diff options
Diffstat (limited to 'MdePkg/Library/BaseLib/X64/Thunk16.nasm')
-rw-r--r-- | MdePkg/Library/BaseLib/X64/Thunk16.nasm | 76 |
1 files changed, 38 insertions, 38 deletions
diff --git a/MdePkg/Library/BaseLib/X64/Thunk16.nasm b/MdePkg/Library/BaseLib/X64/Thunk16.nasm index edd418c15a..cabe9d94d1 100644 --- a/MdePkg/Library/BaseLib/X64/Thunk16.nasm +++ b/MdePkg/Library/BaseLib/X64/Thunk16.nasm @@ -57,7 +57,7 @@ SECTION .data ; These are global constant to convey information to C code.
;
ASM_PFX(m16Size) DW InternalAsmThunk16 - ASM_PFX(m16Start)
-ASM_PFX(mThunk16Attr) DW _ThunkAttr - ASM_PFX(m16Start)
+ASM_PFX(mThunk16Attr) DW _BackFromUserCode.ThunkAttr - ASM_PFX(m16Start)
ASM_PFX(m16Gdt) DW _NullSeg - ASM_PFX(m16Start)
ASM_PFX(m16GdtrBase) DW _16GdtrBase - ASM_PFX(m16Start)
ASM_PFX(mTransition) DW _EntryPoint - ASM_PFX(m16Start)
@@ -86,8 +86,8 @@ _BackFromUserCode: DB 16h ; push ss
DB 0eh ; push cs
DB 66h
- call @Base ; push eip
-@Base:
+ call .Base ; push eip
+.Base:
DB 66h
push 0 ; reserved high order 32 bits of EFlags
pushfw ; pushfd actually
@@ -98,19 +98,19 @@ _BackFromUserCode: DB 1eh ; push ds
DB 66h, 60h ; pushad
DB 66h, 0bah ; mov edx, imm32
-_ThunkAttr: dd 0
+.ThunkAttr: dd 0
test dl, THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15
- jz @1
+ jz .1
mov eax, 15cd2401h ; mov ax, 2401h & int 15h
cli ; disable interrupts
- jnc @2
-@1:
+ jnc .2
+.1:
test dl, THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL
- jz @2
+ jz .2
in al, 92h
or al, 2
out 92h, al ; deactivate A20M#
-@2:
+.2:
xor ax, ax ; xor eax, eax
mov eax, ss ; mov ax, ss
lea bp, [esp + IA32_REGS.size]
@@ -124,32 +124,32 @@ _ThunkAttr: dd 0 add bp, ax ; add ebp, eax
mov ax, cs
shl ax, 4
- lea ax, [eax + ebx + (@64BitCode - @Base)]
- DB 66h, 2eh, 89h, 87h ; mov cs:[bx + (@64Eip - @Base)], eax
- DW @64Eip - @Base
+ lea ax, [eax + ebx + (.64BitCode - .Base)]
+ DB 66h, 2eh, 89h, 87h ; mov cs:[bx + (.64Eip - .Base)], eax
+ DW .64Eip - .Base
DB 66h, 0b8h ; mov eax, imm32
-SavedCr4: DD 0
+.SavedCr4: DD 0
mov cr4, rax
;
; rdi in the instruction below is indeed bx in 16-bit code
;
DB 66h, 2eh ; 2eh is "cs:" segment override
- lgdt [rdi + (SavedGdt - @Base)]
+ lgdt [rdi + (SavedGdt - .Base)]
DB 66h
mov ecx, 0c0000080h
rdmsr
or ah, 1
wrmsr
DB 66h, 0b8h ; mov eax, imm32
-SavedCr0: DD 0
+.SavedCr0: DD 0
mov cr0, rax
- DB 66h, 0eah ; jmp far cs:@64Bit
-@64Eip: DD 0
-SavedCs: DW 0
-@64BitCode:
+ DB 66h, 0eah ; jmp far cs:.64Bit
+.64Eip: DD 0
+.SavedCs: DW 0
+.64BitCode:
db 090h
db 048h, 0bch ; mov rsp, imm64
-SavedSp: DQ 0 ; restore stack
+.SavedSp: DQ 0 ; restore stack
nop
ret
@@ -184,16 +184,16 @@ _ToUserCode: mov ss, esi ; set up 16-bit stack segment
mov sp, bx ; set up 16-bit stack pointer
DB 66h ; make the following call 32-bit
- call @ToUserCodeBase ; push eip
-@ToUserCodeBase:
- pop bp ; ebp <- address of @ToUserCodeBase
+ call .Base ; push eip
+.Base:
+ pop bp ; ebp <- address of .Base
push qword [esp + IA32_REGS.size + 2]
- lea eax, [rsi + (@RealMode - @ToUserCodeBase)] ; rsi is "bp" in 16-bit code
+ lea eax, [rsi + (.RealMode - .Base)] ; rsi is "bp" in 16-bit code
push rax
retf ; execution begins at next instruction
-@RealMode:
+.RealMode:
DB 66h, 2eh ; CS and operand size override
- lidt [rsi + (_16Idtr - @ToUserCodeBase)]
+ lidt [rsi + (_16Idtr - .Base)]
DB 66h, 61h ; popad
DB 1fh ; pop ds
DB 07h ; pop es
@@ -269,7 +269,7 @@ ASM_PFX(InternalAsmThunk16): add edi, eax ; edi <- linear address of 16-bit stack
pop rcx
rep movsd ; copy RegSet
- lea ecx, [rdx + (SavedCr4 - ASM_PFX(m16Start))]
+ lea ecx, [rdx + (_BackFromUserCode.SavedCr4 - ASM_PFX(m16Start))]
mov eax, edx ; eax <- transition code address
and edx, 0fh
shl eax, 12 ; segment address in high order 16 bits
@@ -278,11 +278,11 @@ ASM_PFX(InternalAsmThunk16): sgdt [rsp + 60h] ; save GDT stack in argument space
movzx r10, word [rsp + 60h] ; r10 <- GDT limit
- lea r11, [rcx + (InternalAsmThunk16 - SavedCr4) + 0xf]
+ lea r11, [rcx + (InternalAsmThunk16 - _BackFromUserCode.SavedCr4) + 0xf]
and r11, ~0xf ; r11 <- 16-byte aligned shadowed GDT table in real mode buffer
- mov [rcx + (SavedGdt - SavedCr4)], r10w ; save the limit of shadowed GDT table
- mov [rcx + (SavedGdt - SavedCr4) + 2], r11 ; save the base address of shadowed GDT table
+ mov [rcx + (SavedGdt - _BackFromUserCode.SavedCr4)], r10w ; save the limit of shadowed GDT table
+ mov [rcx + (SavedGdt - _BackFromUserCode.SavedCr4) + 2], r11 ; save the base address of shadowed GDT table
mov rsi, [rsp + 62h] ; rsi <- the original GDT base address
xchg rcx, r10 ; save rcx to r10 and initialize rcx to be the limit of GDT table
@@ -294,25 +294,25 @@ ASM_PFX(InternalAsmThunk16): sidt [rsp + 50h] ; save IDT stack in argument space
mov rax, cr0
- mov [rcx + (SavedCr0 - SavedCr4)], eax
+ mov [rcx + (_BackFromUserCode.SavedCr0 - _BackFromUserCode.SavedCr4)], eax
and eax, 7ffffffeh ; clear PE, PG bits
mov rbp, cr4
- mov [rcx], ebp ; save CR4 in SavedCr4
+ mov [rcx], ebp ; save CR4 in _BackFromUserCode.SavedCr4
and ebp, ~30h ; clear PAE, PSE bits
mov esi, r8d ; esi <- 16-bit stack segment
DB 6ah, DATA32 ; push DATA32
pop rdx ; rdx <- 32-bit data segment selector
- lgdt [rcx + (_16Gdtr - SavedCr4)]
+ lgdt [rcx + (_16Gdtr - _BackFromUserCode.SavedCr4)]
mov ss, edx
pushfq
lea edx, [rdx + DATA16 - DATA32]
- lea r8, [REL @RetFromRealMode]
+ lea r8, [REL .RetFromRealMode]
push r8
mov r8d, cs
- mov [rcx + (SavedCs - SavedCr4)], r8w
- mov [rcx + (SavedSp - SavedCr4)], rsp
- jmp dword far [rcx + (_EntryPoint - SavedCr4)]
-@RetFromRealMode:
+ mov [rcx + (_BackFromUserCode.SavedCs - _BackFromUserCode.SavedCr4)], r8w
+ mov [rcx + (_BackFromUserCode.SavedSp - _BackFromUserCode.SavedCr4)], rsp
+ jmp dword far [rcx + (_EntryPoint - _BackFromUserCode.SavedCr4)]
+.RetFromRealMode:
popfq
lgdt [rsp + 60h] ; restore protected mode GDTR
lidt [rsp + 50h] ; restore protected mode IDTR
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