From e9cd66d0859f63ec6aab2b1ac863fe72b65fe474 Mon Sep 17 00:00:00 2001
From: Michael Kinney <michael.d.kinney@intel.com>
Date: Mon, 27 Apr 2015 19:48:00 +0000
Subject: [PATCH 1/1] MdePkg/BaseXApicX2ApicLib: Support IA32 processors
 without MSR_IA32_APIC_BASE_ADDRESS

Use Family from CPUID 01 to detect support for the Local APIC Base Address MSR (MSR_IA32_APIC_BASE_ADDRESS).
If this MSR is not supported, then use Local APIC Base Address from the PCD PcdCpuLocalApicBaseAddress.

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@17217 6f19259b-4bc3-4df7-8a09-765794883524
---
 .../BaseXApicX2ApicLib/BaseXApicX2ApicLib.c   | 69 +++++++++++++++++--
 .../BaseXApicX2ApicLib/BaseXApicX2ApicLib.inf |  7 +-
 2 files changed, 67 insertions(+), 9 deletions(-)

diff --git a/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.c b/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.c
index bf318e06e4..8c6e8d7415 100644
--- a/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.c
+++ b/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.c
@@ -22,11 +22,39 @@
 #include <Library/LocalApicLib.h>
 #include <Library/IoLib.h>
 #include <Library/TimerLib.h>
+#include <Library/PcdLib.h>
 
 //
 // Library internal functions
 //
 
+/**
+  Determine if the CPU supports the Local APIC Base Address MSR.
+
+  @retval TRUE  The CPU supports the Local APIC Base Address MSR.
+  @retval FALSE The CPU does not support the Local APIC Base Address MSR.
+
+**/
+BOOLEAN
+LocalApicBaseAddressMsrSupported (
+  VOID
+  )
+{
+  UINT32  RegEax;
+  UINTN   FamilyId;
+  
+  AsmCpuid (1, &RegEax, NULL, NULL, NULL);
+  FamilyId = BitFieldRead32 (RegEax, 8, 11);
+  if (FamilyId == 0x04 || FamilyId == 0x05) {
+    //
+    // CPUs with a FamilyId of 0x04 or 0x05 do not support the 
+    // Local APIC Base Address MSR
+    //
+    return FALSE;
+  }
+  return TRUE;
+}
+
 /**
   Retrieve the base address of local APIC.
 
@@ -39,8 +67,16 @@ GetLocalApicBaseAddress (
   VOID
   )
 {
-  MSR_IA32_APIC_BASE ApicBaseMsr;
-  
+  MSR_IA32_APIC_BASE  ApicBaseMsr;
+
+  if (!LocalApicBaseAddressMsrSupported ()) {
+    //
+    // If CPU does not support Local APIC Base Address MSR, then retrieve
+    // Local APIC Base Address from PCD
+    //
+    return PcdGet32 (PcdCpuLocalApicBaseAddress);
+  }
+
   ApicBaseMsr.Uint64 = AsmReadMsr64 (MSR_IA32_APIC_BASE_ADDRESS);
   
   return (UINTN)(LShiftU64 ((UINT64) ApicBaseMsr.Bits.ApicBaseHigh, 32)) +
@@ -61,10 +97,17 @@ SetLocalApicBaseAddress (
   IN UINTN                BaseAddress
   )
 {
-  MSR_IA32_APIC_BASE ApicBaseMsr;
+  MSR_IA32_APIC_BASE  ApicBaseMsr;
 
   ASSERT ((BaseAddress & (SIZE_4KB - 1)) == 0);
 
+  if (!LocalApicBaseAddressMsrSupported ()) {
+    //
+    // Ignore set request of the CPU does not support APIC Base Address MSR
+    //
+    return;
+  }
+
   ApicBaseMsr.Uint64 = AsmReadMsr64 (MSR_IA32_APIC_BASE_ADDRESS);
 
   ApicBaseMsr.Bits.ApicBaseLow  = (UINT32) (BaseAddress >> 12);
@@ -257,7 +300,14 @@ GetApicMode (
   VOID
   )
 {
-  MSR_IA32_APIC_BASE ApicBaseMsr;
+  MSR_IA32_APIC_BASE  ApicBaseMsr;
+
+  if (!LocalApicBaseAddressMsrSupported ()) {
+    //
+    // If CPU does not support APIC Base Address MSR, then return XAPIC mode
+    //
+    return LOCAL_APIC_MODE_XAPIC;
+  }
 
   ApicBaseMsr.Uint64 = AsmReadMsr64 (MSR_IA32_APIC_BASE_ADDRESS);
   //
@@ -288,8 +338,15 @@ SetApicMode (
   IN UINTN  ApicMode
   )
 {
-  UINTN              CurrentMode;
-  MSR_IA32_APIC_BASE ApicBaseMsr;
+  UINTN               CurrentMode;
+  MSR_IA32_APIC_BASE  ApicBaseMsr;
+
+  if (!LocalApicBaseAddressMsrSupported ()) {
+    //
+    // Ignore set request if the CPU does not support APIC Base Address MSR
+    //
+    return;
+  }
 
   CurrentMode = GetApicMode ();
   if (CurrentMode == LOCAL_APIC_MODE_XAPIC) {
diff --git a/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.inf b/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.inf
index 1e0e98433d..53e186858f 100644
--- a/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.inf
+++ b/UefiCpuPkg/Library/BaseXApicX2ApicLib/BaseXApicX2ApicLib.inf
@@ -21,7 +21,7 @@
   MODULE_UNI_FILE                = BaseXApicX2ApicLib.uni
   FILE_GUID                      = 967B6E05-F10D-4c10-8BF7-365291CA143F
   MODULE_TYPE                    = BASE
-  VERSION_STRING                 = 1.0
+  VERSION_STRING                 = 1.1
   LIBRARY_CLASS                  = LocalApicLib 
 
 #
@@ -42,7 +42,8 @@
   DebugLib
   TimerLib
   IoLib
+  PcdLib
 
 [Pcd]
-  gUefiCpuPkgTokenSpaceGuid.PcdCpuInitIpiDelayInMicroSeconds   ## SOMETIMES_CONSUMES
-
+  gUefiCpuPkgTokenSpaceGuid.PcdCpuInitIpiDelayInMicroSeconds  ## SOMETIMES_CONSUMES
+  gUefiCpuPkgTokenSpaceGuid.PcdCpuLocalApicBaseAddress        ## SOMETIMES_CONSUMES
-- 
2.39.2