Add ArmPlatformPkg from ARM Ltd. patch.

[mirror_edk2.git] / ArmPlatformPkg / ArmRealViewEbPkg / Library / ArmRealViewEbLibRTSM / ArmRealViewEbHelper.asm

diff --git a/ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm b/ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm
new file mode 100644 (file)
index 0000000..c0b4263
--- /dev/null
+++ b/ArmPlatformPkg/ArmRealViewEbPkg/Library/ArmRealViewEbLibRTSM/ArmRealViewEbHelper.asm
@@ -0,0 +1,63 @@
+//\r
+//  Copyright (c) 2011, ARM Limited. All rights reserved.\r
+//  \r
+//  This program and the accompanying materials                          \r
+//  are licensed and made available under the terms and conditions of the BSD License         \r
+//  which accompanies this distribution.  The full text of the license may be found at        \r
+//  http://opensource.org/licenses/bsd-license.php                                            \r
+//\r
+//  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
+//  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             \r
+//\r
+//\r
+\r
+#include <AsmMacroIoLib.h>\r
+#include <Base.h>\r
+#include <Library/PcdLib.h>\r
+#include <ArmPlatform.h>\r
+#include <AutoGen.h>\r
+\r
+  INCLUDE AsmMacroIoLib.inc\r
+  \r
+  EXPORT  ArmPlatformIsMemoryInitialized\r
+  EXPORT  ArmPlatformInitializeBootMemory\r
+  \r
+  PRESERVE8\r
+  AREA    ArmRealViewEbHelper, CODE, READONLY\r
+\r
+/**\r
+  Called at the early stage of the Boot phase to know if the memory has already been initialized\r
+\r
+  Running the code from the reset vector does not mean we start from cold boot. In some case, we\r
+  can go through this code with the memory already initialized.\r
+  Because this function is called at the early stage, the implementation must not use the stack.\r
+  Its implementation must probably done in assembly to ensure this requirement.\r
+\r
+  @return   Return the condition value into the 'Z' flag\r
+\r
+**/\r
+ArmPlatformIsMemoryInitialized\r
+  // Check if the memory has been already mapped, if so skipped the memory initialization\r
+  LoadConstantToReg (ARM_EB_SYSCTRL, r0)\r
+  ldr   r0, [r0, #0]\r
+  \r
+  // 0x200 (BIT9): This read-only bit returns the remap status.\r
+  and   r0, r0, #0x200\r
+  tst   r0, #0x200\r
+  bx   lr\r
+    \r
+/**\r
+  Initialize the memory where the initial stacks will reside\r
+\r
+  This memory can contain the initial stacks (Secure and Secure Monitor stacks).\r
+  In some platform, this region is already initialized and the implementation of this function can\r
+  do nothing. This memory can also represent the Secure RAM.\r
+  This function is called before the satck has been set up. Its implementation must ensure the stack\r
+  pointer is not used (probably required to use assembly language)\r
+\r
+**/\r
+ArmPlatformInitializeBootMemory\r
+  // The SMC does not need to be initialized for RTSM\r
+  bx    lr\r
+  \r
+  END\r