[mirror_edk2.git] / UefiCpuPkg / Library / CpuExceptionHandlerLib / Ia32 / ExceptionHandlerAsm.asm

;------------------------------------------------------------------------------ ;\r
; Copyright (c) 2012 - 2013, Intel Corporation. All rights reserved.<BR>\r
; This program and the accompanying materials\r
; are licensed and made available under the terms and conditions of the BSD License\r
; which accompanies this distribution.  The full text of the license may be found at\r
; http://opensource.org/licenses/bsd-license.php.\r
;\r
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
;\r
; Module Name:\r
;\r
;   ExceptionHandlerAsm.Asm\r
;\r
; Abstract:\r
;\r
;   IA32 CPU Exception Handler\r
;\r
; Notes:\r
;\r
;------------------------------------------------------------------------------\r
\r
    .686\r
    .model  flat,C\r
\r
;\r
; CommonExceptionHandler()\r
;\r
CommonExceptionHandler             PROTO   C\r
\r
.data\r
\r
EXTRN mErrorCodeFlag:DWORD            ; Error code flags for exceptions\r
EXTRN mDoFarReturnFlag:DWORD          ; Do far return flag\r
\r
.code\r
\r
ALIGN   8\r
\r
;\r
; exception handler stub table\r
;\r
AsmIdtVectorBegin:\r
REPEAT  32\r
    db      6ah        ; push  #VectorNum\r
    db      ($ - AsmIdtVectorBegin) / ((AsmIdtVectorEnd - AsmIdtVectorBegin) / 32) ; VectorNum\r
    push    eax\r
    mov     eax, CommonInterruptEntry\r
    jmp     eax\r
ENDM\r
AsmIdtVectorEnd:\r
\r
HookAfterStubBegin:\r
    db      6ah        ; push\r
VectorNum:\r
    db      0          ; 0 will be fixed \r
    push    eax\r
    mov     eax, HookAfterStubHeaderEnd\r
    jmp     eax\r
HookAfterStubHeaderEnd:\r
    pop     eax\r
    sub     esp, 8     ; reserve room for filling exception data later\r
    push    [esp + 8]\r
    xchg    ecx, [esp] ; get vector number\r
    bt      mErrorCodeFlag, ecx\r
    jnc     @F\r
    push    [esp]      ; addition push if exception data needed\r
@@:\r
    xchg    ecx, [esp] ; restore ecx\r
    push    eax\r
\r
;----------------------------------------------------------------------------;\r
; CommonInterruptEntry                                                               ;\r
;----------------------------------------------------------------------------;\r
; The follow algorithm is used for the common interrupt routine.\r
; Entry from each interrupt with a push eax and eax=interrupt number\r
; Stack:\r
; +---------------------+\r
; +    EFlags           +\r
; +---------------------+\r
; +    CS               +\r
; +---------------------+\r
; +    EIP              +\r
; +---------------------+\r
; +    Error Code       +\r
; +---------------------+\r
; +    Vector Number    +\r
; +---------------------+\r
; +    EBP              +\r
; +---------------------+ <-- EBP\r
CommonInterruptEntry PROC PUBLIC\r
    cli\r
    pop    eax\r
    ;\r
    ; All interrupt handlers are invoked through interrupt gates, so\r
    ; IF flag automatically cleared at the entry point\r
    ;\r
\r
    ;\r
    ; Get vector number from top of stack\r
    ;\r
    xchg    ecx, [esp]\r
    and     ecx, 0FFh       ; Vector number should be less than 256\r
    cmp     ecx, 32         ; Intel reserved vector for exceptions?\r
    jae     NoErrorCode\r
    bt      mErrorCodeFlag, ecx\r
    jc      HasErrorCode\r
\r
NoErrorCode:\r
\r
    ;\r
    ; Stack:\r
    ; +---------------------+\r
    ; +    EFlags           +\r
    ; +---------------------+\r
    ; +    CS               +\r
    ; +---------------------+\r
    ; +    EIP              +\r
    ; +---------------------+\r
    ; +    ECX              +\r
    ; +---------------------+ <-- ESP\r
    ;\r
    ; Registers:\r
    ;   ECX - Vector Number\r
    ;\r
\r
    ;\r
    ; Put Vector Number on stack\r
    ;\r
    push    ecx\r
\r
    ;\r
    ; Put 0 (dummy) error code on stack, and restore ECX\r
    ;\r
    xor     ecx, ecx  ; ECX = 0\r
    xchg    ecx, [esp+4]\r
\r
    jmp     ErrorCodeAndVectorOnStack\r
\r
HasErrorCode:\r
\r
    ;\r
    ; Stack:\r
    ; +---------------------+\r
    ; +    EFlags           +\r
    ; +---------------------+\r
    ; +    CS               +\r
    ; +---------------------+\r
    ; +    EIP              +\r
    ; +---------------------+\r
    ; +    Error Code       +\r
    ; +---------------------+\r
    ; +    ECX              +\r
    ; +---------------------+ <-- ESP\r
    ;\r
    ; Registers:\r
    ;   ECX - Vector Number\r
    ;\r
\r
    ;\r
    ; Put Vector Number on stack and restore ECX\r
    ;\r
    xchg    ecx, [esp]\r
\r
ErrorCodeAndVectorOnStack:\r
    push    ebp\r
    mov     ebp, esp\r
\r
    ;\r
    ; Stack:\r
    ; +---------------------+\r
    ; +    EFlags           +\r
    ; +---------------------+\r
    ; +    CS               +\r
    ; +---------------------+\r
    ; +    EIP              +\r
    ; +---------------------+\r
    ; +    Error Code       +\r
    ; +---------------------+\r
    ; +    Vector Number    +\r
    ; +---------------------+\r
    ; +    EBP              +\r
    ; +---------------------+ <-- EBP\r
    ;\r
\r
    ;\r
    ; Align stack to make sure that EFI_FX_SAVE_STATE_IA32 of EFI_SYSTEM_CONTEXT_IA32\r
    ; is 16-byte aligned\r
    ;\r
    and     esp, 0fffffff0h\r
    sub     esp, 12\r
\r
    sub     esp, 8\r
    push    0            ; clear EXCEPTION_HANDLER_CONTEXT.OldIdtHandler\r
    push    0            ; clear EXCEPTION_HANDLER_CONTEXT.ExceptionDataFlag\r
       \r
;; UINT32  Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;\r
    push    eax\r
    push    ecx\r
    push    edx\r
    push    ebx\r
    lea     ecx, [ebp + 6 * 4]\r
    push    ecx                          ; ESP\r
    push    dword ptr [ebp]              ; EBP\r
    push    esi\r
    push    edi\r
\r
;; UINT32  Gs, Fs, Es, Ds, Cs, Ss;\r
    mov     eax, ss\r
    push    eax\r
    movzx   eax, word ptr [ebp + 4 * 4]\r
    push    eax\r
    mov     eax, ds\r
    push    eax\r
    mov     eax, es\r
    push    eax\r
    mov     eax, fs\r
    push    eax\r
    mov     eax, gs\r
    push    eax\r
\r
;; UINT32  Eip;\r
    mov     eax, [ebp + 3 * 4]\r
    push    eax\r
\r
;; UINT32  Gdtr[2], Idtr[2];\r
    sub     esp, 8\r
    sidt    [esp]\r
    mov     eax, [esp + 2]\r
    xchg    eax, [esp]\r
    and     eax, 0FFFFh\r
    mov     [esp+4], eax\r
\r
    sub     esp, 8\r
    sgdt    [esp]\r
    mov     eax, [esp + 2]\r
    xchg    eax, [esp]\r
    and     eax, 0FFFFh\r
    mov     [esp+4], eax\r
\r
;; UINT32  Ldtr, Tr;\r
    xor     eax, eax\r
    str     ax\r
    push    eax\r
    sldt    ax\r
    push    eax\r
\r
;; UINT32  EFlags;\r
    mov     eax, [ebp + 5 * 4]\r
    push    eax\r
\r
;; UINT32  Cr0, Cr1, Cr2, Cr3, Cr4;\r
    mov     eax, cr4\r
    or      eax, 208h\r
    mov     cr4, eax\r
    push    eax\r
    mov     eax, cr3\r
    push    eax\r
    mov     eax, cr2\r
    push    eax\r
    xor     eax, eax\r
    push    eax\r
    mov     eax, cr0\r
    push    eax\r
\r
;; UINT32  Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r
    mov     eax, dr7\r
    push    eax\r
    mov     eax, dr6\r
    push    eax\r
    mov     eax, dr3\r
    push    eax\r
    mov     eax, dr2\r
    push    eax\r
    mov     eax, dr1\r
    push    eax\r
    mov     eax, dr0\r
    push    eax\r
\r
;; FX_SAVE_STATE_IA32 FxSaveState;\r
    sub     esp, 512\r
    mov     edi, esp\r
    db      0fh, 0aeh, 07h ;fxsave [edi]\r
\r
;; UEFI calling convention for IA32 requires that Direction flag in EFLAGs is clear\r
    cld\r
\r
;; UINT32  ExceptionData;\r
    push    dword ptr [ebp + 2 * 4]\r
\r
;; Prepare parameter and call\r
    mov     edx, esp\r
    push    edx\r
    mov     edx, dword ptr [ebp + 1 * 4]\r
    push    edx\r
\r
    ;\r
    ; Call External Exception Handler\r
    ;\r
    mov     eax, CommonExceptionHandler\r
    call    eax\r
    add     esp, 8\r
\r
    cli\r
;; UINT32  ExceptionData;\r
    add     esp, 4\r
\r
;; FX_SAVE_STATE_IA32 FxSaveState;\r
    mov     esi, esp\r
    db      0fh, 0aeh, 0eh ; fxrstor [esi]\r
    add     esp, 512\r
\r
;; UINT32  Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r
;; Skip restoration of DRx registers to support in-circuit emualators\r
;; or debuggers set breakpoint in interrupt/exception context\r
    add     esp, 4 * 6\r
\r
;; UINT32  Cr0, Cr1, Cr2, Cr3, Cr4;\r
    pop     eax\r
    mov     cr0, eax\r
    add     esp, 4    ; not for Cr1\r
    pop     eax\r
    mov     cr2, eax\r
    pop     eax\r
    mov     cr3, eax\r
    pop     eax\r
    mov     cr4, eax\r
\r
;; UINT32  EFlags;\r
    pop     dword ptr [ebp + 5 * 4]\r
\r
;; UINT32  Ldtr, Tr;\r
;; UINT32  Gdtr[2], Idtr[2];\r
;; Best not let anyone mess with these particular registers...\r
    add     esp, 24\r
\r
;; UINT32  Eip;\r
    pop     dword ptr [ebp + 3 * 4]\r
\r
;; UINT32  Gs, Fs, Es, Ds, Cs, Ss;\r
;; NOTE - modified segment registers could hang the debugger...  We\r
;;        could attempt to insulate ourselves against this possibility,\r
;;        but that poses risks as well.\r
;;\r
    pop     gs\r
    pop     fs\r
    pop     es\r
    pop     ds\r
    pop     dword ptr [ebp + 4 * 4]\r
    pop     ss\r
\r
;; UINT32  Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;\r
    pop     edi\r
    pop     esi\r
    add     esp, 4   ; not for ebp\r
    add     esp, 4   ; not for esp\r
    pop     ebx\r
    pop     edx\r
    pop     ecx\r
    pop     eax\r
\r
    pop     dword ptr [ebp - 8]\r
    pop     dword ptr [ebp - 4]\r
    mov     esp, ebp\r
    pop     ebp\r
    add     esp, 8\r
    cmp     dword ptr [esp - 16], 0   ; check EXCEPTION_HANDLER_CONTEXT.OldIdtHandler\r
    jz      DoReturn\r
    cmp     dword ptr [esp - 20], 1   ; check EXCEPTION_HANDLER_CONTEXT.ExceptionDataFlag\r
    jz      ErrorCode\r
    jmp     dword ptr [esp - 16]\r
ErrorCode:\r
    sub     esp, 4\r
    jmp     dword ptr [esp - 12]\r
\r
DoReturn:    \r
    cmp     mDoFarReturnFlag, 0   ; Check if need to do far return instead of IRET\r
    jz      DoIret\r
    push    [esp + 8]    ; save EFLAGS\r
    add     esp, 16\r
    push    [esp - 8]    ; save CS in new location\r
    push    [esp - 8]    ; save EIP in new location\r
    push    [esp - 8]    ; save EFLAGS in new location\r
    popfd                ; restore EFLAGS\r
    retf                 ; far return\r
\r
DoIret:\r
    iretd\r
\r
CommonInterruptEntry ENDP\r
\r
;---------------------------------------;\r
; _AsmGetTemplateAddressMap                  ;\r
;----------------------------------------------------------------------------;\r
; \r
; Protocol prototype\r
;   AsmGetTemplateAddressMap (\r
;     EXCEPTION_HANDLER_TEMPLATE_MAP *AddressMap\r
;   );\r
;           \r
; Routine Description:\r
; \r
;  Return address map of interrupt handler template so that C code can generate\r
;  interrupt table.\r
; \r
; Arguments:\r
; \r
; \r
; Returns: \r
; \r
;   Nothing\r
;\r
; \r
; Input:  [ebp][0]  = Original ebp\r
;         [ebp][4]  = Return address\r
;          \r
; Output: Nothing\r
;           \r
; Destroys: Nothing\r
;-----------------------------------------------------------------------------;\r
AsmGetTemplateAddressMap  proc near public\r
    push    ebp                 ; C prolog\r
    mov     ebp, esp\r
    pushad\r
\r
    mov ebx, dword ptr [ebp + 08h]\r
    mov dword ptr [ebx],      AsmIdtVectorBegin\r
    mov dword ptr [ebx + 4h], (AsmIdtVectorEnd - AsmIdtVectorBegin) / 32\r
    mov dword ptr [ebx + 8h], HookAfterStubBegin\r
  \r
    popad\r
    pop     ebp\r
    ret\r
AsmGetTemplateAddressMap  ENDP\r
\r
;-------------------------------------------------------------------------------------\r
;  AsmVectorNumFixup (*VectorBase, VectorNum);\r
;-------------------------------------------------------------------------------------\r
AsmVectorNumFixup   proc near public\r
    mov     eax, dword ptr [esp + 8]\r
    mov     ecx, [esp + 4]\r
    mov     [ecx + (VectorNum - HookAfterStubBegin)], al\r
    ret\r
AsmVectorNumFixup   ENDP\r
END\r
Commit	Line	Data
8f07f895	1	;------------------------------------------------------------------------------ ;\r
e41aad15	2	; Copyright (c) 2012 - 2013, Intel Corporation. All rights reserved.<BR>\r
8f07f895	3	; This program and the accompanying materials\r
	4	; are licensed and made available under the terms and conditions of the BSD License\r
	5	; which accompanies this distribution. The full text of the license may be found at\r
	6	; http://opensource.org/licenses/bsd-license.php.\r
	7	;\r
	8	; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	9	; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	10	;\r
	11	; Module Name:\r
	12	;\r
	13	; ExceptionHandlerAsm.Asm\r
	14	;\r
	15	; Abstract:\r
	16	;\r
	17	; IA32 CPU Exception Handler\r
	18	;\r
	19	; Notes:\r
	20	;\r
	21	;------------------------------------------------------------------------------\r
	22	\r
	23	.686\r
	24	.model flat,C\r
	25	\r
	26	;\r
	27	; CommonExceptionHandler()\r
	28	;\r
	29	CommonExceptionHandler PROTO C\r
	30	\r
	31	.data\r
	32	\r
e41aad15 JF	33	EXTRN mErrorCodeFlag:DWORD ; Error code flags for exceptions\r
e41aad15 JF	34	EXTRN mDoFarReturnFlag:DWORD ; Do far return flag\r
8f07f895	35	\r
	36	.code\r
	37	\r
e41aad15 JF	38	ALIGN 8\r
e41aad15 JF	39	\r
8f07f895	40	;\r
	41	; exception handler stub table\r
	42	;\r
e41aad15 JF	43	AsmIdtVectorBegin:\r
	44	REPEAT 32\r
	45	db 6ah ; push #VectorNum\r
	46	db ($ - AsmIdtVectorBegin) / ((AsmIdtVectorEnd - AsmIdtVectorBegin) / 32) ; VectorNum\r
	47	push eax\r
	48	mov eax, CommonInterruptEntry\r
	49	jmp eax\r
	50	ENDM\r
	51	AsmIdtVectorEnd:\r
	52	\r
	53	HookAfterStubBegin:\r
	54	db 6ah ; push\r
	55	VectorNum:\r
	56	db 0 ; 0 will be fixed \r
	57	push eax\r
	58	mov eax, HookAfterStubHeaderEnd\r
	59	jmp eax\r
	60	HookAfterStubHeaderEnd:\r
	61	pop eax\r
	62	sub esp, 8 ; reserve room for filling exception data later\r
	63	push [esp + 8]\r
	64	xchg ecx, [esp] ; get vector number\r
	65	bt mErrorCodeFlag, ecx\r
	66	jnc @F\r
	67	push [esp] ; addition push if exception data needed\r
	68	@@:\r
	69	xchg ecx, [esp] ; restore ecx\r
	70	push eax\r
8f07f895	71	\r
	72	;----------------------------------------------------------------------------;\r
	73	; CommonInterruptEntry ;\r
	74	;----------------------------------------------------------------------------;\r
	75	; The follow algorithm is used for the common interrupt routine.\r
	76	; Entry from each interrupt with a push eax and eax=interrupt number\r
e41aad15 JF	77	; Stack:\r
	78	; +---------------------+\r
	79	; + EFlags +\r
	80	; +---------------------+\r
	81	; + CS +\r
	82	; +---------------------+\r
	83	; + EIP +\r
	84	; +---------------------+\r
	85	; + Error Code +\r
	86	; +---------------------+\r
	87	; + Vector Number +\r
	88	; +---------------------+\r
	89	; + EBP +\r
	90	; +---------------------+ <-- EBP\r
8f07f895	91	CommonInterruptEntry PROC PUBLIC\r
8f07f895	92	cli\r
e41aad15	93	pop eax\r
8f07f895	94	;\r
	95	; All interrupt handlers are invoked through interrupt gates, so\r
	96	; IF flag automatically cleared at the entry point\r
	97	;\r
	98	\r
	99	;\r
e41aad15	100	; Get vector number from top of stack\r
8f07f895	101	;\r
8f07f895	102	xchg ecx, [esp]\r
e41aad15	103	and ecx, 0FFh ; Vector number should be less than 256\r
8f07f895	104	cmp ecx, 32 ; Intel reserved vector for exceptions?\r
	105	jae NoErrorCode\r
	106	bt mErrorCodeFlag, ecx\r
	107	jc HasErrorCode\r
	108	\r
	109	NoErrorCode:\r
	110	\r
	111	;\r
	112	; Stack:\r
	113	; +---------------------+\r
	114	; + EFlags +\r
	115	; +---------------------+\r
	116	; + CS +\r
	117	; +---------------------+\r
	118	; + EIP +\r
	119	; +---------------------+\r
	120	; + ECX +\r
	121	; +---------------------+ <-- ESP\r
	122	;\r
	123	; Registers:\r
	124	; ECX - Vector Number\r
	125	;\r
	126	\r
	127	;\r
	128	; Put Vector Number on stack\r
	129	;\r
	130	push ecx\r
	131	\r
	132	;\r
	133	; Put 0 (dummy) error code on stack, and restore ECX\r
	134	;\r
	135	xor ecx, ecx ; ECX = 0\r
	136	xchg ecx, [esp+4]\r
	137	\r
	138	jmp ErrorCodeAndVectorOnStack\r
	139	\r
	140	HasErrorCode:\r
	141	\r
	142	;\r
	143	; Stack:\r
	144	; +---------------------+\r
	145	; + EFlags +\r
	146	; +---------------------+\r
	147	; + CS +\r
	148	; +---------------------+\r
	149	; + EIP +\r
	150	; +---------------------+\r
	151	; + Error Code +\r
	152	; +---------------------+\r
	153	; + ECX +\r
	154	; +---------------------+ <-- ESP\r
	155	;\r
	156	; Registers:\r
	157	; ECX - Vector Number\r
	158	;\r
	159	\r
	160	;\r
	161	; Put Vector Number on stack and restore ECX\r
	162	;\r
	163	xchg ecx, [esp]\r
	164	\r
8f07f895	165	ErrorCodeAndVectorOnStack:\r
	166	push ebp\r
	167	mov ebp, esp\r
	168	\r
	169	;\r
	170	; Stack:\r
	171	; +---------------------+\r
	172	; + EFlags +\r
	173	; +---------------------+\r
	174	; + CS +\r
	175	; +---------------------+\r
	176	; + EIP +\r
	177	; +---------------------+\r
	178	; + Error Code +\r
	179	; +---------------------+\r
	180	; + Vector Number +\r
	181	; +---------------------+\r
	182	; + EBP +\r
	183	; +---------------------+ <-- EBP\r
	184	;\r
	185	\r
	186	;\r
	187	; Align stack to make sure that EFI_FX_SAVE_STATE_IA32 of EFI_SYSTEM_CONTEXT_IA32\r
	188	; is 16-byte aligned\r
	189	;\r
	190	and esp, 0fffffff0h\r
	191	sub esp, 12\r
	192	\r
e41aad15 JF	193	sub esp, 8\r
	194	push 0 ; clear EXCEPTION_HANDLER_CONTEXT.OldIdtHandler\r
	195	push 0 ; clear EXCEPTION_HANDLER_CONTEXT.ExceptionDataFlag\r
	196	\r
8f07f895	197	;; UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;\r
	198	push eax\r
	199	push ecx\r
	200	push edx\r
	201	push ebx\r
	202	lea ecx, [ebp + 6 * 4]\r
	203	push ecx ; ESP\r
	204	push dword ptr [ebp] ; EBP\r
	205	push esi\r
	206	push edi\r
	207	\r
	208	;; UINT32 Gs, Fs, Es, Ds, Cs, Ss;\r
	209	mov eax, ss\r
	210	push eax\r
	211	movzx eax, word ptr [ebp + 4 * 4]\r
	212	push eax\r
	213	mov eax, ds\r
	214	push eax\r
	215	mov eax, es\r
	216	push eax\r
	217	mov eax, fs\r
	218	push eax\r
	219	mov eax, gs\r
	220	push eax\r
	221	\r
	222	;; UINT32 Eip;\r
	223	mov eax, [ebp + 3 * 4]\r
	224	push eax\r
	225	\r
	226	;; UINT32 Gdtr[2], Idtr[2];\r
	227	sub esp, 8\r
	228	sidt [esp]\r
	229	mov eax, [esp + 2]\r
	230	xchg eax, [esp]\r
	231	and eax, 0FFFFh\r
	232	mov [esp+4], eax\r
	233	\r
	234	sub esp, 8\r
	235	sgdt [esp]\r
	236	mov eax, [esp + 2]\r
	237	xchg eax, [esp]\r
	238	and eax, 0FFFFh\r
	239	mov [esp+4], eax\r
	240	\r
	241	;; UINT32 Ldtr, Tr;\r
	242	xor eax, eax\r
	243	str ax\r
	244	push eax\r
	245	sldt ax\r
	246	push eax\r
	247	\r
	248	;; UINT32 EFlags;\r
	249	mov eax, [ebp + 5 * 4]\r
	250	push eax\r
	251	\r
	252	;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;\r
	253	mov eax, cr4\r
	254	or eax, 208h\r
	255	mov cr4, eax\r
	256	push eax\r
	257	mov eax, cr3\r
	258	push eax\r
	259	mov eax, cr2\r
	260	push eax\r
261	xor eax, eax\r
262	push eax\r
263	mov eax, cr0\r
264	push eax\r
265	\r
266	;; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r
267	mov eax, dr7\r
268	push eax\r
269	mov eax, dr6\r
270	push eax\r
271	mov eax, dr3\r
272	push eax\r
273	mov eax, dr2\r
274	push eax\r
275	mov eax, dr1\r
276	push eax\r
277	mov eax, dr0\r
278	push eax\r
279	\r
280	;; FX_SAVE_STATE_IA32 FxSaveState;\r
281	sub esp, 512\r
282	mov edi, esp\r
283	db 0fh, 0aeh, 07h ;fxsave [edi]\r
284	\r
285	;; UEFI calling convention for IA32 requires that Direction flag in EFLAGs is clear\r
286	cld\r
287	\r
288	;; UINT32 ExceptionData;\r
289	push dword ptr [ebp + 2 * 4]\r
290	\r
291	;; Prepare parameter and call\r
292	mov edx, esp\r
293	push edx\r
294	mov edx, dword ptr [ebp + 1 * 4]\r
295	push edx\r
296	\r
297	;\r
298	; Call External Exception Handler\r
299	;\r
300	mov eax, CommonExceptionHandler\r
301	call eax\r
302	add esp, 8\r
303	\r
304	cli\r
305	;; UINT32 ExceptionData;\r
306	add esp, 4\r
307	\r
308	;; FX_SAVE_STATE_IA32 FxSaveState;\r
309	mov esi, esp\r
310	db 0fh, 0aeh, 0eh ; fxrstor [esi]\r
311	add esp, 512\r
312	\r
313	;; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;\r
314	;; Skip restoration of DRx registers to support in-circuit emualators\r
315	;; or debuggers set breakpoint in interrupt/exception context\r
316	add esp, 4 * 6\r
317	\r
318	;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;\r
319	pop eax\r
320	mov cr0, eax\r
321	add esp, 4 ; not for Cr1\r
322	pop eax\r
323	mov cr2, eax\r
324	pop eax\r
325	mov cr3, eax\r
326	pop eax\r
327	mov cr4, eax\r
328	\r
329	;; UINT32 EFlags;\r
330	pop dword ptr [ebp + 5 * 4]\r
331	\r
332	;; UINT32 Ldtr, Tr;\r
333	;; UINT32 Gdtr[2], Idtr[2];\r
334	;; Best not let anyone mess with these particular registers...\r
335	add esp, 24\r
336	\r
337	;; UINT32 Eip;\r
338	pop dword ptr [ebp + 3 * 4]\r
339	\r
340	;; UINT32 Gs, Fs, Es, Ds, Cs, Ss;\r
341	;; NOTE - modified segment registers could hang the debugger... We\r
342	;; could attempt to insulate ourselves against this possibility,\r
343	;; but that poses risks as well.\r
344	;;\r
345	pop gs\r
346	pop fs\r
347	pop es\r
348	pop ds\r
349	pop dword ptr [ebp + 4 * 4]\r
350	pop ss\r
351	\r
352	;; UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;\r
353	pop edi\r
354	pop esi\r
355	add esp, 4 ; not for ebp\r
356	add esp, 4 ; not for esp\r
357	pop ebx\r
358	pop edx\r
359	pop ecx\r
360	pop eax\r
361	\r
e41aad15 JF	362	pop dword ptr [ebp - 8]\r
e41aad15 JF	363	pop dword ptr [ebp - 4]\r
8f07f895	364	mov esp, ebp\r
	365	pop ebp\r
	366	add esp, 8\r
e41aad15 JF	367	cmp dword ptr [esp - 16], 0 ; check EXCEPTION_HANDLER_CONTEXT.OldIdtHandler\r
	368	jz DoReturn\r
	369	cmp dword ptr [esp - 20], 1 ; check EXCEPTION_HANDLER_CONTEXT.ExceptionDataFlag\r
	370	jz ErrorCode\r
	371	jmp dword ptr [esp - 16]\r
	372	ErrorCode:\r
	373	sub esp, 4\r
	374	jmp dword ptr [esp - 12]\r
	375	\r
	376	DoReturn: \r
	377	cmp mDoFarReturnFlag, 0 ; Check if need to do far return instead of IRET\r
	378	jz DoIret\r
	379	push [esp + 8] ; save EFLAGS\r
	380	add esp, 16\r
	381	push [esp - 8] ; save CS in new location\r
	382	push [esp - 8] ; save EIP in new location\r
	383	push [esp - 8] ; save EFLAGS in new location\r
	384	popfd ; restore EFLAGS\r
	385	retf ; far return\r
	386	\r
	387	DoIret:\r
8f07f895	388	iretd\r
	389	\r
	390	CommonInterruptEntry ENDP\r
	391	\r
	392	;---------------------------------------;\r
e41aad15	393	; _AsmGetTemplateAddressMap ;\r
8f07f895	394	;----------------------------------------------------------------------------;\r
	395	; \r
	396	; Protocol prototype\r
e41aad15	397	; AsmGetTemplateAddressMap (\r
8f07f895	398	; EXCEPTION_HANDLER_TEMPLATE_MAP *AddressMap\r
	399	; );\r
	400	; \r
	401	; Routine Description:\r
	402	; \r
	403	; Return address map of interrupt handler template so that C code can generate\r
	404	; interrupt table.\r
	405	; \r
	406	; Arguments:\r
	407	; \r
	408	; \r
	409	; Returns: \r
	410	; \r
	411	; Nothing\r
	412	;\r
	413	; \r
	414	; Input: [ebp][0] = Original ebp\r
	415	; [ebp][4] = Return address\r
	416	; \r
	417	; Output: Nothing\r
	418	; \r
	419	; Destroys: Nothing\r
	420	;-----------------------------------------------------------------------------;\r
e41aad15	421	AsmGetTemplateAddressMap proc near public\r
8f07f895	422	push ebp ; C prolog\r
	423	mov ebp, esp\r
	424	pushad\r
	425	\r
e41aad15 JF	426	mov ebx, dword ptr [ebp + 08h]\r
	427	mov dword ptr [ebx], AsmIdtVectorBegin\r
	428	mov dword ptr [ebx + 4h], (AsmIdtVectorEnd - AsmIdtVectorBegin) / 32\r
	429	mov dword ptr [ebx + 8h], HookAfterStubBegin\r
8f07f895	430	\r
	431	popad\r
	432	pop ebp\r
	433	ret\r
e41aad15 JF	434	AsmGetTemplateAddressMap ENDP\r
	435	\r
	436	;-------------------------------------------------------------------------------------\r
	437	; AsmVectorNumFixup (*VectorBase, VectorNum);\r
	438	;-------------------------------------------------------------------------------------\r
	439	AsmVectorNumFixup proc near public\r
	440	mov eax, dword ptr [esp + 8]\r
	441	mov ecx, [esp + 4]\r
	442	mov [ecx + (VectorNum - HookAfterStubBegin)], al\r
	443	ret\r
	444	AsmVectorNumFixup ENDP\r
8f07f895	445	END\r