Patchwork [ANNOUNCE,MTD] Flex-OneNAND MTD Driver available.

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Submitter Rohit
Date Nov. 7, 2008, 2:26 p.m.
Message ID <49145004.9010202@samsung.com>
Download mbox | patch
Permalink /patch/7718/
State New
Headers show

Comments

Rohit - Nov. 7, 2008, 2:26 p.m.
Hi Adrian,

Adrian Hunter wrote:
>> +static unsigned flexonenand_get_block(struct onenand_chip *this, loff_t addr,
>> +			   unsigned *isblkslc)
>> +{
>> +	unsigned boundary, blk, die = 0;
>> +
>> +	if (unlikely(this->chipsize == 0))
>> +		/* We have been called by flexonenand_get_boundary.
>> +		 * addr contains die index in this case.
>> +		 */
> 
> This seems to affect only FLEXONENAND_CMD_PI_ACCESS and ONENAND_CMD_READ.
> onenand_command() can be amended to handle FLEXONENAND_CMD_PI_ACCESS,
> and a fake command could be added for the ONENAND_CMD_READ case,
> then this kludge goes away.

Thanks for the suggestion. Fixed.

>> +	/* check if we failed due to uncorrectable error */
>> +	if (status != (-EBADMSG) && status != (ONENAND_BBT_READ_ECC_ERROR))
> 
> Please omit the unnecessary parentheses around -EBADMSG and ONENAND_BBT_READ_ECC_ERROR.

Fixed.

>> +	/* We are attempting to reread, so decrement stats.failed
>> +	 * which was incremented by onenand_wait due to read failure
>> +	 */
>> +	printk(KERN_INFO "Attempting to recover from uncorrectable read\n");
> 
> Message with no source. How about: "onenand_recover_lsb: Attempting to recover from uncorrectable read\n"

Fixed.

>> +	/* Do not allow reads past end of device */
>> +	if ((from + len) > mtd->size) {
> 
> Please omit unnecessary parenthesis

Fixed.

>> +			ret = this->wait(mtd, FL_READING);
>> +			ret = unlikely(ret) ? onenand_recover_lsb(mtd, from, ret) : ret;
> 
> That is unusual syntax.  The following is much more common:

Fixed

>> +	for (die = 0; die < this->dies; die++) {
>> +		this->command(mtd, FLEXONENAND_CMD_PI_ACCESS, die, 0);
>> +		this->wait(mtd, FL_SYNCING);
> 
> Why is the error return not checked?
> 
>> +
>> +		this->command(mtd, ONENAND_CMD_READ, die, 0);
>> +		ret = this->wait(mtd, FL_READING);
> 
> Why is the error return not checked?
> 
>> +
>> +		bdry = this->read_word(this->base + ONENAND_DATARAM);
>> +		locked = bdry >> FLEXONENAND_PI_UNLOCK_SHIFT;
>> +		locked = (locked == 0x3) ? 0 : 1;
>> +		this->boundary[die] = bdry & FLEXONENAND_PI_MASK;
>> +		this->boundary_locked[die] = locked;
>> +		this->command(mtd, ONENAND_CMD_RESET, 0, 0);
>> +		ret = this->wait(mtd, FL_RESETING);
> 
> Why is the error return not checked?

As per datasheet PI_ACCESS, PI_UPDATE, PI_READ and RESET always succeed.
PI_ERASE and PI_WRITE can fail. Added error check for PI_ERASE.

>> +		printk(KERN_ERR "Failed PI update for Die %d\n", die);
>> +	else
>> +		printk(KERN_INFO "Done\n");
>> +out:
>> +	this->write_word(ONENAND_CMD_RESET, this->base + ONENAND_REG_COMMAND);
>> +	this->wait(mtd, FL_RESETING);
>> +	if (!ret)
>> +		/* Recalculate device size on boundary change*/
>> +		flexonenand_get_size(mtd);
>> +	return ret;
>> +}
> 
> The functions above often use 'printk()' but do not identify the message source.
> I suggest adding the function name e.g. "flexonenand_set_boundary: blah blah"
> 
> Also using line continuations for strings results in the string
> containing unwanted tabs and spaces. e.g.
> 
> 				"Invalid boundary value.\
> 					 Boundary not changed.\n"
> 
> results in:
> 
> "Invalid boundary value.					 Boundary not changed.\n"
> 
> Instead you can just close and reopen the string e.g.
> 				"Invalid boundary value."
> 					" Boundary not changed.\n"

Fixed

>> +	if (FLEXONENAND(this)) {
>> +		int boundary[] =
>> +			{FLEXONENAND_DIE0_BOUNDARY, FLEXONENAND_DIE1_BOUNDARY};
>> +		int lock[] =
>> +			{FLEXONENAND_DIE0_ISLOCKED, FLEXONENAND_DIE1_ISLOCKED};
>> +		unsigned die;
>> +
>> +		flexonenand_get_size(mtd);
>> +
>> +		/* Change the device boundaries if required */
>> +		for (die = 0; die < this->dies; die++)
>> +			if ((!this->boundary_locked[die]) &&
>> +			   (boundary[die] >= 0) &&
>> +			   (boundary[die] != this->boundary[die]))
>> +				flexonenand_set_boundary(mtd, die,
>> +						 boundary[die], lock[die]);
> 
> I am not sure how you intend FLEXONENAND_DIEx_BOUNDARY and FLEXONENAND_DIEx_ISLOCKED
> to be used.  Obviously this code presently does nothing.  If you expect the values
> to be configured for the device, then shouldn't they be config options?

Ok. Added config option for boundary and lock settings.
Configuration of boundary / lock is optional. Default value in config is -1
which will not change existing boundary of Flex-OneNAND.

> 
> Also, ideally there should be a way for the platform driver to override them.
> 

Do you mean runtime configuration of boundary. Then we need to add some ioctl.

>> +	if (FLEXONENAND(this))
>> +		kfree(mtd->eraseregions);
> 
> You can drop the "if (FLEXONENAND(this))", since mtd->eraseregions will
> be NULL if it hasn't been allocated.

ok

>> +		if (FLEXONENAND(this)) {
>> +			onenand_get_block(this, from, &slc);
>> +			from += (1 << bbm->bbt_erase_shift) >> 1;
>> +			if (!slc)
>> +				from += (1 << bbm->bbt_erase_shift) >> 1;
> 
> I think the following syntax is clearer:
> 
> 			if (slc)
> 				from += (1 << bbm->bbt_erase_shift) >> 1;
> 			else
> 				from += (1 << bbm->bbt_erase_shift);

ok. Fixed.

>>   * @chipsize:		[INTERN] the size of one chip for multichip arrays
> 
> 'chipsize' was never properly implemented for multichip devices (it was always
> the same as mtd->size) and it now has another meaning.  For Flex-OneNAND, it is
> the maximum device size.  Please update the comments accordingly.  It is really
> a FIXME.

For now it is FIXME. will fix it

Also, onenand_erase is more readable now.

Thanks,
Rohit

 drivers/mtd/onenand/Kconfig        |   62 +++
 drivers/mtd/onenand/onenand_base.c |  735 +++++++++++++++++++++++++++++++++----
 drivers/mtd/onenand/onenand_bbt.c  |   13 
 drivers/mtd/onenand/onenand_sim.c  |  105 ++++-
 include/linux/mtd/onenand.h        |   34 +
 include/linux/mtd/onenand_regs.h   |   20 -
 6 files changed, 883 insertions(+), 86 deletions(-)

Signed-off-by: Vishak G <vishak.g@samsung.com>
Signed-off-by: Rohit Hagargundgi <h.rohit@samsung.com>
---
---
Adrian Hunter - Nov. 10, 2008, 3:20 p.m.
Rohit wrote:
> Adrian Hunter wrote:
>>> +		this->command(mtd, FLEXONENAND_CMD_PI_ACCESS, die, 0);
>>> +		this->wait(mtd, FL_SYNCING);
>> Why is the error return not checked?
>>
>>> +
>>> +		this->command(mtd, ONENAND_CMD_READ, die, 0);
>>> +		ret = this->wait(mtd, FL_READING);
>> Why is the error return not checked?
>>
>>> +
>>> +		bdry = this->read_word(this->base + ONENAND_DATARAM);
>>> +		locked = bdry >> FLEXONENAND_PI_UNLOCK_SHIFT;
>>> +		locked = (locked == 0x3) ? 0 : 1;
>>> +		this->boundary[die] = bdry & FLEXONENAND_PI_MASK;
>>> +		this->boundary_locked[die] = locked;
>>> +		this->command(mtd, ONENAND_CMD_RESET, 0, 0);
>>> +		ret = this->wait(mtd, FL_RESETING);
>> Why is the error return not checked?
> 
> As per datasheet PI_ACCESS, PI_UPDATE, PI_READ and RESET always succeed.
> PI_ERASE and PI_WRITE can fail. Added error check for PI_ERASE.

So if the device is behaving correctly and the driver has no bugs and there
are no other related hardware errors, then 'ret' will always be zero.  Well,
I would check it anyway, but that's just me.

>>> +	if (FLEXONENAND(this)) {
>>> +		int boundary[] =
>>> +			{FLEXONENAND_DIE0_BOUNDARY, FLEXONENAND_DIE1_BOUNDARY};
>>> +		int lock[] =
>>> +			{FLEXONENAND_DIE0_ISLOCKED, FLEXONENAND_DIE1_ISLOCKED};
>>> +		unsigned die;
>>> +
>>> +		flexonenand_get_size(mtd);
>>> +
>>> +		/* Change the device boundaries if required */
>>> +		for (die = 0; die < this->dies; die++)
>>> +			if ((!this->boundary_locked[die]) &&
>>> +			   (boundary[die] >= 0) &&
>>> +			   (boundary[die] != this->boundary[die]))
>>> +				flexonenand_set_boundary(mtd, die,
>>> +						 boundary[die], lock[die]);
>> I am not sure how you intend FLEXONENAND_DIEx_BOUNDARY and FLEXONENAND_DIEx_ISLOCKED
>> to be used.  Obviously this code presently does nothing.  If you expect the values
>> to be configured for the device, then shouldn't they be config options?
> 
> Ok. Added config option for boundary and lock settings.
> Configuration of boundary / lock is optional. Default value in config is -1
> which will not change existing boundary of Flex-OneNAND.
> 
>> Also, ideally there should be a way for the platform driver to override them.
>>
> 
> Do you mean runtime configuration of boundary. Then we need to add some ioctl.
> 

No I mean a onenand driver (e.g. omap2.c) that reads the values from platform data
and wants to set them.  It is not important.  It can be done later by whomever needs it.

> diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h
> index 9aa2a91..d23eeef 100644
> --- a/include/linux/mtd/onenand.h
> +++ b/include/linux/mtd/onenand.h
> @@ -17,8 +17,23 @@
>  #include <linux/mtd/onenand_regs.h>
>  #include <linux/mtd/bbm.h>
>  
> +#define MAX_DIES		2
>  #define MAX_BUFFERRAM		2
>  
> +#define FLEXONENAND_DIE0_BOUNDARY	CONFIG_MTD_FLEXONENAND_DIE0_BOUNDARY
> +#define FLEXONENAND_DIE1_BOUNDARY	CONFIG_MTD_FLEXONENAND_DIE1_BOUNDARY
> +

CONFIG_MTD_FLEXONENAND_DIEx_BOUNDARY are not necessarily defined i.e. you
need "#if defined ..." there as well.

I briefly tested the driver with an old 'non-Flex' OneNAND and it seemd to work
fine with no apparent effect on performance.  So I have no more issues :-)

Thanks
Adrian
Amit Kumar Sharma - Nov. 11, 2008, 3:31 a.m.
Hi Adrian


> Rohit wrote:
>> Adrian Hunter wrote:
>>>> + this->command(mtd, FLEXONENAND_CMD_PI_ACCESS, die, 
>>>> 0);
>>>> + this->wait(mtd, FL_SYNCING);
>>> Why is the error return not checked?
>>>
>>>> +
>>>> + this->command(mtd, ONENAND_CMD_READ, die, 0);
>>>> + ret = this->wait(mtd, FL_READING);
>>> Why is the error return not checked?
>>>
>>>> +
>>>> + bdry = this->read_word(this->base + ONENAND_DATARAM);
>>>> + locked = bdry >> FLEXONENAND_PI_UNLOCK_SHIFT;
>>>> + locked = (locked == 0x3) ? 0 : 1;
>>>> + this->boundary[die] = bdry & FLEXONENAND_PI_MASK;
>>>> + this->boundary_locked[die] = locked;
>>>> + this->command(mtd, ONENAND_CMD_RESET, 0, 0);
>>>> + ret = this->wait(mtd, FL_RESETING);
>>> Why is the error return not checked?
>>
>> As per datasheet PI_ACCESS, PI_UPDATE, PI_READ and RESET 
>> always succeed.
>> PI_ERASE and PI_WRITE can fail. Added error check for 
>> PI_ERASE.
>
> So if the device is behaving correctly and the driver has 
> no bugs and there
> are no other related hardware errors, then 'ret' will 
> always be zero.  Well,
> I would check it anyway, but that's just me.
>
>>>> + if (FLEXONENAND(this)) {
>>>> + int boundary[] =
>>>> + {FLEXONENAND_DIE0_BOUNDARY, 
>>>> FLEXONENAND_DIE1_BOUNDARY};
>>>> + int lock[] =
>>>> + {FLEXONENAND_DIE0_ISLOCKED, 
>>>> FLEXONENAND_DIE1_ISLOCKED};
>>>> + unsigned die;
>>>> +
>>>> + flexonenand_get_size(mtd);
>>>> +
>>>> + /* Change the device boundaries if required */
>>>> + for (die = 0; die < this->dies; die++)
>>>> + if ((!this->boundary_locked[die]) &&
>>>> +    (boundary[die] >= 0) &&
>>>> +    (boundary[die] != this->boundary[die]))
>>>> + flexonenand_set_boundary(mtd, die,
>>>> + boundary[die], lock[die]);
>>> I am not sure how you intend FLEXONENAND_DIEx_BOUNDARY 
>>> and FLEXONENAND_DIEx_ISLOCKED
>>> to be used.  Obviously this code presently does nothing. 
>>> If you expect the values
>>> to be configured for the device, then shouldn't they be 
>>> config options?
>>
>> Ok. Added config option for boundary and lock settings.
>> Configuration of boundary / lock is optional. Default 
>> value in config is -1
>> which will not change existing boundary of Flex-OneNAND.
>>
>>> Also, ideally there should be a way for the platform 
>>> driver to override them.
>>>
>>
>> Do you mean runtime configuration of boundary. Then we 
>> need to add some ioctl.
>>
>
> No I mean a onenand driver (e.g. omap2.c) that reads the 
> values from platform data
> and wants to set them.  It is not important.  It can be 
> done later by whomever needs it.
>
>> diff --git a/include/linux/mtd/onenand.h 
>> b/include/linux/mtd/onenand.h
>> index 9aa2a91..d23eeef 100644
>> --- a/include/linux/mtd/onenand.h
>> +++ b/include/linux/mtd/onenand.h
>> @@ -17,8 +17,23 @@
>>  #include <linux/mtd/onenand_regs.h>
>>  #include <linux/mtd/bbm.h>
>>  +#define MAX_DIES 2
>>  #define MAX_BUFFERRAM 2
>>  +#define FLEXONENAND_DIE0_BOUNDARY 
>> CONFIG_MTD_FLEXONENAND_DIE0_BOUNDARY
>> +#define FLEXONENAND_DIE1_BOUNDARY 
>> CONFIG_MTD_FLEXONENAND_DIE1_BOUNDARY
>> +
>
> CONFIG_MTD_FLEXONENAND_DIEx_BOUNDARY are not necessarily 
> defined i.e. you
> need "#if defined ..." there as well.
>
> I briefly tested the driver with an old 'non-Flex' OneNAND 
> and it seemd to work
> fine with no apparent effect on performance.  So I have no 
> more issues :-)

we will share iozone result on flexOneNand but during 
testing of  FlexOneNand on kernel 2.6.22 performance results 
are far better then 2.6.27 still we donot know the reasons.
we checked performance for OneNand on same kernel veriosn 
but OneNand also has down performance with 2.6.27 kernel 
version.still a question for us?

>
 Thanks
Amit
Adrian Hunter - Nov. 11, 2008, 7:28 a.m.
Amit Kumar Sharma wrote:
> we will share iozone result on flexOneNand but during 
> testing of  FlexOneNand on kernel 2.6.22 performance results 
> are far better then 2.6.27 still we donot know the reasons.
> we checked performance for OneNand on same kernel veriosn 
> but OneNand also has down performance with 2.6.27 kernel 
> version.still a question for us?

There have been performance regressions in the kernel since
2.6.22 related to the scheduler among other things.  2.6.28
should be better.

Patch

diff --git a/drivers/mtd/onenand/Kconfig b/drivers/mtd/onenand/Kconfig
index 79fa79e..0c8fa54 100644
--- a/drivers/mtd/onenand/Kconfig
+++ b/drivers/mtd/onenand/Kconfig
@@ -71,4 +71,66 @@  config MTD_ONENAND_SIM
 	  The simulator may simulate various OneNAND flash chips for the
 	  OneNAND MTD layer.
 
+config MTD_FLEXONENAND_BOUNDARY
+	bool "Flex-OneNAND Boundary Configuration"
+	depends on MTD_ONENAND
+	default n
+	help
+	  Set SLC and MLC regions of Flex-OneNAND
+
+config MTD_FLEXONENAND_DIE0_BOUNDARY
+	int "Last SLC Block of Flex-OneNAND (min = 0, max = 1023)"
+	depends on MTD_ONENAND && MTD_FLEXONENAND_BOUNDARY
+	default "-1"
+	help
+	  Configure Partition Information (PI) of Flex-OneNAND
+
+	  Entered value indicates index of last SLC block on Flex-OneNAND.
+	  The remaining blocks are configured as MLC blocks.
+
+	  A value of -1 means that PI remains unchanged.
+
+	  This setting applies to :
+		- SDP Flex-OneNAND
+		- Die 1 of DDP Flex-OneNAND.
+
+config MTD_FLEXONENAND_DIE0_ISLOCKED
+	bool "Lock Boundary of Flex-OneNAND"
+	depends on MTD_ONENAND && MTD_FLEXONENAND_BOUNDARY
+	default n
+	help
+	  Configure if Flex-OneNAND boundary should be locked.
+	  Once locked, the boundary cannot be changed.
+
+	  This setting applies to :
+		- SDP Flex-OneNAND
+		- Die 1 of DDP Flex-OneNAND
+
+config MTD_FLEXONENAND_DDP_BOUNDARY
+	bool "Flex-OneNAND DDP Boundary Configuration"
+	depends on MTD_ONENAND && MTD_FLEXONENAND_BOUNDARY
+	default n
+	help
+	  Set SLC and MLC regions of Die 2 of Flex-OneNAND DDP
+
+config MTD_FLEXONENAND_DIE1_BOUNDARY
+	int "Last SLC Block of Flex-OneNAND Die 2 (min = 0, max = 1023)"
+	depends on MTD_ONENAND && MTD_FLEXONENAND_BOUNDARY && MTD_FLEXONENAND_DDP_BOUNDARY
+	default "-1"
+	help
+	  Configure Partition Information (PI) for Die 2 of DDP Flex-OneNAND.
+
+	  Entered value indicates index of last SLC block on Flex-OneNAND.
+	  The remaining blocks are configured as MLC blocks.
+
+	  A value of -1 means that PI remains unchanged.
+
+config MTD_FLEXONENAND_DIE1_ISLOCKED
+	bool "Lock Boundary of Flex-OneNAND Die 2"
+	depends on MTD_ONENAND && MTD_FLEXONENAND_BOUNDARY && MTD_FLEXONENAND_DDP_BOUNDARY
+	default n
+	help
+	  Configure if boundary for Die 2 of DDP Flex-OneNAND should be locked.
+	  Once locked, the boundary cannot be changed.
+
 endif # MTD_ONENAND
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 90ed319..007766d 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -9,6 +9,10 @@ 
  *	auto-placement support, read-while load support, various fixes
  *	Copyright (C) Nokia Corporation, 2007
  *
+ *	Vishak G <vishak.g at samsung.com>, Rohit Hagargundgi <h.rohit at samsung.com>
+ *	Flex-OneNAND support
+ *	Copyright (C) Samsung Electronics, 2008
+ *
  * 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.
@@ -28,6 +32,27 @@ 
 #include <asm/io.h>
 
 /**
+ *  onenand_oob_128 - oob info for Flex-Onenand with 4KB page
+ *  For now, we expose only 64 out of 80 ecc bytes
+ */
+static struct nand_ecclayout onenand_oob_128 = {
+	.eccbytes	= 64,
+	.eccpos		= {
+		6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+		22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+		38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+		54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+		70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
+		86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
+		102, 103, 104, 105
+		},
+	.oobfree	= {
+		{2, 4}, {18, 4}, {34, 4}, {50, 4},
+		{66, 4}, {82, 4}, {98, 4}, {114, 4}
+	}
+};
+
+/**
  * onenand_oob_64 - oob info for large (2KB) page
  */
 static struct nand_ecclayout onenand_oob_64 = {
@@ -65,6 +90,14 @@  static const unsigned char ffchars[] = {
 	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 48 */
 	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
 	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 64 */
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 80 */
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 96 */
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 112 */
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 128 */
 };
 
 /**
@@ -171,6 +204,43 @@  static int onenand_buffer_address(int dataram1, int sectors, int count)
 }
 
 /**
+ * flexonenand_get_block- For given address return block number and if slc
+ * @param this         - OneNAND device structure
+ * @param addr		- Address for which block number is needed
+ * @return isblkslc	- Block is an SLC block or not
+ */
+static unsigned flexonenand_get_block(struct onenand_chip *this, loff_t addr,
+			   unsigned *isblkslc)
+{
+	unsigned boundary, blk, die = 0;
+
+	if (addr >= this->diesize[0]) {
+		die = 1;
+		addr -= this->diesize[0];
+	}
+
+	boundary = this->boundary[die];
+
+	blk = addr >> (this->erase_shift - 1);
+	if (blk > boundary)
+		blk = (blk + boundary + 1) >> 1;
+
+	if (isblkslc)
+		*isblkslc = (blk <= boundary) ? 1 : 0;
+
+	blk += die ? this->density_mask : 0;
+	return blk;
+}
+
+inline unsigned onenand_get_block(struct onenand_chip *this, loff_t addr,
+					unsigned *isblkslc)
+{
+	if (!FLEXONENAND(this))
+		return addr >> this->erase_shift;
+	return flexonenand_get_block(this, addr, isblkslc);
+}
+
+/**
  * onenand_get_density - [DEFAULT] Get OneNAND density
  * @param dev_id	OneNAND device ID
  *
@@ -183,6 +253,22 @@  static inline int onenand_get_density(int dev_id)
 }
 
 /**
+ * eraseregion - [Flex-OneNAND] Return erase region of addr
+ * @param mtd		MTD device structure
+ * @param addr		address whose erase region needs to be identified
+ */
+static inline int eraseregion(struct mtd_info *mtd, loff_t addr)
+{
+	int i;
+
+	for (i = 0; i < mtd->numeraseregions &&
+	     addr >= mtd->eraseregions[i].offset; i++)
+		;
+	i--;
+	return i;
+}
+
+/**
  * onenand_command - [DEFAULT] Send command to OneNAND device
  * @param mtd		MTD device structure
  * @param cmd		the command to be sent
@@ -196,6 +282,7 @@  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 {
 	struct onenand_chip *this = mtd->priv;
 	int value, block, page;
+	unsigned slc = 0;
 
 	/* Address translation */
 	switch (cmd) {
@@ -207,15 +294,27 @@  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 		page = -1;
 		break;
 
+	case FLEXONENAND_CMD_PI_ACCESS:
+		/* addr contains die index */
+		block = addr * this->density_mask;
+		page = -1;
+		break;
+
 	case ONENAND_CMD_ERASE:
 	case ONENAND_CMD_BUFFERRAM:
 	case ONENAND_CMD_OTP_ACCESS:
-		block = (int) (addr >> this->erase_shift);
+		block = onenand_get_block(this, addr, NULL);
 		page = -1;
 		break;
 
+	case FLEXONENAND_CMD_READ_PI:
+		cmd = ONENAND_CMD_READ;
+		block = addr * this->density_mask;
+		page = 0;
+		break;
+
 	default:
-		block = (int) (addr >> this->erase_shift);
+		block = onenand_get_block(this, addr, &slc);
 		page = (int) (addr >> this->page_shift);
 
 		if (ONENAND_IS_2PLANE(this)) {
@@ -227,6 +326,8 @@  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 			page >>= 1;
 		}
 		page &= this->page_mask;
+		if (slc)
+			page &= (this->page_mask >> 1);
 		break;
 	}
 
@@ -236,7 +337,7 @@  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 		value = onenand_bufferram_address(this, block);
 		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
 
-		if (ONENAND_IS_2PLANE(this))
+		if (ONENAND_IS_MLC(this) || ONENAND_IS_2PLANE(this))
 			/* It is always BufferRAM0 */
 			ONENAND_SET_BUFFERRAM0(this);
 		else
@@ -258,13 +359,18 @@  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 
 	if (page != -1) {
 		/* Now we use page size operation */
-		int sectors = 4, count = 4;
+		int sectors = 0, count = 0;
 		int dataram;
 
 		switch (cmd) {
+		case FLEXONENAND_CMD_RECOVER_LSB:
 		case ONENAND_CMD_READ:
 		case ONENAND_CMD_READOOB:
-			dataram = ONENAND_SET_NEXT_BUFFERRAM(this);
+			if (ONENAND_IS_MLC(this))
+				/* It is always BufferRAM0 */
+				dataram = ONENAND_SET_BUFFERRAM0(this);
+			else
+				dataram = ONENAND_SET_NEXT_BUFFERRAM(this);
 			break;
 
 		default:
@@ -293,6 +399,30 @@  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 }
 
 /**
+ * onenand_read_ecc - return ecc status
+ * @param this		onenand chip structure
+ */
+static inline int onenand_read_ecc(struct onenand_chip *this)
+{
+	int ecc, i, result = 0;
+
+	if (!FLEXONENAND(this))
+		return this->read_word(this->base + ONENAND_REG_ECC_STATUS);
+
+	for (i = 0; i < 4; i++) {
+		ecc = this->read_word(this->base + ONENAND_REG_ECC_STATUS + i);
+		if (likely(!ecc))
+			continue;
+		if (ecc & FLEXONENAND_UNCORRECTABLE_ERROR)
+			return ONENAND_ECC_2BIT_ALL;
+		else
+			result = ONENAND_ECC_1BIT_ALL;
+	}
+
+	return result;
+}
+
+/**
  * onenand_wait - [DEFAULT] wait until the command is done
  * @param mtd		MTD device structure
  * @param state		state to select the max. timeout value
@@ -331,14 +461,14 @@  static int onenand_wait(struct mtd_info *mtd, int state)
 	 * power off recovery (POR) test, it should read ECC status first
 	 */
 	if (interrupt & ONENAND_INT_READ) {
-		int ecc = this->read_word(this->base + ONENAND_REG_ECC_STATUS);
+		int ecc = onenand_read_ecc(this);
 		if (ecc) {
 			if (ecc & ONENAND_ECC_2BIT_ALL) {
 				printk(KERN_ERR "onenand_wait: ECC error = 0x%04x\n", ecc);
 				mtd->ecc_stats.failed++;
 				return -EBADMSG;
 			} else if (ecc & ONENAND_ECC_1BIT_ALL) {
-				printk(KERN_INFO "onenand_wait: correctable ECC error = 0x%04x\n", ecc);
+				printk(KERN_DEBUG "onenand_wait: correctable ECC error = 0x%04x\n", ecc);
 				mtd->ecc_stats.corrected++;
 			}
 		}
@@ -656,7 +786,7 @@  static int onenand_check_bufferram(struct mtd_info *mtd, loff_t addr)
 
 	if (found && ONENAND_IS_DDP(this)) {
 		/* Select DataRAM for DDP */
-		int block = (int) (addr >> this->erase_shift);
+		int block = onenand_get_block(this, addr, NULL);
 		int value = onenand_bufferram_address(this, block);
 		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
 	}
@@ -816,6 +946,149 @@  static int onenand_transfer_auto_oob(struct mtd_info *mtd, uint8_t *buf, int col
 }
 
 /**
+ * onenand_recover_lsb - [Flex-OneNAND] Recover LSB page data
+ * @param this		onenand chip device structure
+ * @param addr		address to recover
+ * @param status	return value from onenand_wait / onenand_bbt_wait
+ *
+ * MLC NAND Flash cell has paired pages - LSB page and MSB page. LSB page has
+ * lower page address and MSB page has higher page address in paired pages.
+ * If power off occurs during MSB page program, the paired LSB page data can
+ * become corrupt. LSB page recovery read is a way to read LSB page though page
+ * data are corrupted. When uncorrectable error occurs as a result of LSB page
+ * read after power up, issue LSB page recovery read.
+ */
+static int onenand_recover_lsb(struct mtd_info *mtd, loff_t addr, int status)
+{
+	struct onenand_chip *this = mtd->priv;
+	unsigned slc = 0;
+
+	/* Recovery is only for Flex-OneNAND */
+	if (!FLEXONENAND(this))
+		return status;
+
+	/* check if we failed due to uncorrectable error */
+	if (status != -EBADMSG && status != ONENAND_BBT_READ_ECC_ERROR)
+		return status;
+
+	/* check if address lies in MLC region */
+	onenand_get_block(this, addr, &slc);
+	if (slc)
+		return status;
+
+	/* We are attempting to reread, so decrement stats.failed
+	 * which was incremented by onenand_wait due to read failure
+	 */
+	printk(KERN_INFO "onenand_recover_lsb: Attempting to recover from uncorrectable read\n");
+	mtd->ecc_stats.failed--;
+
+	/* Issue the LSB page recovery command */
+	this->command(mtd, FLEXONENAND_CMD_RECOVER_LSB, addr, this->writesize);
+	return this->wait(mtd, FL_READING);
+}
+
+/**
+ * onenand_mlc_read_ops_nolock - MLC OneNAND read main and/or out-of-band
+ * @param mtd		MTD device structure
+ * @param from		offset to read from
+ * @param ops:		oob operation description structure
+ *
+ * MLC OneNAND / Flex-OneNAND has 4KB page size and 4KB dataram.
+ * So, read-while-load is not present.
+ */
+static int onenand_mlc_read_ops_nolock(struct mtd_info *mtd, loff_t from,
+				struct mtd_oob_ops *ops)
+{
+	struct onenand_chip *this = mtd->priv;
+	struct mtd_ecc_stats stats;
+	size_t len = ops->len;
+	size_t ooblen = ops->ooblen;
+	u_char *buf = ops->datbuf;
+	u_char *oobbuf = ops->oobbuf;
+	int read = 0, column, thislen;
+	int oobread = 0, oobcolumn, thisooblen, oobsize;
+	int ret = 0;
+	int writesize = this->writesize;
+
+	DEBUG(MTD_DEBUG_LEVEL3, "onenand_mlc_read_ops_nolock: from = 0x%08x, len = %i\n", (unsigned int) from, (int) len);
+
+	if (ops->mode == MTD_OOB_AUTO)
+		oobsize = this->ecclayout->oobavail;
+	else
+		oobsize = mtd->oobsize;
+
+	oobcolumn = from & (mtd->oobsize - 1);
+
+	/* Do not allow reads past end of device */
+	if (from + len > mtd->size) {
+		printk(KERN_ERR "onenand_mlc_read_ops_nolock: Attempt read beyond end of device\n");
+		ops->retlen = 0;
+		ops->oobretlen = 0;
+		return -EINVAL;
+	}
+
+	stats = mtd->ecc_stats;
+
+	while (read < len) {
+		cond_resched();
+
+		thislen = min_t(int, writesize, len - read);
+
+		column = from & (writesize - 1);
+		if (column + thislen > writesize)
+			thislen = writesize - column;
+
+		if (!onenand_check_bufferram(mtd, from)) {
+			this->command(mtd, ONENAND_CMD_READ, from, writesize);
+
+			ret = this->wait(mtd, FL_READING);
+			if (unlikely(ret))
+				ret = onenand_recover_lsb(mtd, from, ret);
+			onenand_update_bufferram(mtd, from, !ret);
+			if (ret == -EBADMSG)
+				ret = 0;
+		}
+
+		this->read_bufferram(mtd, ONENAND_DATARAM, buf, column, thislen);
+		if (oobbuf) {
+			thisooblen = oobsize - oobcolumn;
+			thisooblen = min_t(int, thisooblen, ooblen - oobread);
+
+			if (ops->mode == MTD_OOB_AUTO)
+				onenand_transfer_auto_oob(mtd, oobbuf, oobcolumn, thisooblen);
+			else
+				this->read_bufferram(mtd, ONENAND_SPARERAM, oobbuf, oobcolumn, thisooblen);
+			oobread += thisooblen;
+			oobbuf += thisooblen;
+			oobcolumn = 0;
+		}
+
+		read += thislen;
+		if (read == len)
+			break;
+
+		from += thislen;
+		buf += thislen;
+	}
+
+	/*
+	 * Return success, if no ECC failures, else -EBADMSG
+	 * fs driver will take care of that, because
+	 * retlen == desired len and result == -EBADMSG
+	 */
+	ops->retlen = read;
+	ops->oobretlen = oobread;
+
+	if (ret)
+		return ret;
+
+	if (mtd->ecc_stats.failed - stats.failed)
+		return -EBADMSG;
+
+	return mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
+}
+
+/**
  * onenand_read_ops_nolock - [OneNAND Interface] OneNAND read main and/or out-of-band
  * @param mtd		MTD device structure
  * @param from		offset to read from
@@ -962,7 +1235,7 @@  static int onenand_read_oob_nolock(struct mtd_info *mtd, loff_t from,
 	size_t len = ops->ooblen;
 	mtd_oob_mode_t mode = ops->mode;
 	u_char *buf = ops->oobbuf;
-	int ret = 0;
+	int ret = 0, readcmd;
 
 	from += ops->ooboffs;
 
@@ -993,17 +1266,22 @@  static int onenand_read_oob_nolock(struct mtd_info *mtd, loff_t from,
 
 	stats = mtd->ecc_stats;
 
+	readcmd = ONENAND_IS_MLC(this) ? ONENAND_CMD_READ : ONENAND_CMD_READOOB;
+
 	while (read < len) {
 		cond_resched();
 
 		thislen = oobsize - column;
 		thislen = min_t(int, thislen, len);
 
-		this->command(mtd, ONENAND_CMD_READOOB, from, mtd->oobsize);
+		this->command(mtd, readcmd, from, mtd->oobsize);
 
 		onenand_update_bufferram(mtd, from, 0);
 
 		ret = this->wait(mtd, FL_READING);
+		if (unlikely(ret))
+			ret = onenand_recover_lsb(mtd, from, ret);
+
 		if (ret && ret != -EBADMSG) {
 			printk(KERN_ERR "onenand_read_oob_nolock: read failed = 0x%x\n", ret);
 			break;
@@ -1053,6 +1331,7 @@  static int onenand_read_oob_nolock(struct mtd_info *mtd, loff_t from,
 static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
 	size_t *retlen, u_char *buf)
 {
+	struct onenand_chip *this = mtd->priv;
 	struct mtd_oob_ops ops = {
 		.len	= len,
 		.ooblen	= 0,
@@ -1062,7 +1341,9 @@  static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
 	int ret;
 
 	onenand_get_device(mtd, FL_READING);
-	ret = onenand_read_ops_nolock(mtd, from, &ops);
+	ret = ONENAND_IS_MLC(this) ?
+		onenand_mlc_read_ops_nolock(mtd, from, &ops) :
+		onenand_read_ops_nolock(mtd, from, &ops);
 	onenand_release_device(mtd);
 
 	*retlen = ops.retlen;
@@ -1080,6 +1361,7 @@  static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
 static int onenand_read_oob(struct mtd_info *mtd, loff_t from,
 			    struct mtd_oob_ops *ops)
 {
+	struct onenand_chip *this = mtd->priv;
 	int ret;
 
 	switch (ops->mode) {
@@ -1094,7 +1376,9 @@  static int onenand_read_oob(struct mtd_info *mtd, loff_t from,
 
 	onenand_get_device(mtd, FL_READING);
 	if (ops->datbuf)
-		ret = onenand_read_ops_nolock(mtd, from, ops);
+		ret = ONENAND_IS_MLC(this) ?
+			onenand_mlc_read_ops_nolock(mtd, from, ops) :
+			onenand_read_ops_nolock(mtd, from, ops);
 	else
 		ret = onenand_read_oob_nolock(mtd, from, ops);
 	onenand_release_device(mtd);
@@ -1128,11 +1412,11 @@  static int onenand_bbt_wait(struct mtd_info *mtd, int state)
 	ctrl = this->read_word(this->base + ONENAND_REG_CTRL_STATUS);
 
 	if (interrupt & ONENAND_INT_READ) {
-		int ecc = this->read_word(this->base + ONENAND_REG_ECC_STATUS);
+		int ecc = onenand_read_ecc(this);
 		if (ecc & ONENAND_ECC_2BIT_ALL) {
 			printk(KERN_INFO "onenand_bbt_wait: ecc error = 0x%04x"
 				", controller error 0x%04x\n", ecc, ctrl);
-			return ONENAND_BBT_READ_ERROR;
+			return ONENAND_BBT_READ_ECC_ERROR;
 		}
 	} else {
 		printk(KERN_ERR "onenand_bbt_wait: read timeout!"
@@ -1163,7 +1447,7 @@  int onenand_bbt_read_oob(struct mtd_info *mtd, loff_t from,
 {
 	struct onenand_chip *this = mtd->priv;
 	int read = 0, thislen, column;
-	int ret = 0;
+	int ret = 0, readcmd;
 	size_t len = ops->ooblen;
 	u_char *buf = ops->oobbuf;
 
@@ -1183,17 +1467,22 @@  int onenand_bbt_read_oob(struct mtd_info *mtd, loff_t from,
 
 	column = from & (mtd->oobsize - 1);
 
+	readcmd = ONENAND_IS_MLC(this) ? ONENAND_CMD_READ : ONENAND_CMD_READOOB;
+
 	while (read < len) {
 		cond_resched();
 
 		thislen = mtd->oobsize - column;
 		thislen = min_t(int, thislen, len);
 
-		this->command(mtd, ONENAND_CMD_READOOB, from, mtd->oobsize);
+		this->command(mtd, readcmd, from, mtd->oobsize);
 
 		onenand_update_bufferram(mtd, from, 0);
 
 		ret = onenand_bbt_wait(mtd, FL_READING);
+		if (unlikely(ret))
+			ret = onenand_recover_lsb(mtd, from, ret);
+
 		if (ret)
 			break;
 
@@ -1230,9 +1519,11 @@  static int onenand_verify_oob(struct mtd_info *mtd, const u_char *buf, loff_t to
 {
 	struct onenand_chip *this = mtd->priv;
 	u_char *oob_buf = this->oob_buf;
-	int status, i;
+	int status, i, readcmd;
 
-	this->command(mtd, ONENAND_CMD_READOOB, to, mtd->oobsize);
+	readcmd = ONENAND_IS_MLC(this) ? ONENAND_CMD_READ : ONENAND_CMD_READOOB;
+
+	this->command(mtd, readcmd, to, mtd->oobsize);
 	onenand_update_bufferram(mtd, to, 0);
 	status = this->wait(mtd, FL_READING);
 	if (status)
@@ -1586,7 +1877,7 @@  static int onenand_write_oob_nolock(struct mtd_info *mtd, loff_t to,
 {
 	struct onenand_chip *this = mtd->priv;
 	int column, ret = 0, oobsize;
-	int written = 0;
+	int written = 0, oobcmd;
 	u_char *oobbuf;
 	size_t len = ops->ooblen;
 	const u_char *buf = ops->oobbuf;
@@ -1628,6 +1919,8 @@  static int onenand_write_oob_nolock(struct mtd_info *mtd, loff_t to,
 
 	oobbuf = this->oob_buf;
 
+	oobcmd = ONENAND_IS_MLC(this) ? ONENAND_CMD_PROG : ONENAND_CMD_PROGOOB;
+
 	/* Loop until all data write */
 	while (written < len) {
 		int thislen = min_t(int, oobsize, len - written);
@@ -1645,7 +1938,14 @@  static int onenand_write_oob_nolock(struct mtd_info *mtd, loff_t to,
 			memcpy(oobbuf + column, buf, thislen);
 		this->write_bufferram(mtd, ONENAND_SPARERAM, oobbuf, 0, mtd->oobsize);
 
-		this->command(mtd, ONENAND_CMD_PROGOOB, to, mtd->oobsize);
+		if (ONENAND_IS_MLC(this)) {
+			/* Set main area of DataRAM to 0xff*/
+			memset(this->page_buf, 0xff, mtd->writesize);
+			this->write_bufferram(mtd, ONENAND_DATARAM,
+					 this->page_buf, 0, mtd->writesize);
+		}
+
+		this->command(mtd, oobcmd, to, mtd->oobsize);
 
 		onenand_update_bufferram(mtd, to, 0);
 		if (ONENAND_IS_2PLANE(this)) {
@@ -1768,29 +2068,48 @@  static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
 	struct onenand_chip *this = mtd->priv;
 	unsigned int block_size;
-	loff_t addr;
-	int len;
-	int ret = 0;
+	loff_t addr = instr->addr;
+	unsigned int len = instr->len;
+	int ret = 0, i;
+	struct mtd_erase_region_info *region = NULL;
+	unsigned int region_end = 0;
 
-	DEBUG(MTD_DEBUG_LEVEL3, "onenand_erase: start = 0x%08x, len = %i\n", (unsigned int) instr->addr, (unsigned int) instr->len);
+	DEBUG(MTD_DEBUG_LEVEL3, "onenand_erase: start = 0x%08x, len = %i\n", (unsigned int) addr, len);
 
-	block_size = (1 << this->erase_shift);
-
-	/* Start address must align on block boundary */
-	if (unlikely(instr->addr & (block_size - 1))) {
-		printk(KERN_ERR "onenand_erase: Unaligned address\n");
+	/* Do not allow erase past end of device */
+	if (unlikely((len + addr) > mtd->size)) {
+		printk(KERN_ERR "onenand_erase: Erase past end of device\n");
 		return -EINVAL;
 	}
 
-	/* Length must align on block boundary */
-	if (unlikely(instr->len & (block_size - 1))) {
-		printk(KERN_ERR "onenand_erase: Length not block aligned\n");
-		return -EINVAL;
+	if (mtd->numeraseregions > 1) {
+		/* Find the eraseregion of this address */
+		i = eraseregion(mtd, addr);
+		region = &mtd->eraseregions[i];
+
+		block_size = region->erasesize;
+		region_end = region->offset + region->erasesize * region->numblocks;
+
+		/* Start address within region must align on block boundary.
+		 * Erase region's start offset is always block start address.
+		 */
+		if (unlikely((addr - region->offset) & (block_size - 1))) {
+			printk(KERN_ERR "onenand_erase: Unaligned address\n");
+			return -EINVAL;
+		}
+	} else {
+		block_size = mtd->erasesize;
+
+		/* Start address must align on block boundary */
+		if (unlikely(addr & (block_size - 1))) {
+			printk(KERN_ERR "onenand_erase: Unaligned address\n");
+			return -EINVAL;
+		}
 	}
 
-	/* Do not allow erase past end of device */
-	if (unlikely((instr->len + instr->addr) > mtd->size)) {
-		printk(KERN_ERR "onenand_erase: Erase past end of device\n");
+	/* Length must align on block boundary */
+	if (unlikely(len & (block_size - 1))) {
+		printk(KERN_ERR "onenand_erase: Length not block aligned\n");
 		return -EINVAL;
 	}
 
@@ -1800,9 +2119,6 @@  static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
 	onenand_get_device(mtd, FL_ERASING);
 
 	/* Loop throught the pages */
-	len = instr->len;
-	addr = instr->addr;
-
 	instr->state = MTD_ERASING;
 
 	while (len) {
@@ -1822,7 +2138,8 @@  static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
 		ret = this->wait(mtd, FL_ERASING);
 		/* Check, if it is write protected */
 		if (ret) {
-			printk(KERN_ERR "onenand_erase: Failed erase, block %d\n", (unsigned) (addr >> this->erase_shift));
+			printk(KERN_ERR "onenand_erase: Failed erase, block %d\n",
+			 (unsigned)onenand_get_block(this, addr, NULL));
 			instr->state = MTD_ERASE_FAILED;
 			instr->fail_addr = addr;
 			goto erase_exit;
@@ -1830,6 +2147,22 @@  static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
 
 		len -= block_size;
 		addr += block_size;
+
+		if (addr == region_end) {
+			if (!len)
+				break;
+			region++;
+
+			block_size = region->erasesize;
+			region_end = region->offset + region->erasesize * region->numblocks;
+
+			if (len & (block_size - 1)) {
+				/* FIXME: This should be handled at MTD partitioning level. */
+				printk(KERN_ERR "onenand_erase: Unaligned address\n");
+				goto erase_exit;
+			}
+		}
+
 	}
 
 	instr->state = MTD_ERASE_DONE;
@@ -1908,13 +2241,17 @@  static int onenand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 	int block;
 
 	/* Get block number */
-	block = ((int) ofs) >> bbm->bbt_erase_shift;
+	block = onenand_get_block(this, ofs, NULL);
         if (bbm->bbt)
                 bbm->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
 
         /* We write two bytes, so we dont have to mess with 16 bit access */
         ofs += mtd->oobsize + (bbm->badblockpos & ~0x01);
-        return onenand_write_oob_nolock(mtd, ofs, &ops);
+	/* FIXME : What to do when marking SLC block in partition
+	 * 	   with MLC erasesize? For now, it is not advisable to
+	 *	   create partitions containing both SLC and MLC regions.
+	 */
+	return onenand_write_oob_nolock(mtd, ofs, &ops);
 }
 
 /**
@@ -1958,8 +2295,8 @@  static int onenand_do_lock_cmd(struct mtd_info *mtd, loff_t ofs, size_t len, int
 	int start, end, block, value, status;
 	int wp_status_mask;
 
-	start = ofs >> this->erase_shift;
-	end = len >> this->erase_shift;
+	start = onenand_get_block(this, ofs, NULL);
+	end = onenand_get_block(this, ofs + len, NULL) - 1;
 
 	if (cmd == ONENAND_CMD_LOCK)
 		wp_status_mask = ONENAND_WP_LS;
@@ -1971,7 +2308,7 @@  static int onenand_do_lock_cmd(struct mtd_info *mtd, loff_t ofs, size_t len, int
 		/* Set start block address */
 		this->write_word(start, this->base + ONENAND_REG_START_BLOCK_ADDRESS);
 		/* Set end block address */
-		this->write_word(start + end - 1, this->base + ONENAND_REG_END_BLOCK_ADDRESS);
+		this->write_word(end, this->base +  ONENAND_REG_END_BLOCK_ADDRESS);
 		/* Write lock command */
 		this->command(mtd, cmd, 0, 0);
 
@@ -1992,7 +2329,7 @@  static int onenand_do_lock_cmd(struct mtd_info *mtd, loff_t ofs, size_t len, int
 	}
 
 	/* Block lock scheme */
-	for (block = start; block < start + end; block++) {
+	for (block = start; block < end + 1; block++) {
 		/* Set block address */
 		value = onenand_block_address(this, block);
 		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
@@ -2086,7 +2423,6 @@  static int onenand_check_lock_status(struct onenand_chip *this)
 			return 0;
 		}
 	}
-
 	return 1;
 }
 
@@ -2100,7 +2436,7 @@  static void onenand_unlock_all(struct mtd_info *mtd)
 {
 	struct onenand_chip *this = mtd->priv;
 	loff_t ofs = 0;
-	size_t len = this->chipsize;
+	size_t len = mtd->size;
 
 	if (this->options & ONENAND_HAS_UNLOCK_ALL) {
 		/* Set start block address */
@@ -2122,9 +2458,14 @@  static void onenand_unlock_all(struct mtd_info *mtd)
 
 		/* Workaround for all block unlock in DDP */
 		if (ONENAND_IS_DDP(this)) {
-			/* All blocks on another chip */
-			ofs = this->chipsize >> 1;
-			len = this->chipsize >> 1;
+			/* All blocks on another chip
+			 * For Flex-OneNAND with both slc
+			 * mlc regions, we use diesize
+			 */
+			ofs = FLEXONENAND(this) ? this->diesize[0] :
+							this->chipsize >> 1;
+			len = FLEXONENAND(this) ? this->diesize[1] :
+							this->chipsize >> 1;
 		}
 	}
 
@@ -2163,7 +2504,9 @@  static int do_otp_read(struct mtd_info *mtd, loff_t from, size_t len,
 	this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
 	this->wait(mtd, FL_OTPING);
 
-	ret = onenand_read_ops_nolock(mtd, from, &ops);
+	ret = ONENAND_IS_MLC(this) ?
+		onenand_mlc_read_ops_nolock(mtd, from, &ops) :
+		onenand_read_ops_nolock(mtd, from, &ops);
 
 	/* Exit OTP access mode */
 	this->command(mtd, ONENAND_CMD_RESET, 0, 0);
@@ -2230,21 +2573,32 @@  static int do_otp_lock(struct mtd_info *mtd, loff_t from, size_t len,
 		size_t *retlen, u_char *buf)
 {
 	struct onenand_chip *this = mtd->priv;
-	struct mtd_oob_ops ops = {
-		.mode = MTD_OOB_PLACE,
-		.ooblen = len,
-		.oobbuf = buf,
-		.ooboffs = 0,
-	};
+	struct mtd_oob_ops ops;
 	int ret;
 
 	/* Enter OTP access mode */
 	this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
 	this->wait(mtd, FL_OTPING);
 
-	ret = onenand_write_oob_nolock(mtd, from, &ops);
-
-	*retlen = ops.oobretlen;
+	if (FLEXONENAND(this)) {
+		/*
+		 * For Flex-OneNAND, we write lock mark to 1st word of sector 4 of
+		 * main area of page 49.
+		 */
+		ops.len = mtd->writesize;
+		ops.ooblen = 0;
+		ops.datbuf = buf;
+		ops.oobbuf = NULL;
+		ret = onenand_write_ops_nolock(mtd, mtd->writesize * 49, &ops);
+		*retlen = ops.retlen;
+	} else {
+		ops.mode = MTD_OOB_PLACE;
+		ops.ooblen = len;
+		ops.oobbuf = buf;
+		ops.ooboffs = 0;
+		ret = onenand_write_oob_nolock(mtd, from, &ops);
+		*retlen = ops.oobretlen;
+	}
 
 	/* Exit OTP access mode */
 	this->command(mtd, ONENAND_CMD_RESET, 0, 0);
@@ -2428,27 +2782,34 @@  static int onenand_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 			size_t len)
 {
 	struct onenand_chip *this = mtd->priv;
-	u_char *oob_buf = this->oob_buf;
+	u_char *buf = FLEXONENAND(this) ? this->page_buf : this->oob_buf;
 	size_t retlen;
 	int ret;
 
-	memset(oob_buf, 0xff, mtd->oobsize);
+	memset(buf, 0xff, FLEXONENAND(this) ? this->writesize
+						 : mtd->oobsize);
 	/*
 	 * Note: OTP lock operation
 	 *       OTP block : 0xXXFC
 	 *       1st block : 0xXXF3 (If chip support)
 	 *       Both      : 0xXXF0 (If chip support)
 	 */
-	oob_buf[ONENAND_OTP_LOCK_OFFSET] = 0xFC;
+	if (FLEXONENAND(this))
+		buf[FLEXONENAND_OTP_LOCK_OFFSET] = 0xFC;
+	else
+		buf[ONENAND_OTP_LOCK_OFFSET] = 0xFC;
 
 	/*
 	 * Write lock mark to 8th word of sector0 of page0 of the spare0.
 	 * We write 16 bytes spare area instead of 2 bytes.
+	 * For Flex-OneNAND, we write lock mark to 1st word of sector 4 of
+	 * main area of page 49.
 	 */
+
 	from = 0;
-	len = 16;
+	len = FLEXONENAND(this) ? mtd->writesize : 16;
 
-	ret = onenand_otp_walk(mtd, from, len, &retlen, oob_buf, do_otp_lock, MTD_OTP_USER);
+	ret = onenand_otp_walk(mtd, from, len, &retlen, buf, do_otp_lock, MTD_OTP_USER);
 
 	return ret ? : retlen;
 }
@@ -2495,6 +2856,14 @@  static void onenand_check_features(struct mtd_info *mtd)
 		break;
 	}
 
+	if (ONENAND_IS_MLC(this))
+		this->options &= ~ONENAND_HAS_2PLANE;
+
+	if (FLEXONENAND(this)) {
+		this->options &= ~ONENAND_HAS_CONT_LOCK;
+		this->options |= ONENAND_HAS_UNLOCK_ALL;
+	}
+
 	if (this->options & ONENAND_HAS_CONT_LOCK)
 		printk(KERN_DEBUG "Lock scheme is Continuous Lock\n");
 	if (this->options & ONENAND_HAS_UNLOCK_ALL)
@@ -2512,14 +2881,16 @@  static void onenand_check_features(struct mtd_info *mtd)
  */
 static void onenand_print_device_info(int device, int version)
 {
-        int vcc, demuxed, ddp, density;
+	int vcc, demuxed, ddp, density, flexonenand;
 
         vcc = device & ONENAND_DEVICE_VCC_MASK;
         demuxed = device & ONENAND_DEVICE_IS_DEMUX;
         ddp = device & ONENAND_DEVICE_IS_DDP;
         density = onenand_get_density(device);
-        printk(KERN_INFO "%sOneNAND%s %dMB %sV 16-bit (0x%02x)\n",
-                demuxed ? "" : "Muxed ",
+	flexonenand = device & DEVICE_IS_FLEXONENAND;
+	printk(KERN_INFO "%s%sOneNAND%s %dMB %sV 16-bit (0x%02x)\n",
+		demuxed ? "" : "Muxed ",
+		flexonenand ? "Flex-" : "",
                 ddp ? "(DDP)" : "",
                 (16 << density),
                 vcc ? "2.65/3.3" : "1.8",
@@ -2558,6 +2929,182 @@  static int onenand_check_maf(int manuf)
 }
 
 /**
+* flexonenand_get_boundary	- Reads the SLC boundary
+* @param onenand_info		- onenand info structure
+**/
+static int flexonenand_get_boundary(struct mtd_info *mtd)
+{
+	struct onenand_chip *this = mtd->priv;
+	unsigned die, bdry;
+	int ret, syscfg, locked;
+
+	/* Disable ECC */
+	syscfg = this->read_word(this->base + ONENAND_REG_SYS_CFG1);
+	this->write_word((syscfg | 0x0100), this->base + ONENAND_REG_SYS_CFG1);
+
+	for (die = 0; die < this->dies; die++) {
+		this->command(mtd, FLEXONENAND_CMD_PI_ACCESS, die, 0);
+		this->wait(mtd, FL_SYNCING);
+
+		this->command(mtd, FLEXONENAND_CMD_READ_PI, die, 0);
+		ret = this->wait(mtd, FL_READING);
+
+		bdry = this->read_word(this->base + ONENAND_DATARAM);
+		locked = bdry >> FLEXONENAND_PI_UNLOCK_SHIFT;
+		locked = (locked == 0x3) ? 0 : 1;
+		this->boundary[die] = bdry & FLEXONENAND_PI_MASK;
+		this->boundary_locked[die] = locked;
+		this->command(mtd, ONENAND_CMD_RESET, 0, 0);
+		ret = this->wait(mtd, FL_RESETING);
+
+		printk(KERN_INFO "Die %d boundary: %d%s\n", die,
+		       this->boundary[die], locked ? "(Locked)" : "(Unlocked)");
+	}
+
+	/* Enable ECC */
+	this->write_word(syscfg, this->base + ONENAND_REG_SYS_CFG1);
+	return 0;
+}
+
+/**
+ * flexonenand_get_size - Fill up fields in onenand_chip
+ * 			  boundary[], diesize[], chipsize,
+ *			  boundary_locked[]
+ * @param mtd		- MTD device structure
+ */
+static void flexonenand_get_size(struct mtd_info *mtd)
+{
+	struct onenand_chip *this = mtd->priv;
+	int die, ofs, i, eraseshift, density;
+	int blksperdie, maxbdry;
+
+	density = onenand_get_density(this->device_id);
+	blksperdie = ((16 << density) << 20) >> (this->erase_shift);
+	blksperdie >>= ONENAND_IS_DDP(this) ? 1 : 0;
+	maxbdry = blksperdie - 1;
+	eraseshift = this->erase_shift - 1;
+
+	/* this->chipsize = 0; */
+	mtd->numeraseregions = this->dies << 1;
+
+	/* This fills up the device boundary */
+	flexonenand_get_boundary(mtd);
+	die = ofs = 0;
+	i = -1;
+	for (; die < this->dies; die++) {
+		if (!die || this->boundary[die-1] != maxbdry) {
+			i++;
+			mtd->eraseregions[i].offset = ofs;
+			mtd->eraseregions[i].erasesize = 1 << eraseshift;
+			mtd->eraseregions[i].numblocks =
+							this->boundary[die] + 1;
+			ofs += mtd->eraseregions[i].numblocks << eraseshift;
+			eraseshift++;
+		} else {
+			mtd->numeraseregions -= 1;
+			mtd->eraseregions[i].numblocks +=
+							this->boundary[die] + 1;
+			ofs += (this->boundary[die] + 1) << (eraseshift - 1);
+		}
+		if (this->boundary[die] != maxbdry) {
+			i++;
+			mtd->eraseregions[i].offset = ofs;
+			mtd->eraseregions[i].erasesize = 1 << eraseshift;
+			mtd->eraseregions[i].numblocks = maxbdry ^
+							 this->boundary[die];
+			ofs += mtd->eraseregions[i].numblocks << eraseshift;
+			eraseshift--;
+		} else
+			mtd->numeraseregions -= 1;
+	}
+
+	mtd->erasesize = 1 << (this->erase_shift);
+	if (mtd->numeraseregions == 1)
+		mtd->erasesize >>= 1;
+
+	printk(KERN_INFO "Device has %d eraseregions\n", mtd->numeraseregions);
+	for (i = 0; i < mtd->numeraseregions; i++)
+		printk(KERN_INFO "[offset: 0x%08x, erasesize: 0x%05x,"
+			 " numblocks: %04u]\n", mtd->eraseregions[i].offset,
+			mtd->eraseregions[i].erasesize,
+			mtd->eraseregions[i].numblocks);
+
+	for (die = 0, mtd->size = 0; die < this->dies; die++) {
+		this->diesize[die] = (blksperdie << this->erase_shift);
+		this->diesize[die] -= (this->boundary[die] + 1)
+						 << (this->erase_shift - 1);
+		mtd->size += this->diesize[die];
+	}
+
+	/* this->chipsize represents maximum possible chip size */
+	this->chipsize = (16 << density) << 20;
+}
+
+/**
+ * flexonenand_set_boundary	- Writes the SLC boundary
+ * @param onenand_info		- onenand info structure
+ */
+static int flexonenand_set_boundary(struct mtd_info *mtd, unsigned die,
+						int boundary, int lock)
+{
+	struct onenand_chip *this = mtd->priv;
+	int ret, density, blksperdie;
+	loff_t addr;
+
+	density = onenand_get_density(this->device_id);
+	blksperdie = ((16 << density) << 20) >> this->erase_shift;
+	blksperdie >>= ONENAND_IS_DDP(this) ? 1 : 0;
+
+	printk(KERN_INFO "flexonenand_set_boundary: Changing die %d boundary: %d%s\n",
+			die, boundary, lock ? "(Locked)" : "(Unlocked)");
+	if (boundary >= blksperdie) {
+		printk(KERN_ERR "flexonenand_set_boundary: Invalid boundary value. "
+				"Boundary not changed.\n");
+		return -1;
+	}
+
+	if (this->boundary_locked[die]) {
+		printk(KERN_ERR "flexonenand_set_boundary: Die boundary is locked. "
+				"Boundary not changed.\n");
+		return -1;
+	}
+
+	addr = die ? this->diesize[0] : 0;
+
+	boundary &= FLEXONENAND_PI_MASK;
+	boundary |= lock ? 0 : (3 << FLEXONENAND_PI_UNLOCK_SHIFT);
+
+	this->command(mtd, FLEXONENAND_CMD_PI_ACCESS, die, 0);
+	this->wait(mtd, FL_SYNCING);
+
+	this->command(mtd, ONENAND_CMD_ERASE, addr, 0);
+	ret = this->wait(mtd, FL_ERASING);
+	if (ret) {
+		printk(KERN_ERR "flexonenand_set_boundary: Failed PI erase for Die %d\n", die);
+		goto out;
+	}
+
+
+	this->write_word(boundary, this->base + ONENAND_DATARAM);
+	this->command(mtd, ONENAND_CMD_PROG, addr, 0);
+	ret = this->wait(mtd, FL_WRITING);
+	if (ret) {
+		printk(KERN_ERR "flexonenand_set_boundary: Failed PI write for Die %d\n", die);
+		goto out;
+	}
+
+	this->command(mtd, FLEXONENAND_CMD_PI_UPDATE, die, 0);
+	ret = this->wait(mtd, FL_WRITING);
+out:
+	this->write_word(ONENAND_CMD_RESET, this->base + ONENAND_REG_COMMAND);
+	this->wait(mtd, FL_RESETING);
+	if (!ret)
+		/* Recalculate device size on boundary change*/
+		flexonenand_get_size(mtd);
+	return ret;
+}
+
+/**
  * onenand_probe - [OneNAND Interface] Probe the OneNAND device
  * @param mtd		MTD device structure
  *
@@ -2599,6 +3146,7 @@  static int onenand_probe(struct mtd_info *mtd)
 	maf_id = this->read_word(this->base + ONENAND_REG_MANUFACTURER_ID);
 	dev_id = this->read_word(this->base + ONENAND_REG_DEVICE_ID);
 	ver_id = this->read_word(this->base + ONENAND_REG_VERSION_ID);
+	this->technology = this->read_word(this->base + ONENAND_REG_TECHNOLOGY);
 
 	/* Check OneNAND device */
 	if (maf_id != bram_maf_id || dev_id != bram_dev_id)
@@ -2610,20 +3158,35 @@  static int onenand_probe(struct mtd_info *mtd)
 	this->version_id = ver_id;
 
 	density = onenand_get_density(dev_id);
-	this->chipsize = (16 << density) << 20;
+	if (FLEXONENAND(this)) {
+		this->dies = ONENAND_IS_DDP(this) ? 2 : 1;
+		/* Maximum possible erase regions */
+		mtd->numeraseregions = this->dies << 1;
+		mtd->eraseregions = kzalloc(sizeof(struct mtd_erase_region_info)
+					* (this->dies << 1), GFP_KERNEL);
+		if (!mtd->eraseregions)
+			return -ENOMEM;
+	}
+	this->chipsize = FLEXONENAND(this) ? 0 : (16 << density) << 20;
 	/* Set density mask. it is used for DDP */
 	if (ONENAND_IS_DDP(this))
-		this->density_mask = (1 << (density + 6));
+		this->density_mask = (1 << (density +
+						 (FLEXONENAND(this) ? 4 : 6)));
 	else
 		this->density_mask = 0;
 
 	/* OneNAND page size & block size */
 	/* The data buffer size is equal to page size */
 	mtd->writesize = this->read_word(this->base + ONENAND_REG_DATA_BUFFER_SIZE);
+	/* We use the full BufferRAM */
+	if (ONENAND_IS_MLC(this))
+		mtd->writesize <<= 1;
+
 	mtd->oobsize = mtd->writesize >> 5;
 	/* Pages per a block are always 64 in OneNAND */
 	mtd->erasesize = mtd->writesize << 6;
-
+	/* Flex-OneNAND always has 128 pages per block */
+	mtd->erasesize <<= FLEXONENAND(this) ? 1 : 0;
 	this->erase_shift = ffs(mtd->erasesize) - 1;
 	this->page_shift = ffs(mtd->writesize) - 1;
 	this->page_mask = (1 << (this->erase_shift - this->page_shift)) - 1;
@@ -2632,7 +3195,24 @@  static int onenand_probe(struct mtd_info *mtd)
 
 	/* REVIST: Multichip handling */
 
-	mtd->size = this->chipsize;
+	if (FLEXONENAND(this)) {
+		int boundary[] =
+			{FLEXONENAND_DIE0_BOUNDARY, FLEXONENAND_DIE1_BOUNDARY};
+		int lock[] =
+			{FLEXONENAND_DIE0_ISLOCKED, FLEXONENAND_DIE1_ISLOCKED};
+		unsigned die;
+
+		flexonenand_get_size(mtd);
+
+		/* Change the device boundaries if required */
+		for (die = 0; die < this->dies; die++)
+			if ((!this->boundary_locked[die]) &&
+			   (boundary[die] >= 0) &&
+			   (boundary[die] != this->boundary[die]))
+				flexonenand_set_boundary(mtd, die,
+						 boundary[die], lock[die]);
+	} else
+		mtd->size = this->chipsize;
 
 	/* Check OneNAND features */
 	onenand_check_features(mtd);
@@ -2749,6 +3329,10 @@  int onenand_scan(struct mtd_info *mtd, int maxchips)
 	 * Allow subpage writes up to oobsize.
 	 */
 	switch (mtd->oobsize) {
+	case 128:
+		this->ecclayout = &onenand_oob_128;
+		mtd->subpage_sft = 0;
+		break;
 	case 64:
 		this->ecclayout = &onenand_oob_64;
 		mtd->subpage_sft = 2;
@@ -2768,6 +3352,10 @@  int onenand_scan(struct mtd_info *mtd, int maxchips)
 		break;
 	}
 
+	/* Don't allow the sub-page write in MLC */
+	if (ONENAND_IS_MLC(this))
+		mtd->subpage_sft = 0;
+
 	this->subpagesize = mtd->writesize >> mtd->subpage_sft;
 
 	/*
@@ -2843,6 +3431,7 @@  void onenand_release(struct mtd_info *mtd)
 		kfree(this->page_buf);
 	if (this->options & ONENAND_OOBBUF_ALLOC)
 		kfree(this->oob_buf);
+	kfree(mtd->eraseregions);
 }
 
 EXPORT_SYMBOL_GPL(onenand_scan);
diff --git a/drivers/mtd/onenand/onenand_bbt.c b/drivers/mtd/onenand/onenand_bbt.c
index 2f53b51..20fc070 100644
--- a/drivers/mtd/onenand/onenand_bbt.c
+++ b/drivers/mtd/onenand/onenand_bbt.c
@@ -60,6 +60,7 @@  static int create_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
 	struct bbm_info *bbm = this->bbm;
 	int i, j, numblocks, len, scanlen;
 	int startblock;
+	unsigned slc = 0;
 	loff_t from;
 	size_t readlen, ooblen;
 	struct mtd_oob_ops ops;
@@ -76,7 +77,7 @@  static int create_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
 	/* Note that numblocks is 2 * (real numblocks) here;
 	 * see i += 2 below as it makses shifting and masking less painful
 	 */
-	numblocks = mtd->size >> (bbm->bbt_erase_shift - 1);
+	numblocks = this->chipsize >> (bbm->bbt_erase_shift - 1);
 	startblock = 0;
 	from = 0;
 
@@ -106,7 +107,11 @@  static int create_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
 			}
 		}
 		i += 2;
-		from += (1 << bbm->bbt_erase_shift);
+		onenand_get_block(this, from, &slc);
+		if (slc)
+			from += (1 << bbm->bbt_erase_shift) >> 1;
+		else
+			from += (1 << bbm->bbt_erase_shift);
 	}
 
 	return 0;
@@ -143,7 +148,7 @@  static int onenand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt)
 	uint8_t res;
 
 	/* Get block number * 2 */
-	block = (int) (offs >> (bbm->bbt_erase_shift - 1));
+	block = (int) (onenand_get_block(this, offs, NULL) << 1);
 	res = (bbm->bbt[block >> 3] >> (block & 0x06)) & 0x03;
 
 	DEBUG(MTD_DEBUG_LEVEL2, "onenand_isbad_bbt: bbt info for offs 0x%08x: (block %d) 0x%02x\n",
@@ -178,7 +183,7 @@  int onenand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd)
 	struct bbm_info *bbm = this->bbm;
 	int len, ret = 0;
 
-	len = mtd->size >> (this->erase_shift + 2);
+	len = this->chipsize >> (this->erase_shift + 2);
 	/* Allocate memory (2bit per block) and clear the memory bad block table */
 	bbm->bbt = kzalloc(len, GFP_KERNEL);
 	if (!bbm->bbt) {
diff --git a/drivers/mtd/onenand/onenand_sim.c b/drivers/mtd/onenand/onenand_sim.c
index d64200b..c66946e 100644
--- a/drivers/mtd/onenand/onenand_sim.c
+++ b/drivers/mtd/onenand/onenand_sim.c
@@ -6,6 +6,10 @@ 
  *  Copyright © 2005-2007 Samsung Electronics
  *  Kyungmin Park <kyungmin.park@samsung.com>
  *
+ *  Vishak G <vishak.g at samsung.com>, Rohit Hagargundgi <h.rohit at samsung.com>
+ *  Flex-OneNAND simulator support
+ *  Copyright (C) Samsung Electronics, 2008
+ *
  * 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.
@@ -24,16 +28,38 @@ 
 #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
+
+#define CONFIG_FLEXONENAND ((CONFIG_ONENAND_SIM_DEVICE_ID >> 9) & 1)
+
 #ifndef CONFIG_ONENAND_SIM_VERSION_ID
 #define CONFIG_ONENAND_SIM_VERSION_ID           0x1e
 #endif
 
+#ifndef CONFIG_ONENAND_SIM_TECHNOLOGY_ID
+#define CONFIG_ONENAND_SIM_TECHNOLOGY_ID CONFIG_FLEXONENAND
+#endif
+
+/* Initial boundary values for Flex-OneNAND Simulator */
+#ifndef CONFIG_FLEXONENAND_SIM_DIE0_BOUNDARY
+#define CONFIG_FLEXONENAND_SIM_DIE0_BOUNDARY	0x01
+#endif
+
+#ifndef CONFIG_FLEXONENAND_SIM_DIE1_BOUNDARY
+#define CONFIG_FLEXONENAND_SIM_DIE1_BOUNDARY	0x01
+#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;
+static int technology_id = CONFIG_ONENAND_SIM_TECHNOLOGY_ID;
+static int boundary[] = {
+	CONFIG_FLEXONENAND_SIM_DIE0_BOUNDARY,
+	CONFIG_FLEXONENAND_SIM_DIE1_BOUNDARY,
+};
 
 struct onenand_flash {
 	void __iomem *base;
@@ -57,12 +83,18 @@  struct onenand_flash {
 	(writew(v, this->base + ONENAND_REG_WP_STATUS))
 
 /* It has all 0xff chars */
-#define MAX_ONENAND_PAGESIZE		(2048 + 64)
+#define MAX_ONENAND_PAGESIZE		(4096 + 128)
 static unsigned char *ffchars;
 
+#if CONFIG_FLEXONENAND
+#define PARTITION_NAME "Flex-OneNAND simulator partition"
+#else
+#define PARTITION_NAME "OneNAND simulator partition"
+#endif
+
 static struct mtd_partition os_partitions[] = {
 	{
-		.name		= "OneNAND simulator partition",
+		.name		= PARTITION_NAME,
 		.offset		= 0,
 		.size		= MTDPART_SIZ_FULL,
 	},
@@ -104,6 +136,7 @@  static void onenand_lock_handle(struct onenand_chip *this, int cmd)
 
 	switch (cmd) {
 	case ONENAND_CMD_UNLOCK:
+	case ONENAND_CMD_UNLOCK_ALL:
 		if (block_lock_scheme)
 			ONENAND_SET_WP_STATUS(ONENAND_WP_US, this);
 		else
@@ -228,10 +261,11 @@  static void onenand_data_handle(struct onenand_chip *this, int cmd,
 {
 	struct mtd_info *mtd = &info->mtd;
 	struct onenand_flash *flash = this->priv;
-	int main_offset, spare_offset;
+	int main_offset, spare_offset, die = 0;
 	void __iomem *src;
 	void __iomem *dest;
-	unsigned int i;
+	unsigned int i, slc = 0;
+	static int pi_operation;
 
 	if (dataram) {
 		main_offset = mtd->writesize;
@@ -241,10 +275,27 @@  static void onenand_data_handle(struct onenand_chip *this, int cmd,
 		spare_offset = 0;
 	}
 
+	if (pi_operation) {
+		die = readw(this->base + ONENAND_REG_START_ADDRESS2);
+		die >>= ONENAND_DDP_SHIFT;
+	}
+
 	switch (cmd) {
+	case FLEXONENAND_CMD_PI_ACCESS:
+		pi_operation = 1;
+		break;
+
+	case ONENAND_CMD_RESET:
+		pi_operation = 0;
+		break;
+
 	case ONENAND_CMD_READ:
 		src = ONENAND_CORE(flash) + offset;
 		dest = ONENAND_MAIN_AREA(this, main_offset);
+		if (pi_operation) {
+			writew(boundary[die], this->base + ONENAND_DATARAM);
+			break;
+		}
 		memcpy(dest, src, mtd->writesize);
 		/* Fall through */
 
@@ -257,6 +308,10 @@  static void onenand_data_handle(struct onenand_chip *this, int cmd,
 	case ONENAND_CMD_PROG:
 		src = ONENAND_MAIN_AREA(this, main_offset);
 		dest = ONENAND_CORE(flash) + offset;
+		if (pi_operation) {
+			boundary[die] = readw(this->base + ONENAND_DATARAM);
+			break;
+		}
 		/* To handle partial write */
 		for (i = 0; i < (1 << mtd->subpage_sft); i++) {
 			int off = i * this->subpagesize;
@@ -284,9 +339,16 @@  static void onenand_data_handle(struct onenand_chip *this, int cmd,
 		break;
 
 	case ONENAND_CMD_ERASE:
+		if (pi_operation)
+			break;
+		onenand_get_block(this, offset, &slc);
+		if (slc && (mtd->numeraseregions > 1))
+			mtd->erasesize >>= 1;
 		memset(ONENAND_CORE(flash) + offset, 0xff, mtd->erasesize);
 		memset(ONENAND_CORE_SPARE(flash, this, offset), 0xff,
 		       (mtd->erasesize >> 5));
+		if (slc && (mtd->numeraseregions > 1))
+			mtd->erasesize <<= 1;
 		break;
 
 	default:
@@ -295,6 +357,29 @@  static void onenand_data_handle(struct onenand_chip *this, int cmd,
 }
 
 /**
+ * flexonenand_get_addr - Return address of the block
+ * @block:		Block number on Flex-OneNAND
+ *
+ */
+loff_t flexonenand_get_addr(struct onenand_chip *this, int block)
+{
+	loff_t ofs;
+	int die = 0, boundary;
+
+	ofs = 0;
+	if (ONENAND_IS_DDP(this) && block >= this->density_mask) {
+		block -= this->density_mask;
+		die = 1;
+		ofs = this->diesize[0];
+	}
+	boundary = this->boundary[die];
+	ofs += block << (this->erase_shift - 1);
+	if (block > (boundary + 1))
+		ofs += (block - boundary - 1) << (this->erase_shift - 1);
+	return ofs;
+}
+
+/**
  * onenand_command_handle - Handle command
  * @this:		OneNAND device structure
  * @cmd:		The command to be sent
@@ -338,8 +423,12 @@  static void onenand_command_handle(struct onenand_chip *this, int cmd)
 		break;
 	}
 
-	if (block != -1)
-		offset += block << this->erase_shift;
+	if (block != -1) {
+		if (FLEXONENAND(this))
+			offset = flexonenand_get_addr(this, block);
+		else
+			offset += block << this->erase_shift;
+	}
 
 	if (page != -1)
 		offset += page << this->page_shift;
@@ -390,6 +479,7 @@  static int __init flash_init(struct onenand_flash *flash)
 	}
 
 	density = device_id >> ONENAND_DEVICE_DENSITY_SHIFT;
+	density &= ONENAND_DEVICE_DENSITY_MASK;
 	size = ((16 << 20) << density);
 
 	ONENAND_CORE(flash) = vmalloc(size + (size >> 5));
@@ -405,8 +495,9 @@  static int __init flash_init(struct onenand_flash *flash)
 	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);
+	writew(technology_id, flash->base + ONENAND_REG_TECHNOLOGY);
 
-	if (density < 2)
+	if (density < 2 && (!CONFIG_FLEXONENAND))
 		buffer_size = 0x0400;	/* 1KiB page */
 	else
 		buffer_size = 0x0800;	/* 2KiB page */
diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h
index 9aa2a91..d23eeef 100644
--- a/include/linux/mtd/onenand.h
+++ b/include/linux/mtd/onenand.h
@@ -17,8 +17,23 @@ 
 #include <linux/mtd/onenand_regs.h>
 #include <linux/mtd/bbm.h>
 
+#define MAX_DIES		2
 #define MAX_BUFFERRAM		2
 
+#define FLEXONENAND_DIE0_BOUNDARY	CONFIG_MTD_FLEXONENAND_DIE0_BOUNDARY
+#define FLEXONENAND_DIE1_BOUNDARY	CONFIG_MTD_FLEXONENAND_DIE1_BOUNDARY
+
+#if defined CONFIG_MTD_FLEXONENAND_DIE0_ISLOCKED
+#define FLEXONENAND_DIE0_ISLOCKED	1
+#else
+#define FLEXONENAND_DIE0_ISLOCKED	0
+#endif
+#if defined CONFIG_MTD_FLEXONENAND_DIE1_ISLOCKED
+#define FLEXONENAND_DIE1_ISLOCKED	1
+#else
+#define FLEXONENAND_DIE1_ISLOCKED	0
+#endif
+
 /* Scan and identify a OneNAND device */
 extern int onenand_scan(struct mtd_info *mtd, int max_chips);
 /* Free resources held by the OneNAND device */
@@ -51,7 +66,14 @@  struct onenand_bufferram {
 /**
  * struct onenand_chip - OneNAND Private Flash Chip Data
  * @base:		[BOARDSPECIFIC] address to access OneNAND
+ * @dies:		[INTERN][FLEX-ONENAND] number of dies on chip
+ * @boundary:		[INTERN][FLEX-ONENAND] Boundary of the dies
+ * @boundary_locked:	[INTERN][FLEX-ONENAND] TRUE indicates die boundary
+ * 			is locked and cannot be changed
+ * @diesize:		[INTERN][FLEX-ONENAND] Size of the dies
  * @chipsize:		[INTERN] the size of one chip for multichip arrays
+ *			FIXME For Flex-OneNAND, chipsize holds maximum possible
+ *			device size ie when all blocks are considered MLC
  * @device_id:		[INTERN] device ID
  * @density_mask:	chip density, used for DDP devices
  * @verstion_id:	[INTERN] version ID
@@ -92,9 +114,14 @@  struct onenand_bufferram {
  */
 struct onenand_chip {
 	void __iomem		*base;
+	unsigned		dies;
+	unsigned		boundary[MAX_DIES];
+	unsigned int 		boundary_locked[MAX_DIES];
+	unsigned int		diesize[MAX_DIES];
 	unsigned int		chipsize;
 	unsigned int		device_id;
 	unsigned int		version_id;
+	unsigned int		technology;
 	unsigned int		density_mask;
 	unsigned int		options;
 
@@ -145,6 +172,8 @@  struct onenand_chip {
 #define ONENAND_SET_BUFFERRAM0(this)		(this->bufferram_index = 0)
 #define ONENAND_SET_BUFFERRAM1(this)		(this->bufferram_index = 1)
 
+#define FLEXONENAND(this)						\
+	(this->device_id & DEVICE_IS_FLEXONENAND)
 #define ONENAND_GET_SYS_CFG1(this)					\
 	(this->read_word(this->base + ONENAND_REG_SYS_CFG1))
 #define ONENAND_SET_SYS_CFG1(v, this)					\
@@ -153,6 +182,9 @@  struct onenand_chip {
 #define ONENAND_IS_DDP(this)						\
 	(this->device_id & ONENAND_DEVICE_IS_DDP)
 
+#define ONENAND_IS_MLC(this)						\
+	(this->technology & ONENAND_TECHNOLOGY_IS_MLC)
+
 #ifdef CONFIG_MTD_ONENAND_2X_PROGRAM
 #define ONENAND_IS_2PLANE(this)						\
 	(this->options & ONENAND_HAS_2PLANE)
@@ -189,5 +221,7 @@  struct onenand_manufacturers {
 
 int onenand_bbt_read_oob(struct mtd_info *mtd, loff_t from,
 			 struct mtd_oob_ops *ops);
+unsigned onenand_get_block(struct onenand_chip *this, loff_t addr,
+			 unsigned *isblkslc);
 
 #endif	/* __LINUX_MTD_ONENAND_H */
diff --git a/include/linux/mtd/onenand_regs.h b/include/linux/mtd/onenand_regs.h
index 0c6bbe2..86a6bbe 100644
--- a/include/linux/mtd/onenand_regs.h
+++ b/include/linux/mtd/onenand_regs.h
@@ -67,6 +67,9 @@ 
 /*
  * Device ID Register F001h (R)
  */
+#define DEVICE_IS_FLEXONENAND		(1 << 9)
+#define FLEXONENAND_PI_MASK		(0x3ff)
+#define FLEXONENAND_PI_UNLOCK_SHIFT	(14)
 #define ONENAND_DEVICE_DENSITY_MASK	(0xf)
 #define ONENAND_DEVICE_DENSITY_SHIFT	(4)
 #define ONENAND_DEVICE_IS_DDP		(1 << 3)
@@ -84,6 +87,11 @@ 
 #define ONENAND_VERSION_PROCESS_SHIFT	(8)
 
 /*
+ * Technology Register F006h (R)
+ */
+#define ONENAND_TECHNOLOGY_IS_MLC	(1 << 0)
+
+/*
  * Start Address 1 F100h (R/W) & Start Address 2 F101h (R/W)
  */
 #define ONENAND_DDP_SHIFT		(15)
@@ -93,7 +101,8 @@ 
 /*
  * Start Address 8 F107h (R/W)
  */
-#define ONENAND_FPA_MASK		(0x3f)
+/* Note: It's actually 0x3f in case of SLC */
+#define ONENAND_FPA_MASK		(0x7f)
 #define ONENAND_FPA_SHIFT		(2)
 #define ONENAND_FSA_MASK		(0x03)
 
@@ -105,7 +114,8 @@ 
 #define ONENAND_BSA_BOOTRAM		(0 << 2)
 #define ONENAND_BSA_DATARAM0		(2 << 2)
 #define ONENAND_BSA_DATARAM1		(3 << 2)
-#define ONENAND_BSC_MASK		(0x03)
+/* Note: It's actually 0x03 in case of SLC */
+#define ONENAND_BSC_MASK		(0x07)
 
 /*
  * Command Register F220h (R/W)
@@ -124,9 +134,13 @@ 
 #define ONENAND_CMD_RESET		(0xF0)
 #define ONENAND_CMD_OTP_ACCESS		(0x65)
 #define ONENAND_CMD_READID		(0x90)
+#define FLEXONENAND_CMD_PI_UPDATE	(0x05)
+#define FLEXONENAND_CMD_PI_ACCESS	(0x66)
+#define FLEXONENAND_CMD_RECOVER_LSB	(0x05)
 
 /* NOTE: Those are not *REAL* commands */
 #define ONENAND_CMD_BUFFERRAM		(0x1978)
+#define FLEXONENAND_CMD_READ_PI		(0x1985)
 
 /*
  * System Configuration 1 Register F221h (R, R/W)
@@ -192,10 +206,12 @@ 
 #define ONENAND_ECC_1BIT_ALL		(0x5555)
 #define ONENAND_ECC_2BIT		(1 << 1)
 #define ONENAND_ECC_2BIT_ALL		(0xAAAA)
+#define FLEXONENAND_UNCORRECTABLE_ERROR	(0x1010)
 
 /*
  * One-Time Programmable (OTP)
  */
+#define FLEXONENAND_OTP_LOCK_OFFSET		(2048)
 #define ONENAND_OTP_LOCK_OFFSET		(14)
 
 #endif	/* __ONENAND_REG_H */