audk/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibCTA9x4/CTA9x4Helper.asm

69 lines
2.5 KiB
NASM

//
// 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
IMPORT InitializeSMC
PRESERVE8
AREA CTA9x4Helper, 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_VE_SYS_CFGRW1_REG ,r0)
ldr r0, [r0, #0]
// 0x40000000 = Value of Physical Configuration Switch SW[0]
and r0, r0, #0x40000000
tst r0, #0x40000000
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
mov r5, lr
// Initialize PL354 SMC
LoadConstantToReg (ARM_VE_SMC_CTRL_BASE, r1)
LoadConstantToReg (ARM_VE_SMB_PERIPH_VRAM, r2)
blx InitializeSMC
bx r5
END