ArmPlatformPkg/PrePeiCore/Arm/PrePeiCoreEntryPoint.S

   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
  16 ASM_FUNC(_ModuleEntryPoint)
  17   // Do early platform specific actions
  18   bl    ASM_PFX(ArmPlatformPeiBootAction)
  19
  20   // Identify CPU ID
  21   bl    ASM_PFX(ArmReadMpidr)
  22   // Keep a copy of the MpId register value
  23   mov   r5, r0
  24
  25   // Is it the Primary Core ?
  26   bl    ASM_PFX(ArmPlatformIsPrimaryCore)
  27
  28   // Get the top of the primary stacks (and the base of the secondary stacks)
  29   MOV32 (r1, FixedPcdGet64(PcdCPUCoresStackBase) + FixedPcdGet32(PcdCPUCorePrimaryStackSize))
  30
  31   // r0 is equal to 1 if I am the primary core
  32   cmp   r0, #1
  33   beq   _SetupPrimaryCoreStack
  34
  35 _SetupSecondaryCoreStack:
  36   // r1 contains the base of the secondary stacks
  37
  38   // Get the Core Position
  39   mov   r6, r1      // Save base of the secondary stacks
  40   mov   r0, r5
  41   bl    ASM_PFX(ArmPlatformGetCorePosition)
  42   // The stack starts at the top of the stack region. Add '1' to the Core Position to get the top of the stack
  43   add   r0, r0, #1
  44
  45   // StackOffset = CorePos * StackSize
  46   MOV32 (r2, FixedPcdGet32(PcdCPUCoreSecondaryStackSize))
  47   mul   r0, r0, r2
  48   // SP = StackBase + StackOffset
  49   add   sp, r6, r0
  50
  51 _PrepareArguments:
  52   // The PEI Core Entry Point has been computed by GenFV and stored in the second entry of the Reset Vector
  53   MOV32 (r2, FixedPcdGet32(PcdFvBaseAddress))
  54   ldr   r1, [r2, #4]
  55
  56   // Move sec startup address into a data register
  57   // Ensure we're jumping to FV version of the code (not boot remapped alias)
  58   ldr   r3, =ASM_PFX(CEntryPoint)
  59
  60   // Jump to PrePeiCore C code
  61   //    r0 = mp_id
  62   //    r1 = pei_core_address
  63   mov   r0, r5
  64   blx   r3
  65
  66 _SetupPrimaryCoreStack:
  67   mov   sp, r1
  68   MOV32 (r8, FixedPcdGet64 (PcdCPUCoresStackBase))
  69   MOV32 (r9, FixedPcdGet32 (PcdInitValueInTempStack))
  70   mov   r10, r9
  71   mov   r11, r9
  72   mov   r12, r9
  73 0:stm   r8!, {r9-r12}
  74   cmp   r8, r1
  75   blt   0b
  76   b     _PrepareArguments
  77
  78 _NeverReturn:
  79   b _NeverReturn