Adding .24 support for olpc

kernel compiles fine, but graphic support is broken

to test new kernel version, change 
target/linux/olpc/Makefile
from .23.16 to .24



git-svn-id: svn://svn.openwrt.org/openwrt/trunk@10493 3c298f89-4303-0410-b956-a3cf2f4a3e73

3 files changed, 871 insertions, 0 deletions

diff --git a/target/linux/olpc/files-2.6.23/drivers/mtd/mtdcore.h b/target/linux/olpc/files-2.6.23/drivers/mtd/mtdcore.h
new file mode 100644
index 0000000000..a33251f4b8
--- /dev/null
+++ b/target/linux/olpc/files-2.6.23/drivers/mtd/mtdcore.h
@@ -0,0 +1,11 @@
+/* linux/drivers/mtd/mtdcore.h
+ *
+ * Header file for driver private mtdcore exports
+ *
+ */
+
+/* These are exported solely for the purpose of mtd_blkdevs.c. You
+   should not use them for _anything_ else */
+
+extern struct mutex mtd_table_mutex;
+extern struct mtd_info *mtd_table[MAX_MTD_DEVICES];
diff --git a/target/linux/olpc/files-2.6.23/drivers/mtd/mtdoops.c b/target/linux/olpc/files-2.6.23/drivers/mtd/mtdoops.c
new file mode 100644
index 0000000000..cfc28ab4a3
--- /dev/null
+++ b/target/linux/olpc/files-2.6.23/drivers/mtd/mtdoops.c
@@ -0,0 +1,365 @@
+/*
+ * MTD Oops/Panic logger
+ *
+ * Copyright (C) 2007 Nokia Corporation. All rights reserved.
+ *
+ * Author: Richard Purdie <rpurdie@openedhand.com>
+ *
+ * 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.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/console.h>
+#include <linux/vmalloc.h>
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/mtd/mtd.h>
+
+#define OOPS_PAGE_SIZE 4096
+
+static struct mtdoops_context {
+	int mtd_index;
+	struct work_struct work;
+	struct mtd_info *mtd;
+	int oops_pages;
+	int nextpage;
+	int nextcount;
+
+	void *oops_buf;
+	int ready;
+	int writecount;
+} oops_cxt;
+
+static void mtdoops_erase_callback(struct erase_info *done)
+{
+	wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv;
+	wake_up(wait_q);
+}
+
+static int mtdoops_erase_block(struct mtd_info *mtd, int offset)
+{
+	struct erase_info erase;
+	DECLARE_WAITQUEUE(wait, current);
+	wait_queue_head_t wait_q;
+	int ret;
+
+	init_waitqueue_head(&wait_q);
+	erase.mtd = mtd;
+	erase.callback = mtdoops_erase_callback;
+	erase.addr = offset;
+	if (mtd->erasesize < OOPS_PAGE_SIZE)
+		erase.len = OOPS_PAGE_SIZE;
+	else
+		erase.len = mtd->erasesize;
+	erase.priv = (u_long)&wait_q;
+
+	set_current_state(TASK_INTERRUPTIBLE);
+	add_wait_queue(&wait_q, &wait);
+
+	ret = mtd->erase(mtd, &erase);
+	if (ret) {
+		set_current_state(TASK_RUNNING);
+		remove_wait_queue(&wait_q, &wait);
+		printk (KERN_WARNING "mtdoops: erase of region [0x%x, 0x%x] "
+				     "on \"%s\" failed\n",
+			erase.addr, erase.len, mtd->name);
+		return ret;
+	}
+
+	schedule();  /* Wait for erase to finish. */
+	remove_wait_queue(&wait_q, &wait);
+
+	return 0;
+}
+
+static int mtdoops_inc_counter(struct mtdoops_context *cxt)
+{
+	struct mtd_info *mtd = cxt->mtd;
+	size_t retlen;
+	u32 count;
+	int ret;
+
+	cxt->nextpage++;
+	if (cxt->nextpage > cxt->oops_pages)
+		cxt->nextpage = 0;
+	cxt->nextcount++;
+	if (cxt->nextcount == 0xffffffff)
+		cxt->nextcount = 0;
+
+	ret = mtd->read(mtd, cxt->nextpage * OOPS_PAGE_SIZE, 4,
+			&retlen, (u_char *) &count);
+	if ((retlen != 4) || (ret < 0)) {
+		printk(KERN_ERR "mtdoops: Read failure at %d (%d of 4 read)"
+				", err %d.\n", cxt->nextpage * OOPS_PAGE_SIZE,
+				retlen, ret);
+		return 1;
+	}
+
+	/* See if we need to erase the next block */
+	if (count != 0xffffffff)
+		return 1;
+
+	printk(KERN_DEBUG "mtdoops: Ready %d, %d (no erase)\n",
+			cxt->nextpage, cxt->nextcount);
+	cxt->ready = 1;
+	return 0;
+}
+
+static void mtdoops_prepare(struct mtdoops_context *cxt)
+{
+	struct mtd_info *mtd = cxt->mtd;
+	int i = 0, j, ret, mod;
+
+	/* We were unregistered */
+	if (!mtd)
+		return;
+
+	mod = (cxt->nextpage * OOPS_PAGE_SIZE) % mtd->erasesize;
+	if (mod != 0) {
+		cxt->nextpage = cxt->nextpage + ((mtd->erasesize - mod) / OOPS_PAGE_SIZE);
+		if (cxt->nextpage > cxt->oops_pages)
+			cxt->nextpage = 0;
+	}
+
+	while (mtd->block_isbad &&
+			mtd->block_isbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE)) {
+badblock:
+		printk(KERN_WARNING "mtdoops: Bad block at %08x\n",
+				cxt->nextpage * OOPS_PAGE_SIZE);
+		i++;
+		cxt->nextpage = cxt->nextpage + (mtd->erasesize / OOPS_PAGE_SIZE);
+		if (cxt->nextpage > cxt->oops_pages)
+			cxt->nextpage = 0;
+		if (i == (cxt->oops_pages / (mtd->erasesize / OOPS_PAGE_SIZE))) {
+			printk(KERN_ERR "mtdoops: All blocks bad!\n");
+			return;
+		}
+	}
+
+	for (j = 0, ret = -1; (j < 3) && (ret < 0); j++)
+		ret = mtdoops_erase_block(mtd, cxt->nextpage * OOPS_PAGE_SIZE);
+
+	if (ret < 0) {
+		if (mtd->block_markbad)
+			mtd->block_markbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE);
+		goto badblock;
+	}
+
+	printk(KERN_DEBUG "mtdoops: Ready %d, %d \n", cxt->nextpage, cxt->nextcount);
+
+	cxt->ready = 1;
+}
+
+static void mtdoops_workfunc(struct work_struct *work)
+{
+	struct mtdoops_context *cxt =
+			container_of(work, struct mtdoops_context, work);
+
+	mtdoops_prepare(cxt);
+}
+
+static int find_next_position(struct mtdoops_context *cxt)
+{
+	struct mtd_info *mtd = cxt->mtd;
+	int page, maxpos = 0;
+	u32 count, maxcount = 0xffffffff;
+	size_t retlen;
+
+	for (page = 0; page < cxt->oops_pages; page++) {
+		mtd->read(mtd, page * OOPS_PAGE_SIZE, 4, &retlen, (u_char *) &count);
+		if (count == 0xffffffff)
+			continue;
+		if (maxcount == 0xffffffff) {
+			maxcount = count;
+			maxpos = page;
+		} else if ((count < 0x40000000) && (maxcount > 0xc0000000)) {
+			maxcount = count;
+			maxpos = page;
+		} else if ((count > maxcount) && (count < 0xc0000000)) {
+			maxcount = count;
+			maxpos = page;
+		} else if ((count > maxcount) && (count > 0xc0000000)
+					&& (maxcount > 0x80000000)) {
+			maxcount = count;
+			maxpos = page;
+		}
+	}
+	if (maxcount == 0xffffffff) {
+		cxt->nextpage = 0;
+		cxt->nextcount = 1;
+		cxt->ready = 1;
+		printk(KERN_DEBUG "mtdoops: Ready %d, %d (first init)\n",
+				cxt->nextpage, cxt->nextcount);
+		return 0;
+	}
+
+	cxt->nextpage = maxpos;
+	cxt->nextcount = maxcount;
+
+	return mtdoops_inc_counter(cxt);
+}
+
+
+static void mtdoops_notify_add(struct mtd_info *mtd)
+{
+	struct mtdoops_context *cxt = &oops_cxt;
+	int ret;
+
+	if ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0)
+		return;
+
+	if (mtd->size < (mtd->erasesize * 2)) {
+		printk(KERN_ERR "MTD partition %d not big enough for mtdoops\n",
+				mtd->index);
+		return;
+	}
+
+	cxt->mtd = mtd;
+	cxt->oops_pages = mtd->size / OOPS_PAGE_SIZE;
+
+	ret = find_next_position(cxt);
+	if (ret == 1)
+		mtdoops_prepare(cxt);
+
+	printk(KERN_DEBUG "mtdoops: Attached to MTD device %d\n", mtd->index);
+}
+
+static void mtdoops_notify_remove(struct mtd_info *mtd)
+{
+	struct mtdoops_context *cxt = &oops_cxt;
+
+	if ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0)
+		return;
+
+	cxt->mtd = NULL;
+	flush_scheduled_work();
+}
+
+
+static void
+mtdoops_console_write(struct console *co, const char *s, unsigned int count)
+{
+	struct mtdoops_context *cxt = co->data;
+	struct mtd_info *mtd = cxt->mtd;
+	int i, ret;
+
+	if (!cxt->ready || !mtd)
+		return;
+
+	if (!oops_in_progress && cxt->writecount != 0) {
+		size_t retlen;
+		if (cxt->writecount < OOPS_PAGE_SIZE)
+			memset(cxt->oops_buf + cxt->writecount, 0xff,
+					OOPS_PAGE_SIZE - cxt->writecount);
+
+		ret = mtd->write(mtd, cxt->nextpage * OOPS_PAGE_SIZE,
+					OOPS_PAGE_SIZE, &retlen, cxt->oops_buf);
+		cxt->ready = 0;
+		cxt->writecount = 0;
+
+		if ((retlen != OOPS_PAGE_SIZE) || (ret < 0))
+			printk(KERN_ERR "mtdoops: Write failure at %d (%d of %d"
+				" written), err %d.\n",
+				cxt->nextpage * OOPS_PAGE_SIZE, retlen,
+				OOPS_PAGE_SIZE, ret);
+
+		ret = mtdoops_inc_counter(cxt);
+		if (ret == 1)
+			schedule_work(&cxt->work);
+	}
+
+	if (!oops_in_progress)
+		return;
+
+	if (cxt->writecount == 0) {
+		u32 *stamp = cxt->oops_buf;
+		*stamp = cxt->nextcount;
+		cxt->writecount = 4;
+	}
+
+	if ((count + cxt->writecount) > OOPS_PAGE_SIZE)
+		count = OOPS_PAGE_SIZE - cxt->writecount;
+
+	for (i = 0; i < count; i++, s++)
+		*((char *)(cxt->oops_buf) + cxt->writecount + i) = *s;
+
+	cxt->writecount = cxt->writecount + count;
+}
+
+static int __init mtdoops_console_setup(struct console *co, char *options)
+{
+	struct mtdoops_context *cxt = co->data;
+
+	if (cxt->mtd_index != -1)
+		return -EBUSY;
+	if (co->index == -1)
+		return -EINVAL;
+
+	cxt->mtd_index = co->index;
+	return 0;
+}
+
+static struct mtd_notifier mtdoops_notifier = {
+	.add	= mtdoops_notify_add,
+	.remove	= mtdoops_notify_remove,
+};
+
+static struct console mtdoops_console = {
+	.name		= "ttyMTD",
+	.write		= mtdoops_console_write,
+	.setup		= mtdoops_console_setup,
+	.flags		= CON_PRINTBUFFER,
+	.index		= -1,
+	.data		= &oops_cxt,
+};
+
+static int __init mtdoops_console_init(void)
+{
+	struct mtdoops_context *cxt = &oops_cxt;
+
+	cxt->mtd_index = -1;
+	cxt->oops_buf = vmalloc(OOPS_PAGE_SIZE);
+
+	if (!cxt->oops_buf) {
+		printk(KERN_ERR "Failed to allocate oops buffer workspace\n");
+		return -ENOMEM;
+	}
+
+	INIT_WORK(&cxt->work, mtdoops_workfunc);
+
+	register_console(&mtdoops_console);
+	register_mtd_user(&mtdoops_notifier);
+	return 0;
+}
+
+static void __exit mtdoops_console_exit(void)
+{
+	struct mtdoops_context *cxt = &oops_cxt;
+
+	unregister_mtd_user(&mtdoops_notifier);
+	unregister_console(&mtdoops_console);
+	vfree(cxt->oops_buf);
+}
+
+
+subsys_initcall(mtdoops_console_init);
+module_exit(mtdoops_console_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
+MODULE_DESCRIPTION("MTD Oops/Panic console logger/driver");
diff --git a/target/linux/olpc/files-2.6.23/drivers/mtd/onenand/onenand_sim.c b/target/linux/olpc/files-2.6.23/drivers/mtd/onenand/onenand_sim.c
new file mode 100644
index 0000000000..b80667309b
--- /dev/null
+++ b/target/linux/olpc/files-2.6.23/drivers/mtd/onenand/onenand_sim.c
@@ -0,0 +1,495 @@
+/*
+ *  linux/drivers/mtd/onenand/onenand_sim.c
+ *
+ *  The OneNAND simulator
+ *
+ *  Copyright © 2005-2007 Samsung Electronics
+ *  Kyungmin Park <kyungmin.park@samsung.com>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/vmalloc.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/onenand.h>
+
+#include <linux/io.h>
+
+#ifndef CONFIG_ONENAND_SIM_MANUFACTURER
+#define CONFIG_ONENAND_SIM_MANUFACTURER         0xec
+#endif
+#ifndef CONFIG_ONENAND_SIM_DEVICE_ID
+#define CONFIG_ONENAND_SIM_DEVICE_ID            0x04
+#endif
+#ifndef CONFIG_ONENAND_SIM_VERSION_ID
+#define CONFIG_ONENAND_SIM_VERSION_ID           0x1e
+#endif
+
+static int manuf_id	= CONFIG_ONENAND_SIM_MANUFACTURER;
+static int device_id	= CONFIG_ONENAND_SIM_DEVICE_ID;
+static int version_id	= CONFIG_ONENAND_SIM_VERSION_ID;
+
+struct onenand_flash {
+	void __iomem *base;
+	void __iomem *data;
+};
+
+#define ONENAND_CORE(flash)		(flash->data)
+#define ONENAND_CORE_SPARE(flash, this, offset)				\
+	((flash->data) + (this->chipsize) + (offset >> 5))
+
+#define ONENAND_MAIN_AREA(this, offset)					\
+	(this->base + ONENAND_DATARAM + offset)
+
+#define ONENAND_SPARE_AREA(this, offset)				\
+	(this->base + ONENAND_SPARERAM + offset)
+
+#define ONENAND_GET_WP_STATUS(this)					\
+	(readw(this->base + ONENAND_REG_WP_STATUS))
+
+#define ONENAND_SET_WP_STATUS(v, this)					\
+	(writew(v, this->base + ONENAND_REG_WP_STATUS))
+
+/* It has all 0xff chars */
+#define MAX_ONENAND_PAGESIZE		(2048 + 64)
+static unsigned char *ffchars;
+
+static struct mtd_partition os_partitions[] = {
+	{
+		.name		= "OneNAND simulator partition",
+		.offset		= 0,
+		.size		= MTDPART_SIZ_FULL,
+	},
+};
+
+/*
+ * OneNAND simulator mtd
+ */
+struct onenand_info {
+	struct mtd_info		mtd;
+	struct mtd_partition	*parts;
+	struct onenand_chip	onenand;
+	struct onenand_flash	flash;
+};
+
+struct onenand_info *info;
+
+#define DPRINTK(format, args...)					\
+do {									\
+	printk(KERN_DEBUG "%s[%d]: " format "\n", __func__,		\
+			   __LINE__, ##args);				\
+} while (0)
+
+/**
+ * onenand_lock_handle - Handle Lock scheme
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ *
+ * Send lock command to OneNAND device.
+ * The lock scheme is depends on chip type.
+ */
+static void onenand_lock_handle(struct onenand_chip *this, int cmd)
+{
+	int block_lock_scheme;
+	int status;
+
+	status = ONENAND_GET_WP_STATUS(this);
+	block_lock_scheme = !(this->options & ONENAND_HAS_CONT_LOCK);
+
+	switch (cmd) {
+	case ONENAND_CMD_UNLOCK:
+		if (block_lock_scheme)
+			ONENAND_SET_WP_STATUS(ONENAND_WP_US, this);
+		else
+			ONENAND_SET_WP_STATUS(status | ONENAND_WP_US, this);
+		break;
+
+	case ONENAND_CMD_LOCK:
+		if (block_lock_scheme)
+			ONENAND_SET_WP_STATUS(ONENAND_WP_LS, this);
+		else
+			ONENAND_SET_WP_STATUS(status | ONENAND_WP_LS, this);
+		break;
+
+	case ONENAND_CMD_LOCK_TIGHT:
+		if (block_lock_scheme)
+			ONENAND_SET_WP_STATUS(ONENAND_WP_LTS, this);
+		else
+			ONENAND_SET_WP_STATUS(status | ONENAND_WP_LTS, this);
+		break;
+
+	default:
+		break;
+	}
+}
+
+/**
+ * onenand_bootram_handle - Handle BootRAM area
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ *
+ * Emulate BootRAM area. It is possible to do basic operation using BootRAM.
+ */
+static void onenand_bootram_handle(struct onenand_chip *this, int cmd)
+{
+	switch (cmd) {
+	case ONENAND_CMD_READID:
+		writew(manuf_id, this->base);
+		writew(device_id, this->base + 2);
+		writew(version_id, this->base + 4);
+		break;
+
+	default:
+		/* REVIST: Handle other commands */
+		break;
+	}
+}
+
+/**
+ * onenand_update_interrupt - Set interrupt register
+ * @param this         OneNAND device structure
+ * @param cmd          The command to be sent
+ *
+ * Update interrupt register. The status is depends on command.
+ */
+static void onenand_update_interrupt(struct onenand_chip *this, int cmd)
+{
+	int interrupt = ONENAND_INT_MASTER;
+
+	switch (cmd) {
+	case ONENAND_CMD_READ:
+	case ONENAND_CMD_READOOB:
+		interrupt |= ONENAND_INT_READ;
+		break;
+
+	case ONENAND_CMD_PROG:
+	case ONENAND_CMD_PROGOOB:
+		interrupt |= ONENAND_INT_WRITE;
+		break;
+
+	case ONENAND_CMD_ERASE:
+		interrupt |= ONENAND_INT_ERASE;
+		break;
+
+	case ONENAND_CMD_RESET:
+		interrupt |= ONENAND_INT_RESET;
+		break;
+
+	default:
+		break;
+	}
+
+	writew(interrupt, this->base + ONENAND_REG_INTERRUPT);
+}
+
+/**
+ * onenand_check_overwrite - Check over-write if happend
+ * @param dest		The destination pointer
+ * @param src		The source pointer
+ * @param count		The length to be check
+ * @return		0 on same, otherwise 1
+ *
+ * Compare the source with destination
+ */
+static int onenand_check_overwrite(void *dest, void *src, size_t count)
+{
+	unsigned int *s = (unsigned int *) src;
+	unsigned int *d = (unsigned int *) dest;
+	int i;
+
+	count >>= 2;
+	for (i = 0; i < count; i++)
+		if ((*s++ ^ *d++) != 0)
+			return 1;
+
+	return 0;
+}
+
+/**
+ * onenand_data_handle - Handle OneNAND Core and DataRAM
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ * @param dataram	Which dataram used
+ * @param offset	The offset to OneNAND Core
+ *
+ * Copy data from OneNAND Core to DataRAM (read)
+ * Copy data from DataRAM to OneNAND Core (write)
+ * Erase the OneNAND Core (erase)
+ */
+static void onenand_data_handle(struct onenand_chip *this, int cmd,
+				int dataram, unsigned int offset)
+{
+	struct mtd_info *mtd = &info->mtd;
+	struct onenand_flash *flash = this->priv;
+	int main_offset, spare_offset;
+	void __iomem *src;
+	void __iomem *dest;
+	unsigned int i;
+
+	if (dataram) {
+		main_offset = mtd->writesize;
+		spare_offset = mtd->oobsize;
+	} else {
+		main_offset = 0;
+		spare_offset = 0;
+	}
+
+	switch (cmd) {
+	case ONENAND_CMD_READ:
+		src = ONENAND_CORE(flash) + offset;
+		dest = ONENAND_MAIN_AREA(this, main_offset);
+		memcpy(dest, src, mtd->writesize);
+		/* Fall through */
+
+	case ONENAND_CMD_READOOB:
+		src = ONENAND_CORE_SPARE(flash, this, offset);
+		dest = ONENAND_SPARE_AREA(this, spare_offset);
+		memcpy(dest, src, mtd->oobsize);
+		break;
+
+	case ONENAND_CMD_PROG:
+		src = ONENAND_MAIN_AREA(this, main_offset);
+		dest = ONENAND_CORE(flash) + offset;
+		/* To handle partial write */
+		for (i = 0; i < (1 << mtd->subpage_sft); i++) {
+			int off = i * this->subpagesize;
+			if (!memcmp(src + off, ffchars, this->subpagesize))
+				continue;
+			if (memcmp(dest + off, ffchars, this->subpagesize) &&
+			    onenand_check_overwrite(dest + off, src + off, this->subpagesize))
+				printk(KERN_ERR "over-write happend at 0x%08x\n", offset);
+			memcpy(dest + off, src + off, this->subpagesize);
+		}
+		/* Fall through */
+
+	case ONENAND_CMD_PROGOOB:
+		src = ONENAND_SPARE_AREA(this, spare_offset);
+		/* Check all data is 0xff chars */
+		if (!memcmp(src, ffchars, mtd->oobsize))
+			break;
+
+		dest = ONENAND_CORE_SPARE(flash, this, offset);
+		if (memcmp(dest, ffchars, mtd->oobsize) &&
+		    onenand_check_overwrite(dest, src, mtd->oobsize))
+			printk(KERN_ERR "OOB: over-write happend at 0x%08x\n",
+			       offset);
+		memcpy(dest, src, mtd->oobsize);
+		break;
+
+	case ONENAND_CMD_ERASE:
+		memset(ONENAND_CORE(flash) + offset, 0xff, mtd->erasesize);
+		memset(ONENAND_CORE_SPARE(flash, this, offset), 0xff,
+		       (mtd->erasesize >> 5));
+		break;
+
+	default:
+		break;
+	}
+}
+
+/**
+ * onenand_command_handle - Handle command
+ * @param this		OneNAND device structure
+ * @param cmd		The command to be sent
+ *
+ * Emulate OneNAND command.
+ */
+static void onenand_command_handle(struct onenand_chip *this, int cmd)
+{
+	unsigned long offset = 0;
+	int block = -1, page = -1, bufferram = -1;
+	int dataram = 0;
+
+	switch (cmd) {
+	case ONENAND_CMD_UNLOCK:
+	case ONENAND_CMD_LOCK:
+	case ONENAND_CMD_LOCK_TIGHT:
+	case ONENAND_CMD_UNLOCK_ALL:
+		onenand_lock_handle(this, cmd);
+		break;
+
+	case ONENAND_CMD_BUFFERRAM:
+		/* Do nothing */
+		return;
+
+	default:
+		block = (int) readw(this->base + ONENAND_REG_START_ADDRESS1);
+		if (block & (1 << ONENAND_DDP_SHIFT)) {
+			block &= ~(1 << ONENAND_DDP_SHIFT);
+			/* The half of chip block */
+			block += this->chipsize >> (this->erase_shift + 1);
+		}
+		if (cmd == ONENAND_CMD_ERASE)
+			break;
+
+		page = (int) readw(this->base + ONENAND_REG_START_ADDRESS8);
+		page = (page >> ONENAND_FPA_SHIFT);
+		bufferram = (int) readw(this->base + ONENAND_REG_START_BUFFER);
+		bufferram >>= ONENAND_BSA_SHIFT;
+		bufferram &= ONENAND_BSA_DATARAM1;
+		dataram = (bufferram == ONENAND_BSA_DATARAM1) ? 1 : 0;
+		break;
+	}
+
+	if (block != -1)
+		offset += block << this->erase_shift;
+
+	if (page != -1)
+		offset += page << this->page_shift;
+
+	onenand_data_handle(this, cmd, dataram, offset);
+
+	onenand_update_interrupt(this, cmd);
+}
+
+/**
+ * onenand_writew - [OneNAND Interface] Emulate write operation
+ * @param value		value to write
+ * @param addr		address to write
+ *
+ * Write OneNAND register with value
+ */
+static void onenand_writew(unsigned short value, void __iomem * addr)
+{
+	struct onenand_chip *this = info->mtd.priv;
+
+	/* BootRAM handling */
+	if (addr < this->base + ONENAND_DATARAM) {
+		onenand_bootram_handle(this, value);
+		return;
+	}
+	/* Command handling */
+	if (addr == this->base + ONENAND_REG_COMMAND)
+		onenand_command_handle(this, value);
+
+	writew(value, addr);
+}
+
+/**
+ * flash_init - Initialize OneNAND simulator
+ * @param flash		OneNAND simulaotr data strucutres
+ *
+ * Initialize OneNAND simulator.
+ */
+static int __init flash_init(struct onenand_flash *flash)
+{
+	int density, size;
+	int buffer_size;
+
+	flash->base = kzalloc(131072, GFP_KERNEL);
+	if (!flash->base) {
+		printk(KERN_ERR "Unable to allocate base address.\n");
+		return -ENOMEM;
+	}
+
+	density = device_id >> ONENAND_DEVICE_DENSITY_SHIFT;
+	size = ((16 << 20) << density);
+
+	ONENAND_CORE(flash) = vmalloc(size + (size >> 5));
+	if (!ONENAND_CORE(flash)) {
+		printk(KERN_ERR "Unable to allocate nand core address.\n");
+		kfree(flash->base);
+		return -ENOMEM;
+	}
+
+	memset(ONENAND_CORE(flash), 0xff, size + (size >> 5));
+
+	/* Setup registers */
+	writew(manuf_id, flash->base + ONENAND_REG_MANUFACTURER_ID);
+	writew(device_id, flash->base + ONENAND_REG_DEVICE_ID);
+	writew(version_id, flash->base + ONENAND_REG_VERSION_ID);
+
+	if (density < 2)
+		buffer_size = 0x0400;	/* 1KiB page */
+	else
+		buffer_size = 0x0800;	/* 2KiB page */
+	writew(buffer_size, flash->base + ONENAND_REG_DATA_BUFFER_SIZE);
+
+	return 0;
+}
+
+/**
+ * flash_exit - Clean up OneNAND simulator
+ * @param flash		OneNAND simulaotr data strucutres
+ *
+ * Clean up OneNAND simulator.
+ */
+static void flash_exit(struct onenand_flash *flash)
+{
+	vfree(ONENAND_CORE(flash));
+	kfree(flash->base);
+	kfree(flash);
+}
+
+static int __init onenand_sim_init(void)
+{
+	/* Allocate all 0xff chars pointer */
+	ffchars = kmalloc(MAX_ONENAND_PAGESIZE, GFP_KERNEL);
+	if (!ffchars) {
+		printk(KERN_ERR "Unable to allocate ff chars.\n");
+		return -ENOMEM;
+	}
+	memset(ffchars, 0xff, MAX_ONENAND_PAGESIZE);
+
+	/* Allocate OneNAND simulator mtd pointer */
+	info = kzalloc(sizeof(struct onenand_info), GFP_KERNEL);
+	if (!info) {
+		printk(KERN_ERR "Unable to allocate core structures.\n");
+		kfree(ffchars);
+		return -ENOMEM;
+	}
+
+	/* Override write_word function */
+	info->onenand.write_word = onenand_writew;
+
+	if (flash_init(&info->flash)) {
+		printk(KERN_ERR "Unable to allocat flash.\n");
+		kfree(ffchars);
+		kfree(info);
+		return -ENOMEM;
+	}
+
+	info->parts = os_partitions;
+
+	info->onenand.base = info->flash.base;
+	info->onenand.priv = &info->flash;
+
+	info->mtd.name = "OneNAND simulator";
+	info->mtd.priv = &info->onenand;
+	info->mtd.owner = THIS_MODULE;
+
+	if (onenand_scan(&info->mtd, 1)) {
+		flash_exit(&info->flash);
+		kfree(ffchars);
+		kfree(info);
+		return -ENXIO;
+	}
+
+	add_mtd_partitions(&info->mtd, info->parts, ARRAY_SIZE(os_partitions));
+
+	return 0;
+}
+
+static void __exit onenand_sim_exit(void)
+{
+	struct onenand_chip *this = info->mtd.priv;
+	struct onenand_flash *flash = this->priv;
+
+	onenand_release(&info->mtd);
+	flash_exit(flash);
+	kfree(ffchars);
+	kfree(info);
+}
+
+module_init(onenand_sim_init);
+module_exit(onenand_sim_exit);
+
+MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>");
+MODULE_DESCRIPTION("The OneNAND flash simulator");
+MODULE_LICENSE("GPL");