MdePkg/DebugAgent: Support IA32 processors without MSR_IA32_APIC_BASE_ADDRESS

Avoid use of Local APIC Base Address MSR (MSR_IA32_APIC_BASE_ADDRESS) if there is only 1 CPU present.

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>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17218 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Michael Kinney 2015-04-27 19:49:25 +00:00 committed by mdkinney
parent e9cd66d085
commit d5203c10e8
1 changed files with 11 additions and 2 deletions

View File

@ -1,7 +1,7 @@
/** @file /** @file
Multi-Processor support functions implementation. Multi-Processor support functions implementation.
Copyright (c) 2010 - 2014, Intel Corporation. All rights reserved.<BR> Copyright (c) 2010 - 2015, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License 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 which accompanies this distribution. The full text of the license may be found at
@ -138,9 +138,18 @@ GetProcessorIndex (
**/ **/
BOOLEAN BOOLEAN
IsBsp ( IsBsp (
IN UINT32 ProcessorIndex IN UINT32 ProcessorIndex
) )
{ {
//
// If there are less than 2 CPUs detected, then the currently executing CPU
// must be the BSP. This avoids an access to an MSR that may not be supported
// on single core CPUs.
//
if (mDebugCpuData.CpuCount < 2) {
return TRUE;
}
if (AsmMsrBitFieldRead64 (MSR_IA32_APIC_BASE_ADDRESS, 8, 8) == 1) { if (AsmMsrBitFieldRead64 (MSR_IA32_APIC_BASE_ADDRESS, 8, 8) == 1) {
if (mDebugMpContext.BspIndex != ProcessorIndex) { if (mDebugMpContext.BspIndex != ProcessorIndex) {
AcquireMpSpinLock (&mDebugMpContext.MpContextSpinLock); AcquireMpSpinLock (&mDebugMpContext.MpContextSpinLock);