diff options
Diffstat (limited to 'EmbeddedPkg/TemplateCpuDxe/Arm/Exceptions.asm')
-rwxr-xr-x | EmbeddedPkg/TemplateCpuDxe/Arm/Exceptions.asm | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/EmbeddedPkg/TemplateCpuDxe/Arm/Exceptions.asm b/EmbeddedPkg/TemplateCpuDxe/Arm/Exceptions.asm new file mode 100755 index 0000000000..b91639d149 --- /dev/null +++ b/EmbeddedPkg/TemplateCpuDxe/Arm/Exceptions.asm @@ -0,0 +1,152 @@ +//------------------------------------------------------------------------------ +// +// 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 + + |