ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressSecLibRTSM/AArch64/RTSMFoundationBoot.S

   1 //
   2 //  Copyright (c) 2011-2014, 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 <AsmMacroIoLibV8.h>
  15 #include <Base.h>
  16 #include <Library/ArmPlatformLib.h>
  17 #include <AutoGen.h>
  18 #include <ArmPlatform.h>
  19
  20 .text
  21 .align 3
  22
  23 GCC_ASM_EXPORT(ArmPlatformSecBootAction)
  24 GCC_ASM_EXPORT(ArmPlatformSecBootMemoryInit)
  25 GCC_ASM_EXPORT(ArmSecMpCoreSecondariesWrite)
  26 GCC_ASM_EXPORT(ArmSecMpCoreSecondariesRead)
  27
  28 /**
  29   Call at the beginning of the platform boot up
  30
  31   This function allows the firmware platform to do extra actions at the early
  32   stage of the platform power up.
  33
  34   Note: This function must be implemented in assembler as there is no stack set up yet
  35
  36 **/
  37 ASM_PFX(ArmPlatformSecBootAction):
  38   ret
  39
  40 /**
  41   Initialize the memory where the initial stacks will reside
  42
  43   This memory can contain the initial stacks (Secure and Secure Monitor stacks).
  44   In some platform, this region is already initialized and the implementation of this function can
  45   do nothing. This memory can also represent the Secure RAM.
  46   This function is called before the stack has been set up. Its implementation must ensure the stack
  47   pointer is not used (probably required to use assembly language)
  48
  49 **/
  50 ASM_PFX(ArmPlatformSecBootMemoryInit):
  51   // The SMC does not need to be initialized for RTSM
  52   ret
  53
  54
  55 // NOTE:
  56 // The foundation model does not have the VE_SYS_REGS like all the other VE
  57 // platforms. We pick a spot in RAM that *should* be safe in the simple case
  58 // of no UEFI apps interfering (Only the Linux loader getting used). By the
  59 // time we come to load Linux we should have all the cores in a safe place.
  60 // The image expects to be loaded at 0xa0000000. We also place the mailboxes
  61 // here as it does not matter if we corrupt the image at this time.
  62 // NOTE also see: "ArmVExpressLibRTSM/RTSMFoundation.c"
  63
  64 /* Write the flag register used to start Secondary cores */
  65 ASM_PFX(ArmSecMpCoreSecondariesWrite):
  66   ldr x1, =0xa0000000
  67   str w0, [x1]
  68   ret
  69
  70
  71 /* Read the flag register used to start Secondary cores */
  72 ASM_PFX(ArmSecMpCoreSecondariesRead):
  73   ldr x1, =0xa0000000
  74   ldr w0, [x1]
  75   ret