Move SmmDebug feature from ASM to C.

SmmDebug feature is implemented in ASM, which is not easy to maintain.
So we move it to C function.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: "Yao, Jiewen" <jiewen.yao@intel.com>
Reviewed-by: "Kinney, Michael D" <michael.d.kinney@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18946 6f19259b-4bc3-4df7-8a09-765794883524

UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.S

@@ -24,7 +24,6 @@ ASM_GLOBAL  ASM_PFX(gcSmiHandlerSize)
 ASM_GLOBAL  ASM_PFX(gSmiCr3)
 ASM_GLOBAL  ASM_PFX(gSmiStack)
 ASM_GLOBAL  ASM_PFX(gSmbase)
-ASM_GLOBAL  ASM_PFX(FeaturePcdGet (PcdCpuSmmDebug))
 ASM_GLOBAL  ASM_PFX(FeaturePcdGet (PcdCpuSmmStackGuard))
 ASM_GLOBAL  ASM_PFX(gSmiHandlerIdtr)
 
@@ -148,43 +147,22 @@ L5:
 #   jmp     _SmiHandler                 # instruction is not needed
 
 _SmiHandler:
-    cmpb    $0, ASM_PFX(FeaturePcdGet (PcdCpuSmmDebug))
-    jz      L3
-
-L6:
-    call    L1
-L1:
-    popl    %ebp
-    movl    $0x80000001, %eax
-    cpuid
-    btl     $29, %edx                   # check cpuid to identify X64 or IA32
-    leal    (0x7fc8 - (L1 - _SmiEntryPoint))(%ebp), %edi
-    leal    4(%edi), %esi
-    jnc     L2
-    addl    $4, %esi
-L2:
-    movl    (%esi), %ecx
-    movl    (%edi), %edx
-L7:
-    movl    %ecx, %dr6
-    movl    %edx, %dr7                  # restore DR6 & DR7 before running C code
-L3:
-
-    pushl   (%esp)
+    movl    (%esp), %ebx
 
+    pushl   %ebx
+    movl    $ASM_PFX(CpuSmmDebugEntry), %eax
+    call    *%eax
+    popl    %ecx
+    
+    pushl   %ebx
     movl    $ASM_PFX(SmiRendezvous), %eax
     call    *%eax
     popl    %ecx
 
-
-    cmpb    $0, ASM_PFX(FeaturePcdGet (PcdCpuSmmDebug))
-    jz      L4
-
-    movl    %dr6, %ecx
-    movl    %dr7, %edx
-    movl    %ecx, (%esi)
-    movl    %edx, (%edi)
-L4:
+    pushl   %ebx
+    movl    $ASM_PFX(CpuSmmDebugExit), %eax
+    call    *%eax
+    popl    %ecx
 
     rsm
 

UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.asm

@@ -34,14 +34,15 @@ PROTECT_MODE_CS EQU   08h
 PROTECT_MODE_DS EQU   20h
 TSS_SEGMENT     EQU   40h
 
-SmiRendezvous   PROTO   C
+SmiRendezvous      PROTO   C
+CpuSmmDebugEntry   PROTO   C
+CpuSmmDebugExit    PROTO   C
 
 EXTERNDEF   gcSmiHandlerTemplate:BYTE
 EXTERNDEF   gcSmiHandlerSize:WORD
 EXTERNDEF   gSmiCr3:DWORD
 EXTERNDEF   gSmiStack:DWORD
 EXTERNDEF   gSmbase:DWORD
-EXTERNDEF   FeaturePcdGet (PcdCpuSmmDebug):BYTE
 EXTERNDEF   FeaturePcdGet (PcdCpuSmmStackGuard):BYTE
 EXTERNDEF   gSmiHandlerIdtr:FWORD
 
@@ -151,40 +152,23 @@ gSmiCr3     DD      ?
 ;   jmp     _SmiHandler                 ; instruction is not needed
 
 _SmiHandler PROC
-    cmp     FeaturePcdGet (PcdCpuSmmDebug), 0
-    jz      @3
-    call    @1
-@1:
-    pop     ebp
-    mov     eax, 80000001h
-    cpuid
-    bt      edx, 29                     ; check cpuid to identify X64 or IA32
-    lea     edi, [ebp - (@1 - _SmiEntryPoint) + 7fc8h]
-    lea     esi, [edi + 4]
-    jnc     @2
-    add     esi, 4
-@2:
-    mov     ecx, [esi]
-    mov     edx, [edi]
-@5:
-    mov     dr6, ecx
-    mov     dr7, edx                    ; restore DR6 & DR7 before running C code
-@3:
-    mov     ecx, [esp]                  ; CPU Index
+    mov     ebx, [esp]                  ; CPU Index
 
-    push    ecx
-    mov     eax, SmiRendezvous
+    push    ebx
+    mov     eax, CpuSmmDebugEntry
     call    eax
     pop     ecx
 
-    cmp     FeaturePcdGet (PcdCpuSmmDebug), 0
-    jz      @4
+    push    ebx
+    mov     eax, SmiRendezvous
+    call    eax
+    pop     ecx
+    
+    push    ebx
+    mov     eax, CpuSmmDebugExit
+    call    eax
+    pop     ecx
 
-    mov     ecx, dr6
-    mov     edx, dr7
-    mov     [esi], ecx
-    mov     [edi], edx
-@4:
     rsm
 _SmiHandler ENDP