mirror of
https://github.com/smaeul/u-boot.git
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91 lines
2.2 KiB
ArmAsm
91 lines
2.2 KiB
ArmAsm
/*
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* (C) Copyright 2008
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* Graeme Russ, graeme.russ@gmail.com.
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*
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* See file CREDITS for list of people who contributed to this
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* project.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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* MA 02111-1307 USA
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*/
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/*
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* 16bit initialization code.
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* This code have to map the area of the boot flash
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* that is used by U-boot to its final destination.
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*/
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/* #include <asm/ic/sc520_defs.h> */
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#include "hardware.h"
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.text
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.section .start16, "ax"
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.code16
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.globl board_init16
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board_init16:
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/* Alias MMCR to 0xdf000 */
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movw $0xfffc, %dx
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movl $0x800df0cb, %eax
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outl %eax, %dx
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/* Set ds to point to MMCR alias */
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movw $0xdf00, %ax
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movw %ax, %ds
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/* Map PAR for Boot Flash (BOOTCS, 512kB @ 0x380000000) */
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movl $0x00c0, %edi /* SC520_PAR14 */
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movl $0x8bfff800, %eax /* TODO: Check this */
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movl %eax, (%di)
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/* Map PAR for LED, Hex Switches (GPCS6, 20 Bytes @ 0x1000) */
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movl $0x00c4, %edi /* SC520_PAR15 */
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movl $0x38201000, %eax
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movl %eax, (%di)
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/* Disable SDRAM write buffer */
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movw $0x0040, %di /* SC520_DBCTL */
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xorw %ax, %ax
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movb %al, (%di)
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/* Disabe MMCR alias */
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movw $0xfffc, %dx
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movl $0x000000cb, %eax
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outl %eax, %dx
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/* the return address is stored in bp */
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jmp *%bp
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.section .bios, "ax"
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.code16
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.globl realmode_reset
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realmode_reset:
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/* Alias MMCR to 0xdf000 */
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movw $0xfffc, %dx
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movl $0x800df0cb, %eax
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outl %eax, %dx
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/* Set ds to point to MMCR alias */
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movw $0xdf00, %ax
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movw %ax, %ds
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/* issue software reset thorugh MMCR */
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movl $0xd72, %edi
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movb $0x01, %al
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movb %al, (%di)
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1: hlt
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jmp 1
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