[PATCH v4 0/2] mtd: rawnand: Add support Macronix NAND randomizer

[PATCH v4 0/2] mtd: rawnand: Add support Macronix NAND randomizer

[Mason Yang]

Hi,

changelog
v4:
coding patch & add a new DTS for randomizer enabled.

v3:
To enable randomizer by specific DT property in children nodes,
mxic,enable-randomizer-otp;

v2:
To enable randomizer by checking chip options NAND_NO_SUBPAGE_WRITE

v1:
To enable randomizer by sys-fs

thanks for your time & review.
Mason

Mason Yang (2):
  mtd: rawnand: Add support for Macronix NAND randomizer
  dt-bindings: mtd: Document Macronix NAND device bindings

 .../devicetree/bindings/mtd/nand-macronix.txt      | 20 +++++++
 drivers/mtd/nand/raw/nand_macronix.c               | 69 ++++++++++++++++++++++
 2 files changed, 89 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/nand-macronix.txt

-- 
1.9.1

[PATCH v4 1/2] mtd: rawnand: Add support for Macronix NAND randomizer

[Mason Yang]

Macronix NANDs support randomizer operation for user data scrambled,
which can be enabled with a SET_FEATURE.

User data written to the NAND device without randomizer is still readable
after randomizer function enabled.
The penalty of randomizer are subpage accesses prohibited and more time
period is needed in program operation and entering deep power-down mode.
i.e., tPROG 300us to 340us(randomizer enabled)

For more high-reliability concern, if subpage write not available with
hardware ECC and then to enable randomizer is recommended by default.
Driver checks byte 167 of Vendor Blocks in ONFI parameter page table
to see if this high-reliability function is supported. By adding a new
specific DT property in children nodes to enable randomizer function.

Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
---
 drivers/mtd/nand/raw/nand_macronix.c | 69 ++++++++++++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)

diff --git a/drivers/mtd/nand/raw/nand_macronix.c b/drivers/mtd/nand/raw/nand_macronix.c
index 58511ae..89101fa 100644
--- a/drivers/mtd/nand/raw/nand_macronix.c
+++ b/drivers/mtd/nand/raw/nand_macronix.c
@@ -11,6 +11,14 @@
 #define MACRONIX_READ_RETRY_BIT BIT(0)
 #define MACRONIX_NUM_READ_RETRY_MODES 6
 
+#define MACRONIX_RANDOMIZER_BIT BIT(1)
+#define ONFI_FEATURE_ADDR_MXIC_RANDOMIZER 0xB0
+#define ENPGM BIT(0)
+#define RANDEN BIT(1)
+#define RANDOPT BIT(2)
+#define MACRONIX_RANDOMIZER_MODE_ENTER (ENPGM | RANDEN | RANDOPT)
+#define MACRONIX_RANDOMIZER_MODE_EXIT (RANDEN | RANDOPT)
+
 struct nand_onfi_vendor_macronix {
 	u8 reserved;
 	u8 reliability_func;
@@ -29,15 +37,76 @@ static int macronix_nand_setup_read_retry(struct nand_chip *chip, int mode)
 	return nand_set_features(chip, ONFI_FEATURE_ADDR_READ_RETRY, feature);
 }
 
+static int macronix_nand_randomizer_check_enable(struct nand_chip *chip)
+{
+	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
+	int ret;
+
+	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
+				feature);
+	if (ret < 0)
+		return ret;
+
+	if (feature[0])
+		return feature[0];
+
+	feature[0] = MACRONIX_RANDOMIZER_MODE_ENTER;
+	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
+				feature);
+	if (ret < 0)
+		return ret;
+
+	/* RANDEN and RANDOPT OTP bits are programmed */
+	feature[0] = 0x0;
+	ret = nand_prog_page_op(chip, 0, 0, feature, 1);
+	if (ret < 0)
+		return ret;
+
+	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
+				feature);
+	if (ret < 0)
+		return ret;
+
+	feature[0] &= MACRONIX_RANDOMIZER_MODE_EXIT;
+	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
+				feature);
+	if (ret < 0)
+		return ret;
+
+	return feature[0];
+}
+
 static void macronix_nand_onfi_init(struct nand_chip *chip)
 {
 	struct nand_parameters *p = &chip->parameters;
 	struct nand_onfi_vendor_macronix *mxic;
+	struct device_node *dn = nand_get_flash_node(chip);
+	int rand_otp = 0;
+	int ret;
 
 	if (!p->onfi)
 		return;
 
+	if (of_find_property(dn, "mxic,enable-randomizer-otp", NULL))
+		rand_otp = 1;
+
 	mxic = (struct nand_onfi_vendor_macronix *)p->onfi->vendor;
+	/* Subpage write is prohibited in randomizer operatoin */
+	if (rand_otp && chip->options & NAND_NO_SUBPAGE_WRITE &&
+	    mxic->reliability_func & MACRONIX_RANDOMIZER_BIT) {
+		if (p->supports_set_get_features) {
+			bitmap_set(p->set_feature_list,
+				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
+			bitmap_set(p->get_feature_list,
+				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
+			ret = macronix_nand_randomizer_check_enable(chip);
+			if (ret < 0)
+				pr_info("Macronix NAND randomizer failed\n");
+			else
+				pr_info("Macronix NAND randomizer enabled\n");
+		}
+	}
+
 	if ((mxic->reliability_func & MACRONIX_READ_RETRY_BIT) == 0)
 		return;
 
-- 
1.9.1

[PATCH v4 2/2] dt-bindings: mtd: Document Macronix NAND device bindings

[Mason Yang]

Document the bindings used by the Macronix NAND device.

Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
---
 .../devicetree/bindings/mtd/nand-macronix.txt        | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/nand-macronix.txt

diff --git a/Documentation/devicetree/bindings/mtd/nand-macronix.txt b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
new file mode 100644
index 0000000..cb60358
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
@@ -0,0 +1,20 @@
+Macronix NANDs Device Tree Bindings
+-----------------------------------
+
+Macronix NANDs support randomizer operation for user data scrambled,
+which can be enabled with a SET_FEATURE. The penalty of randomizer
+is subpage accesses prohibited. By adding a new specific property
+in children nodes to enable randomizer function.
+
+Required NAND chip properties in children mode:
+- randomizer enable: should be "mxic,enable-randomizer-otp"
+
+Example:
+
+	nand: nand-controller@unit-address {
+
+		nand@0 {
+			reg = <0>;
+			mxic,enable-randomizer-otp;
+		};
+	};
-- 
1.9.1

Re: [PATCH v4 2/2] dt-bindings: mtd: Document Macronix NAND device bindings

[Rob Herring]

On Thu, 24 Oct 2019 15:40:07 +0800, Mason Yang wrote:
> Document the bindings used by the Macronix NAND device.
> 
> Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
> ---
>  .../devicetree/bindings/mtd/nand-macronix.txt        | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mtd/nand-macronix.txt
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v4 1/2] mtd: rawnand: Add support for Macronix NAND randomizer

[Miquel Raynal]

Hi Mason,

Mason Yang <masonccyang@mxic.com.tw> wrote on Thu, 24 Oct 2019 15:40:06
+0800:

> Macronix NANDs support randomizer operation for user data scrambled,
> which can be enabled with a SET_FEATURE.
> 
> User data written to the NAND device without randomizer is still readable
> after randomizer function enabled.
> The penalty of randomizer are subpage accesses prohibited and more time
> period is needed in program operation and entering deep power-down mode.
> i.e., tPROG 300us to 340us(randomizer enabled)
> 
> For more high-reliability concern, if subpage write not available with
> hardware ECC and then to enable randomizer is recommended by default.
> Driver checks byte 167 of Vendor Blocks in ONFI parameter page table
> to see if this high-reliability function is supported. By adding a new
> specific DT property in children nodes to enable randomizer function.
> 
> Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
> ---
>  drivers/mtd/nand/raw/nand_macronix.c | 69 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 69 insertions(+)
> 
> diff --git a/drivers/mtd/nand/raw/nand_macronix.c b/drivers/mtd/nand/raw/nand_macronix.c
> index 58511ae..89101fa 100644
> --- a/drivers/mtd/nand/raw/nand_macronix.c
> +++ b/drivers/mtd/nand/raw/nand_macronix.c
> @@ -11,6 +11,14 @@
>  #define MACRONIX_READ_RETRY_BIT BIT(0)
>  #define MACRONIX_NUM_READ_RETRY_MODES 6
>  
> +#define MACRONIX_RANDOMIZER_BIT BIT(1)
> +#define ONFI_FEATURE_ADDR_MXIC_RANDOMIZER 0xB0
> +#define ENPGM BIT(0)
> +#define RANDEN BIT(1)
> +#define RANDOPT BIT(2)
> +#define MACRONIX_RANDOMIZER_MODE_ENTER (ENPGM | RANDEN | RANDOPT)
> +#define MACRONIX_RANDOMIZER_MODE_EXIT (RANDEN | RANDOPT)
> +
>  struct nand_onfi_vendor_macronix {
>  	u8 reserved;
>  	u8 reliability_func;
> @@ -29,15 +37,76 @@ static int macronix_nand_setup_read_retry(struct nand_chip *chip, int mode)
>  	return nand_set_features(chip, ONFI_FEATURE_ADDR_READ_RETRY, feature);
>  }
>  
> +static int macronix_nand_randomizer_check_enable(struct nand_chip *chip)
> +{
> +	u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
> +	int ret;
> +
> +	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> +				feature);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (feature[0])
> +		return feature[0];
> +
> +	feature[0] = MACRONIX_RANDOMIZER_MODE_ENTER;
> +	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> +				feature);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* RANDEN and RANDOPT OTP bits are programmed */
> +	feature[0] = 0x0;
> +	ret = nand_prog_page_op(chip, 0, 0, feature, 1);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> +				feature);
> +	if (ret < 0)
> +		return ret;
> +
> +	feature[0] &= MACRONIX_RANDOMIZER_MODE_EXIT;
> +	ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> +				feature);
> +	if (ret < 0)
> +		return ret;
> +
> +	return feature[0];

Can feature[0] be != 0 ? I don't think so, in this case I prefer a:
return 0;

> +}
> +
>  static void macronix_nand_onfi_init(struct nand_chip *chip)
>  {
>  	struct nand_parameters *p = &chip->parameters;
>  	struct nand_onfi_vendor_macronix *mxic;
> +	struct device_node *dn = nand_get_flash_node(chip);
> +	int rand_otp = 0;
> +	int ret;
>  
>  	if (!p->onfi)
>  		return;
>  
> +	if (of_find_property(dn, "mxic,enable-randomizer-otp", NULL))
> +		rand_otp = 1;
> +
>  	mxic = (struct nand_onfi_vendor_macronix *)p->onfi->vendor;
> +	/* Subpage write is prohibited in randomizer operatoin */

                                       with          operation

> +	if (rand_otp && chip->options & NAND_NO_SUBPAGE_WRITE &&
> +	    mxic->reliability_func & MACRONIX_RANDOMIZER_BIT) {
> +		if (p->supports_set_get_features) {
> +			bitmap_set(p->set_feature_list,
> +				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> +			bitmap_set(p->get_feature_list,
> +				   ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> +			ret = macronix_nand_randomizer_check_enable(chip);
> +			if (ret < 0)
> +				pr_info("Macronix NAND randomizer failed\n");
> +			else
> +				pr_info("Macronix NAND randomizer enabled\n");

Maybe we should update the bitmaps only if it succeeds?

> +		}
> +	}
> +
>  	if ((mxic->reliability_func & MACRONIX_READ_RETRY_BIT) == 0)
>  		return;
>  

With the above fixed,
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>

Thanks,
Miquèl

Re: [PATCH v4 2/2] dt-bindings: mtd: Document Macronix NAND device bindings

[Miquel Raynal]

Hi Mason,

Mason Yang <masonccyang@mxic.com.tw> wrote on Thu, 24 Oct 2019 15:40:07
+0800:

> Document the bindings used by the Macronix NAND device.
> 
> Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
> ---
>  .../devicetree/bindings/mtd/nand-macronix.txt        | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mtd/nand-macronix.txt
> 
> diff --git a/Documentation/devicetree/bindings/mtd/nand-macronix.txt b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
> new file mode 100644
> index 0000000..cb60358
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
> @@ -0,0 +1,20 @@
> +Macronix NANDs Device Tree Bindings
> +-----------------------------------
> +
> +Macronix NANDs support randomizer operation for user data scrambled,
> +which can be enabled with a SET_FEATURE. The penalty of randomizer
> +is subpage accesses prohibited. By adding a new specific property
> +in children nodes to enable randomizer function.

You don't mention the performance penalty nor the benefits of such
operation.

Please also insist on the fact that this is a one time persistent, non
reversible operation and the use should use this property only if they
know what they are doing!

> +
> +Required NAND chip properties in children mode:
> +- randomizer enable: should be "mxic,enable-randomizer-otp"
> +
> +Example:
> +
> +	nand: nand-controller@unit-address {
> +
> +		nand@0 {
> +			reg = <0>;
> +			mxic,enable-randomizer-otp;
> +		};
> +	};

Thanks,
Miquèl

Re: [PATCH v4 1/2] mtd: rawnand: Add support for Macronix NAND randomizer

[Miquel Raynal]

Hi Mason,

Mason Yang <masonccyang@mxic.com.tw> wrote on Thu, 24 Oct 2019 15:40:06
+0800:

> Macronix NANDs support randomizer operation for user data scrambled,
> which can be enabled with a SET_FEATURE.
> 
> User data written to the NAND device without randomizer is still readable
> after randomizer function enabled.
> The penalty of randomizer are subpage accesses prohibited and more time
> period is needed in program operation and entering deep power-down mode.
> i.e., tPROG 300us to 340us(randomizer enabled)
> 
> For more high-reliability concern, if subpage write not available with
> hardware ECC and then to enable randomizer is recommended by default.
> Driver checks byte 167 of Vendor Blocks in ONFI parameter page table
> to see if this high-reliability function is supported. By adding a new
> specific DT property in children nodes to enable randomizer function.
> 
> Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
> ---
>  drivers/mtd/nand/raw/nand_macronix.c | 69 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 69 insertions(+)
> 
> diff --git a/drivers/mtd/nand/raw/nand_macronix.c b/drivers/mtd/nand/raw/nand_macronix.c
> index 58511ae..89101fa 100644
> --- a/drivers/mtd/nand/raw/nand_macronix.c
> +++ b/drivers/mtd/nand/raw/nand_macronix.c
> @@ -11,6 +11,14 @@
>  #define MACRONIX_READ_RETRY_BIT BIT(0)
>  #define MACRONIX_NUM_READ_RETRY_MODES 6
>  
> +#define MACRONIX_RANDOMIZER_BIT BIT(1)
> +#define ONFI_FEATURE_ADDR_MXIC_RANDOMIZER 0xB0
> +#define ENPGM BIT(0)
> +#define RANDEN BIT(1)
> +#define RANDOPT BIT(2)

I forgot: please be consistent with the naming.

Thanks,
Miquèl

Re: [PATCH v4 1/2] mtd: rawnand: Add support for Macronix NAND randomizer

[masonccyang]

Hi Miquel,


> >  drivers/mtd/nand/raw/nand_macronix.c | 69 
++++++++++++++++++++++++++++++++++++
> >  1 file changed, 69 insertions(+)
> > 
> > diff --git a/drivers/mtd/nand/raw/nand_macronix.c 
b/drivers/mtd/nand/raw/
> nand_macronix.c
> > index 58511ae..89101fa 100644
> > --- a/drivers/mtd/nand/raw/nand_macronix.c
> > +++ b/drivers/mtd/nand/raw/nand_macronix.c
> > @@ -11,6 +11,14 @@
> >  #define MACRONIX_READ_RETRY_BIT BIT(0)
> >  #define MACRONIX_NUM_READ_RETRY_MODES 6
> > 
> > +#define MACRONIX_RANDOMIZER_BIT BIT(1)
> > +#define ONFI_FEATURE_ADDR_MXIC_RANDOMIZER 0xB0
> > +#define ENPGM BIT(0)
> > +#define RANDEN BIT(1)
> > +#define RANDOPT BIT(2)
> 
> I forgot: please be consistent with the naming.

okay, will fix them to

#define MACRONIX_RANDOMIZER_ENPGM BIT(0)
#define MACRONIX_RANDOMIZER_RANDEN BIT(1)
#define MACRONIX_RANDOMIZER_RANDOPT BIT(2)

thanks for your time & comments.
Mason


CONFIDENTIALITY NOTE:

This e-mail and any attachments may contain confidential information 
and/or personal data, which is protected by applicable laws. Please be 
reminded that duplication, disclosure, distribution, or use of this e-mail 
(and/or its attachments) or any part thereof is prohibited. If you receive 
this e-mail in error, please notify us immediately and delete this mail as 
well as its attachment(s) from your system. In addition, please be 
informed that collection, processing, and/or use of personal data is 
prohibited unless expressly permitted by personal data protection laws. 
Thank you for your attention and cooperation.

Macronix International Co., Ltd.

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



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

CONFIDENTIALITY NOTE:

This e-mail and any attachments may contain confidential information and/or personal data, which is protected by applicable laws. Please be reminded that duplication, disclosure, distribution, or use of this e-mail (and/or its attachments) or any part thereof is prohibited. If you receive this e-mail in error, please notify us immediately and delete this mail as well as its attachment(s) from your system. In addition, please be informed that collection, processing, and/or use of personal data is prohibited unless expressly permitted by personal data protection laws. Thank you for your attention and cooperation.

Macronix International Co., Ltd.

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

Re: [PATCH v4 1/2] mtd: rawnand: Add support for Macronix NAND randomizer

[masonccyang]

Hi Miquel,

 
> > +static int macronix_nand_randomizer_check_enable(struct nand_chip 
*chip)
> > +{
> > +   u8 feature[ONFI_SUBFEATURE_PARAM_LEN];
> > +   int ret;
> > +
> > +   ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> > +            feature);
> > +   if (ret < 0)
> > +      return ret;
> > +
> > +   if (feature[0])
> > +      return feature[0];
> > +
> > +   feature[0] = MACRONIX_RANDOMIZER_MODE_ENTER;
> > +   ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> > +            feature);
> > +   if (ret < 0)
> > +      return ret;
> > +
> > +   /* RANDEN and RANDOPT OTP bits are programmed */
> > +   feature[0] = 0x0;
> > +   ret = nand_prog_page_op(chip, 0, 0, feature, 1);
> > +   if (ret < 0)
> > +      return ret;
> > +
> > +   ret = nand_get_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> > +            feature);
> > +   if (ret < 0)
> > +      return ret;
> > +
> > +   feature[0] &= MACRONIX_RANDOMIZER_MODE_EXIT;
> > +   ret = nand_set_features(chip, ONFI_FEATURE_ADDR_MXIC_RANDOMIZER,
> > +            feature);
> > +   if (ret < 0)
> > +      return ret;
> > +
> > +   return feature[0];
> 
> Can feature[0] be != 0 ? I don't think so, in this case I prefer a:
> return 0;
> 

okay, will fix it.

> > +}
> > +
> >  static void macronix_nand_onfi_init(struct nand_chip *chip)
> >  {
> >     struct nand_parameters *p = &chip->parameters;
> >     struct nand_onfi_vendor_macronix *mxic;
> > +   struct device_node *dn = nand_get_flash_node(chip);
> > +   int rand_otp = 0;
> > +   int ret;
> > 
> >     if (!p->onfi)
> >        return;
> > 
> > +   if (of_find_property(dn, "mxic,enable-randomizer-otp", NULL))
> > +      rand_otp = 1;
> > +
> >     mxic = (struct nand_onfi_vendor_macronix *)p->onfi->vendor;
> > +   /* Subpage write is prohibited in randomizer operatoin */
> 
>                                        with          operation
> 
> > +   if (rand_otp && chip->options & NAND_NO_SUBPAGE_WRITE &&
> > +       mxic->reliability_func & MACRONIX_RANDOMIZER_BIT) {
> > +      if (p->supports_set_get_features) {
> > +         bitmap_set(p->set_feature_list,
> > +               ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> > +         bitmap_set(p->get_feature_list,
> > +               ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> > +         ret = macronix_nand_randomizer_check_enable(chip);
> > +         if (ret < 0)
> > +            pr_info("Macronix NAND randomizer failed\n");
> > +         else
> > +            pr_info("Macronix NAND randomizer enabled\n");
> 
> Maybe we should update the bitmaps only if it succeeds?

okay, will drop pr_info();

> 
> > +      }
> > +   }
> > +
> >     if ((mxic->reliability_func & MACRONIX_READ_RETRY_BIT) == 0)
> >        return;
> > 
> 
> With the above fixed,
> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
> 
> Thanks,
> Miquèl

thanks for your time & comments.
Mason

CONFIDENTIALITY NOTE:

This e-mail and any attachments may contain confidential information 
and/or personal data, which is protected by applicable laws. Please be 
reminded that duplication, disclosure, distribution, or use of this e-mail 
(and/or its attachments) or any part thereof is prohibited. If you receive 
this e-mail in error, please notify us immediately and delete this mail as 
well as its attachment(s) from your system. In addition, please be 
informed that collection, processing, and/or use of personal data is 
prohibited unless expressly permitted by personal data protection laws. 
Thank you for your attention and cooperation.

Macronix International Co., Ltd.

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



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

CONFIDENTIALITY NOTE:

This e-mail and any attachments may contain confidential information and/or personal data, which is protected by applicable laws. Please be reminded that duplication, disclosure, distribution, or use of this e-mail (and/or its attachments) or any part thereof is prohibited. If you receive this e-mail in error, please notify us immediately and delete this mail as well as its attachment(s) from your system. In addition, please be informed that collection, processing, and/or use of personal data is prohibited unless expressly permitted by personal data protection laws. Thank you for your attention and cooperation.

Macronix International Co., Ltd.

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

Re: [PATCH v4 1/2] mtd: rawnand: Add support for Macronix NAND randomizer

[Miquel Raynal]

Hi Mason,

> > > +}
> > > +
> > >  static void macronix_nand_onfi_init(struct nand_chip *chip)
> > >  {
> > >     struct nand_parameters *p = &chip->parameters;
> > >     struct nand_onfi_vendor_macronix *mxic;
> > > +   struct device_node *dn = nand_get_flash_node(chip);
> > > +   int rand_otp = 0;
> > > +   int ret;
> > > 
> > >     if (!p->onfi)
> > >        return;
> > > 
> > > +   if (of_find_property(dn, "mxic,enable-randomizer-otp", NULL))
> > > +      rand_otp = 1;
> > > +
> > >     mxic = (struct nand_onfi_vendor_macronix *)p->onfi->vendor;
> > > +   /* Subpage write is prohibited in randomizer operatoin */  
> > 
> >                                        with          operation
> >   
> > > +   if (rand_otp && chip->options & NAND_NO_SUBPAGE_WRITE &&
> > > +       mxic->reliability_func & MACRONIX_RANDOMIZER_BIT) {
> > > +      if (p->supports_set_get_features) {
> > > +         bitmap_set(p->set_feature_list,
> > > +               ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> > > +         bitmap_set(p->get_feature_list,
> > > +               ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> > > +         ret = macronix_nand_randomizer_check_enable(chip);
> > > +         if (ret < 0)
> > > +            pr_info("Macronix NAND randomizer failed\n");
> > > +         else
> > > +            pr_info("Macronix NAND randomizer enabled\n");  
> > 
> > Maybe we should update the bitmaps only if it succeeds?  
> 
> okay, will drop pr_info();

It's not my point, you can keep the pr_info, I just say that you should
check ret before updating the bitmap maybe? Otherwise if
macronix_nand_randomizer_check_enable() fails, you end up without the
feature but with its bit set in the bitmap.

Thanks,
Miquèl

Re: [PATCH v4 1/2] mtd: rawnand: Add support for Macronix NAND randomizer

[masonccyang]

Hi Miquel,

> > > > +}
> > > > +
> > > >  static void macronix_nand_onfi_init(struct nand_chip *chip)
> > > >  {
> > > >     struct nand_parameters *p = &chip->parameters;
> > > >     struct nand_onfi_vendor_macronix *mxic;
> > > > +   struct device_node *dn = nand_get_flash_node(chip);
> > > > +   int rand_otp = 0;
> > > > +   int ret;
> > > > 
> > > >     if (!p->onfi)
> > > >        return;
> > > > 
> > > > +   if (of_find_property(dn, "mxic,enable-randomizer-otp", NULL))
> > > > +      rand_otp = 1;
> > > > +
> > > >     mxic = (struct nand_onfi_vendor_macronix *)p->onfi->vendor;
> > > > +   /* Subpage write is prohibited in randomizer operatoin */ 
> > > 
> > >                                        with          operation
> > > 
> > > > +   if (rand_otp && chip->options & NAND_NO_SUBPAGE_WRITE &&
> > > > +       mxic->reliability_func & MACRONIX_RANDOMIZER_BIT) {
> > > > +      if (p->supports_set_get_features) {
> > > > +         bitmap_set(p->set_feature_list,
> > > > +               ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> > > > +         bitmap_set(p->get_feature_list,
> > > > +               ONFI_FEATURE_ADDR_MXIC_RANDOMIZER, 1);
> > > > +         ret = macronix_nand_randomizer_check_enable(chip);
> > > > +         if (ret < 0)
> > > > +            pr_info("Macronix NAND randomizer failed\n");
> > > > +         else
> > > > +            pr_info("Macronix NAND randomizer enabled\n"); 
> > > 
> > > Maybe we should update the bitmaps only if it succeeds? 
> > 
> > okay, will drop pr_info();
> 
> It's not my point, you can keep the pr_info, I just say that you should
> check ret before updating the bitmap maybe? Otherwise if
> macronix_nand_randomizer_check_enable() fails, you end up without the
> feature but with its bit set in the bitmap.

Driver should set ONFI_FEATURE_ADDR_MXIC_RANDOMIZER in 
p->set/get_feature_list
before calling macronix_nand_randomizer_check_enable() for randomizer 
set/get
feature operation.

I will patch bitmap_clear() if macronix_nand_randomizer_check_enable() 
return fails.

thanks for your time & comments.
Mason


CONFIDENTIALITY NOTE:

This e-mail and any attachments may contain confidential information 
and/or personal data, which is protected by applicable laws. Please be 
reminded that duplication, disclosure, distribution, or use of this e-mail 
(and/or its attachments) or any part thereof is prohibited. If you receive 
this e-mail in error, please notify us immediately and delete this mail as 
well as its attachment(s) from your system. In addition, please be 
informed that collection, processing, and/or use of personal data is 
prohibited unless expressly permitted by personal data protection laws. 
Thank you for your attention and cooperation.

Macronix International Co., Ltd.

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



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

CONFIDENTIALITY NOTE:

This e-mail and any attachments may contain confidential information and/or personal data, which is protected by applicable laws. Please be reminded that duplication, disclosure, distribution, or use of this e-mail (and/or its attachments) or any part thereof is prohibited. If you receive this e-mail in error, please notify us immediately and delete this mail as well as its attachment(s) from your system. In addition, please be informed that collection, processing, and/or use of personal data is prohibited unless expressly permitted by personal data protection laws. Thank you for your attention and cooperation.

Macronix International Co., Ltd.

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