/*
* This is based on the mvme-crt0.S file from libgloss/rs6000.
* crt0.S -- startup file for PowerPC systems.
*
* (c) 1998, Radstone Technology plc.
*
*
* This is an unpublished work the copyright in which vests
* in Radstone Technology plc. All rights reserved.
*
* The information contained herein is the property of Radstone
* Technology plc. and is supplied without liability for
* errors or omissions and no part may be reproduced, used or
* disclosed except as authorized by contract or other written
* permission. The copyright and the foregoing
* restriction on reproduction, use and disclosure extend to
* all the media in which this information may be
* embodied.
*
* Copyright (c) 1995 Cygnus Support
*
* The authors hereby grant permission to use, copy, modify, distribute,
* and license this software and its documentation for any purpose, provided
* that existing copyright notices are retained in all copies and that this
* notice is included verbatim in any distributions. No written agreement,
* license, or royalty fee is required for any of the authorized uses.
* Modifications to this software may be copyrighted by their authors
* and need not follow the licensing terms described here, provided that
* the new terms are clearly indicated on the first page of each file where
* they apply.
*
* $Id$
*/
#include <rtems/score/targopts.h> /* for PPC_USE_DATA_CACHE */
#include "ppc-asm.h"
#include "bsp.h"
.file "start.s"
.extern FUNC_NAME(atexit)
.globl FUNC_NAME(__atexit)
.section ".sdata","aw"
.align 2
FUNC_NAME(__atexit): /* tell C's eabi-ctor's we have an atexit function */
.long FUNC_NAME(atexit)@fixup /* and that it is to register __do_global_dtors */
.section ".fixup","aw"
.align 2
.long FUNC_NAME(__atexit)
.text
.globl _start
.type _start,@function
_start:
/* Set MSR */
/*
* Enable data and instruction address translation and floating point
*/
li r3,MSR_IR | MSR_DR | MSR_FP
mtmsr r3
/*
* The caches are already flushed by the firmware so just enable
*/
mfspr r3,HID0
#if PPC_USE_DATA_CACHE
/*
* Enable data and instruction cache
*/
ori r3,r3 ,H0_60X_ICE | H0_60X_DCE
#else
/*
* Enable instruction cache only
*/
ori r3,r3 ,H0_60X_ICE
#endif
mtspr HID0,r3
/* clear bss */
lis r6,__bss_start@h
ori r6,r6,__bss_start@l
lis r7,__bss_end@h
ori r7,r7,__bss_end@l
cmplw 1,r6,r7
bc 4,4,.Lbss_done
subf r8,r6,r7 /* number of bytes to zero */
srwi r9,r8,2 /* number of words to zero */
mtctr r9
li r0,0 /* zero to clear memory */
addi r6,r6,-4 /* adjust so we can use stwu */
.Lbss_loop:
stwu r0,4(r6) /* zero bss */
bdnz .Lbss_loop
.Lbss_done:
/* clear sbss */
lis r6,__sbss_start@h
ori r6,r6,__sbss_start@l
lis r7,__sbss_end@h
ori r7,r7,__sbss_end@l
cmplw 1,r6,r7
bc 4,4,.Lsbss_done
subf r8,r6,r7 /* number of bytes to zero */
srwi r9,r8,2 /* number of words to zero */
mtctr r9
li r0,0 /* zero to clear memory */
addi r6,r6,-4 /* adjust so we can use stwu */
.Lsbss_loop:
stwu r0,4(r6) /* zero sbss */
bdnz .Lsbss_loop
.Lsbss_done:
lis sp,__stack@h
ori sp,sp,__stack@l
/* set up initial stack frame */
addi sp,sp,-4 /* make sure we don't overwrite debug mem */
lis r0,0
stw r0,0(sp) /* clear back chain */
stwu sp,-56(sp) /* push another stack frame */
lis r5,environ@ha
la r5,environ@l(r5) /* environp */
li r4, 0 /* argv */
li r3, 0 /* argc */
/* Let her rip */
bl FUNC_NAME(boot_card)
/*
* This should never get reached
*/
/*
* Return MSR to its reset state
*/
li r3,0
mtmsr r3
isync
/*
* Call reset entry point
*/
lis r3,0xfff0
ori r3,r3,0x100
mtlr r3
blr
.Lstart:
.size _start,.Lstart-_start
.comm environ,4,4
