Refine comments of X64 assembly files of MDE BaseLib.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@6277 6f19259b-4bc3-4df7-8a09-765794883524

15 files changed, 50 insertions, 59 deletions

diff --git a/MdePkg/Library/BaseLib/X64/CpuIdEx.S b/MdePkg/Library/BaseLib/X64/CpuIdEx.S
index 62d698a584..32abf114db 100644
--- a/MdePkg/Library/BaseLib/X64/CpuIdEx.S
+++ b/MdePkg/Library/BaseLib/X64/CpuIdEx.S
@@ -38,7 +38,7 @@ ASM_PFX(AsmCpuidEx):
     push    %rbx
     movl    %ecx,%eax
     movl    %edx,%ecx
-    push    %rax
+    push    %rax                  # save Index on stack
     cpuid
     mov     0x38(%rsp), %r10
     test    %r10, %r10
@@ -57,6 +57,6 @@ L3:
     jrcxz   L4
     mov     %edx, (%rcx)
 L4: 
-    pop     %rax
+    pop     %rax                  # restore Index to rax as return value
     pop     %rbx
     ret
diff --git a/MdePkg/Library/BaseLib/X64/DisablePaging64.S b/MdePkg/Library/BaseLib/X64/DisablePaging64.S
index 7a543febab..e4f77970ed 100644
--- a/MdePkg/Library/BaseLib/X64/DisablePaging64.S
+++ b/MdePkg/Library/BaseLib/X64/DisablePaging64.S
@@ -27,39 +27,39 @@
 # VOID
 # EFIAPI
 # InternalX86DisablePaging64 (
-#   IN      UINT16                    Cs,			%rdi
-#   IN      UINT64                    EntryPoint,		%rsi
-#   IN      UINT64                    Context1,  OPTIONAL	%rdx
-#   IN      UINT32                    Context2,  OPTIONAL	%rcx
-#   IN      UINT64                    NewStack			%r8
+#   IN      UINT16                    Cs,
+#   IN      UINT64                    EntryPoint,
+#   IN      UINT64                    Context1,  OPTIONAL
+#   IN      UINT32                    Context2,  OPTIONAL
+#   IN      UINT64                    NewStack
 #   );
 #------------------------------------------------------------------------------
 
 .global ASM_PFX(InternalX86DisablePaging64)
 ASM_PFX(InternalX86DisablePaging64):
     cli    
-    shl    $0x20,%rcx
+    shl    $0x20,%rcx                     # rcx[32..47] <- Cs
     lea    L1, %eax
     mov    %r8d, %esi 

-    or     %rax, %rcx

+    or     %rax, %rcx                     # rcx[0..47] <- Cs:@F

     mov    %r9d, %edi 

-    mov    0x28(%rsp), %eax

+    mov    0x28(%rsp), %eax               # eax <- New Stack

     push   %rcx

-    ret

+    ret                                   # switch to compatibility mode

 L1:
-    mov    %eax,%esp
+    mov    %eax,%esp                      # set up new stack
     mov    %cr0,%rax
     btr    $0x1f,%eax
-    mov    %rax,%cr0
+    mov    %rax,%cr0                      # disable paging
     mov    $0xc0000080,%ecx
     rdmsr  
-    and    $0xfe,%ah
+    and    $0xfe,%ah                      # clear LME
     wrmsr  
     mov    %cr4,%rax
-    and    $0xdf,%al
+    and    $0xdf,%al                      # clear PAE
     mov    %rax,%cr4
-    push   %rdi
-    push   %rsi
-    callq  *%rdx
-    jmp    .
+    push   %rdi                           # push Context2
+    push   %rsi                           # push Context1
+    callq  *%rdx                          # transfer control to EntryPoint
+    jmp    .                              # no one should get here
 
diff --git a/MdePkg/Library/BaseLib/X64/EnablePaging64.S b/MdePkg/Library/BaseLib/X64/EnablePaging64.S
index 452bd39acc..6a66aba3f7 100644
--- a/MdePkg/Library/BaseLib/X64/EnablePaging64.S
+++ b/MdePkg/Library/BaseLib/X64/EnablePaging64.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -26,36 +26,36 @@
 # VOID
 # EFIAPI
 # InternalX86EnablePaging64 (
-#   IN      UINT16                    Cs,			%rdi
-#   IN      UINT64                    EntryPoint,		%rsi
-#   IN      UINT64                    Context1,  OPTIONAL	%rdx
-#   IN      UINT64                    Context2,  OPTIONAL	%rcx
-#   IN      UINT64                    NewStack			%r8
+#   IN      UINT16                    Cs,
+#   IN      UINT64                    EntryPoint,
+#   IN      UINT64                    Context1,  OPTIONAL
+#   IN      UINT64                    Context2,  OPTIONAL
+#   IN      UINT64                    NewStack
 #   );
 #------------------------------------------------------------------------------
 .global ASM_PFX(InternalX86EnablePaging64)
 ASM_PFX(InternalX86EnablePaging64):
     cli    
-    pop    %rax
+    pop    %rax                      # skip the return address
     callq  Base
 Base:
-    addl   $(L1-Base),(%rsp)
+    addl   $(L1-Base),(%rsp)         # offset for ret, seg is the 1st arg
     mov    %cr4,%rax
     or     $0x20,%al
-    mov    %rax,%cr4
+    mov    %rax,%cr4                 # enable PAE
     mov    $0xc0000080,%ecx
     rdmsr  
-    or     $0x1,%ah
+    or     $0x1,%ah                  # set LME
     wrmsr  
     mov    %cr0,%rax
     bts    $0x1f,%eax
-    mov    %rax,%cr0
+    mov    %rax,%cr0                 # enable paging
     lret   
-L1:
+L1:                                  # long mode starts here
     addr32 mov (%esp),%rbx
     addr32 mov 0x8(%esp),%rcx
     addr32 mov 0x10(%esp),%rdx
     addr32 mov 0x18(%esp),%rsp
     add    $-0x20,%rsp
     callq  *%rbx
-    jmp    .
+    jmp    .                         # dead loop if EntryPoint() returned
diff --git a/MdePkg/Library/BaseLib/X64/EnablePaging64.asm b/MdePkg/Library/BaseLib/X64/EnablePaging64.asm
index c54843008a..bd5770d87c 100644
--- a/MdePkg/Library/BaseLib/X64/EnablePaging64.asm
+++ b/MdePkg/Library/BaseLib/X64/EnablePaging64.asm
@@ -1,6 +1,6 @@
 ;------------------------------------------------------------------------------

 ;

-; Copyright (c) 2006, Intel Corporation

+; Copyright (c) 2006 - 2008, Intel Corporation

 ; All rights reserved. This program and the accompanying materials

 ; are licensed and made available under the terms and conditions of the BSD License

 ; which accompanies this distribution.  The full text of the license may be found at

@@ -40,14 +40,14 @@ InternalX86EnablePaging64 PROC
     call    @Base

 @Base:

     add     dword ptr [rsp], @F - @Base ; offset for far retf, seg is the 1st arg

-    mov     rax, cr4                    ; mov eax, cr4

+    mov     rax, cr4

     or      al, (1 SHL 5)

     mov     cr4, rax                    ; enable PAE

     mov     ecx, 0c0000080h

     rdmsr

     or      ah, 1                       ; set LME

     wrmsr

-    mov     rax, cr0                    ; mov eax, cr0

+    mov     rax, cr0

     bts     eax, 31

     mov     cr0, rax                    ; enable paging

     retf

diff --git a/MdePkg/Library/BaseLib/X64/LongJump.S b/MdePkg/Library/BaseLib/X64/LongJump.S
index 69229c2bf1..c135d3bd06 100644
--- a/MdePkg/Library/BaseLib/X64/LongJump.S
+++ b/MdePkg/Library/BaseLib/X64/LongJump.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------

 #

-# Copyright (c) 2006, Intel Corporation

+# Copyright (c) 2006 -2008, Intel Corporation

 # All rights reserved. This program and the accompanying materials

 # are licensed and made available under the terms and conditions of the BSD License

 # which accompanies this distribution.  The full text of the license may be found at

@@ -38,5 +38,5 @@ ASM_PFX(InternalLongJump):
     mov     0x30(%rcx), %r13

     mov     0x38(%rcx), %r14

     mov     0x40(%rcx), %r15

-    mov     %rdx, %rax

+    mov     %rdx, %rax          # set return value

     jmp     *0x48(%rcx)

diff --git a/MdePkg/Library/BaseLib/X64/ReadMm0.S b/MdePkg/Library/BaseLib/X64/ReadMm0.S
index b14b061419..1a2de9f536 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm0.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm0.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm0)
 .align 16
 ASM_PFX(AsmReadMm0):
-    #DB      48h, 0fh, 7eh, 0c0h
     movd 	%mm0, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/ReadMm1.S b/MdePkg/Library/BaseLib/X64/ReadMm1.S
index 6af2b17039..a50e0c319c 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm1.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm1.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm1)
 .align 16
 ASM_PFX(AsmReadMm1):
-    #DB      48h, 0fh, 7eh, 0c8h
     movd	%mm1, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/ReadMm2.S b/MdePkg/Library/BaseLib/X64/ReadMm2.S
index d80ad64eec..88d829e904 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm2.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm2.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm2)
 .align 16
 ASM_PFX(AsmReadMm2):
-    #DB      48h, 0fh, 7eh, 0d0h
     movd	%mm2, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/ReadMm3.S b/MdePkg/Library/BaseLib/X64/ReadMm3.S
index 7885952ed6..4565741d2e 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm3.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm3.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm3)
 .align 16
 ASM_PFX(AsmReadMm3):
-    #DB      48h, 0fh, 7eh, 0d8h
     movd	%mm3, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/ReadMm4.S b/MdePkg/Library/BaseLib/X64/ReadMm4.S
index 8c9830cc97..491a876b3f 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm4.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm4.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm4)
 .align 16
 ASM_PFX(AsmReadMm4):
-    #DB      48h, 0fh, 7eh, 0e0h
     movd	%mm4, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/ReadMm5.S b/MdePkg/Library/BaseLib/X64/ReadMm5.S
index 19f0fa4c5e..ac2119d649 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm5.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm5.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm5)
 .align 16
 ASM_PFX(AsmReadMm5):
-    #DB      48h, 0fh, 7eh, 0e8h
     movd	%mm5, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/ReadMm6.S b/MdePkg/Library/BaseLib/X64/ReadMm6.S
index 49cf4f3626..1816c93301 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm6.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm6.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm6)
 .align 16
 ASM_PFX(AsmReadMm6):
-    #DB      48h, 0fh, 7eh, 0f0h
     movd	%mm6, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/ReadMm7.S b/MdePkg/Library/BaseLib/X64/ReadMm7.S
index 94abd776b4..c5465769c4 100644
--- a/MdePkg/Library/BaseLib/X64/ReadMm7.S
+++ b/MdePkg/Library/BaseLib/X64/ReadMm7.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -32,6 +32,5 @@
 .global ASM_PFX(AsmReadMm7)
 .align 16
 ASM_PFX(AsmReadMm7):
-    #DB      48h, 0fh, 7eh, 0f8h
     movd	%mm7, %rax
     ret
diff --git a/MdePkg/Library/BaseLib/X64/WriteDr5.asm b/MdePkg/Library/BaseLib/X64/WriteDr5.asm
index 86009c3287..e35f53e6dd 100644
--- a/MdePkg/Library/BaseLib/X64/WriteDr5.asm
+++ b/MdePkg/Library/BaseLib/X64/WriteDr5.asm
@@ -1,6 +1,6 @@
 ;------------------------------------------------------------------------------

 ;

-; Copyright (c) 2006, Intel Corporation

+; Copyright (c) 2006 - 2008, Intel Corporation

 ; All rights reserved. This program and the accompanying materials

 ; are licensed and made available under the terms and conditions of the BSD License

 ; which accompanies this distribution.  The full text of the license may be found at

@@ -26,7 +26,7 @@
 ;------------------------------------------------------------------------------

 ; UINTN

 ; EFIAPI

-; AsmWriteDr6 (

+; AsmWriteDr5 (

 ;   IN UINTN Value

 ;   );

 ;------------------------------------------------------------------------------

diff --git a/MdePkg/Library/BaseLib/X64/WriteMsr64.S b/MdePkg/Library/BaseLib/X64/WriteMsr64.S
index 2b0a557128..4a06f85e8a 100644
--- a/MdePkg/Library/BaseLib/X64/WriteMsr64.S
+++ b/MdePkg/Library/BaseLib/X64/WriteMsr64.S
@@ -1,6 +1,6 @@
 #------------------------------------------------------------------------------
 #
-# Copyright (c) 2006, Intel Corporation
+# Copyright (c) 2006 - 2008, Intel Corporation
 # All rights reserved. This program and the accompanying materials
 # are licensed and made available under the terms and conditions of the BSD License
 # which accompanies this distribution.  The full text of the license may be found at
@@ -29,12 +29,11 @@
 #   IN UINT32  Index,
 #   IN UINT64  Value
 #   );
-# TODO:
 #------------------------------------------------------------------------------
 .global ASM_PFX(AsmWriteMsr64)
 .align 16
 ASM_PFX(AsmWriteMsr64):
-    mov	%rdx, %rax
-    shr $0x20, %rdx
+    mov	%rdx, %rax            # meanwhile, rax <- return value
+    shr $0x20, %rdx           # edx:eax contains the value to write
     wrmsr
     ret