diff options
Diffstat (limited to 'UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionHandlerAsm.asm')
-rw-r--r-- | UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionHandlerAsm.asm | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionHandlerAsm.asm b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionHandlerAsm.asm index 3ff01b2a0c..12bbec0690 100644 --- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionHandlerAsm.asm +++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionHandlerAsm.asm @@ -1,5 +1,5 @@ ;------------------------------------------------------------------------------ ;
-; Copyright (c) 2012 - 2013, Intel Corporation. All rights reserved.<BR>
+; Copyright (c) 2012 - 2015, Intel Corporation. All rights reserved.<BR>
; 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
@@ -250,10 +250,22 @@ ErrorCodeAndVectorOnStack: push eax
;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
+ mov eax, 1
+ push ebx ; temporarily save value of ebx on stack
+ cpuid ; use CPUID to determine if FXSAVE/FXRESTOR and DE
+ ; are supported
+ pop ebx ; retore value of ebx that was overwritten by CPUID
mov eax, cr4
- or eax, 208h
+ push eax ; push cr4 firstly
+ test edx, BIT24 ; Test for FXSAVE/FXRESTOR support
+ jz @F
+ or eax, BIT9 ; Set CR4.OSFXSR
+@@:
+ test edx, BIT2 ; Test for Debugging Extensions support
+ jz @F
+ or eax, BIT3 ; Set CR4.DE
+@@:
mov cr4, eax
- push eax
mov eax, cr3
push eax
mov eax, cr2
@@ -280,7 +292,11 @@ ErrorCodeAndVectorOnStack: ;; FX_SAVE_STATE_IA32 FxSaveState;
sub esp, 512
mov edi, esp
+ test edx, BIT24 ; Test for FXSAVE/FXRESTOR support.
+ ; edx still contains result from CPUID above
+ jz @F
db 0fh, 0aeh, 07h ;fxsave [edi]
+@@:
;; UEFI calling convention for IA32 requires that Direction flag in EFLAGs is clear
cld
@@ -307,7 +323,13 @@ ErrorCodeAndVectorOnStack: ;; FX_SAVE_STATE_IA32 FxSaveState;
mov esi, esp
+ mov eax, 1
+ cpuid ; use CPUID to determine if FXSAVE/FXRESTOR
+ ; are supported
+ test edx, BIT24 ; Test for FXSAVE/FXRESTOR support
+ jz @F
db 0fh, 0aeh, 0eh ; fxrstor [esi]
+@@:
add esp, 512
;; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
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