[PATCH] cmx270-nand: Make CMDLINE_PARTS usable

[PATCH] cmx270-nand: Make CMDLINE_PARTS usable

[Raphael Assenat]

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This patch gives a name to the cmx270 nand mtd, making it possible to use command line
partitioning.

eg:
mtdparts=cmx270-nand:32m(root),8m(data),-(spare)"

does not work without this patch. The default (one full device partition)
hardcoded in the driver is used.


Signed-off-by: Raphael Assenat <raph@8d.com>

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This patch gives a name to the cmx270 nand mtd, making it possible to use command line
partitioning. 

eg:
mtdparts=cmx270-nand:32m(root),8m(data),-(spare)"

does not work without this patch. The default (one full device partition)
hardcoded in the driver is used.


Signed-off-by: Raphael Assenat <raph@8d.com>

--- linux-2.6.18-rc2-8d-unionfs/drivers/mtd/nand/cmx270-nand.c	2006-08-17 15:32:02.000000000 -0400
+++ linux-2.6.18-rc2-8d2/drivers/mtd/nand/cmx270-nand.c	2006-09-05 10:23:16.000000000 -0400
@@ -218,6 +218,7 @@
 		goto err2;
 	}
 
+	cmx270_nand_mtd->name = "cmx270-nand";
 #ifdef CONFIG_MTD_CMDLINE_PARTS
 	mtd_parts_nb = parse_mtd_partitions(cmx270_nand_mtd, part_probes,
 					    &mtd_parts, 0);

Re: [PATCH] cmx270-nand: Make CMDLINE_PARTS usable

[David Woodhouse]

On Wed, 2006-09-13 at 08:50 -0400, Raphael Assenat wrote:
> This patch gives a name to the cmx270 nand mtd, making it possible to
> use command line partitioning.

Er, there _is_ no cmx270 nand board driver in my tree.

-- 
dwmw2

Re: [PATCH] cmx270-nand: Make CMDLINE_PARTS usable

[Raphael Assenat]

David Woodhouse wrote:
> On Wed, 2006-09-13 at 08:50 -0400, Raphael Assenat wrote:
> 
>>This patch gives a name to the cmx270 nand mtd, making it possible to
>>use command line partitioning.
> 
> 
> Er, there _is_ no cmx270 nand board driver in my tree.
> 
Oh, sorry. My patch applies over the patch Mike Rapoport sent to the list on July 18
([PATCH] [MTD] CM-x270 NAND flash support), which I thought was already accepted. Was 
there anything wrong with it? Maybe you just missed it...

I also sent a patch to the list on July 21 which added NAND flash support for the cm-x255 
boards ([PATCH] Add support for NAND flash on cm-x255) but received no feedback. I can 
resend it if you wish.

(BTW, every time I send to the linux-mtd list my message is held for moderator approval 
for reason 'Message has a suspicious header'. Who should I contact for more information? 
I'd like to know exactly what header(s) is/are 'suspicious' and fix them if possible).

Best regards,

-- 
Raphael Assenat
8D Technologies Inc.

Re: [PATCH] cmx270-nand: Make CMDLINE_PARTS usable

[David Woodhouse]

On Fri, 2006-09-22 at 10:15 -0400, Raphael Assenat wrote:
> Oh, sorry. My patch applies over the patch Mike Rapoport sent to the list on July 18
> ([PATCH] [MTD] CM-x270 NAND flash support), which I thought was already accepted. Was 
> there anything wrong with it? Maybe you just missed it...
> 
> I also sent a patch to the list on July 21 which added NAND flash support for the cm-x255 
> boards ([PATCH] Add support for NAND flash on cm-x255) but received no feedback. I can 
> resend it if you wish.

July and August weren't really a good time for sending stuff that you
expect me to pay attention to; sorry. Yes -- please retest and resend.

Can you explain how these two boards differ, and why they need two
separate drivers?

> (BTW, every time I send to the linux-mtd list my message is held for moderator approval 
> for reason 'Message has a suspicious header'. Who should I contact for more information? 
> I'd like to know exactly what header(s) is/are 'suspicious' and fix them if possible).

It just doesn't like attachments. Send patches inline and they shouldn't
get trapped.

-- 
dwmw2

Re: [PATCH] cmx270-nand: Make CMDLINE_PARTS usable

[Raphael Assenat]

David Woodhouse wrote:
> On Fri, 2006-09-22 at 10:15 -0400, Raphael Assenat wrote:
> 
>>Oh, sorry. My patch applies over the patch Mike Rapoport sent to the list on July 18
>>([PATCH] [MTD] CM-x270 NAND flash support), which I thought was already accepted. Was 
>>there anything wrong with it? Maybe you just missed it...
>>
>>I also sent a patch to the list on July 21 which added NAND flash support for the cm-x255 
>>boards ([PATCH] Add support for NAND flash on cm-x255) but received no feedback. I can 
>>resend it if you wish.
> 
> 
> July and August weren't really a good time for sending stuff that you
> expect me to pay attention to; sorry. Yes -- please retest and resend.
> 
> Can you explain how these two boards differ, and why they need two
> separate drivers?
Yes.

NAND on cm-x255:
- Uses physical address 0x04000000
- CS, ALE, CLE and RB mapped to pxa GPIOs 5,4,3,10 respectively.

NAND on cm-x270:
- CS and RB mapped to pxa GPIOs 11 and 89
- Read/Write with ALE/CLE inactive: 0x04000000
- Read/Write with ALE active: 0x04000008
- Read/Write with CLE active: 0x04000004

The base address is the same, but GPIOs used differ and the control signals
are controlled differently.


>>(BTW, every time I send to the linux-mtd list my message is held for moderator approval 
>>for reason 'Message has a suspicious header'. Who should I contact for more information? 
>>I'd like to know exactly what header(s) is/are 'suspicious' and fix them if possible).
> 
> 
> It just doesn't like attachments. Send patches inline and they shouldn't
> get trapped.

Best regards,

-- 
Raphael Assenat
8D Technologies Inc.

[PATCH][RESEND] [MTD] CM-x270 NAND flash support (Was [PATCH] cmx270-nand: Make CMDLINE_PARTS usable)

[Mike Rapoport]

David Woodhouse wrote:

>On Fri, 2006-09-22 at 10:15 -0400, Raphael Assenat wrote:
>  
>
>>Oh, sorry. My patch applies over the patch Mike Rapoport sent to the list on July 18
>>([PATCH] [MTD] CM-x270 NAND flash support), which I thought was already accepted. Was 
>>there anything wrong with it? Maybe you just missed it...
>>
>>I also sent a patch to the list on July 21 which added NAND flash support for the cm-x255 
>>boards ([PATCH] Add support for NAND flash on cm-x255) but received no feedback. I can 
>>resend it if you wish.
>>    
>>
>
>July and August weren't really a good time for sending stuff that you
>expect me to pay attention to; sorry. Yes -- please retest and resend.
>  
>
This patch provides MTD support for NAND flash device on CM-x270 modules.
This is the same patch I've sent earlier.
Unfortunately I'm currently overloaded to update it for the recent 
kernels and retest.

>Can you explain how these two boards differ, and why they need two
>separate drivers?
>
>  
>
>>(BTW, every time I send to the linux-mtd list my message is held for moderator approval 
>>for reason 'Message has a suspicious header'. Who should I contact for more information? 
>>I'd like to know exactly what header(s) is/are 'suspicious' and fix them if possible).
>>    
>>
>
>It just doesn't like attachments. Send patches inline and they shouldn't
>get trapped.
>
>  
>
-- 

Sincerely yours,
Mike Rapoport


=========================================================
This patch provides MTD support for NAND flash device on CM-x270 modules.


Signed-off-by: Mike Rapoport <mike@compulab.co.il>

=========================================================

 drivers/mtd/nand/Kconfig       |    4 +
 drivers/mtd/nand/Makefile      |    1 
 drivers/mtd/nand/cmx270-nand.c |  271 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 276 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 3db77ee..4c212fd 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -232,6 +232,10 @@ config MTD_NAND_CS553X
 
 	  If you say "m", the module will be called "cs553x_nand.ko".
 
+config MTD_NAND_CM_X270
+	tristate "Support for NAND Flash on CM-X270 modules"
+	depends on MTD_NAND && MACH_CM_X270
+
 config MTD_NAND_NANDSIM
 	tristate "Support for NAND Flash Simulator"
 	depends on MTD_NAND && MTD_PARTITIONS
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index f747593..f2718aa 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -22,5 +22,6 @@ obj-$(CONFIG_MTD_NAND_TS7250)		+= ts7250
 obj-$(CONFIG_MTD_NAND_NANDSIM)		+= nandsim.o
 obj-$(CONFIG_MTD_NAND_CS553X)		+= cs553x_nand.o
 obj-$(CONFIG_MTD_NAND_NDFC)		+= ndfc.o
+obj-$(CONFIG_MTD_NAND_CM_X270)		+= cmx270-nand.o
 
 nand-objs = nand_base.o nand_bbt.o
diff --git a/drivers/mtd/nand/cmx270-nand.c b/drivers/mtd/nand/cmx270-nand.c
new file mode 100644
index 0000000..8a1911c
--- /dev/null
+++ b/drivers/mtd/nand/cmx270-nand.c
@@ -0,0 +1,271 @@
+/*
+ *  linux/drivers/mtd/nand/cmx270-nand.c
+ *
+ *  Copyright (C) 2006 Compulab, Ltd.
+ *  Mike Rapoport <mike@compulab.co.il>
+ *
+ *  Derived from drivers/mtd/nand/h1910.c
+ *       Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
+ *       Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Overview:
+ *   This is a device driver for the NAND flash device found on the
+ *   CM-X270 board.
+ */
+
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include <asm/arch/hardware.h>
+#include <asm/arch/pxa-regs.h>
+
+#define GPIO_NAND_CS	(11)
+#define GPIO_NAND_RB	(89)
+
+/* This macro needed to ensure in-order operation of GPIO and local
+ * bus. Without both asm command and dummy uncached read there're
+ * states when NAND access is broken. I've looked for such macro(s) in
+ * include/asm-arm but found nothing approptiate.
+ * dmac_clean_range is close, but is makes cache invalidation
+ * unnecessary here and it cannot be used in module
+ */
+#define DRAIN_WB() \
+	do { \
+		unsigned char dummy; \
+		asm volatile ("mcr p15, 0, r0, c7, c10, 4":::"r0"); \
+		dummy=*((unsigned char*)UNCACHED_ADDR); \
+	} while(0)
+
+/* MTD structure for CM-X270 board */
+static struct mtd_info *cmx270_nand_mtd;
+
+/* remaped IO address of the device */
+static void __iomem *cmx270_nand_io;
+
+/*
+ * Define static partitions for flash device
+ */
+static struct mtd_partition partition_info[] = {
+	{
+		.name	= "cmx270-0",
+		.offset	= 0,
+		.size	= MTDPART_SIZ_FULL
+	}
+};
+#define NUM_PARTITIONS (ARRAY_SIZE(partition_info))
+
+const char *part_probes[] = { "cmdlinepart", NULL };
+
+static 	u_char cmx270_read_byte(struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+
+	return (readl(this->IO_ADDR_R) >> 16);
+}
+
+static void cmx270_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i=0; i<len; i++)
+		writel((*buf++ << 16), this->IO_ADDR_W);
+}
+
+static void cmx270_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i=0; i<len; i++)
+		*buf++ = readl(this->IO_ADDR_R) >> 16;
+}
+
+static int cmx270_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i=0; i<len; i++)
+		if (buf[i] != (u_char)(readl(this->IO_ADDR_R) >> 16))
+			return -EFAULT;
+
+	return 0;
+}
+
+static inline void nand_cs_on(void)
+{
+	GPCR(GPIO_NAND_CS) = GPIO_bit(GPIO_NAND_CS);
+}
+
+static void nand_cs_off(void)
+{
+	DRAIN_WB();
+
+	GPSR(GPIO_NAND_CS) = GPIO_bit(GPIO_NAND_CS);
+}
+
+/*
+ *	hardware specific access to control-lines
+ */
+static void cmx270_hwcontrol(struct mtd_info *mtd, int dat,
+			     unsigned int ctrl)
+{
+	struct nand_chip* this = mtd->priv;
+	unsigned int nandaddr = (unsigned int)this->IO_ADDR_W;
+
+	DRAIN_WB();
+
+	if (ctrl & NAND_CTRL_CHANGE) {
+		if ( ctrl & NAND_ALE )
+			nandaddr |=  (1 << 3);
+		else
+			nandaddr &= ~(1 << 3);
+		if ( ctrl & NAND_CLE )
+			nandaddr |=  (1 << 2);
+		else
+			nandaddr &= ~(1 << 2);
+		if ( ctrl & NAND_NCE )
+			nand_cs_on();
+		else
+			nand_cs_off();
+	}
+
+	DRAIN_WB();
+	this->IO_ADDR_W = (void __iomem*)nandaddr;
+	if (dat != NAND_CMD_NONE)
+		writel((dat << 16), this->IO_ADDR_W);
+
+	DRAIN_WB();
+}
+
+/*
+ *	read device ready pin
+ */
+static int cmx270_device_ready(struct mtd_info *mtd)
+{
+	DRAIN_WB();
+
+	return (GPLR(GPIO_NAND_RB) & GPIO_bit(GPIO_NAND_RB));
+}
+
+/*
+ * Main initialization routine
+ */
+static int __devinit cmx270_init(void)
+{
+	struct nand_chip *this;
+	const char *part_type;
+	struct mtd_partition *mtd_parts;
+	int mtd_parts_nb = 0;
+	int ret;
+
+	/* Allocate memory for MTD device structure and private data */
+	cmx270_nand_mtd = kzalloc(sizeof(struct mtd_info) +
+				  sizeof(struct nand_chip),
+				  GFP_KERNEL);
+	if (!cmx270_nand_mtd) {
+		printk("Unable to allocate CM-X270 NAND MTD device structure.\n");
+		return -ENOMEM;
+	}
+
+	cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
+	if (!cmx270_nand_io) {
+		printk("Unable to ioremap NAND device\n");
+		ret = -EINVAL;
+		goto err1;
+	}
+
+	/* Get pointer to private data */
+	this = (struct nand_chip *)(&cmx270_nand_mtd[1]);
+
+	/* Link the private data with the MTD structure */
+	cmx270_nand_mtd->owner = THIS_MODULE;
+	cmx270_nand_mtd->priv = this;
+
+	/* insert callbacks */
+	this->IO_ADDR_R = cmx270_nand_io;
+	this->IO_ADDR_W = cmx270_nand_io;
+	this->cmd_ctrl = cmx270_hwcontrol;
+	this->dev_ready = cmx270_device_ready;
+
+	/* 15 us command delay time */
+	this->chip_delay = 20;
+	this->ecc.mode = NAND_ECC_SOFT;
+
+	/* read/write functions */
+	this->read_byte = cmx270_read_byte;
+	this->read_buf = cmx270_read_buf;
+	this->write_buf = cmx270_write_buf;
+	this->verify_buf = cmx270_verify_buf;
+
+	/* Scan to find existence of the device */
+	if (nand_scan (cmx270_nand_mtd, 1)) {
+		printk(KERN_NOTICE "No NAND device\n");
+		ret = -ENXIO;
+		goto err2;
+	}
+
+#ifdef CONFIG_MTD_CMDLINE_PARTS
+	mtd_parts_nb = parse_mtd_partitions(cmx270_nand_mtd, part_probes,
+					    &mtd_parts, 0);
+	if (mtd_parts_nb > 0)
+		part_type = "command line";
+	else
+		mtd_parts_nb = 0;
+#endif
+	if (!mtd_parts_nb) {
+		mtd_parts = partition_info;
+		mtd_parts_nb = NUM_PARTITIONS;
+		part_type = "static";
+	}
+
+	/* Register the partitions */
+	printk(KERN_NOTICE "Using %s partition definition\n", part_type);
+	ret = add_mtd_partitions(cmx270_nand_mtd, mtd_parts, mtd_parts_nb);
+	if (ret)
+		goto err2;
+
+	/* Return happy */
+	return 0;
+
+err2:
+	iounmap(cmx270_nand_io);
+err1:
+	kfree(cmx270_nand_mtd);
+
+	return ret;
+
+}
+module_init(cmx270_init);
+
+/*
+ * Clean up routine
+ */
+static void __devexit cmx270_cleanup(void)
+{
+	/* Release resources, unregister device */
+	nand_release(cmx270_nand_mtd);
+
+	iounmap(cmx270_nand_io);
+
+	/* Free the MTD device structure */
+	kfree (cmx270_nand_mtd);
+}
+module_exit(cmx270_cleanup);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
+MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module");

Re: [PATCH] cmx270-nand: Make CMDLINE_PARTS usable

[Raphael Assenat]

On Mon, Sep 25, 2006 at 09:07:55AM -0400, Raphael Assenat wrote:
> David Woodhouse wrote:
> > On Fri, 2006-09-22 at 10:15 -0400, Raphael Assenat wrote:
> > 
> >>Oh, sorry. My patch applies over the patch Mike Rapoport sent to the list on July 18
> >>([PATCH] [MTD] CM-x270 NAND flash support), which I thought was already accepted. Was 
> >>there anything wrong with it? Maybe you just missed it...
> >>
> >>I also sent a patch to the list on July 21 which added NAND flash support for the cm-x255 
> >>boards ([PATCH] Add support for NAND flash on cm-x255) but received no feedback. I can 
> >>resend it if you wish.
> > 
> > 
> > July and August weren't really a good time for sending stuff that you
> > expect me to pay attention to; sorry. Yes -- please retest and resend.
Here comes the resend.

This patch adds support for the NAND flash present on Compulab's cm-x255
boards. Since Compulab chose to discontinue cm-x255 support, I decided
to submit and support this driver myself.

Note: This is the driver I wrote as part of my Compulab kernel fork
project (see http://raph.people.8d.com/armcore_kernel.php). It is not
based on the driver Mike posted to the list.

Applies to 2.6.18

Signed-off-by: Raphael Assenat <raph@8d.com>

diff -Nru linux-2.6.18-rc2/drivers/mtd/nand/Kconfig linux-2.6.18-rc2-mtd/drivers/mtd/nand/Kconfig
--- linux-2.6.18-rc2/drivers/mtd/nand/Kconfig	2006-07-17 15:19:57.000000000 -0400
+++ linux-2.6.18-rc2-mtd/drivers/mtd/nand/Kconfig	2006-07-21 14:36:03.000000000 -0400
@@ -239,4 +239,11 @@
 	  The simulator may simulate various NAND flash chips for the
 	  MTD nand layer.
 
+config MTD_NAND_CM_X255
+	tristate "Support for NAND Flash on Compulab cm-x255"
+	depends on MTD_NAND && MACH_CM_X255
+	help
+	  This enables the driver for the NAND flash present
+	  on the cm-x255 board from Compulab.
+
 endmenu
diff -Nru linux-2.6.18-rc2/drivers/mtd/nand/Makefile linux-2.6.18-rc2-mtd/drivers/mtd/nand/Makefile
--- linux-2.6.18-rc2/drivers/mtd/nand/Makefile	2006-07-17 15:19:57.000000000 -0400
+++ linux-2.6.18-rc2-mtd/drivers/mtd/nand/Makefile	2006-07-21 14:36:31.000000000 -0400
@@ -22,5 +22,6 @@
 obj-$(CONFIG_MTD_NAND_NANDSIM)		+= nandsim.o
 obj-$(CONFIG_MTD_NAND_CS553X)		+= cs553x_nand.o
 obj-$(CONFIG_MTD_NAND_NDFC)		+= ndfc.o
+obj-$(CONFIG_MTD_NAND_CM_X255)		+= cm-x255.o
 
 nand-objs = nand_base.o nand_bbt.o
diff -Nru linux-2.6.18-rc2/drivers/mtd/nand/cm-x255.c linux-2.6.18-rc2-mtd/drivers/mtd/nand/cm-x255.c
--- linux-2.6.18-rc2/drivers/mtd/nand/cm-x255.c	1969-12-31 19:00:00.000000000 -0500
+++ linux-2.6.18-rc2-mtd/drivers/mtd/nand/cm-x255.c	2006-07-21 15:02:02.000000000 -0400
@@ -0,0 +1,183 @@
+/*
+ * drivers/mtd/nand/cm-x255.c
+ *
+ * Copyright (c) 2006, 8D Technologies inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Overview:
+ *   This is a device driver for the NAND flash device found on the
+ *   cm-x255 compulab sbc (formerly known as armcore).
+ *   
+ *  Changelog:
+ *  - April 2006, Raphael Assenat <raph@8d.com>:
+ * 	Creation of the driver.
+ * 	   
+ *  - Jul 18, 2006: Raphael Assenat <raph@8d.com>:
+ * 	Updates for 2.6.18
+ */
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/delay.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/arch/pxa-regs.h>
+#include <asm/arch/cm-x255.h>
+
+#define GPIO_NAND_CS	5
+#define GPIO_NAND_ALE	4
+#define GPIO_NAND_CLE	3
+#define GPIO_NAND_RB	10
+
+#define DRAIN_WRITE_BUFFER() do { \
+	asm volatile ("mcr p15, 0, r0, c7, c10, 4\n":::"r0"); \
+	dummy=*((volatile unsigned char*)UNCACHED_ADDR); \
+	} while(0)
+
+static struct mtd_info *armcore_mtd = NULL;
+static void __iomem *armcore_nand_io_base;
+static long armcore_nand_phys_base = 0x04000000;
+
+#define DEFAULT_NUM_PARTITIONS 1
+static int nr_partitions;
+static struct mtd_partition armcore_default_partition_info[] = {
+	{
+	.name = "rootfs",
+	.offset = 0,
+	.size = MTDPART_SIZ_FULL,
+	},
+};
+
+static void armcore_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, 
+						unsigned int ctrl)
+{
+	struct nand_chip *chip = mtd->priv;	
+	unsigned char dummy;
+
+	DRAIN_WRITE_BUFFER();
+
+	if (ctrl & NAND_CTRL_CHANGE)
+	{
+		if (ctrl & NAND_NCE) 
+			GPCR(GPIO_NAND_CS) = GPIO_bit(GPIO_NAND_CS); 
+		else
+			GPSR(GPIO_NAND_CS) = GPIO_bit(GPIO_NAND_CS); 
+
+		if (ctrl & NAND_CLE)
+			GPSR(GPIO_NAND_CLE) = GPIO_bit(GPIO_NAND_CLE); 
+		else
+			GPCR(GPIO_NAND_CLE) = GPIO_bit(GPIO_NAND_CLE); 
+
+		if (ctrl & NAND_ALE)
+			GPSR(GPIO_NAND_ALE) = GPIO_bit(GPIO_NAND_ALE); 
+		else
+			GPCR(GPIO_NAND_ALE) = GPIO_bit(GPIO_NAND_ALE); 
+
+	}
+	
+	DRAIN_WRITE_BUFFER();
+
+	if (cmd != NAND_CMD_NONE)
+		writeb(cmd, chip->IO_ADDR_W);
+}
+
+static int armcore_nand_device_ready(struct mtd_info *mtd)
+{
+	return GPLR(GPIO_NAND_RB) & GPIO_bit(GPIO_NAND_RB);
+}
+
+#ifdef CONFIG_MTD_PARTITIONS
+const char *part_probes[] = { "cmdlinepart", NULL };
+#endif
+
+int __init armcore_nand_init(void)
+{
+	struct nand_chip *this;
+	struct mtd_partition* armcore_partition_info;
+	int err = 0;
+
+	pxa_gpio_mode(GPIO_NAND_RB);
+	pxa_gpio_mode(GPIO_NAND_CS | GPIO_OUT | GPIO_DFLT_HIGH);
+	pxa_gpio_mode(GPIO_NAND_ALE | GPIO_OUT | GPIO_DFLT_LOW);
+	pxa_gpio_mode(GPIO_NAND_CLE | GPIO_OUT | GPIO_DFLT_LOW);
+	
+	/* Allocate memory for MTD device structure and private data */	
+	armcore_mtd = kmalloc(	sizeof(struct mtd_info) + 
+				sizeof(struct nand_chip), 
+						GFP_KERNEL);
+	if (!armcore_mtd) {
+		printk(KERN_WARNING 
+		"Unable to allocate cm-x255 nand mtd device structure.\n");
+		err = -ENOMEM;
+		goto out;
+	}
+
+	/* map physical adress */
+	armcore_nand_io_base = ioremap(armcore_nand_phys_base, 0x100);
+	if (!armcore_nand_io_base) {
+		printk(KERN_WARNING "ioremap for cm-x255 NAND chip failed\n");
+		err = -EIO;
+		goto out_mtd;
+	}
+
+	/* Get pointer to private data */
+	this = (struct nand_chip *) (&armcore_mtd[1]);
+
+	/* Initialize structures */
+	memset((char *) armcore_mtd, 0, sizeof(struct mtd_info));
+	memset((char *) this, 0, sizeof(struct nand_chip));
+
+	/* Link the private data with the MTD structure */
+	armcore_mtd->priv = this;
+
+	this->IO_ADDR_R = armcore_nand_io_base;	
+	this->IO_ADDR_W = armcore_nand_io_base;	
+	this->cmd_ctrl = armcore_nand_cmd_ctrl;
+	this->dev_ready = armcore_nand_device_ready;
+	this->chip_delay = 15;
+	this->ecc.mode = NAND_ECC_SOFT;
+
+	/* Scan to find existance of the device */
+	if (nand_scan(armcore_mtd, 1)) {
+		printk(KERN_WARNING 
+			"nand_scan() failed to scan cm-x255 nand flash\n");
+		err = -ENXIO;
+		goto out_ior;
+	}
+
+	/* Register the partitions */
+	armcore_mtd->name = "armcore-nand";
+	nr_partitions = parse_mtd_partitions(armcore_mtd, part_probes,
+						&armcore_partition_info, 0);
+	if (nr_partitions <= 0) {
+		nr_partitions = DEFAULT_NUM_PARTITIONS;
+		armcore_partition_info = armcore_default_partition_info;
+	}
+
+	add_mtd_partitions(armcore_mtd, armcore_partition_info, nr_partitions);	
+	
+	goto out;
+
+out_ior:
+	iounmap((void*) armcore_nand_io_base);
+out_mtd:
+	kfree(armcore_mtd);
+out:
+	return err;
+}
+module_init(armcore_nand_init);
+
+static void __exit armcore_nand_cleanup(void)
+{
+	nand_release(armcore_mtd);
+	iounmap((void*)armcore_nand_io_base);
+	kfree(armcore_mtd);
+}
+module_exit(armcore_nand_cleanup);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Raphael Assenat <raph@8d.com>");
+MODULE_DESCRIPTION("NAND flash driver for cm-x255 boards");