diff options
Diffstat (limited to 'ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm')
-rw-r--r-- | ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm b/ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm new file mode 100644 index 0000000000..c0b4263a35 --- /dev/null +++ b/ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm @@ -0,0 +1,63 @@ +//
+// 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.
+//
+//
+
+#include <AsmMacroIoLib.h>
+#include <Base.h>
+#include <Library/PcdLib.h>
+#include <ArmPlatform.h>
+#include <AutoGen.h>
+
+ INCLUDE AsmMacroIoLib.inc
+
+ EXPORT ArmPlatformIsMemoryInitialized
+ EXPORT ArmPlatformInitializeBootMemory
+
+ PRESERVE8
+ AREA ArmRealViewEbHelper, CODE, READONLY
+
+/**
+ Called at the early stage of the Boot phase to know if the memory has already been initialized
+
+ Running the code from the reset vector does not mean we start from cold boot. In some case, we
+ can go through this code with the memory already initialized.
+ Because this function is called at the early stage, the implementation must not use the stack.
+ Its implementation must probably done in assembly to ensure this requirement.
+
+ @return Return the condition value into the 'Z' flag
+
+**/
+ArmPlatformIsMemoryInitialized
+ // Check if the memory has been already mapped, if so skipped the memory initialization
+ LoadConstantToReg (ARM_EB_SYSCTRL, r0)
+ ldr r0, [r0, #0]
+
+ // 0x200 (BIT9): This read-only bit returns the remap status.
+ and r0, r0, #0x200
+ tst r0, #0x200
+ bx lr
+
+/**
+ Initialize the memory where the initial stacks will reside
+
+ This memory can contain the initial stacks (Secure and Secure Monitor stacks).
+ In some platform, this region is already initialized and the implementation of this function can
+ do nothing. This memory can also represent the Secure RAM.
+ This function is called before the satck has been set up. Its implementation must ensure the stack
+ pointer is not used (probably required to use assembly language)
+
+**/
+ArmPlatformInitializeBootMemory
+ // The SMC does not need to be initialized for RTSM
+ bx lr
+
+ END
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