mirror of
https://source.denx.de/u-boot/u-boot.git
synced 2025-11-04 02:11:25 +01:00
151 lines
3.4 KiB
ArmAsm
151 lines
3.4 KiB
ArmAsm
/*
|
|
* (C) Copyright 2007 Michal Simek
|
|
* (C) Copyright 2004 Atmark Techno, Inc.
|
|
*
|
|
* Michal SIMEK <monstr@monstr.eu>
|
|
* Yasushi SHOJI <yashi@atmark-techno.com>
|
|
*
|
|
* See file CREDITS for list of people who contributed to this
|
|
* project.
|
|
*
|
|
* 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 program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
.text
|
|
.global _start
|
|
_start:
|
|
mts rmsr, r0 /* disable cache */
|
|
addi r1, r0, CFG_INIT_SP_OFFSET
|
|
addi r1, r1, -4 /* Decrement SP to top of memory */
|
|
/* add opcode instruction for 32bit jump - 2 instruction imm & brai*/
|
|
addi r6, r0, 0xb0000000 /* hex b000 opcode imm */
|
|
swi r6, r0, 0x0 /* reset address */
|
|
swi r6, r0, 0x8 /* user vector exception */
|
|
swi r6, r0, 0x10 /* interrupt */
|
|
swi r6, r0, 0x20 /* hardware exception */
|
|
|
|
addi r6, r0, 0xb8080000 /* hew b808 opcode brai*/
|
|
swi r6, r0, 0x4 /* reset address */
|
|
swi r6, r0, 0xC /* user vector exception */
|
|
swi r6, r0, 0x14 /* interrupt */
|
|
swi r6, r0, 0x24 /* hardware exception */
|
|
|
|
#ifdef CFG_RESET_ADDRESS
|
|
/* reset address */
|
|
addik r6, r0, CFG_RESET_ADDRESS
|
|
sw r6, r1, r0
|
|
lhu r7, r1, r0
|
|
shi r7, r0, 0x2
|
|
shi r6, r0, 0x6
|
|
/*
|
|
* Copy U-Boot code to TEXT_BASE
|
|
* solve problem with sbrk_base
|
|
*/
|
|
#if (CFG_RESET_ADDRESS != TEXT_BASE)
|
|
addi r4, r0, __end
|
|
addi r5, r0, __text_start
|
|
rsub r4, r5, r4 /* size = __end - __text_start */
|
|
addi r6, r0, CFG_RESET_ADDRESS /* source address */
|
|
addi r7, r0, 0 /* counter */
|
|
4:
|
|
lw r8, r6, r7
|
|
sw r8, r5, r7
|
|
addi r7, r7, 0x4
|
|
cmp r8, r4, r7
|
|
blti r8, 4b
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef CFG_USR_EXCEP
|
|
/* user_vector_exception */
|
|
addik r6, r0, _exception_handler
|
|
sw r6, r1, r0
|
|
lhu r7, r1, r0
|
|
shi r7, r0, 0xa
|
|
shi r6, r0, 0xe
|
|
#endif
|
|
|
|
#ifdef CFG_INTC_0
|
|
/* interrupt_handler */
|
|
addik r6, r0, _interrupt_handler
|
|
sw r6, r1, r0
|
|
lhu r7, r1, r0
|
|
shi r7, r0, 0x12
|
|
shi r6, r0, 0x16
|
|
#endif
|
|
|
|
/* hardware exception */
|
|
addik r6, r0, _hw_exception_handler
|
|
sw r6, r1, r0
|
|
lhu r7, r1, r0
|
|
shi r7, r0, 0x22
|
|
shi r6, r0, 0x26
|
|
|
|
/* enable instruction and data cache */
|
|
mfs r12, rmsr
|
|
ori r12, r12, 0xa0
|
|
mts rmsr, r12
|
|
|
|
clear_bss:
|
|
/* clear BSS segments */
|
|
addi r5, r0, __bss_start
|
|
addi r4, r0, __bss_end
|
|
cmp r6, r5, r4
|
|
beqi r6, 3f
|
|
2:
|
|
swi r0, r5, 0 /* write zero to loc */
|
|
addi r5, r5, 4 /* increment to next loc */
|
|
cmp r6, r5, r4 /* check if we have reach the end */
|
|
bnei r6, 2b
|
|
3: /* jumping to board_init */
|
|
brai board_init
|
|
1: bri 1b
|
|
|
|
/*
|
|
* Read 16bit little endian
|
|
*/
|
|
.text
|
|
.global in16
|
|
.ent in16
|
|
.align 2
|
|
in16: lhu r3, r0, r5
|
|
bslli r4, r3, 8
|
|
bsrli r3, r3, 8
|
|
andi r4, r4, 0xffff
|
|
or r3, r3, r4
|
|
rtsd r15, 8
|
|
sext16 r3, r3
|
|
.end in16
|
|
|
|
/*
|
|
* Write 16bit little endian
|
|
* first parameter(r5) - address, second(r6) - short value
|
|
*/
|
|
.text
|
|
.global out16
|
|
.ent out16
|
|
.align 2
|
|
out16: bslli r3, r6, 8
|
|
bsrli r6, r6, 8
|
|
andi r3, r3, 0xffff
|
|
or r3, r3, r6
|
|
sh r3, r0, r5
|
|
rtsd r15, 8
|
|
or r0, r0, r0
|
|
.end out16
|