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Diffstat (limited to 'ReferenceCode/Haswell/Library/ThunkLib/x64/Thunk16.asm')
| -rw-r--r-- | ReferenceCode/Haswell/Library/ThunkLib/x64/Thunk16.asm | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/ReferenceCode/Haswell/Library/ThunkLib/x64/Thunk16.asm b/ReferenceCode/Haswell/Library/ThunkLib/x64/Thunk16.asm new file mode 100644 index 0000000..89bb447 --- /dev/null +++ b/ReferenceCode/Haswell/Library/ThunkLib/x64/Thunk16.asm @@ -0,0 +1,216 @@ +;/*++ +; 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 - 2010 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 +; +;------------------------------------------------------------------------------ + +EXTERNDEF mCode16Size:QWORD + + .const + +mCode16Size DQ _Code16End - _Code16Addr + + .data + +NullSegSel DQ 0 +_16CsSegSel LABEL QWORD + DW -1 + DW 0 + DB 0 + DB 9bh + DB 8fh ; 16-bit segment + DB 0 + +_16Gdtr LABEL FWORD + DW $ - offset NullSegSel - 1 + DQ 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 ? +_RFLAGS DQ ? +_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 + +_Thunk16 PROC USES rbp rbx rsi rdi r12 r13 r14 r15 + + push fs + push gs + + mov r12d, ds + mov r13d, es + mov r14d, ss + mov r15, rsp + mov rsi, rcx + movzx r10, (IA32_REGS ptr [rsi])._SS + xor rdi, rdi + mov edi, (IA32_REGS ptr [rsi])._ESP + add rdi, - sizeof (IA32_REGS) - sizeof (_STK16) + push rdi + imul rax, r10, 16 + add rdi, rax + push sizeof (IA32_REGS) / 4 + pop rcx + rep movsd + pop rbx ; rbx <- 16-bit stack offset + lea eax, @F ; return offset + stosd + mov eax, cs ; return segment + stosw + mov eax, edx ; THUNK Flags + stosw + sgdt fword ptr [rsp + 58h] ; save GDTR + mov rax, [rsp + 58h] + stosq + mov rax, cr0 ; save CR0 + mov esi, eax ; esi <- CR0 to set + stosd + mov rax, cr4 ; save CR4 + stosd + sidt fword ptr [rsp + 58h] ; save IDTR + and esi, 07ffffffeh ;NOT 080000001h ; clear PE & PG bits + mov rdi, r10 ; rdi <- 16-bit stack segment + + shl r8, 16 + push r8 ; far jmp address + lea eax, @16Bit + push rax + mov word ptr [rsp + 4], 8 + lgdt _16Gdtr + retf +@16Bit: + mov cr0, rsi ; disable PE & PG + DB 66h + mov ecx, 0c0000080h + rdmsr + and ah, NOT 1 + wrmsr ; clear LME bit + mov rax, cr4 + and al, NOT 30h ; clear PAE & PSE + mov cr4, rax + retf +@@: + xor rax, rax + mov eax, ss + shl eax, 4 + add eax, esp ; rax <- address of 16-bit stack + mov rsp, r15 + lidt fword ptr [rsp + 58h] ; restore IDTR + mov ds, r12d + mov es, r13d + mov ss, r14d + pop gs + pop fs + ret +_Thunk16 ENDP + + ALIGN 10h + +_Code16Addr PROC +_Code16Addr ENDP + +RealMode PROC + mov ss, edi + mov sp, bx ; set up 16-bit stack + DB 2eh, 0fh, 1, 1eh + DW _16Idtr - _Code16Addr ; lidt _16Idtr + DB 66h, 61h ; popad + DB 1fh ; pop ds + DB 7 ; pop es + pop fs + pop gs + + add esp, 8 ; skip RFLAGS + DB 67h, 0f7h, 44h, 24h, 0eh, 1, 0 ; test [esp + 0eh], 1 + jz @F + pushfq ; pushf, actually +@@: + DB 0eh ; push cs + DB 68h ; push /iw + DW @FarCallRet - _Code16Addr + jz @F + DB 66h + jmp fword ptr [esp + 6] +@@: + DB 66h + jmp fword ptr [esp + 4] +@FarCallRet: + DB 66h + push 0 ; push a dword of zero + pushf ; pushfd, actually + push gs + push fs + DB 6 ; push es + DB 1eh ; push ds + DB 66h, 60h ; pushad + cli + + DB 66h + lgdt (_STK16 ptr [esp + sizeof(IA32_REGS)]).SavedGdtr + DB 66h + mov eax, (_STK16 ptr [esp + sizeof(IA32_REGS)]).SavedCr4 + mov cr4, rax + DB 66h + mov ecx, 0c0000080h + rdmsr + or ah, 1 + wrmsr ; set LME + DB 66h + mov eax, (_STK16 ptr [esp + sizeof(IA32_REGS)]).SavedCr0 + mov cr0, rax + DB 66h + jmp fword ptr (_STK16 ptr [esp + sizeof(IA32_REGS)]).RetEip + +RealMode ENDP + +_16Idtr FWORD (1 SHL 10) - 1 + +_Code16End: + + END |