Modified coding style, removed unnecessary comments and "offset" key words.

[mirror_edk2.git] / MdePkg / Library / BaseLib / X64 / Thunk16.asm

diff --git a/MdePkg/Library/BaseLib/X64/Thunk16.asm b/MdePkg/Library/BaseLib/X64/Thunk16.asm
index b3c0769f1f36099c9e703e85fb900575a3296232..b120434efb0c7ac3211ce433a89b21fa27adbc93 100644 (file)
--- a/MdePkg/Library/BaseLib/X64/Thunk16.asm
+++ b/MdePkg/Library/BaseLib/X64/Thunk16.asm
@@ -26,9 +26,6 @@ EXTERNDEF   m16Gdt:WORD
 EXTERNDEF   m16GdtrBase:WORD\r
 EXTERNDEF   mTransition:WORD\r
 \r
-;THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15     EQU 2\r
-;THUNK_ATTRIBUTE_DISABLE_A20_MASK_KBD_CTRL   EQU 4\r
-\r
 IA32_REGS   STRUC   4t\r
 _EDI        DD      ?\r
 _ESI        DD      ?\r
@@ -50,19 +47,19 @@ IA32_REGS   ENDS
 \r
     .const\r
 \r
-m16Size         DW      offset InternalAsmThunk16 - offset m16Start\r
-mThunk16Attr    DW      offset _ThunkAttr - offset m16Start\r
-m16Gdt          DW      offset _NullSegDesc - offset m16Start\r
-m16GdtrBase     DW      offset _16GdtrBase - offset m16Start\r
-mTransition     DW      offset _EntryPoint - offset m16Start\r
+m16Size         DW      InternalAsmThunk16 - m16Start\r
+mThunk16Attr    DW      _ThunkAttr - m16Start\r
+m16Gdt          DW      _NullSegDesc - m16Start\r
+m16GdtrBase     DW      _16GdtrBase - m16Start\r
+mTransition     DW      _EntryPoint - m16Start\r
 \r
     .code\r
 \r
 m16Start    LABEL   BYTE\r
 \r
-SavedGdt        LABEL   FWORD\r
-                DW      ?\r
-                DQ      ?\r
+SavedGdt    LABEL   FWORD\r
+            DW      ?\r
+            DQ      ?\r
 \r
 _BackFromUserCode   PROC\r
     DB      16h                         ; push ss\r
@@ -103,7 +100,7 @@ _ThunkAttr  DD      ?
 SavedCr4    DD      ?\r
     mov     cr4, rax\r
     DB      66h, 2eh\r
-    lgdt    fword ptr [rdi + (offset SavedGdt - offset @Base)]\r
+    lgdt    fword ptr [rdi + (SavedGdt - @Base)]\r
     DB      66h\r
     mov     ecx, 0c0000080h\r
     rdmsr\r
@@ -121,12 +118,12 @@ SavedEsp    DD      ?
     retf                                ; return to protected mode\r
 _BackFromUserCode   ENDP\r
 \r
-_EntryPoint     DD      offset _ToUserCode - offset m16Start\r
-                DW      8h\r
-_16Gdtr         LABEL   FWORD\r
-                DW      offset GdtEnd - offset _NullSegDesc - 1\r
-_16GdtrBase     DQ      offset _NullSegDesc\r
-_16Idtr         FWORD   (1 SHL 10) - 1\r
+_EntryPoint DD      _ToUserCode - m16Start\r
+            DW      8h\r
+_16Gdtr     LABEL   FWORD\r
+            DW      GdtEnd - _NullSegDesc - 1\r
+_16GdtrBase DQ      _NullSegDesc\r
+_16Idtr     FWORD   (1 SHL 10) - 1\r
 \r
 _ToUserCode PROC\r
     mov     edi, ss\r
@@ -147,18 +144,18 @@ _ToUserCode PROC
     DB      66h\r
     call    @Base                       ; push eip\r
 @Base:\r
-    pop     bp                          ; ebp <- offset @Base\r
+    pop     bp                          ; ebp <- address of @Base\r
     push    [esp + sizeof (IA32_REGS) + 2]\r
-    lea     eax, [rsi + (offset @RealMode - offset @Base)]\r
+    lea     eax, [rsi + (@RealMode - @Base)]\r
     push    rax\r
     retf\r
 @RealMode:\r
     DB      2eh                         ; cs:\r
-    mov     [rsi + (offset SavedSs - offset @Base)], edi\r
+    mov     [rsi + (SavedSs - @Base)], edi\r
     DB      2eh                         ; cs:\r
-    mov     [rsi + (offset SavedEsp - offset @Base)], bx\r
+    mov     [rsi + (SavedEsp - @Base)], bx\r
     DB      66h, 2eh                    ; CS and operand size override\r
-    lidt    fword ptr [rsi + (offset _16Idtr - offset @Base)]\r
+    lidt    fword ptr [rsi + (_16Idtr - @Base)]\r
     DB      66h, 61h                    ; popad\r
     DB      1fh                         ; pop ds\r
     DB      07h                         ; pop es\r
@@ -202,22 +199,22 @@ InternalAsmThunk16  PROC    USES    rbp rbx rsi rdi
     mov     edi, (IA32_REGS ptr [rsi])._ESP\r
     lea     rdi, [edi - (sizeof (IA32_REGS) + 4)]\r
     imul    eax, r8d, 16                ; eax <- r8d(stack segment) * 16\r
-    mov     ebx, edi                    ; ebx <- stack offset for 16-bit code\r
+    mov     ebx, edi                    ; ebx <- stack for 16-bit code\r
     push    sizeof (IA32_REGS) / 4\r
     add     edi, eax                    ; edi <- linear address of 16-bit stack\r
     pop     rcx\r
     rep     movsd                       ; copy RegSet\r
-    lea     ecx, [rdx + (offset SavedCr4 - offset m16Start)]\r
+    lea     ecx, [rdx + (SavedCr4 - m16Start)]\r
     mov     eax, edx                    ; eax <- transition code address\r
     and     edx, 0fh\r
     shl     eax, 12\r
-    lea     edx, [rdx + (offset _BackFromUserCode - offset m16Start)]\r
+    lea     edx, [rdx + (_BackFromUserCode - m16Start)]\r
     mov     ax, dx\r
     stosd                               ; [edi] <- return address of user code\r
-    sgdt    fword ptr [rcx + (offset SavedGdt - offset SavedCr4)]\r
+    sgdt    fword ptr [rcx + (SavedGdt - SavedCr4)]\r
     sidt    fword ptr [rsp + 38h]       ; save IDT stack in argument space\r
     mov     rax, cr0\r
-    mov     [rcx + (offset SavedCr0 - offset SavedCr4)], eax\r
+    mov     [rcx + (SavedCr0 - SavedCr4)], eax\r
     and     eax, 7ffffffeh              ; clear PE, PG bits\r
     mov     rbp, cr4\r
     mov     [rcx], ebp                  ; save CR4 in SavedCr4\r
@@ -225,9 +222,9 @@ InternalAsmThunk16  PROC    USES    rbp rbx rsi rdi
     mov     esi, r8d                    ; esi <- 16-bit stack segment\r
     push    10h\r
     pop     rdx                         ; rdx <- selector for data segments\r
-    lgdt    fword ptr [rcx + (offset _16Gdtr - offset SavedCr4)]\r
+    lgdt    fword ptr [rcx + (_16Gdtr - SavedCr4)]\r
     pushfq\r
-    call    fword ptr [rcx + (offset _EntryPoint - offset SavedCr4)]\r
+    call    fword ptr [rcx + (_EntryPoint - SavedCr4)]\r
     popfq\r
     lidt    fword ptr [rsp + 38h]       ; restore protected mode IDTR\r
     lea     eax, [rbp - sizeof (IA32_REGS)]\r