[PATCH v2 0/2] Enable X2APIC after MP service is ready

[PATCH v2 0/2] Enable X2APIC after MP service is ready

[Jeff Fan]

https://bugzilla.tianocore.org/show_bug.cgi?id=575

v2:
  Updated #1 comments.

Jeff Fan (2):
  UefiCpuPkg/CpuCommonFeaturesLib: Support X2APIC enable
  UefiCpuPkg/MpInitLib: Check APIC mode change around AP function

 .../CpuCommonFeaturesLib/CpuCommonFeatures.h       | 15 +++++
 .../CpuCommonFeaturesLib/CpuCommonFeaturesLib.c    |  2 +-
 UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c   | 77 +++++++++++++++++++---
 UefiCpuPkg/Library/MpInitLib/MpLib.c               | 24 +++++--
 4 files changed, 102 insertions(+), 16 deletions(-)

-- 
2.9.3.windows.2

[PATCH v2 1/2] UefiCpuPkg/CpuCommonFeaturesLib: Support X2APIC enable

[Jeff Fan]

Current X2APIC is enabled in MpInitLib (used by CpuMpPei and CpuDxe) to follow
SDM suggestion. That means we only enable X2APIC if we found there are any
initial CPU ID value >= 255.

This patch is to provide one chance for platform to enable X2APIC even there is
no any initial CPU ID value >= 255.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
---
 .../CpuCommonFeaturesLib/CpuCommonFeatures.h       | 15 +++++
 .../CpuCommonFeaturesLib/CpuCommonFeaturesLib.c    |  2 +-
 UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c   | 77 +++++++++++++++++++---
 3 files changed, 83 insertions(+), 11 deletions(-)

diff --git a/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeatures.h b/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeatures.h
index aa6d112..9a7afed 100644
--- a/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeatures.h
+++ b/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeatures.h
@@ -798,6 +798,21 @@ C1eInitialize (
   );
 
 /**
+  Prepares for the data used by CPU feature detection and initialization.
+
+  @param[in]  NumberOfProcessors  The number of CPUs in the platform.
+
+  @return  Pointer to a buffer of CPU related configuration data.
+
+  @note This service could be called by BSP only.
+**/
+VOID *
+EFIAPI
+X2ApicGetConfigData (
+  IN UINTN  NumberOfProcessors
+  );
+
+/**
   Detects if X2Apci feature supported on current processor.
 
   Detect if X2Apci has been already enabled.
diff --git a/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeaturesLib.c b/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeaturesLib.c
index 3390aa8..793a095 100644
--- a/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeaturesLib.c
+++ b/UefiCpuPkg/Library/CpuCommonFeaturesLib/CpuCommonFeaturesLib.c
@@ -211,7 +211,7 @@ CpuCommonFeaturesLibConstructor (
   if (IsCpuFeatureSupported (CPU_FEATURE_X2APIC)) {
     Status = RegisterCpuFeature (
                "X2Apic",
-               NULL,
+               X2ApicGetConfigData,
                X2ApicSupport,
                X2ApicInitialize,
                CPU_FEATURE_X2APIC,
diff --git a/UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c b/UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c
index 9c2ad9a..6673c95 100644
--- a/UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c
+++ b/UefiCpuPkg/Library/CpuCommonFeaturesLib/X2Apic.c
@@ -15,6 +15,28 @@
 #include "CpuCommonFeatures.h"
 
 /**
+  Prepares for the data used by CPU feature detection and initialization.
+
+  @param[in]  NumberOfProcessors  The number of CPUs in the platform.
+
+  @return  Pointer to a buffer of CPU related configuration data.
+
+  @note This service could be called by BSP only.
+**/
+VOID *
+EFIAPI
+X2ApicGetConfigData (
+  IN UINTN  NumberOfProcessors
+  )
+{
+  BOOLEAN                            *ConfigData;
+
+  ConfigData = AllocateZeroPool (sizeof (BOOLEAN) * NumberOfProcessors);
+  ASSERT (ConfigData != NULL);
+  return ConfigData;
+}
+
+/**
   Detects if X2Apci feature supported on current processor.
 
   Detect if X2Apci has been already enabled.
@@ -39,8 +61,17 @@ X2ApicSupport (
   IN REGISTER_CPU_FEATURE_INFORMATION  *CpuInfo,
   IN VOID                              *ConfigData  OPTIONAL
   )
-{
-  return (GetApicMode () == LOCAL_APIC_MODE_X2APIC);
+{  
+  BOOLEAN                            *X2ApicEnabled;
+
+  ASSERT (ConfigData != NULL);
+  X2ApicEnabled = (BOOLEAN *) ConfigData;
+  //
+  // *ConfigData indicates if X2APIC enabled on current processor
+  //
+  X2ApicEnabled[ProcessorNumber] = (GetApicMode () == LOCAL_APIC_MODE_X2APIC) ? TRUE : FALSE;
+
+  return (CpuInfo->CpuIdVersionInfoEcx.Bits.x2APIC == 1);
 }
 
 /**
@@ -69,13 +100,39 @@ X2ApicInitialize (
   IN BOOLEAN                           State
   )
 {
-  PRE_SMM_CPU_REGISTER_TABLE_WRITE_FIELD (
-    ProcessorNumber,
-    Msr,
-    MSR_IA32_APIC_BASE,
-    MSR_IA32_APIC_BASE_REGISTER,
-    Bits.EXTD,
-    (State) ? 1 : 0
-    );
+  BOOLEAN                            *X2ApicEnabled;
+
+  ASSERT (ConfigData != NULL);
+  X2ApicEnabled = (BOOLEAN *) ConfigData;
+  if (X2ApicEnabled[ProcessorNumber]) {
+    if (!State) {
+      DEBUG ((DEBUG_ERROR, "X2APIC should be enabled by PcdCpuFeaturesUserConfiguration!\n"));
+      ASSERT (FALSE);
+    } else {
+      PRE_SMM_CPU_REGISTER_TABLE_WRITE_FIELD (
+        ProcessorNumber,
+        Msr,
+        MSR_IA32_APIC_BASE,
+        MSR_IA32_APIC_BASE_REGISTER,
+        Bits.EXTD,
+        1
+        );
+    }
+  } else {
+    //
+    // Enable X2APIC mode only if X2APIC is not enabled,
+    // Needn't to disabe X2APIC mode again if X2APIC is not enabled
+    //
+    if (State) {
+      CPU_REGISTER_TABLE_WRITE_FIELD (
+        ProcessorNumber,
+        Msr,
+        MSR_IA32_APIC_BASE,
+        MSR_IA32_APIC_BASE_REGISTER,
+        Bits.EXTD,
+        1
+        );
+    }
+  }
   return RETURN_SUCCESS;
 }
-- 
2.9.3.windows.2

[PATCH v2 2/2] UefiCpuPkg/MpInitLib: Check APIC mode change around AP function

[Jeff Fan]

If APIC ID values are changed during AP functions execution, we need to update
new APIC ID values in local data structure accordingly.

But if APIC mode change happened during AP function execution, we do not support
APIC ID value changed.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
---
 UefiCpuPkg/Library/MpInitLib/MpLib.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c
index 735e099..c6f8191 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c
@@ -547,6 +547,7 @@ ApWakeupFunction (
   volatile UINT32            *ApStartupSignalBuffer;
   CPU_INFO_IN_HOB            *CpuInfoInHob;
   UINT64                     ApTopOfStack;
+  UINTN                      CurrentApicMode;
 
   //
   // AP finished assembly code and begin to execute C code
@@ -560,6 +561,7 @@ ApWakeupFunction (
   ProgramVirtualWireMode ();
   SyncLocalApicTimerSetting (CpuMpData);
 
+  CurrentApicMode = GetApicMode ();
   while (TRUE) {
     if (CpuMpData->InitFlag == ApInitConfig) {
       //
@@ -627,11 +629,23 @@ ApWakeupFunction (
             ApStartupSignalBuffer = CpuMpData->CpuData[ProcessorNumber].StartupApSignal;
             CpuInfoInHob[ProcessorNumber].ApTopOfStack = CpuInfoInHob[CpuMpData->NewBspNumber].ApTopOfStack;
           } else {
-            //
-            // Re-get the CPU APICID and Initial APICID
-            //
-            CpuInfoInHob[ProcessorNumber].ApicId        = GetApicId ();
-            CpuInfoInHob[ProcessorNumber].InitialApicId = GetInitialApicId ();
+            if (CpuInfoInHob[ProcessorNumber].ApicId != GetApicId () ||
+                CpuInfoInHob[ProcessorNumber].InitialApicId != GetInitialApicId ()) {
+              if (CurrentApicMode != GetApicMode ()) {
+                //
+                // If APIC mode change happened during AP function execution,
+                // we do not support APIC ID value changed.
+                //
+                ASSERT (FALSE);
+                CpuDeadLoop ();
+              } else {
+                //
+                // Re-get the CPU APICID and Initial APICID if they are changed
+                //
+                CpuInfoInHob[ProcessorNumber].ApicId        = GetApicId ();
+                CpuInfoInHob[ProcessorNumber].InitialApicId = GetInitialApicId ();
+              }
+            }
           }
         }
         SetApState (&CpuMpData->CpuData[ProcessorNumber], CpuStateFinished);
-- 
2.9.3.windows.2