ArmPlatformPkg/PrePeiCore/PrePeiCoreEntryPoint.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 <AutoGen.h>
  18
  19   INCLUDE AsmMacroIoLib.inc
  20
  21   IMPORT  CEntryPoint
  22   EXPORT  _ModuleEntryPoint
  23
  24   PRESERVE8
  25   AREA    PrePeiCoreEntryPoint, CODE, READONLY
  26
  27 StartupAddr        DCD      CEntryPoint
  28
  29 SCC_SYS_SW         EQU      0x0004
  30
  31 _ModuleEntryPoint
  32   // Identify CPU ID
  33   mrc   p15, 0, r0, c0, c0, 5
  34   and   r0, #0xf
  35
  36 _SetupStack
  37   // Setup Stack for the 4 CPU cores
  38   LoadConstantToReg (FixedPcdGet32(PcdCPUCoresNonSecStackBase) ,r1)
  39   LoadConstantToReg (FixedPcdGet32(PcdCPUCoresNonSecStackSize) ,r2)
  40
  41   mov     r3,r0         // r3 = core_id
  42   mul     r3,r3,r2      // r3 = core_id * stack_size = offset from the stack base
  43   add     r3,r3,r1      // r3 = stack_base + offset
  44   add     r3,r3,r2,LSR #1   // r3 = stack_offset + (stack_size/2)   <-- the top half is for the heap
  45   mov     sp, r3
  46
  47   // The PEI Core Entry Point has been computed by GenFV and stored in the second entry of the Reset Vector
  48   LoadConstantToReg (FixedPcdGet32(PcdEmbeddedFdBaseAddress), r2)
  49   add   r2, r2, #4
  50   ldr   r1, [r2]
  51
  52   // move sec startup address into a data register
  53   // ensure we're jumping to FV version of the code (not boot remapped alias)
  54   ldr   r2, StartupAddr
  55
  56   // jump to SEC C code
  57   //    r0 = core_id
  58   //    r1 = pei_core_address
  59   blx   r2
  60
  61   END