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UefiCpuPkg/CpuExceptionHandlerLib: Support IA32 processors without DE or FXSAVE/FXRESTOR

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Use CPUID Leaf 01 to detect support for debug extensions and FXSAVE/FXRESTOR instructions.
Do not enable those features in CR4 if they are not supported.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>





git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17221 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Michael Kinney
2015-04-27 19:54:52 +00:00
committed by mdkinney
parent 5f72e68c90
commit 087c67d0a0
5 changed files with 59 additions and 12 deletions
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31
UefiCpuPkg/Library/CpuExceptionHandlerLib/Ia32/ExceptionHandlerAsm.S
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@@ -1,6 +1,6 @@
#------------------------------------------------------------------------------
#*
#* 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
@@ -447,10 +447,25 @@ ErrorCodeAndVectorOnStack:
pushl %eax
#; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
## insure FXSAVE/FXRSTOR is enabled in CR4...
## ... while we're at it, make sure DE is also enabled...
mov $1, %eax
pushl %ebx # temporarily save value of ebx on stack
cpuid # use CPUID to determine if FXSAVE/FXRESTOR
# and DE are supported
popl %ebx # retore value of ebx that was overwritten
# by CPUID
movl %cr4, %eax
orl $0x208, %eax
pushl %eax # push cr4 firstly
testl $BIT24, %edx # Test for FXSAVE/FXRESTOR support
jz L1
orl $BIT9, %eax # Set CR4.OSFXSR
L1:
testl $BIT2, %edx # Test for Debugging Extensions support
jz L2
orl $BIT3, %eax # Set CR4.DE
L2:
movl %eax, %cr4
pushl %eax
movl %cr3, %eax
pushl %eax
movl %cr2, %eax
@@ -477,7 +492,11 @@ ErrorCodeAndVectorOnStack:
#; FX_SAVE_STATE_IA32 FxSaveState;
subl $512, %esp
movl %esp, %edi
testl $BIT24, %edx # Test for FXSAVE/FXRESTOR support.
# edx still contains result from CPUID above
jz L3
.byte 0x0f, 0x0ae, 0x07 #fxsave [edi]
L3:
#; UEFI calling convention for IA32 requires that Direction flag in EFLAGs is clear
cld
@@ -503,7 +522,13 @@ ErrorCodeAndVectorOnStack:
#; FX_SAVE_STATE_IA32 FxSaveState;
movl %esp, %esi
movl $1, %eax
cpuid # use CPUID to determine if FXSAVE/FXRESTOR
# are supported
testl $BIT24, %edx # Test for FXSAVE/FXRESTOR support
jz L4
.byte 0x0f, 0x0ae, 0x0e # fxrstor [esi]
L4:
addl $512, %esp
#; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;