rockbox/firmware/target/arm/s5l8700/crt0.S
Frank Gevaerts 3637ef9b32 First reading out of the touchpad!
disabled power handling for now, so the device will power off when unplugged again (because there is no other poweroff method provided)


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@18480 a1c6a512-1295-4272-9138-f99709370657
2008-09-10 19:08:46 +00:00

131 lines
3.3 KiB
ArmAsm

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2008 by Marcoen Hirschberg
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "config.h"
#include "cpu.h"
.section .init.text,"ax",%progbits
.global start
start:
/* Exception vectors */
b newstart
b undef_instr_handler
b software_int_handler
b prefetch_abort_handler
b data_abort_handler
b reserved_handler
b irq_handler
b fiq_handler
.word 0x43554644 /* DFUC */
newstart:
msr cpsr_c, #0xd3 /* enter supervisor mode, disable IRQ/FIQ */
#if 0
/* set PWRON to 1 */
ldr r1, =0x3CF00014
ldr r2, [r1]
orr r2, r2, #0x8
str r2, [r1]
ldr r1, =0x3CF00010
ldr r2, [r1]
bic r2, r2, #0xf000
orr r2, r2, #0x1000
str r2, [r1]
#endif
/* Initialise bss section to zero */
ldr r2, =_edata
ldr r3, =_end
mov r4, #0
1:
cmp r3, r2
strhi r4, [r2], #4
bhi 1b
/* Set up some stack and munge it with 0xdeadbeef */
ldr sp, =stackend
ldr r2, =stackbegin
ldr r3, =0xdeadbeef
1:
cmp sp, r2
strhi r3, [r2], #4
bhi 1b
/* Set up stack for IRQ mode */
msr cpsr_c, #0xd2
ldr sp, =irq_stack
/* Set up stack for FIQ mode */
msr cpsr_c, #0xd1
ldr sp, =fiq_stack
/* Let abort and undefined modes use IRQ stack */
msr cpsr_c, #0xd7
ldr sp, =irq_stack
msr cpsr_c, #0xdb
ldr sp, =irq_stack
/* Switch back to supervisor mode */
msr cpsr_c, #0xd3
bl main
.text
/* .global UIE*/
/* All illegal exceptions call into UIE with exception address as first
* parameter. This is calculated differently depending on which exception
* we're in. Second parameter is exception number, used for a string lookup
* in UIE. */
undef_instr_handler:
mov r0, lr
mov r1, #0
b UIE
/* We run supervisor mode most of the time, and should never see a software
* exception being thrown. Perhaps make it illegal and call UIE? */
software_int_handler:
reserved_handler:
movs pc, lr
prefetch_abort_handler:
sub r0, lr, #4
mov r1, #1
b UIE
data_abort_handler:
sub r0, lr, #8
mov r1, #2
b UIE
/* 256 words of IRQ stack */
.space 256*4
irq_stack:
/* 256 words of FIQ stack */
.space 256*4
fiq_stack:
end:
/*.word 0xA5A5A5A5
.word 0x5A5A5A5A*/