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#------------------------------------------------------------------------------
#
# Copyright (c) 2008-2009 Apple Inc. All rights reserved.
#
# All rights reserved. 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 <Library/PcdLib.h>
.text
.align 3
.globl ASM_PFX(CEntryPoint)
.globl ASM_PFX(_ModuleEntryPoint)
ASM_PFX(_ModuleEntryPoint):
//Disable L2 cache
mrc p15, 0, r0, c1, c0, 1 // read Auxiliary Control Register
bic r0, r0, #0x00000002 // disable L2 cache
mcr p15, 0, r0, c1, c0, 1 // store Auxiliary Control Register
//Enable Strict alignment checking & Instruction cache
mrc p15, 0, r0, c1, c0, 0
bic r0, r0, #0x00002300 /* clear bits 13, 9:8 (--V- --RS) */
bic r0, r0, #0x00000005 /* clear bits 0, 2 (---- -C-M) */
orr r0, r0, #0x00000002 /* set bit 1 (A) Align */
orr r0, r0, #0x00001000 /* set bit 12 (I) enable I-Cache */
mcr p15, 0, r0, c1, c0, 0
// Set CPU vectors to start of DRAM
mov r0, #0x80000000
mcr p15, 0, r0, c12, c0, 0
/* before we call C code, lets setup the stack pointer */
stack_pointer_setup:
//
// 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) ,r2) /* stack base arg2 */
LoadConstantToReg (FixedPcdGet32(PcdPrePiStackSize) ,r3) /* stack size arg3 */
add r4, r2, r3
//Enter IRQ mode and set up IRQ stack pointer
mov r0,#0x12|0x80|0x40
msr CPSR_c,r0
mov r13,r4
//Enter Abort mode and set up Abort stack pointer
mov r0,#0x17|0x80|0x40
msr CPSR_c,r0
sub r4, r4, #0x400
mov r13,r4
//Enter Undefined mode and set up Undefined stack pointer
mov r0,#0x1b|0x80|0x40
msr CPSR_c,r0
sub r4, r4, #0x400
mov r13,r4
//Enter SVC mode and set up SVC stack pointer
mov r0,#0x13|0x80|0x40
msr CPSR_c,r0
sub r4, r4, #0x400
mov r13,r4
//Enter System mode and set up System stack pointer
mov r0,#0x1f|0x80|0x40
msr CPSR_c,r0
sub r4, r4, #0x400
mov r13,r4
// Call C entry point
LoadConstantToReg (FixedPcdGet32(PcdMemorySize) ,r1) /* memory size arg1 */
LoadConstantToReg (FixedPcdGet32(PcdMemoryBase) ,r0) /* memory size arg0 */
blx ASM_PFX(CEntryPoint) /* Assume C code is ARM */
ShouldNeverGetHere:
/* _CEntryPoint should never return */
b ShouldNeverGetHere
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