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#------------------------------------------------------------------------------ 
#
# ARM EB Entry point. Reset vector in FV header will brach to
# _ModuleEntryPoint. 
#
# We use crazy macros, like LoadConstantToReg, since Xcode assembler 
# does not support = assembly syntax for ldr.
#
# Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
#
# This program and the accompanying materials
# are licensed and made available under the terms and conditions of the BSD License
# which accompanies this distribution.  The full text of the license may be found at
# http://opensource.org/licenses/bsd-license.php
#
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#
#------------------------------------------------------------------------------

#include <AsmMacroIoLib.h>
#include <Base.h>
#include <Library/PcdLib.h>
#include <ArmEb/ArmEb.h>

.text
.align 3

.globl ASM_PFX(CEntryPoint)
.globl ASM_PFX(_ModuleEntryPoint)
.globl ASM_PFX(StartupAddr)


ASM_PFX(StartupAddr):   .word ASM_PFX(CEntryPoint)

ASM_PFX(_ModuleEntryPoint):
 
  // Turn off remapping NOR to 0. We can now use DRAM in low memory
  // CAN'T DO THIS HERE -- BRANCH FROM RESET VECTOR IS RELATIVE AND REMAINS IN REMAPPED NOR
  //MmioOr32 (0x10001000 ,BIT8) //EB_SP810_CTRL_BASE

  // Enable NEON register in case folks want to use them for optimizations (CopyMem)
  mrc     p15, 0, r0, c1, c0, 2
  orr     r0, r0, #0x00f00000   // Enable VFP access (V* instructions)
  mcr     p15, 0, r0, c1, c0, 2
  mov     r0, #0x40000000       // Set EN bit in FPEXC
  mcr     p10,#0x7,r0,c8,c0,#0  // msr     FPEXC,r0 in ARM assembly
   
  // Set CPU vectors to 0 (which is currently flash)
  LoadConstantToReg (FixedPcdGet32(PcdCpuVectorBaseAddress) ,r0) // Get vector base
  mcr     p15, 0, r0, c12, c0, 0
  isb                               // Sync changes to control registers

  //
  // Set stack based on PCD values. Need to do it this way to make C code work 
  // when it runs from FLASH. 
  //  
  LoadConstantToReg (FixedPcdGet32(PcdPrePiStackBase) ,r0)    // temp ram base  arg 0 TODO: change "stackbase" to "temprambase"
  LoadConstantToReg (FixedPcdGet32(PcdPrePiStackSize) ,r1)    // temp ram size  arg 1
  lsr     r3, r1, #1   // r4 = size of temp mem / 2
  add     r3, r3, r0  // r2 = temp ram base + r4
  mov     r13, r3     // result: stack pointer = temp ram base + (size of temp mem / 2)
    
  // lr points to area in reset vector block containing PEI core address
  ldr     r2, [lr]  // pei core   arg 3
 
  // move sec startup address into a data register
  // ensure we're jumping to FV version of the code (not boot remapped alias)
  ldr   r4, ASM_PFX(StartupAddr) // Extra level of indirection fixes Xcode relocation issue

  // jump to SEC C code
  blx   r4
  

ASM_PFX(ShouldNeverGetHere):
  // _CEntryPoint should never return 
  b       ASM_PFX(ShouldNeverGetHere)