ArmPlatformPkg/PrePeiCore/Arm/PrePeiCoreEntryPoint.asm

   1 //
   2 //  Copyright (c) 2011-2013, 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 <AutoGen.h>
  18
  19   INCLUDE AsmMacroIoLib.inc
  20
  21   IMPORT  CEntryPoint
  22   IMPORT  ArmPlatformGetCorePosition
  23   IMPORT  ArmPlatformIsPrimaryCore
  24   IMPORT  ArmReadMpidr
  25   IMPORT  ArmPlatformPeiBootAction
  26   EXPORT  _ModuleEntryPoint
  27
  28   PRESERVE8
  29   AREA    PrePeiCoreEntryPoint, CODE, READONLY
  30
  31 StartupAddr        DCD      CEntryPoint
  32
  33 _ModuleEntryPoint
  34   // Do early platform specific actions
  35   bl    ArmPlatformPeiBootAction
  36
  37   // Identify CPU ID
  38   bl    ArmReadMpidr
  39   // Keep a copy of the MpId register value
  40   mov   r5, r0
  41
  42   // Is it the Primary Core ?
  43   bl    ArmPlatformIsPrimaryCore
  44
  45   // Get the top of the primary stacks (and the base of the secondary stacks)
  46   LoadConstantToReg (FixedPcdGet32(PcdCPUCoresStackBase), r1)
  47   LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2)
  48   add   r1, r1, r2
  49
  50   // r0 is equal to 1 if I am the primary core
  51   cmp   r0, #1
  52   beq   _SetupPrimaryCoreStack
  53
  54 _SetupSecondaryCoreStack
  55   // r1 contains the base of the secondary stacks
  56
  57   // Get the Core Position
  58   mov   r6, r1      // Save base of the secondary stacks
  59   mov   r0, r5
  60   bl    ArmPlatformGetCorePosition
  61   // The stack starts at the top of the stack region. Add '1' to the Core Position to get the top of the stack
  62   add   r0, r0, #1
  63
  64   // StackOffset = CorePos * StackSize
  65   LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), r2)
  66   mul   r0, r0, r2
  67   // SP = StackBase + StackOffset
  68   add   sp, r6, r0
  69
  70 _PrepareArguments
  71   // The PEI Core Entry Point has been computed by GenFV and stored in the second entry of the Reset Vector
  72   LoadConstantToReg (FixedPcdGet32(PcdFvBaseAddress), r2)
  73   add   r2, r2, #4
  74   ldr   r1, [r2]
  75
  76   // Move sec startup address into a data register
  77   // Ensure we're jumping to FV version of the code (not boot remapped alias)
  78   ldr   r3, StartupAddr
  79
  80   // Jump to PrePeiCore C code
  81   //    r0 = mp_id
  82   //    r1 = pei_core_address
  83   mov   r0, r5
  84   blx   r3
  85
  86 _SetupPrimaryCoreStack
  87   // r1 contains the top of the primary stack
  88   LoadConstantToReg (FixedPcdGet32(PcdPeiGlobalVariableSize), r2)
  89
  90   // The reserved space for global variable must be 8-bytes aligned for pushing
  91   // 64-bit variable on the stack
  92   SetPrimaryStack (r1, r2, r3)
  93   b     _PrepareArguments
  94
  95 _NeverReturn
  96   b _NeverReturn
  97
  98   END