Patchwork [2/2] MTD: OneNAND: multiblock erase support

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Submitter Mika Korhonen
Date Sept. 3, 2009, 10:54 a.m.
Message ID <1251975273-12432-3-git-send-email-ext-mika.2.korhonen@nokia.com>
Download mbox | patch
Permalink /patch/32877/
State New
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Comments

Mika Korhonen - Sept. 3, 2009, 10:54 a.m.
Add support for multiblock erase command. OneNANDs (excluding Flex-OneNAND)
are capable of simultaneous erase of up to 64 eraseblocks which is much
faster.
This changes the erase requests for regions covering multiple eraseblocks
to be performed using multiblock erase.

Signed-off-by: Mika Korhonen <ext-mika.2.korhonen@nokia.com>
---
 drivers/mtd/onenand/omap2.c        |   22 ++++-
 drivers/mtd/onenand/onenand_base.c |  151 +++++++++++++++++++++++++++++++++++-
 include/linux/mtd/onenand.h        |    2 +
 include/linux/mtd/onenand_regs.h   |    2 +
 4 files changed, 171 insertions(+), 6 deletions(-)
Adrian Hunter - Sept. 16, 2009, 4:32 p.m.
Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
> Add support for multiblock erase command. OneNANDs (excluding Flex-OneNAND)
> are capable of simultaneous erase of up to 64 eraseblocks which is much
> faster.
> This changes the erase requests for regions covering multiple eraseblocks
> to be performed using multiblock erase.
> 
> Signed-off-by: Mika Korhonen <ext-mika.2.korhonen@nokia.com>
> ---

A few comments below.

>  drivers/mtd/onenand/omap2.c        |   22 ++++-
>  drivers/mtd/onenand/onenand_base.c |  151 +++++++++++++++++++++++++++++++++++-
>  include/linux/mtd/onenand.h        |    2 +
>  include/linux/mtd/onenand_regs.h   |    2 +
>  4 files changed, 171 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/mtd/onenand/omap2.c b/drivers/mtd/onenand/omap2.c
> index 0108ed4..47ae815 100644
> --- a/drivers/mtd/onenand/omap2.c
> +++ b/drivers/mtd/onenand/omap2.c
> @@ -112,10 +112,24 @@ static int omap2_onenand_wait(struct mtd_info *mtd, int state)
>  	unsigned long timeout;
>  	u32 syscfg;
>  
> -	if (state == FL_RESETING) {
> -		int i;
> +	if (state == FL_RESETING || state == FL_PREPARING_ERASE ||
> +		state == FL_VERIFYING_ERASE) {

Better to align like this

+	    state == FL_VERIFYING_ERASE) {


> +

Drop this blank line

> +		int i = 21;
> +		unsigned int intr_flags = ONENAND_INT_MASTER;

And add a blank line here

> +		switch (state) {
> +		case FL_RESETING:
> +			intr_flags |= ONENAND_INT_RESET;
> +			break;
> +		case FL_PREPARING_ERASE:
> +			intr_flags |= ONENAND_INT_ERASE;
> +			break;
> +		case FL_VERIFYING_ERASE:
> +			i = 51;

I see 100us for this in some versions.  Perhaps Kyungmin can suggest
a value.

> +			break;
> +		}
>  
> -		for (i = 0; i < 20; i++) {
> +		while (--i) {
>  			udelay(1);
>  			intr = read_reg(c, ONENAND_REG_INTERRUPT);
>  			if (intr & ONENAND_INT_MASTER)
> @@ -126,7 +140,7 @@ static int omap2_onenand_wait(struct mtd_info *mtd, int state)
>  			wait_err("controller error", state, ctrl, intr);
>  			return -EIO;
>  		}
> -		if (!(intr & ONENAND_INT_RESET)) {
> +		if (!(intr & intr_flags)) {

Since you have OR'd in the ONENAND_INT_MASTER flag, this doesn't check the individual
flags anymore.  Perhaps you want:

+		if ((intr & intr_flags) != intr_flags)) {

>  			wait_err("timeout", state, ctrl, intr);
>  			return -EIO;
>  		}
> diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
> index ce9f9a0..1fa9101 100644
> --- a/drivers/mtd/onenand/onenand_base.c
> +++ b/drivers/mtd/onenand/onenand_base.c
> @@ -32,6 +32,12 @@
>  
>  #include <asm/io.h>
>  
> +/* Multiblock erase if number of blocks to erase is 2 or more.
> +   Maximum number of blocks for simultaneous erase is 64. */

It is more usual to write multiline comments like this:

/*
 * Multiblock erase if number of blocks to erase is 2 or more.
 * Maximum number of blocks for simultaneous erase is 64.
 */

> +#define MB_ERASE_MIN_BLK_COUNT 2
> +#define MB_ERASE_MAX_BLK_COUNT 64
> +
> +
>  /* Default Flex-OneNAND boundary and lock respectively */
>  static int flex_bdry[MAX_DIES * 2] = { -1, 0, -1, 0 };
>  
> @@ -339,6 +345,8 @@ static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
>  		break;
>  
>  	case ONENAND_CMD_ERASE:
> +	case ONENAND_CMD_MULTIBLOCK_ERASE:
> +	case ONENAND_CMD_ERASE_VERIFY:
>  	case ONENAND_CMD_BUFFERRAM:
>  	case ONENAND_CMD_OTP_ACCESS:
>  		block = onenand_block(this, addr);
> @@ -483,7 +491,7 @@ static int onenand_wait(struct mtd_info *mtd, int state)
>  		if (interrupt & flags)
>  			break;
>  
> -		if (state != FL_READING)
> +		if (state != FL_READING && state != FL_PREPARING_ERASE)
>  			cond_resched();
>  	}
>  	/* To get correct interrupt status in timeout case */
> @@ -513,6 +521,18 @@ static int onenand_wait(struct mtd_info *mtd, int state)
>  		return -EIO;
>  	}
>  
> +	if (state == FL_PREPARING_ERASE && !(interrupt & ONENAND_INT_ERASE)) {
> +		printk(KERN_ERR "onenand_wait: mb erase timeout! ctrl=0x%04x intr=0x%04x\n",
> +			ctrl, interrupt);
> +		return -EIO;
> +	}
> +
> +	if (!(interrupt & ONENAND_INT_MASTER)) {
> +		printk(KERN_ERR "onenand_wait: timeout! ctrl=0x%04x intr=0x%04x\n",
> +			ctrl, interrupt);
> +		return -EIO;
> +	}
> +
>  	/* If there's controller error, it's a real error */
>  	if (ctrl & ONENAND_CTRL_ERROR) {
>  		printk(KERN_ERR "onenand_wait: controller error = 0x%04x\n",
> @@ -2140,6 +2160,128 @@ static int onenand_block_isbad_nolock(struct mtd_info *mtd, loff_t ofs, int allo
>  	return bbm->isbad_bbt(mtd, ofs, allowbbt);
>  }
>  
> +
> +static int onenand_multiblock_erase_verify(struct mtd_info *mtd,
> +					   struct erase_info *instr)
> +{
> +	struct onenand_chip *this = mtd->priv;
> +	loff_t addr = instr->addr;
> +	int len = instr->len;
> +	unsigned int block_size = (1 << this->erase_shift);
> +	int ret = 0;
> +
> +	while (len) {
> +		this->command(mtd, ONENAND_CMD_ERASE_VERIFY, addr, block_size);
> +		ret = this->wait(mtd, FL_VERIFYING_ERASE);
> +		if (ret) {
> +			printk(KERN_ERR "onenand_multiblock_erase_verify: "
> +			       "Failed verify, block %d\n", onenand_block(this, addr));
> +			instr->state = MTD_ERASE_FAILED;
> +			instr->fail_addr = addr;
> +			return -1;
> +		}
> +		len -= block_size;
> +		addr += block_size;
> +	}
> +	return 0;
> +}
> +
> +/**
> + * onenand_multiblock_erase - [Internal] erase block(s) using multiblock erase
> + * @param mtd		MTD device structure
> + * @param instr		erase instruction
> + * @param region	erase region
> + *
> + * Erase one or more blocks up to 64 block at a time
> + */
> +static int onenand_multiblock_erase(struct mtd_info *mtd,
> +				    struct erase_info *instr)
> +{
> +	struct onenand_chip *this = mtd->priv;
> +	loff_t addr = instr->addr;
> +	int len = instr->len;
> +	unsigned int block_size = (1 << this->erase_shift);
> +	int eb_count = 0;
> +	int ret = 0;
> +
> +	instr->state = MTD_ERASING;
> +
> +	/* Pre-check bbs */
> +	while (len) {
> +		/* Check if we have a bad block, we do not erase bad blocks */
> +		if (onenand_block_isbad_nolock(mtd, addr, 0)) {
> +			printk(KERN_WARNING "onenand_erase: attempt to erase a bad block at addr 0x%012llx\n", (unsigned long long) addr);
> +			instr->state = MTD_ERASE_FAILED;
> +			return -1;
> +		}
> +		len -= block_size;
> +		addr += block_size;
> +	}
> +
> +	len = instr->len;
> +	addr = instr->addr;
> +
> +
> +	/* loop over 64 eb batches */
> +	while (len) {
> +		struct erase_info verify_instr = *instr;
> +		verify_instr.addr = addr;
> +		verify_instr.len = 0;
> +
> +		eb_count = 0;
> +
> +		while (len > block_size &&
> +		       eb_count < (MB_ERASE_MAX_BLK_COUNT - 1)) {

According to the manual I have you cannot do a multiblock erase
across a chip boundary, so you must exit this loop at the boundary too.

> +			this->command(mtd, ONENAND_CMD_MULTIBLOCK_ERASE, addr, block_size);
> +			onenand_invalidate_bufferram(mtd, addr, block_size);
> +
> +			ret = this->wait(mtd, FL_PREPARING_ERASE);
> +			if (ret) {
> +				printk(KERN_ERR "onenand_multiblock_erase: "
> +				       "Failed multiblock erase, block %d\n",
> +				       onenand_block(this, addr));
> +				instr->state = MTD_ERASE_FAILED;
> +				instr->fail_addr = addr;
> +				return -1;
> +			}
> +
> +			len -= block_size;
> +			addr += block_size;
> +			eb_count++;
> +		}
> +
> +		/* last block of 64-eb series */
> +		cond_resched();
> +		this->command(mtd, ONENAND_CMD_ERASE, addr, block_size);
> +		onenand_invalidate_bufferram(mtd, addr, block_size);
> +
> +		ret = this->wait(mtd, FL_ERASING);
> +		/* Check, if it is write protected */
> +		if (ret) {
> +			printk(KERN_ERR "onenand_erase: Failed erase, block %d\n",
> +			       onenand_block(this, addr));
> +			instr->state = MTD_ERASE_FAILED;
> +			instr->fail_addr = addr;
> +			return -1;
> +		}
> +
> +		len -= block_size;
> +		addr += block_size;
> +		eb_count++;
> +
> +		/* verify */
> +		verify_instr.len = eb_count * block_size;
> +		if (onenand_multiblock_erase_verify(mtd, &verify_instr)) {
> +			instr->state = verify_instr.state;
> +			instr->fail_addr = verify_instr.fail_addr;
> +			return -1;
> +		}
> +
> +	}
> +	return 0;
> +}
> +
> +
>  /**
>   * onenand_single_block_erase - [Internal] erase block(s) using regular erase
>   * @param mtd		MTD device structure
> @@ -2273,7 +2415,12 @@ static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
>  	/* Grab the lock and see if the device is available */
>  	onenand_get_device(mtd, FL_ERASING);
>  
> -	ret = onenand_single_block_erase(mtd, instr, region);
> +	if (region || instr->len < MB_ERASE_MIN_BLK_COUNT * block_size) {
> +		/* region is set for Flex-OneNAND (no mb erase) */
> +		ret = onenand_single_block_erase(mtd, instr, region);
> +	} else {
> +		ret = onenand_multiblock_erase(mtd, instr);
> +	}
>  
>  	if (ret) {
>  		ret = -EIO;
> diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h
> index 8ed8733..42384f3 100644
> --- a/include/linux/mtd/onenand.h
> +++ b/include/linux/mtd/onenand.h
> @@ -39,6 +39,8 @@ typedef enum {
>  	FL_RESETING,
>  	FL_OTPING,
>  	FL_PM_SUSPENDED,
> +	FL_PREPARING_ERASE,
> +	FL_VERIFYING_ERASE

Last one should also have a comma

>  } onenand_state_t;
>  
>  /**
> diff --git a/include/linux/mtd/onenand_regs.h b/include/linux/mtd/onenand_regs.h
> index 86a6bbe..bd346e5 100644
> --- a/include/linux/mtd/onenand_regs.h
> +++ b/include/linux/mtd/onenand_regs.h
> @@ -131,6 +131,8 @@
>  #define ONENAND_CMD_LOCK_TIGHT		(0x2C)
>  #define ONENAND_CMD_UNLOCK_ALL		(0x27)
>  #define ONENAND_CMD_ERASE		(0x94)
> +#define ONENAND_CMD_MULTIBLOCK_ERASE	(0x95)
> +#define ONENAND_CMD_ERASE_VERIFY	(0x71)
>  #define ONENAND_CMD_RESET		(0xF0)
>  #define ONENAND_CMD_OTP_ACCESS		(0x65)
>  #define ONENAND_CMD_READID		(0x90)
Mika Korhonen - Sept. 18, 2009, 5:03 a.m.
Hunter Adrian (Nokia-D/Helsinki) wrote:
> Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
>   
>> Add support for multiblock erase command. OneNANDs (excluding Flex-OneNAND)
>> are capable of simultaneous erase of up to 64 eraseblocks which is much
>> faster.
>> This changes the erase requests for regions covering multiple eraseblocks
>> to be performed using multiblock erase.
>>
>> Signed-off-by: Mika Korhonen <ext-mika.2.korhonen@nokia.com>
>> ---
>>     
>
> A few comments below.
>
>   
[...]
> +		switch (state) {
> +		case FL_RESETING:
> +			intr_flags |= ONENAND_INT_RESET;
> +			break;
> +		case FL_PREPARING_ERASE:
> +			intr_flags |= ONENAND_INT_ERASE;
> +			break;
> +		case FL_VERIFYING_ERASE:
> +			i = 51;
>   
>
> I see 100us for this in some versions.  Perhaps Kyungmin can suggest
> a value.
>   
With the chip I had the actual time for 64-eb verify read was in the 
range of 20-30 us but you're right, there are chips for which the 
maximum time is specified to be 100 us. Is ok to just raise this to that 
value? Kyungmin?

[...]
>
>> +
>> +	/* loop over 64 eb batches */
>> +	while (len) {
>> +		struct erase_info verify_instr = *instr;
>> +		verify_instr.addr = addr;
>> +		verify_instr.len = 0;
>> +
>> +		eb_count = 0;
>> +
>> +		while (len > block_size &&
>> +		       eb_count < (MB_ERASE_MAX_BLK_COUNT - 1)) {
>>     
>
> According to the manual I have you cannot do a multiblock erase
> across a chip boundary, so you must exit this loop at the boundary too.
>   

Ok, does this apply DDP chips only?

br,
Mika
Kyungmin Park - Sept. 18, 2009, 5:38 a.m.
On Fri, Sep 18, 2009 at 2:03 PM, Mika Korhonen
<ext-mika.2.korhonen@nokia.com> wrote:
> Hunter Adrian (Nokia-D/Helsinki) wrote:
>>
>> Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
>>
>>>
>>> Add support for multiblock erase command. OneNANDs (excluding
>>> Flex-OneNAND)
>>> are capable of simultaneous erase of up to 64 eraseblocks which is much
>>> faster.
>>> This changes the erase requests for regions covering multiple eraseblocks
>>> to be performed using multiblock erase.
>>>
>>> Signed-off-by: Mika Korhonen <ext-mika.2.korhonen@nokia.com>
>>> ---
>>>
>>
>> A few comments below.
>>
>>
>
> [...]
>>
>> +               switch (state) {
>> +               case FL_RESETING:
>> +                       intr_flags |= ONENAND_INT_RESET;
>> +                       break;
>> +               case FL_PREPARING_ERASE:
>> +                       intr_flags |= ONENAND_INT_ERASE;
>> +                       break;
>> +               case FL_VERIFYING_ERASE:
>> +                       i = 51;
>>
>> I see 100us for this in some versions.  Perhaps Kyungmin can suggest
>> a value.
>>
>
> With the chip I had the actual time for 64-eb verify read was in the range
> of 20-30 us but you're right, there are chips for which the maximum time is
> specified to be 100 us. Is ok to just raise this to that value? Kyungmin?

To correctness, It should be 100 as Spec.

Just FYI:
In recent OneNAND chips has 4KiB pagesize doesn't support Multi block
erase feature at my spec.

Right, these chips are not yet support at MTD. After make a patch, we
have to check the multi block erase feature.

Thank you,
Kyungmin Park
Adrian Hunter - Sept. 18, 2009, 8:04 a.m.
Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
> Hunter Adrian (Nokia-D/Helsinki) wrote:
>> Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
>>   
>>> Add support for multiblock erase command. OneNANDs (excluding Flex-OneNAND)
>>> are capable of simultaneous erase of up to 64 eraseblocks which is much
>>> faster.
>>> This changes the erase requests for regions covering multiple eraseblocks
>>> to be performed using multiblock erase.
>>>
>>> Signed-off-by: Mika Korhonen <ext-mika.2.korhonen@nokia.com>
>>> ---
>>>     
>> A few comments below.
>>
>>   
> [...]
>> +		switch (state) {
>> +		case FL_RESETING:
>> +			intr_flags |= ONENAND_INT_RESET;
>> +			break;
>> +		case FL_PREPARING_ERASE:
>> +			intr_flags |= ONENAND_INT_ERASE;
>> +			break;
>> +		case FL_VERIFYING_ERASE:
>> +			i = 51;
>>   
>>
>> I see 100us for this in some versions.  Perhaps Kyungmin can suggest
>> a value.
>>   
> With the chip I had the actual time for 64-eb verify read was in the 
> range of 20-30 us but you're right, there are chips for which the 
> maximum time is specified to be 100 us. Is ok to just raise this to that 
> value? Kyungmin?
> 
> [...]
>>> +
>>> +	/* loop over 64 eb batches */
>>> +	while (len) {
>>> +		struct erase_info verify_instr = *instr;
>>> +		verify_instr.addr = addr;
>>> +		verify_instr.len = 0;
>>> +
>>> +		eb_count = 0;
>>> +
>>> +		while (len > block_size &&
>>> +		       eb_count < (MB_ERASE_MAX_BLK_COUNT - 1)) {
>>>     
>> According to the manual I have you cannot do a multiblock erase
>> across a chip boundary, so you must exit this loop at the boundary too.
>>   
> 
> Ok, does this apply DDP chips only?

Yes, AFAIK. Kyungmin?
Kyungmin Park - Sept. 18, 2009, 8:33 a.m.
On Fri, Sep 18, 2009 at 5:04 PM, Adrian Hunter <adrian.hunter@nokia.com> wrote:
> Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
>>
>> Hunter Adrian (Nokia-D/Helsinki) wrote:
>>>
>>> Korhonen Mika.2 (EXT-Ardites/Oulu) wrote:
>>>
>>>>
>>>> Add support for multiblock erase command. OneNANDs (excluding
>>>> Flex-OneNAND)
>>>> are capable of simultaneous erase of up to 64 eraseblocks which is much
>>>> faster.
>>>> This changes the erase requests for regions covering multiple
>>>> eraseblocks
>>>> to be performed using multiblock erase.
>>>>
>>>> Signed-off-by: Mika Korhonen <ext-mika.2.korhonen@nokia.com>
>>>> ---
>>>>
>>>
>>> A few comments below.
>>>
>>>
>>
>> [...]
>>>
>>> +               switch (state) {
>>> +               case FL_RESETING:
>>> +                       intr_flags |= ONENAND_INT_RESET;
>>> +                       break;
>>> +               case FL_PREPARING_ERASE:
>>> +                       intr_flags |= ONENAND_INT_ERASE;
>>> +                       break;
>>> +               case FL_VERIFYING_ERASE:
>>> +                       i = 51;
>>>
>>> I see 100us for this in some versions.  Perhaps Kyungmin can suggest
>>> a value.
>>>
>>
>> With the chip I had the actual time for 64-eb verify read was in the range
>> of 20-30 us but you're right, there are chips for which the maximum time is
>> specified to be 100 us. Is ok to just raise this to that value? Kyungmin?
>>
>> [...]
>>>>
>>>> +
>>>> +       /* loop over 64 eb batches */
>>>> +       while (len) {
>>>> +               struct erase_info verify_instr = *instr;
>>>> +               verify_instr.addr = addr;
>>>> +               verify_instr.len = 0;
>>>> +
>>>> +               eb_count = 0;
>>>> +
>>>> +               while (len > block_size &&
>>>> +                      eb_count < (MB_ERASE_MAX_BLK_COUNT - 1)) {
>>>>
>>>
>>> According to the manual I have you cannot do a multiblock erase
>>> across a chip boundary, so you must exit this loop at the boundary too.
>>>
>>
>> Ok, does this apply DDP chips only?
>
> Yes, AFAIK. Kyungmin?

Of course, Actually DDP has two chips. can't share the info between chips.
That's the reason to check DDP. :)

Thank you,
Kyungmin Park

Patch

diff --git a/drivers/mtd/onenand/omap2.c b/drivers/mtd/onenand/omap2.c
index 0108ed4..47ae815 100644
--- a/drivers/mtd/onenand/omap2.c
+++ b/drivers/mtd/onenand/omap2.c
@@ -112,10 +112,24 @@  static int omap2_onenand_wait(struct mtd_info *mtd, int state)
 	unsigned long timeout;
 	u32 syscfg;
 
-	if (state == FL_RESETING) {
-		int i;
+	if (state == FL_RESETING || state == FL_PREPARING_ERASE ||
+		state == FL_VERIFYING_ERASE) {
+
+		int i = 21;
+		unsigned int intr_flags = ONENAND_INT_MASTER;
+		switch (state) {
+		case FL_RESETING:
+			intr_flags |= ONENAND_INT_RESET;
+			break;
+		case FL_PREPARING_ERASE:
+			intr_flags |= ONENAND_INT_ERASE;
+			break;
+		case FL_VERIFYING_ERASE:
+			i = 51;
+			break;
+		}
 
-		for (i = 0; i < 20; i++) {
+		while (--i) {
 			udelay(1);
 			intr = read_reg(c, ONENAND_REG_INTERRUPT);
 			if (intr & ONENAND_INT_MASTER)
@@ -126,7 +140,7 @@  static int omap2_onenand_wait(struct mtd_info *mtd, int state)
 			wait_err("controller error", state, ctrl, intr);
 			return -EIO;
 		}
-		if (!(intr & ONENAND_INT_RESET)) {
+		if (!(intr & intr_flags)) {
 			wait_err("timeout", state, ctrl, intr);
 			return -EIO;
 		}
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index ce9f9a0..1fa9101 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -32,6 +32,12 @@ 
 
 #include <asm/io.h>
 
+/* Multiblock erase if number of blocks to erase is 2 or more.
+   Maximum number of blocks for simultaneous erase is 64. */
+#define MB_ERASE_MIN_BLK_COUNT 2
+#define MB_ERASE_MAX_BLK_COUNT 64
+
+
 /* Default Flex-OneNAND boundary and lock respectively */
 static int flex_bdry[MAX_DIES * 2] = { -1, 0, -1, 0 };
 
@@ -339,6 +345,8 @@  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 		break;
 
 	case ONENAND_CMD_ERASE:
+	case ONENAND_CMD_MULTIBLOCK_ERASE:
+	case ONENAND_CMD_ERASE_VERIFY:
 	case ONENAND_CMD_BUFFERRAM:
 	case ONENAND_CMD_OTP_ACCESS:
 		block = onenand_block(this, addr);
@@ -483,7 +491,7 @@  static int onenand_wait(struct mtd_info *mtd, int state)
 		if (interrupt & flags)
 			break;
 
-		if (state != FL_READING)
+		if (state != FL_READING && state != FL_PREPARING_ERASE)
 			cond_resched();
 	}
 	/* To get correct interrupt status in timeout case */
@@ -513,6 +521,18 @@  static int onenand_wait(struct mtd_info *mtd, int state)
 		return -EIO;
 	}
 
+	if (state == FL_PREPARING_ERASE && !(interrupt & ONENAND_INT_ERASE)) {
+		printk(KERN_ERR "onenand_wait: mb erase timeout! ctrl=0x%04x intr=0x%04x\n",
+			ctrl, interrupt);
+		return -EIO;
+	}
+
+	if (!(interrupt & ONENAND_INT_MASTER)) {
+		printk(KERN_ERR "onenand_wait: timeout! ctrl=0x%04x intr=0x%04x\n",
+			ctrl, interrupt);
+		return -EIO;
+	}
+
 	/* If there's controller error, it's a real error */
 	if (ctrl & ONENAND_CTRL_ERROR) {
 		printk(KERN_ERR "onenand_wait: controller error = 0x%04x\n",
@@ -2140,6 +2160,128 @@  static int onenand_block_isbad_nolock(struct mtd_info *mtd, loff_t ofs, int allo
 	return bbm->isbad_bbt(mtd, ofs, allowbbt);
 }
 
+
+static int onenand_multiblock_erase_verify(struct mtd_info *mtd,
+					   struct erase_info *instr)
+{
+	struct onenand_chip *this = mtd->priv;
+	loff_t addr = instr->addr;
+	int len = instr->len;
+	unsigned int block_size = (1 << this->erase_shift);
+	int ret = 0;
+
+	while (len) {
+		this->command(mtd, ONENAND_CMD_ERASE_VERIFY, addr, block_size);
+		ret = this->wait(mtd, FL_VERIFYING_ERASE);
+		if (ret) {
+			printk(KERN_ERR "onenand_multiblock_erase_verify: "
+			       "Failed verify, block %d\n", onenand_block(this, addr));
+			instr->state = MTD_ERASE_FAILED;
+			instr->fail_addr = addr;
+			return -1;
+		}
+		len -= block_size;
+		addr += block_size;
+	}
+	return 0;
+}
+
+/**
+ * onenand_multiblock_erase - [Internal] erase block(s) using multiblock erase
+ * @param mtd		MTD device structure
+ * @param instr		erase instruction
+ * @param region	erase region
+ *
+ * Erase one or more blocks up to 64 block at a time
+ */
+static int onenand_multiblock_erase(struct mtd_info *mtd,
+				    struct erase_info *instr)
+{
+	struct onenand_chip *this = mtd->priv;
+	loff_t addr = instr->addr;
+	int len = instr->len;
+	unsigned int block_size = (1 << this->erase_shift);
+	int eb_count = 0;
+	int ret = 0;
+
+	instr->state = MTD_ERASING;
+
+	/* Pre-check bbs */
+	while (len) {
+		/* Check if we have a bad block, we do not erase bad blocks */
+		if (onenand_block_isbad_nolock(mtd, addr, 0)) {
+			printk(KERN_WARNING "onenand_erase: attempt to erase a bad block at addr 0x%012llx\n", (unsigned long long) addr);
+			instr->state = MTD_ERASE_FAILED;
+			return -1;
+		}
+		len -= block_size;
+		addr += block_size;
+	}
+
+	len = instr->len;
+	addr = instr->addr;
+
+
+	/* loop over 64 eb batches */
+	while (len) {
+		struct erase_info verify_instr = *instr;
+		verify_instr.addr = addr;
+		verify_instr.len = 0;
+
+		eb_count = 0;
+
+		while (len > block_size &&
+		       eb_count < (MB_ERASE_MAX_BLK_COUNT - 1)) {
+			this->command(mtd, ONENAND_CMD_MULTIBLOCK_ERASE, addr, block_size);
+			onenand_invalidate_bufferram(mtd, addr, block_size);
+
+			ret = this->wait(mtd, FL_PREPARING_ERASE);
+			if (ret) {
+				printk(KERN_ERR "onenand_multiblock_erase: "
+				       "Failed multiblock erase, block %d\n",
+				       onenand_block(this, addr));
+				instr->state = MTD_ERASE_FAILED;
+				instr->fail_addr = addr;
+				return -1;
+			}
+
+			len -= block_size;
+			addr += block_size;
+			eb_count++;
+		}
+
+		/* last block of 64-eb series */
+		cond_resched();
+		this->command(mtd, ONENAND_CMD_ERASE, addr, block_size);
+		onenand_invalidate_bufferram(mtd, addr, block_size);
+
+		ret = this->wait(mtd, FL_ERASING);
+		/* Check, if it is write protected */
+		if (ret) {
+			printk(KERN_ERR "onenand_erase: Failed erase, block %d\n",
+			       onenand_block(this, addr));
+			instr->state = MTD_ERASE_FAILED;
+			instr->fail_addr = addr;
+			return -1;
+		}
+
+		len -= block_size;
+		addr += block_size;
+		eb_count++;
+
+		/* verify */
+		verify_instr.len = eb_count * block_size;
+		if (onenand_multiblock_erase_verify(mtd, &verify_instr)) {
+			instr->state = verify_instr.state;
+			instr->fail_addr = verify_instr.fail_addr;
+			return -1;
+		}
+
+	}
+	return 0;
+}
+
+
 /**
  * onenand_single_block_erase - [Internal] erase block(s) using regular erase
  * @param mtd		MTD device structure
@@ -2273,7 +2415,12 @@  static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
 	/* Grab the lock and see if the device is available */
 	onenand_get_device(mtd, FL_ERASING);
 
-	ret = onenand_single_block_erase(mtd, instr, region);
+	if (region || instr->len < MB_ERASE_MIN_BLK_COUNT * block_size) {
+		/* region is set for Flex-OneNAND (no mb erase) */
+		ret = onenand_single_block_erase(mtd, instr, region);
+	} else {
+		ret = onenand_multiblock_erase(mtd, instr);
+	}
 
 	if (ret) {
 		ret = -EIO;
diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h
index 8ed8733..42384f3 100644
--- a/include/linux/mtd/onenand.h
+++ b/include/linux/mtd/onenand.h
@@ -39,6 +39,8 @@  typedef enum {
 	FL_RESETING,
 	FL_OTPING,
 	FL_PM_SUSPENDED,
+	FL_PREPARING_ERASE,
+	FL_VERIFYING_ERASE
 } onenand_state_t;
 
 /**
diff --git a/include/linux/mtd/onenand_regs.h b/include/linux/mtd/onenand_regs.h
index 86a6bbe..bd346e5 100644
--- a/include/linux/mtd/onenand_regs.h
+++ b/include/linux/mtd/onenand_regs.h
@@ -131,6 +131,8 @@ 
 #define ONENAND_CMD_LOCK_TIGHT		(0x2C)
 #define ONENAND_CMD_UNLOCK_ALL		(0x27)
 #define ONENAND_CMD_ERASE		(0x94)
+#define ONENAND_CMD_MULTIBLOCK_ERASE	(0x95)
+#define ONENAND_CMD_ERASE_VERIFY	(0x71)
 #define ONENAND_CMD_RESET		(0xF0)
 #define ONENAND_CMD_OTP_ACCESS		(0x65)
 #define ONENAND_CMD_READID		(0x90)