRC p15, 0, r1, c5, c0, 0 ; Read DFSR
STMFD SP!,{R1} ; Store the DFSR
MRS R1,SPSR ; Read SPSR (which is the pre-exception CPSR)
STMFD SP!,{R1} ; Store the SPSR
STMFD SP!,{LR} ; Store the link register (which is the pre-exception PC)
STMFD SP,{SP,LR}^ ; Store user/system mode stack pointer and link register
NOP ; Required by ARM architecture
SUB SP,SP,#0x08 ; Adjust stack pointer
STMFD SP!,{R2-R12} ; Store general purpose registers
LDR R3,[SP,#0x40] ; Read saved R1 from the stack (it was saved by the exception entry routine)
LDR R2,[SP,#0x3C] ; Read saved R0 from the stack (it was saved by the exception entry routine)
STMFD SP!,{R2-R3} ; Store general purpose registers R0 and R1
MOV R1,SP ; Prepare System Context pointer as an argument for the exception handler
LDR R2,=gExceptionHandlers ; Load exception handler table
LDR R3,[R2,R0,LSL #2] ; Index to find the handler for this exception
BLX R3 ; Call exception handler
LDR R2,[SP,#0x40] ; Load CPSR from context, in case it has changed
MSR SPSR_cxsf,R2 ; Store it back to the SPSR to be restored when exiting this handler
LDMFD SP!,{R0-R12} ; Restore general purpose registers
LDM SP,{SP,LR}^ ; Restore user/system mode stack pointer and link register
NOP ; Required by ARM architecture
ADD SP,SP,#0x08 ; Adjust stack pointer
LDMFD SP!,{LR} ; Restore the link register (which is the pre-exception PC)
ADD SP,SP,#0x1C ; Clear out the remaining stack space
MOVS PC,LR ; Return from exception
END
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