MTD: New mapping driver for IBM 405GP 'Walnut' board.

Signed-off-by: Heikki O Lindholm <holindho@cs.helsinki.fi>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

drivers/mtd/maps/Kconfig

 # drivers/mtd/maps/Kconfig
-# $Id: Kconfig,v 1.39 2004/12/09 18:39:54 holindho Exp $
+# $Id: Kconfig,v 1.40 2004/12/09 20:01:05 holindho Exp $
 
 menu "Mapping drivers for chip access"
 	depends on MTD!=n
@@ -373,6 +373,14 @@ config MTD_ARCTIC
 	  Arctic board. If you have one of these boards and would like to
 	  use the flash chips on it, say 'Y'.
 
+config MTD_WALNUT
+	tristate "Flash device mapped on IBM 405GP Walnut"
+	depends on MTD_JEDECPROBE && PPC32 && 40x && WALNUT
+	help
+	  This enables access routines for the flash chips on the IBM 405GP
+	  Walnut board. If you have one of these boards and would like to
+	  use the flash chips on it, say 'Y'.
+
 config MTD_EBONY
 	tristate "Flash devices mapped on IBM 440GP Ebony"
 	depends on MTD_JEDECPROBE && PPC32 && 44x && EBONY

drivers/mtd/maps/Makefile

 #
 # linux/drivers/maps/Makefile
 #
-# $Id: Makefile.common,v 1.20 2004/11/24 19:42:51 rpurdie Exp $
+# $Id: Makefile.common,v 1.21 2004/12/09 20:01:05 holindho Exp $
 
 ifeq ($(CONFIG_MTD_COMPLEX_MAPPINGS),y)
 obj-$(CONFIG_MTD)		+= map_funcs.o
@@ -61,6 +61,7 @@ obj-$(CONFIG_MTD_EBONY)		+= ebony.o
 obj-$(CONFIG_MTD_OCOTEA)	+= ocotea.o
 obj-$(CONFIG_MTD_BEECH)		+= beech-mtd.o
 obj-$(CONFIG_MTD_ARCTIC)	+= arctic-mtd.o
+obj-$(CONFIG_MTD_WALNUT)        += walnut.o
 obj-$(CONFIG_MTD_H720X)		+= h720x-flash.o
 obj-$(CONFIG_MTD_SBC8240)	+= sbc8240.o
 obj-$(CONFIG_MTD_NOR_TOTO)	+= omap-toto-flash.o

drivers/mtd/maps/walnut.c

+/*
+ * $Id: walnut.c,v 1.2 2004/12/10 12:07:42 holindho Exp $
+ * 
+ * Mapping for Walnut flash
+ * (used ebony.c as a "framework")
+ * 
+ * Heikki Lindholm <holindho@infradead.org>
+ * 
+ * 
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/partitions.h>
+#include <linux/config.h>
+#include <linux/version.h>
+#include <asm/io.h>
+#include <asm/ibm4xx.h>
+#include <platforms/4xx/walnut.h>
+
+/* these should be in platforms/4xx/walnut.h ? */
+#define WALNUT_FLASH_ONBD_N(x)		(x & 0x02)
+#define WALNUT_FLASH_SRAM_SEL(x)	(x & 0x01)
+#define WALNUT_FLASH_LOW		0xFFF00000
+#define WALNUT_FLASH_HIGH		0xFFF80000
+#define WALNUT_FLASH_SIZE		0x80000
+
+static struct mtd_info *flash;
+
+static struct map_info walnut_map = {
+	.name =		"Walnut flash",
+	.size =		WALNUT_FLASH_SIZE,
+	.bankwidth =	1,
+};
+
+/* Actually, OpenBIOS is the last 128 KiB of the flash - better
+ * partitioning could be made */
+static struct mtd_partition walnut_partitions[] = {
+	{
+		.name =   "OpenBIOS",
+		.offset = 0x0,
+		.size =   WALNUT_FLASH_SIZE,
+		/*.mask_flags = MTD_WRITEABLE, */ /* force read-only */		
+	}
+};
+
+int __init init_walnut(void)
+{
+	u8 fpga_brds1;
+	void *fpga_brds1_adr;
+	void *fpga_status_adr;
+	unsigned long flash_base;
+
+	/* this should already be mapped (platform/4xx/walnut.c) */
+	fpga_status_adr = ioremap(WALNUT_FPGA_BASE, 8);
+	if (!fpga_status_adr)
+		return -ENOMEM;
+
+	fpga_brds1_adr = fpga_status_adr+5;
+	fpga_brds1 = readb(fpga_brds1_adr);
+	/* iounmap(fpga_status_adr); */
+
+	if (WALNUT_FLASH_ONBD_N(fpga_brds1)) {
+		printk("The on-board flash is disabled (U79 sw 5)!");
+		return -EIO;
+	}
+	if (WALNUT_FLASH_SRAM_SEL(fpga_brds1)) 
+		flash_base = WALNUT_FLASH_LOW;
+	else
+		flash_base = WALNUT_FLASH_HIGH;
+	
+	walnut_map.phys = flash_base;
+	walnut_map.virt =
+		(void __iomem *)ioremap(flash_base, walnut_map.size);
+
+	if (!walnut_map.virt) {
+		printk("Failed to ioremap flash.\n");
+		return -EIO;
+	}
+
+	simple_map_init(&walnut_map);
+
+	flash = do_map_probe("jedec_probe", &walnut_map);
+	if (flash) {
+		flash->owner = THIS_MODULE;
+		add_mtd_partitions(flash, walnut_partitions,
+					ARRAY_SIZE(walnut_partitions));
+	} else {
+		printk("map probe failed for flash\n");
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static void __exit cleanup_walnut(void)
+{
+	if (flash) {
+		del_mtd_partitions(flash);
+		map_destroy(flash);
+	}
+
+	if (walnut_map.virt) {
+		iounmap((void *)walnut_map.virt);
+		walnut_map.virt = 0;
+	}
+}
+
+module_init(init_walnut);
+module_exit(cleanup_walnut);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Heikki Lindholm <holindho@infradead.org>");
+MODULE_DESCRIPTION("MTD map and partitions for IBM 405GP Walnut boards");