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|
TITLE CpuAsm.asm:
;------------------------------------------------------------------------------
;*
;* Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
;* 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.
;*
;* CpuAsm.asm
;*
;* Abstract:
;*
;------------------------------------------------------------------------------
.686
.model flat,C
.code
EXTRN mErrorCodeFlag:DWORD ; Error code flags for exceptions
;
; point to the external interrupt vector table
;
ExternalVectorTablePtr DWORD 0
InitializeExternalVectorTablePtr PROC PUBLIC
mov eax, [esp+4]
mov ExternalVectorTablePtr, eax
ret
InitializeExternalVectorTablePtr ENDP
;------------------------------------------------------------------------------
; VOID
; SetCodeSelector (
; UINT16 Selector
; );
;------------------------------------------------------------------------------
SetCodeSelector PROC PUBLIC
mov ecx, [esp+4]
sub esp, 0x10
lea eax, setCodeSelectorLongJump
mov [esp], eax
mov [esp+4], cx
jmp fword ptr [esp]
setCodeSelectorLongJump:
add esp, 0x10
ret
SetCodeSelector ENDP
;------------------------------------------------------------------------------
; VOID
; SetDataSelectors (
; UINT16 Selector
; );
;------------------------------------------------------------------------------
SetDataSelectors PROC PUBLIC
mov ecx, [esp+4]
mov ss, cx
mov ds, cx
mov es, cx
mov fs, cx
mov gs, cx
ret
SetDataSelectors ENDP
;---------------------------------------;
; CommonInterruptEntry ;
;---------------------------------------;
; The follow algorithm is used for the common interrupt routine.
CommonInterruptEntry PROC PUBLIC
cli
;
; All interrupt handlers are invoked through interrupt gates, so
; IF flag automatically cleared at the entry point
;
;
; Calculate vector number
;
; Get the return address of call, actually, it is the
; address of vector number.
;
xchg ecx, [esp]
mov cx, [ecx]
and ecx, 0FFFFh
cmp ecx, 32 ; Intel reserved vector for exceptions?
jae NoErrorCode
bt mErrorCodeFlag, ecx
jc HasErrorCode
NoErrorCode:
;
; Stack:
; +---------------------+
; + EFlags +
; +---------------------+
; + CS +
; +---------------------+
; + EIP +
; +---------------------+
; + ECX +
; +---------------------+ <-- ESP
;
; Registers:
; ECX - Vector Number
;
;
; Put Vector Number on stack
;
push ecx
;
; Put 0 (dummy) error code on stack, and restore ECX
;
xor ecx, ecx ; ECX = 0
xchg ecx, [esp+4]
jmp ErrorCodeAndVectorOnStack
HasErrorCode:
;
; Stack:
; +---------------------+
; + EFlags +
; +---------------------+
; + CS +
; +---------------------+
; + EIP +
; +---------------------+
; + Error Code +
; +---------------------+
; + ECX +
; +---------------------+ <-- ESP
;
; Registers:
; ECX - Vector Number
;
;
; Put Vector Number on stack and restore ECX
;
xchg ecx, [esp]
;
; Fall through to join main routine code
; at ErrorCodeAndVectorOnStack
;
@@:
jmp @B
ErrorCodeAndVectorOnStack:
push ebp
mov ebp, esp
;
; Stack:
; +---------------------+
; + EFlags +
; +---------------------+
; + CS +
; +---------------------+
; + EIP +
; +---------------------+
; + Error Code +
; +---------------------+
; + Vector Number +
; +---------------------+
; + EBP +
; +---------------------+ <-- EBP
;
;
; Align stack to make sure that EFI_FX_SAVE_STATE_IA32 of EFI_SYSTEM_CONTEXT_IA32
; is 16-byte aligned
;
and esp, 0fffffff0h
sub esp, 12
;; UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;
push eax
push ecx
push edx
push ebx
lea ecx, [ebp + 6 * 4]
push ecx ; ESP
push dword ptr [ebp] ; EBP
push esi
push edi
;; UINT32 Gs, Fs, Es, Ds, Cs, Ss;
mov eax, ss
push eax
movzx eax, word ptr [ebp + 4 * 4]
push eax
mov eax, ds
push eax
mov eax, es
push eax
mov eax, fs
push eax
mov eax, gs
push eax
;; UINT32 Eip;
mov eax, [ebp + 3 * 4]
push eax
;; UINT32 Gdtr[2], Idtr[2];
sub esp, 8
sidt [esp]
mov eax, [esp + 2]
xchg eax, [esp]
and eax, 0FFFFh
mov [esp+4], eax
sub esp, 8
sgdt [esp]
mov eax, [esp + 2]
xchg eax, [esp]
and eax, 0FFFFh
mov [esp+4], eax
;; UINT32 Ldtr, Tr;
xor eax, eax
str ax
push eax
sldt ax
push eax
;; UINT32 EFlags;
mov eax, [ebp + 5 * 4]
push eax
;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
mov eax, cr4
or eax, 208h
mov cr4, eax
push eax
mov eax, cr3
push eax
mov eax, cr2
push eax
xor eax, eax
push eax
mov eax, cr0
push eax
;; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
mov eax, dr7
push eax
mov eax, dr6
push eax
mov eax, dr3
push eax
mov eax, dr2
push eax
mov eax, dr1
push eax
mov eax, dr0
push eax
;; FX_SAVE_STATE_IA32 FxSaveState;
sub esp, 512
mov edi, esp
db 0fh, 0aeh, 07h ;fxsave [edi]
;; UINT32 ExceptionData;
push dword ptr [ebp + 2 * 4]
;; call into exception handler
mov eax, ExternalVectorTablePtr ; get the interrupt vectors base
or eax, eax ; NULL?
jz nullExternalExceptionHandler
mov ecx, [ebp + 4]
mov eax, [eax + ecx * 4]
or eax, eax ; NULL?
jz nullExternalExceptionHandler
;; Prepare parameter and call
mov edx, esp
push edx
mov edx, dword ptr [ebp + 1 * 4]
push edx
;
; Call External Exception Handler
;
call eax
add esp, 8
nullExternalExceptionHandler:
cli
;; UINT32 ExceptionData;
add esp, 4
;; FX_SAVE_STATE_IA32 FxSaveState;
mov esi, esp
db 0fh, 0aeh, 0eh ; fxrstor [esi]
add esp, 512
;; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
;; Skip restoration of DRx registers to support in-circuit emualators
;; or debuggers set breakpoint in interrupt/exception context
add esp, 4 * 6
;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
pop eax
mov cr0, eax
add esp, 4 ; not for Cr1
pop eax
mov cr2, eax
pop eax
mov cr3, eax
pop eax
mov cr4, eax
;; UINT32 EFlags;
pop dword ptr [ebp + 5 * 4]
;; UINT32 Ldtr, Tr;
;; UINT32 Gdtr[2], Idtr[2];
;; Best not let anyone mess with these particular registers...
add esp, 24
;; UINT32 Eip;
pop dword ptr [ebp + 3 * 4]
;; UINT32 Gs, Fs, Es, Ds, Cs, Ss;
;; NOTE - modified segment registers could hang the debugger... We
;; could attempt to insulate ourselves against this possibility,
;; but that poses risks as well.
;;
pop gs
pop fs
pop es
pop ds
pop dword ptr [ebp + 4 * 4]
pop ss
;; UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;
pop edi
pop esi
add esp, 4 ; not for ebp
add esp, 4 ; not for esp
pop ebx
pop edx
pop ecx
pop eax
mov esp, ebp
pop ebp
add esp, 8
iretd
CommonInterruptEntry ENDP
END
|
