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/*
* (C) Copyright 2008
* Graeme Russ, graeme.russ@gmail.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
*/
/*
* 16bit initialization code.
* This code have to map the area of the boot flash
* that is used by U-boot to its final destination.
*/
/* #include <asm/ic/sc520_defs.h> */
#include "hardware.h"
.text
.section .start16, "ax"
.code16
.globl board_init16
board_init16:
/* Alias MMCR to 0xdf000 */
movw $0xfffc, %dx
movl $0x800df0cb, %eax
outl %eax, %dx
/* Set ds to point to MMCR alias */
movw $0xdf00, %ax
movw %ax, %ds
/* Map PAR for Boot Flash (BOOTCS, 512kB @ 0x380000000) */
movl $0x00c0, %edi /* SC520_PAR14 */
movl $0x8bfff800, %eax /* TODO: Check this */
movl %eax, (%di)
/* Map PAR for LED, Hex Switches (GPCS6, 20 Bytes @ 0x1000) */
movl $0x00c4, %edi /* SC520_PAR15 */
movl $0x38201000, %eax
movl %eax, (%di)
/* Disable SDRAM write buffer */
movw $0x0040, %di /* SC520_DBCTL */
xorw %ax, %ax
movb %al, (%di)
/* Disabe MMCR alias */
movw $0xfffc, %dx
movl $0x000000cb, %eax
outl %eax, %dx
/* the return address is stored in bp */
jmp *%bp
.section .bios, "ax"
.code16
.globl realmode_reset
.hidden realmode_reset
.type realmode_reset, @function
realmode_reset:
/* Alias MMCR to 0xdf000 */
movw $0xfffc, %dx
movl $0x800df0cb, %eax
outl %eax, %dx
/* Set ds to point to MMCR alias */
movw $0xdf00, %ax
movw %ax, %ds
/* issue software reset thorugh MMCR */
movl $0xd72, %edi
movb $0x01, %al
movb %al, (%di)
1: hlt
jmp 1
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