UefiCpuPkg/MpInitLib: Implementation of MpInitLibEnableDisableAP()

[mirror_edk2.git] / UefiCpuPkg / Library / MpInitLib / DxeMpLib.c

diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
index 762d76dd7a7f2d774dc004acd1f8bc1ab20ce511..988920fc0701449892c6a24c85981cae83d650e0 100644 (file)
--- a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
@@ -389,7 +389,31 @@ MpInitLibSwitchBSP (
   IN BOOLEAN                   EnableOldBSP\r
   )\r
 {\r
-  return EFI_UNSUPPORTED;\r
+  EFI_STATUS            Status;\r
+  BOOLEAN               OldInterruptState;\r
+\r
+  //\r
+  // Before send both BSP and AP to a procedure to exchange their roles,\r
+  // interrupt must be disabled. This is because during the exchange role\r
+  // process, 2 CPU may use 1 stack. If interrupt happens, the stack will\r
+  // be corrupted, since interrupt return address will be pushed to stack\r
+  // by hardware.\r
+  //\r
+  OldInterruptState = SaveAndDisableInterrupts ();\r
+\r
+  //\r
+  // Mask LINT0 & LINT1 for the old BSP\r
+  //\r
+  DisableLvtInterrupts ();\r
+\r
+  Status = SwitchBSPWorker (ProcessorNumber, EnableOldBSP);\r
+\r
+  //\r
+  // Restore interrupt state.\r
+  //\r
+  SetInterruptState (OldInterruptState);\r
+\r
+  return Status;\r
 }\r
 \r
 /**\r
@@ -430,5 +454,23 @@ MpInitLibEnableDisableAP (
   IN  UINT32                    *HealthFlag OPTIONAL\r
   )\r
 {\r
-  return EFI_UNSUPPORTED;\r
+  EFI_STATUS     Status;\r
+  BOOLEAN        TempStopCheckState;\r
+\r
+  TempStopCheckState = FALSE;\r
+  //\r
+  // temporarily stop checkAllAPsStatus for initialize parameters.\r
+  //\r
+  if (!mStopCheckAllApsStatus) {\r
+    mStopCheckAllApsStatus = TRUE;\r
+    TempStopCheckState     = TRUE;\r
+  }\r
+\r
+  Status = EnableDisableApWorker (ProcessorNumber, EnableAP, HealthFlag);\r
+\r
+  if (TempStopCheckState) {\r
+    mStopCheckAllApsStatus = FALSE;\r
+  }\r
+\r
+  return Status;\r
 }\r