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Diffstat (limited to 'ReferenceCode/Haswell/Library/ThunkLib/Ia32/Thunk16.asm')
| -rw-r--r-- | ReferenceCode/Haswell/Library/ThunkLib/Ia32/Thunk16.asm | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/ReferenceCode/Haswell/Library/ThunkLib/Ia32/Thunk16.asm b/ReferenceCode/Haswell/Library/ThunkLib/Ia32/Thunk16.asm new file mode 100644 index 0000000..af9d34c --- /dev/null +++ b/ReferenceCode/Haswell/Library/ThunkLib/Ia32/Thunk16.asm @@ -0,0 +1,238 @@ +;/*++ +; This file contains an 'Intel Peripheral Driver' and is +; licensed for Intel CPUs and chipsets under the terms of your +; license agreement with Intel or your vendor. This file may +; be modified by the user, subject to additional terms of the +; license agreement +;--*/ +;------------------------------------------------------------------------------ +; +; Copyright (c) 2006 - 2011 Intel Corporation. All rights reserved +; This software and associated documentation (if any) is furnished +; under a license and may only be used or copied in accordance +; with the terms of the license. Except as permitted by such +; license, no part of this software or documentation may be +; reproduced, stored in a retrieval system, or transmitted in any +; form or by any means without the express written consent of +; Intel Corporation. +; +; Module Name: +; +; Thunk.asm +; +; Abstract: +; +; Real mode thunk +; +;------------------------------------------------------------------------------ + + .686p + .model flat,C + .const + +EXTERNDEF mCode16Size:DWORD +mCode16Size DD _Code16End - _Code16Addr + + .data + ALIGN 10h + +NullSegSel DQ 0 +_16CsSegSel LABEL QWORD + DW -1 + DW 0 + DB 0 + DB 9Bh + DB 8Fh ; 16-bit segment, 4GB limit + DB 0 +;_16DsSegSel LABEL QWORD +; DW -1 +; DW 0 +; DB 0 +; DB 93h +; DB 8Fh ; 16-bit segment, 4GB limit +; DB 0 +_16Gdtr LABEL FWORD + DW $ - offset NullSegSel - 1 + DD offset NullSegSel + + .code + +IA32_REGS STRUC 4t +_EDI DD ? +_ESI DD ? +_EBP DD ? +_ESP DD ? +_EBX DD ? +_EDX DD ? +_ECX DD ? +_EAX DD ? +_DS DW ? +_ES DW ? +_FS DW ? +_GS DW ? +_EFLAGS DD ? +_EIP DD ? +_CS DW ? +_SS DW ? +IA32_REGS ENDS + +_STK16 STRUC 1t +RetEip DD ? +RetCs DW ? +ThunkFlags DW ? +SavedGdtr FWORD ? +Resvd1 DW ? +SavedCr0 DD ? +SavedCr4 DD ? +_STK16 ENDS + +; IA32_REGISTER_SET * +; EFIAPI +; _Thunk16 ( +; IN OUT IA32_REGISTER_SET *RegisterSet, +; IN UINT32 ThunkFlags, +; IN UINT32 RealModeCs +; ); +_Thunk16 PROC USES DS ES FS GS EDI ESI EBP EBX EDX ECX ; 10 dwords will be pushed + mov ebp, esp + add ebp, 40 + mov ORG_SS, ss ; preserve SS & ESP + mov ORG_ESP, esp + + mov esi, [ebp + 4] ; esi <- RegisterSet + movzx edx, (IA32_REGS ptr [esi])._SS ; find 16-bit stack linear address + shl edx, 4 + add edx, (IA32_REGS ptr [esi])._ESP + add edx, - sizeof (IA32_REGS) - sizeof (_STK16) ; edx <- 16-bit stack linear address + + mov edi, edx ; [RealMode.IA32_REGS] <- RegisterSet + push sizeof (IA32_REGS) / 4 + pop ecx + rep movsd + lea eax, @F ; [RealMode._STK16.RetEip] <- ReturnOffset + stosd + mov eax, cs ; [RealMode._STK16.RetCs] <- ReturnSegment + stosw + mov eax, [ebp + 8] ; [RealMode._STK16.ThunkFlags] <- ThunkFlags + stosw + sgdt dword ptr [edi] ; [RealMode._STK16.SavedGdtr] <- GDTR + add edi, 8 + mov eax, cr0 ; [RealMode._STK16.SavedCr0] <- CR0 + stosd + mov esi, eax ; esi <- CR0 to set + and esi, 07FFFFFFEh ; clear BIT[24, 0]: PE & PG bits + mov eax, cr4 ; [RealMode._STK16.SavedCr4] <- CR4 + stosd + + push word ptr [ebp + 12] ; [STACK] <- RealModeCs, far jump address for into RealMode + pushw 0 + pushd 8 ; transfer program control to a readable segment that has a limit of 64KB + pushd offset @16Bit + mov edi, edx ; edi <- 16-bit stack linear address + + sidt fword ptr [ebp + 8] ; save IDTR + lgdt _16Gdtr + retf +@16Bit: + mov cr0, esi ; disable PE & PG +; db 066h +; mov ecx, 0C0000080h +; rdmsr +; and ah, NOT 1 +; wrmsr ; clear LME bit + mov eax, cr4 + and al, not 030h ; clear PAE & PSE + mov cr4, eax + retf +@@: + xor eax, eax + mov eax, ss + shl eax, 4 + add eax, esp ; [EAX] <- RegisterSet after x86 call..to return the execution result + mov ss, cs:word ptr [ORG_SS] ; restore SS & ESP + mov esp, cs:dword ptr [ORG_ESP] + lidt fword ptr [ebp + 8] ; restore IDTR + + ret + +ORG_SS DW ? +ORG_ESP DD ? + +_Thunk16 ENDP + + ALIGN 10h + +; VOID +; EFIAPI +; _Code16Addr ( +; VOID +; ); +_Code16Addr PROC +_Code16Addr ENDP + +; Input: EDI <- 16-bit stack linear address +RealMode PROC + db 066h ; movzx esp, di + movzx esp, di + db 033h, 0FFh ; xor di, di + db 066h ; shr edi, 4 + shr edi, 4 + mov ss, di ; mov ss, di + + db 02Eh, 00Fh, 001, 01Eh ; lidt cs:[_16Idtr] + dw (_16Idtr - _Code16Addr) + db 066h ; popad + popa + pop ds + pop es + pop fs + pop gs + add esp, 4 ; skip EFLAGS + + ; test if EFLAGS with _THUNK_INTERRUPT + db 067h, 00F7h, 044h, 024h, 00Eh, 001h, 000h ; test [esp + 0Eh] + jz @F + db 09Ch ; pushf +@@: + push cs + db 068h ; pushw + dw (@FarCallRet - _Code16Addr) + jz @F + db 066h, 067h + jmp fword ptr [esp + 6] +@@: + db 066h, 067h + jmp fword ptr [esp + 4] +@FarCallRet: + pushf ; pushfd actually + push gs + push fs + push es + push ds + db 066h ; pushad + pusha + cli + + db 066h, 067h + lgdt (_STK16 ptr [esp + sizeof(IA32_REGS)]).SavedGdtr + db 066h, 067h + mov eax, (_STK16 ptr [esp + sizeof(IA32_REGS)]).SavedCr4 + mov cr4, eax +; db 066h +; mov ecx, 0C0000080h +; rdmsr +; or ah, 1 +; wrmsr ; set LME + db 066h, 067h + mov eax, (_STK16 ptr [esp + sizeof(IA32_REGS)]).SavedCr0 + mov cr0, eax + db 066h, 067h + jmp fword ptr (_STK16 ptr [esp + sizeof(IA32_REGS)]).RetEip + +RealMode ENDP + +_16Idtr FWORD (1 shl 10) - 1 + +_Code16End: + + END |