ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibCTA9x4/CTA9x4Helper.asm

   1 //
   2 //  Copyright (c) 2011, ARM Limited. All rights reserved.
   3 //
   4 //  This program and the accompanying materials
   5 //  are licensed and made available under the terms and conditions of the BSD License
   6 //  which accompanies this distribution.  The full text of the license may be found at
   7 //  http://opensource.org/licenses/bsd-license.php
   8 //
   9 //  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 //  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 //
  12 //
  13
  14 #include <AsmMacroIoLib.h>
  15 #include <Base.h>
  16 #include <Library/PcdLib.h>
  17 #include <ArmPlatform.h>
  18 #include <Drivers/PL354Smc.h>
  19 #include <AutoGen.h>
  20
  21   INCLUDE AsmMacroIoLib.inc
  22
  23   EXPORT  ArmPlatformIsMemoryInitialized
  24   EXPORT  ArmPlatformInitializeBootMemory
  25   IMPORT  SMCInitializeNOR
  26   IMPORT  SMCInitializeSRAM
  27   IMPORT  SMCInitializePeripherals
  28   IMPORT  SMCInitializeVRAM
  29
  30   PRESERVE8
  31   AREA    CTA9x4Helper, CODE, READONLY
  32
  33 /**
  34   Called at the early stage of the Boot phase to know if the memory has already been initialized
  35
  36   Running the code from the reset vector does not mean we start from cold boot. In some case, we
  37   can go through this code with the memory already initialized.
  38   Because this function is called at the early stage, the implementation must not use the stack.
  39   Its implementation must probably done in assembly to ensure this requirement.
  40
  41   @return   Return the condition value into the 'Z' flag
  42
  43 **/
  44 ArmPlatformIsMemoryInitialized
  45   // Check if the memory has been already mapped, if so skipped the memory initialization
  46   LoadConstantToReg (ARM_VE_SYS_CFGRW1_REG ,r0)
  47   ldr   r0, [r0, #0]
  48
  49   // 0x40000000 = Value of Physical Configuration Switch SW[0]
  50   and   r0, r0, #0x40000000
  51   tst   r0, #0x40000000
  52   bx    lr
  53
  54 /**
  55   Initialize the memory where the initial stacks will reside
  56
  57   This memory can contain the initial stacks (Secure and Secure Monitor stacks).
  58   In some platform, this region is already initialized and the implementation of this function can
  59   do nothing. This memory can also represent the Secure RAM.
  60   This function is called before the satck has been set up. Its implementation must ensure the stack
  61   pointer is not used (probably required to use assembly language)
  62
  63 **/
  64 ArmPlatformInitializeBootMemory
  65   mov   r5, lr
  66
  67   //
  68   // Initialize PL354 SMC
  69   //
  70   LoadConstantToReg (ARM_VE_SMC_CTRL_BASE, r1)
  71
  72   // NOR Flash 0
  73   mov   r2, PL354_SMC_DIRECT_CMD_ADDR_CS(0,0)
  74   blx   SMCInitializeNOR
  75
  76   // NOR Flash 1
  77   mov   r2, PL354_SMC_DIRECT_CMD_ADDR_CS(1,0)
  78   blx   SMCInitializeNOR
  79
  80   // Setup SRAM
  81   blx   SMCInitializeSRAM
  82
  83   // Memory Mapped Peripherals
  84   blx   SMCInitializePeripherals
  85
  86   // Initialize VRAM
  87   //TODO: Check if we really must inititialize Video SRAM in UEFI. Does Linux can do it ? Does the Video driver can do it ?
  88   //      It will be faster (only initialize if required) and easier (remove assembly code because of a stack available) to move this initialization.
  89   LoadConstantToReg (VRAM_MOTHERBOARD_BASE, r2)
  90   blx   SMCInitializeVRAM
  91
  92   bx    r5
  93
  94   END