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| author | Jeff Fan <jeff.fan@intel.com> | 2015-12-18 03:24:27 +0000 |
|---|---|---|
| committer | vanjeff <vanjeff@Edk2> | 2015-12-18 03:24:27 +0000 |
| commit | 4de216c01641fe4362cabfa0687378a973490832 (patch) | |
| tree | e24a5835c1a90514a2f678442c0a3c83777bd78c /UefiCpuPkg/CpuMpPei/CpuMpPei.c | |
| parent | 9d39ed931bf59b8d5afdccf7e1c30ece817b7a04 (diff) | |
| download | edk2-4de216c01641fe4362cabfa0687378a973490832.tar.gz edk2-4de216c01641fe4362cabfa0687378a973490832.tar.bz2 edk2-4de216c01641fe4362cabfa0687378a973490832.zip | |
UefiCpuPkg/CpuMpPei: Add GetApLoopMode() to get AP loop mode
Add GetApLoopMode() that will get PCD PcdCpuApLoopMode firstly. If it is
ApInMwaitLoop, we will check if MONITOR/MWAIT feature supported by CPUID. If
MONITOR/MWAIT feature is not supported, force AP loop mode to ApInHltLoop.
GetApLoopMode() also return the largest line size required.
Contributed-under: TianoCore Contribution Agreement 1.0
Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Signed-off-by: Michael Kinney <michael.d.kinney@intel.com>
Tested-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19343 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'UefiCpuPkg/CpuMpPei/CpuMpPei.c')
| -rw-r--r-- | UefiCpuPkg/CpuMpPei/CpuMpPei.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/UefiCpuPkg/CpuMpPei/CpuMpPei.c b/UefiCpuPkg/CpuMpPei/CpuMpPei.c index 2e6e7611a2..ac609a01f8 100644 --- a/UefiCpuPkg/CpuMpPei/CpuMpPei.c +++ b/UefiCpuPkg/CpuMpPei/CpuMpPei.c @@ -118,6 +118,54 @@ ApFuncEnableX2Apic ( }
/**
+ Get AP loop mode.
+
+ @param MonitorFilterSize Returns the largest monitor-line size in bytes.
+
+ @return The AP loop mode.
+**/
+UINT8
+GetApLoopMode (
+ OUT UINT16 *MonitorFilterSize
+ )
+{
+ UINT8 ApLoopMode;
+ UINT32 RegEbx;
+ UINT32 RegEcx;
+ UINT32 RegEdx;
+
+ ASSERT (MonitorFilterSize != NULL);
+
+ ApLoopMode = PcdGet8 (PcdCpuApLoopMode);
+ ASSERT (ApLoopMode >= ApInHltLoop && ApLoopMode <= ApInRunLoop);
+ if (ApLoopMode == ApInMwaitLoop) {
+ AsmCpuid (CPUID_VERSION_INFO, NULL, NULL, &RegEcx, NULL);
+ if ((RegEcx & BIT3) == 0) {
+ //
+ // If processor does not support MONITOR/MWAIT feature
+ // by CPUID.[EAX=01H]:ECX.BIT3, force AP in Hlt-loop mode
+ //
+ ApLoopMode = ApInHltLoop;
+ }
+ }
+
+ if (ApLoopMode == ApInHltLoop) {
+ *MonitorFilterSize = 0;
+ } else if (ApLoopMode == ApInRunLoop) {
+ *MonitorFilterSize = sizeof (UINT32);
+ } else if (ApLoopMode == ApInMwaitLoop) {
+ //
+ // CPUID.[EAX=05H]:EBX.BIT0-15: Largest monitor-line size in bytes
+ // CPUID.[EAX=05H].EDX: C-states supported using MWAIT
+ //
+ AsmCpuid (CPUID_MONITOR_MWAIT, NULL, &RegEbx, NULL, &RegEdx);
+ *MonitorFilterSize = RegEbx & 0xFFFF;
+ }
+
+ return ApLoopMode;
+}
+
+/**
Get CPU MP Data pointer from the Guided HOB.
@return Pointer to Pointer to PEI CPU MP Data
|