From e1808603dc4207ec82da1ffee3b23889b3cfc6e6 Mon Sep 17 00:00:00 2001
From: oliviermartin <oliviermartin@6f19259b-4bc3-4df7-8a09-765794883524>
Date: Thu, 18 Aug 2011 11:23:28 +0000
Subject: [PATCH] ArmPlatformPkg/PrePiHobListPointerLib: Fixed pointer
 calculation

In the PrePi module, the global variables are located at the top of the stack.
At the opposite of the PeiCore where the global variables are located in the
middle of the stack. The top stack region is reserved for Temporary Memory.



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12167 6f19259b-4bc3-4df7-8a09-765794883524
---
 .../PrePiHobListPointer.c                     | 34 ++++++++-----------
 .../PrePiHobListPointerLib.inf                |  1 +
 2 files changed, 16 insertions(+), 19 deletions(-)

diff --git a/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointer.c b/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointer.c
index dfcc27edf5..a18a02a9bb 100755
--- a/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointer.c
+++ b/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointer.c
@@ -17,14 +17,6 @@
 #include <Library/DebugLib.h>
 #include <Library/PcdLib.h>
 
-//
-// Have to use build system to set the original value in case we are running
-// from FLASH and globals don't work. So if you do a GetHobList() and gHobList
-// and gHobList is NULL the PCD default values are used.
-//
-VOID *gHobList = NULL;
-
-
 /**
   Returns the pointer to the HOB list.
 
@@ -39,11 +31,10 @@ PrePeiGetHobList (
   VOID
   )
 {
-  if (gHobList == NULL) {
-    return (VOID *)*(UINTN*)(PcdGet32 (PcdCPUCoresNonSecStackBase) + (PcdGet32 (PcdCPUCoresNonSecStackSize) / 2) - PcdGet32 (PcdHobListPtrGlobalOffset));
-  } else {
-    return gHobList;
-  }
+  return (VOID *)*(UINTN*)(PcdGet32 (PcdCPUCoresNonSecStackBase) +
+                           PcdGet32 (PcdCPUCoresNonSecStackSize) -
+                           PcdGet32 (PcdPeiGlobalVariableSize) +
+                           PcdGet32 (PcdHobListPtrGlobalOffset));
 }
 
 
@@ -60,10 +51,15 @@ PrePeiSetHobList (
   IN  VOID      *HobList
   )
 {
-  gHobList = HobList;
-  
-  //
-  // If this code is running from ROM this could fail
-  //
-  return (gHobList == HobList) ? EFI_SUCCESS: EFI_UNSUPPORTED;
+  UINTN* HobListPtr;
+
+  HobListPtr = (UINTN*)(PcdGet32 (PcdCPUCoresNonSecStackBase) +
+                        PcdGet32 (PcdCPUCoresNonSecStackSize) -
+                        PcdGet32 (PcdPeiGlobalVariableSize) +
+                        PcdGet32 (PcdHobListPtrGlobalOffset));
+
+  *HobListPtr = (UINTN)HobList;
+
+  return EFI_SUCCESS;
 }
+
diff --git a/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointerLib.inf b/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointerLib.inf
index 5142f19a4e..c1fa999da5 100755
--- a/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointerLib.inf
+++ b/ArmPlatformPkg/Library/PrePiHobListPointerLib/PrePiHobListPointerLib.inf
@@ -34,4 +34,5 @@
   gArmPlatformTokenSpaceGuid.PcdHobListPtrGlobalOffset
   gArmPlatformTokenSpaceGuid.PcdCPUCoresNonSecStackBase
   gArmPlatformTokenSpaceGuid.PcdCPUCoresNonSecStackSize
+  gArmPlatformTokenSpaceGuid.PcdPeiGlobalVariableSize
   
\ No newline at end of file