mirror of https://github.com/acidanthera/audk.git
159 lines
5.8 KiB
ArmAsm
Executable File
159 lines
5.8 KiB
ArmAsm
Executable File
#------------------------------------------------------------------------------
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#
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# Copyright (c) 2008-2009 Apple Inc. All rights reserved.
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#
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# All rights reserved. This program and the accompanying materials
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# are licensed and made available under the terms and conditions of the BSD License
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# which accompanies this distribution. The full text of the license may be found at
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# http://opensource.org/licenses/bsd-license.php
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#
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# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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#
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#------------------------------------------------------------------------------
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.text
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.align 2
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.globl _ExceptionHandlersStart
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.globl _ExceptionHandlersEnd
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.globl _CommonExceptionEntry
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.globl _AsmCommonExceptionEntry
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.globl _gExceptionHandlers
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_ExceptionHandlersStart:
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_Reset:
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b _ResetEntry
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_UndefinedInstruction:
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b _UndefinedInstructionEntry
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_SoftwareInterrupt:
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b _SoftwareInterruptEntry
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_PrefetchAbort:
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b _PrefetchAbortEntry
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_DataAbort:
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b _DataAbortEntry
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_ReservedException:
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b _ReservedExceptionEntry
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_Irq:
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b _IrqEntry
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_Fiq:
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b _FiqEntry
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_ResetEntry:
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stmfd sp!,{r0-r1}
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mov r0,#0
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ldr r1,_CommonExceptionEntry
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bx r1
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_UndefinedInstructionEntry:
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stmfd sp!,{r0-r1}
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mov r0,#1
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ldr r1,_CommonExceptionEntry
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bx r1
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_SoftwareInterruptEntry:
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stmfd sp!,{r0-r1}
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mov r0,#2
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ldr r1,_CommonExceptionEntry
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bx r1
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_PrefetchAbortEntry:
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stmfd sp!,{r0-r1}
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mov r0,#3
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sub lr,lr,#4
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ldr r1,_CommonExceptionEntry
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bx r1
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_DataAbortEntry:
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stmfd sp!,{r0-r1}
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mov r0,#4
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sub lr,lr,#8
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ldr r1,_CommonExceptionEntry
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bx r1
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_ReservedExceptionEntry:
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stmfd sp!,{r0-r1}
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mov r0,#5
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ldr r1,_CommonExceptionEntry
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bx r1
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_IrqEntry:
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stmfd sp!,{r0-r1}
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mov r0,#6
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sub lr,lr,#4
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ldr r1,_CommonExceptionEntry
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bx r1
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_FiqEntry:
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stmfd sp!,{r0-r1}
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mov r0,#7
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sub lr,lr,#4
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ldr r1,_CommonExceptionEntry
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bx r1
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_CommonExceptionEntry:
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.byte 0x12
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.byte 0x34
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.byte 0x56
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.byte 0x78
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_ExceptionHandlersEnd:
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LIndirectgExceptionHandlers:
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.long _gExceptionHandlers
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_AsmCommonExceptionEntry:
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mrc p15, 0, r1, c6, c0, 2 @ Read IFAR
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stmfd sp!,{r1} @ Store the IFAR
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mrc p15, 0, r1, c5, c0, 1 @ Read IFSR
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stmfd sp!,{r1} @ Store the IFSR
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mrc p15, 0, r1, c6, c0, 0 @ Read DFAR
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stmfd sp!,{r1} @ Store the DFAR
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mrc p15, 0, r1, c5, c0, 0 @ Read DFSR
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stmfd sp!,{r1} @ Store the DFSR
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mrs r1,spsr @ Read SPSR (which is the pre-exception CPSR)
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stmfd sp!,{r1} @ Store the SPSR
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stmfd sp!,{lr} @ Store the link register (which is the pre-exception PC)
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stmfd sp,{sp,lr}^ @ Store user/system mode stack pointer and link register
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nop @ Required by ARM architecture
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sub sp,sp,#0x08 @ Adjust stack pointer
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stmfd sp!,{r2-r12} @ Store general purpose registers
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ldr r3,[sp,#0x40] @ Read saved R1 from the stack (it was saved by the exception entry routine)
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ldr r2,[sp,#0x3C] @ Read saved R0 from the stack (it was saved by the exception entry routine)
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stmfd sp!,{r2-r3} @ Store general purpose registers R0 and R1
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mov r1,sp @ Prepare System Context pointer as an argument for the exception handler
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ldr r2,LIndirectgExceptionHandlers @ Offset to 32-bit address of exception handler
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ldr r2,[r2] @ Load exception handler table
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ldr r3,[r2,r0,lsl #2] @ Index to find the handler for this exception
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// blx r3 @ Call exception handler
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bx r3 @ Call exception handler
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ldr r2,[sp,#0x40] @ Load CPSR from context, in case it has changed
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msr SPSR_cxsf,r2 @ Store it back to the SPSR to be restored when exiting this handler
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ldmfd sp!,{r0-r12} @ Restore general purpose registers
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ldmia sp,{sp,lr}^ @ Restore user/system mode stack pointer and link register
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nop @ Required by ARM architecture
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add sp,sp,#0x08 @ Adjust stack pointer
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ldmfd sp!,{lr} @ Restore the link register (which is the pre-exception PC)
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add sp,sp,#0x1C @ Clear out the remaining stack space
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movs pc,lr @ Return from exception
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