From 31ea780ee0df7c6b2eadc61287fe8a7dcb81ba52 Mon Sep 17 00:00:00 2001 From: Karl Kurbjun Date: Sun, 11 Nov 2007 17:58:13 +0000 Subject: Seperate the Gigabeat F/X crt0.s, cleanup some #ifdefs in app.lds, add an extra reg to the debug menu. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15579 a1c6a512-1295-4272-9138-f99709370657 --- firmware/target/arm/s3c2440/crt0.S | 355 +++++++++++++++++++++++++++++++++++++ 1 file changed, 355 insertions(+) create mode 100644 firmware/target/arm/s3c2440/crt0.S (limited to 'firmware/target/arm/s3c2440/crt0.S') diff --git a/firmware/target/arm/s3c2440/crt0.S b/firmware/target/arm/s3c2440/crt0.S new file mode 100644 index 0000000000..2c94fc4510 --- /dev/null +++ b/firmware/target/arm/s3c2440/crt0.S @@ -0,0 +1,355 @@ +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id$ + * + * Copyright (C) 2002 by Linus Nielsen Feltzing + * + * All files in this archive are subject to the GNU General Public License. + * See the file COPYING in the source tree root for full license agreement. + * + * 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: + +/* Arm bootloader and startup code based on startup.s from the iPodLinux loader + * + * Copyright (c) 2003, Daniel Palffy (dpalffy (at) rainstorm.org) + * Copyright (c) 2005, Bernard Leach + * + */ + msr cpsr, #0xd3 /* enter supervisor mode, disable IRQ */ + +#if !defined(BOOTLOADER) + /* Copy exception handler code to address 0 */ + ldr r2, =_vectorsstart + ldr r3, =_vectorsend + ldr r4, =_vectorscopy +1: + cmp r3, r2 + ldrhi r5, [r4], #4 + strhi r5, [r2], #4 + bhi 1b +#endif + +#if !defined(BOOTLOADER) && !defined(STUB) + /* Zero out IBSS */ + ldr r2, =_iedata + ldr r3, =_iend + mov r4, #0 +1: + cmp r3, r2 + strhi r4, [r2], #4 + bhi 1b + + /* Copy the IRAM */ + ldr r2, =_iramcopy + ldr r3, =_iramstart + ldr r4, =_iramend +1: + cmp r4, r3 + ldrhi r5, [r2], #4 + strhi r5, [r3], #4 + bhi 1b +#endif /* !BOOTLOADER, !STUB */ + + /* 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 + mov r3, sp + ldr r2, =stackbegin + ldr r4, =0xdeadbeef +1: + cmp r3, r2 + strhi r4, [r2], #4 + bhi 1b + +#ifdef BOOTLOADER +/* Code for ARM bootloader targets other than iPod go here */ + + /* Proper initialization pulled from 0x5070 */ + + /* BWSCON + * Reserved 0 + * Bank 0: + * Bus width 01 (16 bit) + * Bank 1: + * Buswidth 00 (8 bit) + * Disable wait 0 + * Not using UB/LB 0 + * Bank 2: + * Buswidth 10 (32 bit) + * Disable wait 0 + * Not using UB/LB 0 + * Bank 3: + * Buswidth 10 (32 bit) + * Disable wait 0 + * Use UB/LB 1 + * Bank 4: + * Buswidth 10 (32 bit) + * Disable wait 0 + * Use UB/LB 1 + * Bank 5: + * Buswidth 00 (8 bit) + * Disable wait 0 + * Not using UB/LB 0 + * Bank 6: + * Buswidth 10 (32 bit) + * Disable wait 0 + * Not using UB/LB 0 + * Bank 7: + * Buswidth 00 (8 bit) + * Disable wait 0 + * Not using UB/LB 0 + */ + ldr r2,=0x01055102 + mov r1, #0x48000000 + str r2, [r1] + + /* BANKCON0 + * Pagemode: normal (1 data) 00 + * Pagemode access cycle: 2 clocks 00 + * Address hold: 2 clocks 10 + * Chip selection hold time: 1 clock 10 + * Access cycle: 8 clocks 101 + * Chip select setup time: 1 clock 01 + * Address setup time: 0 clock 00 + */ + ldr r2,=0x00000D60 + str r2, [r1, #4] + + + /* BANKCON1 + * Pagemode: normal (1 data) 00 + * Pagemode access cycle: 2 clocks 00 + * Address hold: 0 clocks 00 + * Chip selection hold time: 0 clock 00 + * Access cycle: 1 clocks 000 + * Chip select setup time: 0 clocks 00 + * Address setup time: 0 clocks 00 + */ + ldr r2,=0x00000000 + str r2, [r1, #8] + + /* BANKCON2 + * Pagemode: normal (1 data) 00 + * Pagemode access cycle: 2 clocks 00 + * Address hold: 2 clocks 10 + * Chip selection hold time: 2 clocks 10 + * Access cycle: 14 clocks 111 + * Chip select setup time: 4 clocks 11 + * Address setup time: 0 clocks 00 + */ + ldr r2,=0x00001FA0 + str r2, [r1, #0xC] + + /* BANKCON3 */ + ldr r2,=0x00001D80 + str r2, [r1, #0x10] + /* BANKCON4 */ + str r2, [r1, #0x14] + + /* BANKCON5 */ + ldr r2,=0x00000000 + str r2, [r1, #0x18] + + /* BANKCON6/7 + * SCAN: 9 bit 01 + * Trcd: 3 clocks 01 + * Tcah: 0 clock 00 + * Tcoh: 0 clock 00 + * Tacc: 1 clock 000 + * Tcos: 0 clock 00 + * Tacs: 0 clock 00 + * MT: Sync DRAM 11 + */ + ldr r2,=0x00018005 + str r2, [r1, #0x1C] + /* BANKCON7 */ + str r2, [r1, #0x20] + + /* REFRESH */ + ldr r2,=0x00980501 + str r2, [r1, #0x24] + + /* BANKSIZE + * BK76MAP: 32M/32M 000 + * Reserved: 0 0 (was 1) + * SCLK_EN: always 1 (was 0) + * SCKE_EN: disable 0 + * Reserved: 0 0 + * BURST_EN: enabled 1 + */ + ldr r2,=0x00000090 + str r2, [r1, #0x28] + + /* MRSRB6 */ + ldr r2,=0x00000030 + str r2, [r1, #0x2C] + /* MRSRB7 */ + str r2, [r1, #0x30] + +#if 0 + /* This next part I am not sure of the purpose */ + + /* GPACON */ + mov r2,#0x01FFFCFF + str r2,=0x56000000 + + /* GPADAT */ + mov r2,#0x01FFFEFF + str r2,=0x56000004 + + /* MRSRB6 */ + mov r2,#0x00000000 + str r2,=0x4800002C + + /* GPADAT */ + ldr r2,=0x01FFFFFF + mov r1, #0x56000000 + str r2, [r1, #4] + + /* MRSRB6 */ + mov r2,#0x00000030 + str r2,=0x4800002C + + /* GPACON */ + mov r2,#0x01FFFFFF + str r2,=0x56000000 + + /* End of the unknown */ +#endif + + /* get the high part of our execute address */ + ldr r2, =0xffffff00 + and r4, pc, r2 + + /* Copy bootloader to safe area - 0x31000000 */ + mov r5, #0x30000000 + add r5, r5, #0x1000000 + ldr r6, = _dataend + sub r0, r6, r5 /* length of loader */ + add r0, r4, r0 /* r0 points to start of loader */ +1: + cmp r5, r6 + ldrcc r2, [r4], #4 + strcc r2, [r5], #4 + bcc 1b + + ldr pc, =start_loc /* jump to the relocated start_loc: */ + +start_loc: + bl main + +#else /* BOOTLOADER */ + + /* 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 to supervisor mode */ + msr cpsr_c, #0xd3 + ldr sp, =stackend + bl main + /* main() should never return */ + +/* Exception handlers. Will be copied to address 0 after memory remapping */ + .section .vectors,"aw" + ldr pc, [pc, #24] + ldr pc, [pc, #24] + ldr pc, [pc, #24] + ldr pc, [pc, #24] + ldr pc, [pc, #24] + ldr pc, [pc, #24] + ldr pc, [pc, #24] + ldr pc, [pc, #24] + + /* Exception vectors */ + .global vectors +vectors: + .word start + .word undef_instr_handler + .word software_int_handler + .word prefetch_abort_handler + .word data_abort_handler + .word reserved_handler + .word irq_handler + .word fiq_handler + + .text + +#ifndef STUB + .global irq + .global fiq + .global UIE +#endif + +/* 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 + +#ifdef STUB +UIE: + b UIE +#endif + +/* 256 words of IRQ stack */ + .space 256*4 +irq_stack: + +/* 256 words of FIQ stack */ + .space 256*4 +fiq_stack: + +#endif /* BOOTLOADER */ -- cgit v1.2.3