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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
+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