From c620c01e96814558470698ed5cab1bf2f504d1b5 Mon Sep 17 00:00:00 2001
From: Graeme Russ <graeme.russ@gmail.com>
Date: Sun, 7 Dec 2008 10:28:57 +1100
Subject: Added initial eNET board support

Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
---
 board/eNET/eNET_start16.S | 90 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 board/eNET/eNET_start16.S

(limited to 'board/eNET/eNET_start16.S')

diff --git a/board/eNET/eNET_start16.S b/board/eNET/eNET_start16.S
new file mode 100644
index 0000000..48e4d83
--- /dev/null
+++ b/board/eNET/eNET_start16.S
@@ -0,0 +1,90 @@
+/*
+ * (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
-- 
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