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| author | Olivier Martin <Olivier.Martin@arm.com> | 2015-07-06 16:56:31 +0000 |
|---|---|---|
| committer | oliviermartin <oliviermartin@Edk2> | 2015-07-06 16:56:31 +0000 |
| commit | 5dbacdb21b59748e885c2eccae370b81271ab795 (patch) | |
| tree | 69f477c94ae7e754ab9214a222134e9d07c4ae89 /ArmPlatformPkg/PrePi/AArch64 | |
| parent | 40a3f38f67cee7046feb5a5666883cc75a6962ff (diff) | |
| download | edk2-5dbacdb21b59748e885c2eccae370b81271ab795.tar.gz | |
ArmPlatformPkg/PrePi: Make dynamic the top of the System Memory
This change allows to change the top of the System Memory that
was hardcoded by:
FixedPcdGet64 (PcdSystemMemoryBase) + FixedPcdGet64 (PcdSystemMemorySize)
It allows to add support when the Trusted Firmware reserves the
top of the System Memory as Trusted. The size of this region
might not be known in advance.
Note: The reason why the start of the System Memory has not been
made dynamic is because the early code calculates where to place
the stack from the top of the System Memory.
So there is no need to make the start of the System Memory a
dynamic value at the early stage of the boot phase.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <Olivier.Martin@arm.com>
Reviewed-by: Ronald Cron <Ronald.Cron@arm.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17835 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'ArmPlatformPkg/PrePi/AArch64')
| -rw-r--r-- | ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S b/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S index fcea9496c..2c4a7e532 100644 --- a/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S +++ b/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S @@ -1,5 +1,5 @@ //
-// Copyright (c) 2011-2013, ARM Limited. All rights reserved.
+// Copyright (c) 2011-2015, 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
@@ -24,8 +24,10 @@ GCC_ASM_IMPORT(ArmReadMpidr) GCC_ASM_IMPORT(ArmPlatformPeiBootAction)
GCC_ASM_IMPORT(ArmPlatformStackSet)
GCC_ASM_EXPORT(_ModuleEntryPoint)
+GCC_ASM_EXPORT(mSystemMemoryEnd)
-StartupAddr: .8byte ASM_PFX(CEntryPoint)
+StartupAddr: .8byte ASM_PFX(CEntryPoint)
+mSystemMemoryEnd: .8byte 0
ASM_PFX(_ModuleEntryPoint):
// Do early platform specific actions
@@ -40,12 +42,23 @@ _SetSVCMode: // Check if we can install the stack at the top of the System Memory or if we need
// to install the stacks at the bottom of the Firmware Device (case the FD is located
// at the top of the DRAM)
-_SetupStackPosition:
- // Compute Top of System Memory
- LoadConstantToReg (FixedPcdGet64 (PcdSystemMemoryBase), x1)
- LoadConstantToReg (FixedPcdGet64 (PcdSystemMemorySize), x2)
+_SystemMemoryEndInit:
+ ldr x1, mSystemMemoryEnd
+
+ // Is mSystemMemoryEnd initialized?
+ cmp x1, #0
+ bne _SetupStackPosition
+
+ LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryBase), x1)
+ LoadConstantToReg (FixedPcdGet32(PcdSystemMemorySize), x2)
sub x2, x2, #1
- add x1, x1, x2 // x1 = SystemMemoryTop = PcdSystemMemoryBase + PcdSystemMemorySize
+ add x1, x1, x2
+ // Update the global variable
+ adr x2, mSystemMemoryEnd
+ str x1, [x2]
+
+_SetupStackPosition:
+ // r1 = SystemMemoryTop
// Calculate Top of the Firmware Device
LoadConstantToReg (FixedPcdGet32(PcdFdBaseAddress), x2)
|