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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.
#
#------------------------------------------------------------------------------
.text
.align 3
.globl ASM_PFX(ExceptionHandlersStart)
.globl ASM_PFX(ExceptionHandlersEnd)
.globl ASM_PFX(CommonExceptionEntry)
.globl ASM_PFX(AsmCommonExceptionEntry)
.globl ASM_PFX(CommonCExceptionHandler)
ASM_PFX(ExceptionHandlersStart):
ASM_PFX(Reset):
b ASM_PFX(ResetEntry)
ASM_PFX(UndefinedInstruction):
b ASM_PFX(UndefinedInstructionEntry)
ASM_PFX(SoftwareInterrupt):
b ASM_PFX(SoftwareInterruptEntry)
ASM_PFX(PrefetchAbort):
b ASM_PFX(PrefetchAbortEntry)
ASM_PFX(DataAbort):
b ASM_PFX(DataAbortEntry)
ASM_PFX(ReservedException):
b ASM_PFX(ReservedExceptionEntry)
ASM_PFX(Irq):
b ASM_PFX(IrqEntry)
ASM_PFX(Fiq):
b ASM_PFX(FiqEntry)
ASM_PFX(ResetEntry):
stmfd sp!,{r0-r1}
mov r0,#0
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(UndefinedInstructionEntry):
stmfd sp!,{r0-r1}
mov r0,#1
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(SoftwareInterruptEntry):
stmfd sp!,{r0-r1}
mov r0,#2
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(PrefetchAbortEntry):
stmfd sp!,{r0-r1}
mov r0,#3
sub lr,lr,#4
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(DataAbortEntry):
stmfd sp!,{r0-r1}
mov r0,#4
sub lr,lr,#8
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(ReservedExceptionEntry):
stmfd sp!,{r0-r1}
mov r0,#5
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(IrqEntry):
stmfd sp!,{r0-r1}
mov r0,#6
sub lr,lr,#4
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(FiqEntry):
stmfd sp!,{r0-r1}
mov r0,#7
sub lr,lr,#4
ldr r1,ASM_PFX(CommonExceptionEntry)
bx r1
ASM_PFX(CommonExceptionEntry):
.byte 0x12
.byte 0x34
.byte 0x56
.byte 0x78
ASM_PFX(ExceptionHandlersEnd):
ASM_PFX(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,#0x50] @ Read saved R1 from the stack (it was saved by the exception entry routine)
ldr r2,[sp,#0x4C] @ 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
sub sp,sp,#4 @ Adjust SP to preserve 8-byte alignment
bl ASM_PFX(CommonCExceptionHandler) @ Call exception handler
add sp,sp,#4 @ Adjust SP back to where we were
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
ldmia 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
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