ArmPlatformPkg/PrePeiCore: Reserve some memory on the top of the stack for Global Variables in XIP code

The size of this memory is controlled by a PCD. The Global Variable in this regsion are defined by their offset.

This memory region can be use to store the PEI Services Table Pointer.
Update the PeiServicesTablePointerLib to use this region instead of PcdPeiServicePtrAddr.



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11803 6f19259b-4bc3-4df7-8a09-765794883524

4 files changed, 41 insertions, 20 deletions

diff --git a/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.S b/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.S
index 53c16ccb6f..ffa4a46da9 100644
--- a/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.S
+++ b/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.S
@@ -1,22 +1,21 @@
 //
 //  Copyright (c) 2011, ARM Limited. All rights reserved.
 //  
-# This program and the accompanying materials                          
-#  are licensed and made available under the terms and conditions of the BSD License         
-#  which accompanies this distribution.  The full text of the license may be found at        
-#  http:#opensource.org/licenses/bsd-license.php                                            
-#
-#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
-#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             
-#
-#
+//  This program and the accompanying materials                          
+//  are licensed and made available under the terms and conditions of the BSD License         
+//  which accompanies this distribution.  The full text of the license may be found at        
+//  http://opensource.org/licenses/bsd-license.php                                            
+//
+//  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
+//  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             
+//
+//
 
 #include <AsmMacroIoLib.h>
 #include <Base.h>
 #include <Library/PcdLib.h>
 #include <AutoGen.h>
 
-#start of the code section
 .text
 .align 3
 
@@ -45,9 +44,17 @@ _SetupStack:
   add     r3,r3,r2,LSR #1   @ r3 = stack_offset + (stack_size/2)   <-- the top half is for the heap
   mov     sp, r3
 
-  # lr points to area in reset vector block containing PEI core address. lr needs to
-  # be saved from the beginning as the _ModuleEntryPoint could call helper functions
-  # that will overwrite 'lr'
+  # Only allocate memory in top of the primary core stack
+  cmp   r0, #0
+  bne   _PrepareArguments
+
+_AllocateGlobalPeiVariables:
+  # Reserve top of the stack for Global PEI Variables (eg: PeiServicesTablePointer)
+  LoadConstantToReg (FixedPcdGet32(PcdPeiGlobalVariableSize), r1)
+  sub   sp, sp, r1
+
+_PrepareArguments:
+  # The PEI Core Entry Point has been computed by GenFV and stored in the second entry of the Reset Vector
   LoadConstantToReg (FixedPcdGet32(PcdNormalFdBaseAddress), r2)
   add   r2, r2, #4
   ldr   r1, [r2]
diff --git a/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.asm b/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.asm
index de5fac15f8..231c14e36b 100644
--- a/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.asm
+++ b/ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.asm
@@ -33,15 +33,25 @@ _ModuleEntryPoint
 

 _SetupStack

   // Setup Stack for the 4 CPU cores

-  LoadConstantToReg (FixedPcdGet32(PcdCPUCoresNonSecStackBase) ,r1)

-  LoadConstantToReg (FixedPcdGet32(PcdCPUCoresNonSecStackSize) ,r2)

+  LoadConstantToReg (FixedPcdGet32(PcdCPUCoresNonSecStackBase), r1)

+  LoadConstantToReg (FixedPcdGet32(PcdCPUCoresNonSecStackSize), r2)

   

-  mov     r3,r0         // r3 = core_id

-  mul     r3,r3,r2      // r3 = core_id * stack_size = offset from the stack base

-  add     r3,r3,r1      // r3 = stack_base + offset

-  add     r3,r3,r2,LSR #1   // r3 = stack_offset + (stack_size/2)   <-- the top half is for the heap

-  mov     sp, r3

+  mov   r3, r0              // r3 = core_id

+  mul   r3, r3, r2          // r3 = core_id * stack_size = offset from the stack base

+  add   r3, r3, r1          // r3 = stack_base + offset

+  add   r3, r3, r2, LSR #1  // r3 = stack_offset + (stack_size/2) <-- the top half is for the heap

+  mov   sp, r3

 

+  // Only allocate memory in top of the primary core stack

+  cmp   r0, #0

+  bne   _PrepareArguments

+

+_AllocateGlobalPeiVariables

+  // Reserve top of the stack for Global PEI Variables (eg: PeiServicesTablePointer)

+  LoadConstantToReg (FixedPcdGet32(PcdPeiGlobalVariableSize), r1)

+  sub   sp, sp, r1

+

+_PrepareArguments

   // The PEI Core Entry Point has been computed by GenFV and stored in the second entry of the Reset Vector

   LoadConstantToReg (FixedPcdGet32(PcdNormalFdBaseAddress), r2)

   add   r2, r2, #4

diff --git a/ArmPlatformPkg/PrePeiCore/PrePeiCoreMPCore.inf b/ArmPlatformPkg/PrePeiCore/PrePeiCoreMPCore.inf
index 385b407363..4ca81f5a40 100644
--- a/ArmPlatformPkg/PrePeiCore/PrePeiCoreMPCore.inf
+++ b/ArmPlatformPkg/PrePeiCore/PrePeiCoreMPCore.inf
@@ -59,5 +59,7 @@
   gArmPlatformTokenSpaceGuid.PcdCPUCoresNonSecStackBase

   gArmPlatformTokenSpaceGuid.PcdCPUCoresNonSecStackSize

   

+  gArmPlatformTokenSpaceGuid.PcdPeiGlobalVariableSize

+  

   gArmTokenSpaceGuid.PcdGicDistributorBase

   gArmTokenSpaceGuid.PcdGicInterruptInterfaceBase

diff --git a/ArmPlatformPkg/PrePeiCore/PrePeiCoreUniCore.inf b/ArmPlatformPkg/PrePeiCore/PrePeiCoreUniCore.inf
index 58b8e339ed..c14e7353c6 100644
--- a/ArmPlatformPkg/PrePeiCore/PrePeiCoreUniCore.inf
+++ b/ArmPlatformPkg/PrePeiCore/PrePeiCoreUniCore.inf
@@ -57,5 +57,7 @@
   gArmPlatformTokenSpaceGuid.PcdCPUCoresNonSecStackBase

   gArmPlatformTokenSpaceGuid.PcdCPUCoresNonSecStackSize

   

+  gArmPlatformTokenSpaceGuid.PcdPeiGlobalVariableSize

+  

   gArmTokenSpaceGuid.PcdGicDistributorBase

   gArmTokenSpaceGuid.PcdGicInterruptInterfaceBase