[PATCH v9 0/3] mtd: spi-nand: Add support for randomizer feature

[PATCH v9 0/3] mtd: spi-nand: Add support for randomizer feature

[Cheng Ming Lin]

From: Cheng Ming Lin <chengminglin@mxic.com.tw>

This patch series introduces randomizer support for SPI NAND devices.

- Patch 1: add the nand-randomizer property to the generic nand-chip.yaml
           bindings. Instead of using boolean properties, it introduces a
           uint32 enum (0 or 1). If the property is omitted, the driver
           will not interfere and will leave the randomizer in its current
           state.
- Patch 2: add the initialization logic and the set_randomizer callback
           to the core framework. The core will now parse the device tree
           properties and enable or disable the randomizer accordingly
           during spinand_init.
- Patch 3: implement the set_randomizer callback specifically for Macronix
           chips (MX35LF/UF series) to handle the vendor-specific register
           operations.

v9:
* Replaced 'nand-enable-randomizer'/'nand-disable-randomizer'
  boolean properties with a single 'nand-randomizer' uint32 enum.
* Switched to use of_property_read_u32() to align with the new
  binding.

v8:
* dt-bindings: spi-nand: macronix: Remove the chip-specific Application
  Note link from the commit message to keep the binding generic.
* mtd: spi-nand: macronix: Update the broken Application Note link and
  move it here from the dt-binding patch per Miquel's suggestion.

v7:
* Directly return the result in macronix_set_randomizer()

v6:
* Added mutual-exclusive constraints using not with required for
  nand-randomizer-enable and nand-randomizer-disable properties based
  on Krzysztof's feedback.
* Simplified the return path in macronix_set_randomizer() to directly
  return ret; and dropped unrelated formatting changes.

v5:
* Promoted the randomizer configuration to use generic NAND properties
  (nand-randomizer-enable and nand-randomizer-disable) instead of
  vendor-specific bindings.
* Refactored the initialization architecture in core.c. The core framework
  is now responsible for parsing the device tree properties and deciding
  whether to enable or disable the randomizer.

v4:
* Fix a build error in spinand_randomizer_init() where a value was
  returned from a void function. (Reported by kernel test robot)
* Update the return type to int.

v3:
* Revert the device tree property to the vendor-specific
  "mxic,randomizer-enable" to strictly follow vendor-specific bindings.

* Update the 'set_randomizer' callback signature to accept a boolean
  'enable' argument, allowing the feature to be explicitly enabled or
  disabled.

* Switch the implementation to use the standard SET_FEATURE command
  to modify the Configuration Register (0x10), replacing the previous
  special program command method.

v2:
* Create a global NAND DT property

Cheng Ming Lin (3):
  dt-bindings: mtd: nand: Add nand-randomizer property
  mtd: spi-nand: Add support for randomizer
  mtd: spi-nand: macronix: Enable randomizer support

 .../devicetree/bindings/mtd/nand-chip.yaml    |  9 +++++
 drivers/mtd/nand/spi/core.c                   | 20 ++++++++++
 drivers/mtd/nand/spi/macronix.c               | 38 ++++++++++++++-----
 include/linux/mtd/spinand.h                   |  9 +++++
 4 files changed, 66 insertions(+), 10 deletions(-)

-- 
2.25.1


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[PATCH v9 1/3] dt-bindings: mtd: nand: Add nand-randomizer property

[Cheng Ming Lin]

From: Cheng Ming Lin <chengminglin@mxic.com.tw>

Add the 'nand-randomizer' property to control the data randomizer
feature. This is used to improve data reliability by reducing
cell-to-cell interference.

Depending on the hardware architecture, this property is designed to be
generic and can apply to either the NAND chip's internal randomizer
or the hardware randomizer engine embedded in the NAND host controller.

This property is defined as a uint32 enum (0 or 1) instead of a simple
boolean. This design choice explicitly supports the "not present" case.
If the property is omitted, the driver will not interfere and will leave
the randomizer in its current state (e.g., as already configured by the
bootloader or hardware default).

Signed-off-by: Cheng Ming Lin <chengminglin@mxic.com.tw>
---
 Documentation/devicetree/bindings/mtd/nand-chip.yaml | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/mtd/nand-chip.yaml b/Documentation/devicetree/bindings/mtd/nand-chip.yaml
index 8800d1d07..effdc4f99 100644
--- a/Documentation/devicetree/bindings/mtd/nand-chip.yaml
+++ b/Documentation/devicetree/bindings/mtd/nand-chip.yaml
@@ -23,6 +23,15 @@ properties:
     description:
       Contains the chip-select IDs.
 
+  nand-randomizer:
+    description: |
+      Control the data randomizer feature.
+      0: Disable randomizer.
+      1: Enable randomizer.
+      If absent, the current hardware state is left unchanged.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [0, 1]
+
 required:
   - reg
 
-- 
2.25.1


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[PATCH v9 2/3] mtd: spi-nand: Add support for randomizer

[Cheng Ming Lin]

From: Cheng Ming Lin <chengminglin@mxic.com.tw>

This patch adds support for the randomizer feature.

It introduces a 'set_randomizer' callback in 'struct spinand_info' and
'struct spinand_device'.

If a driver implements this callback, the core will invoke it during
device initialization (spinand_init) to enable or disable the randomizer
feature based on the device tree configuration.

Signed-off-by: Cheng Ming Lin <chengminglin@mxic.com.tw>
---
 drivers/mtd/nand/spi/core.c | 20 ++++++++++++++++++++
 include/linux/mtd/spinand.h |  9 +++++++++
 2 files changed, 29 insertions(+)

diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 8aa3753aa..fee9a024d 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -1307,6 +1307,22 @@ static int spinand_create_dirmaps(struct spinand_device *spinand)
 	return 0;
 }
 
+static int spinand_randomizer_init(struct spinand_device *spinand)
+{
+	struct device_node *np = spinand->spimem->spi->dev.of_node;
+	u32 rand_val;
+	int ret;
+
+	if (!spinand->set_randomizer)
+		return 0;
+
+	ret = of_property_read_u32(np, "nand-randomizer", &rand_val);
+	if (ret)
+		return 0;
+
+	return spinand->set_randomizer(spinand, rand_val == 1);
+}
+
 static const struct nand_ops spinand_ops = {
 	.erase = spinand_erase,
 	.markbad = spinand_markbad,
@@ -1594,6 +1610,7 @@ int spinand_match_and_init(struct spinand_device *spinand,
 		spinand->user_otp = &table[i].user_otp;
 		spinand->read_retries = table[i].read_retries;
 		spinand->set_read_retry = table[i].set_read_retry;
+		spinand->set_randomizer = table[i].set_randomizer;
 
 		/* I/O variants selection with single-spi SDR commands */
 
@@ -1881,6 +1898,9 @@ static int spinand_init(struct spinand_device *spinand)
 	 * ECC initialization must have happened previously.
 	 */
 	spinand_cont_read_init(spinand);
+	ret = spinand_randomizer_init(spinand);
+	if (ret)
+		goto err_cleanup_nanddev;
 
 	mtd->_read_oob = spinand_mtd_read;
 	mtd->_write_oob = spinand_mtd_write;
diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
index 58abd306e..9ec45b727 100644
--- a/include/linux/mtd/spinand.h
+++ b/include/linux/mtd/spinand.h
@@ -585,6 +585,7 @@ enum spinand_bus_interface {
  * @user_otp: SPI NAND user OTP info.
  * @read_retries: the number of read retry modes supported
  * @set_read_retry: enable/disable read retry for data recovery
+ * @set_randomizer: enable/disable randomizer support
  *
  * Each SPI NAND manufacturer driver should have a spinand_info table
  * describing all the chips supported by the driver.
@@ -613,6 +614,8 @@ struct spinand_info {
 	unsigned int read_retries;
 	int (*set_read_retry)(struct spinand_device *spinand,
 			     unsigned int read_retry);
+	int (*set_randomizer)(struct spinand_device *spinand,
+			      bool enable);
 };
 
 #define SPINAND_ID(__method, ...)					\
@@ -669,6 +672,9 @@ struct spinand_info {
 	.read_retries = __read_retries,					\
 	.set_read_retry = __set_read_retry
 
+#define SPINAND_RANDOMIZER(__set_randomizer)				\
+	.set_randomizer = __set_randomizer
+
 #define SPINAND_INFO(__model, __id, __memorg, __eccreq, __op_variants,	\
 		     __flags, ...)					\
 	{								\
@@ -754,6 +760,7 @@ struct spinand_mem_ops {
  * @user_otp: SPI NAND user OTP info.
  * @read_retries: the number of read retry modes supported
  * @set_read_retry: Enable/disable the read retry feature
+ * @set_randomizer: Enable/disable the randomizer feature
  */
 struct spinand_device {
 	struct nand_device base;
@@ -787,6 +794,8 @@ struct spinand_device {
 	bool cont_read_possible;
 	int (*set_cont_read)(struct spinand_device *spinand,
 			     bool enable);
+	int (*set_randomizer)(struct spinand_device *spinand,
+			      bool enable);
 
 	const struct spinand_fact_otp *fact_otp;
 	const struct spinand_user_otp *user_otp;
-- 
2.25.1


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[PATCH v9 3/3] mtd: spi-nand: macronix: Enable randomizer support

[Cheng Ming Lin]

From: Cheng Ming Lin <chengminglin@mxic.com.tw>

Implement the 'set_randomizer' callback for Macronix SPI NAND chips.
The randomizer is enabled by setting bit 1 of the Configuration Register
(address 0x10).

This patch adds support for the following chips:
  - MX35LFxG24AD series
  - MX35UFxG24AD series

When the randomizer is enabled, data is scrambled internally during
program operations and automatically descrambled during read operations.
This helps reduce bit errors caused by program disturbance.

Please refer to the following link for randomizer feature:
Link: https://www.mxic.com.tw/Lists/ApplicationNote/Attachments/2151/AN1051V1-The%20Introduction%20of%20Randomizer%20Feature%20on%20MX30xFxG28AD_MX35xFxG24AD.pdf

Signed-off-by: Cheng Ming Lin <chengminglin@mxic.com.tw>
---
 drivers/mtd/nand/spi/macronix.c | 38 ++++++++++++++++++++++++---------
 1 file changed, 28 insertions(+), 10 deletions(-)

diff --git a/drivers/mtd/nand/spi/macronix.c b/drivers/mtd/nand/spi/macronix.c
index 67cafa1bb..7dfcc34e9 100644
--- a/drivers/mtd/nand/spi/macronix.c
+++ b/drivers/mtd/nand/spi/macronix.c
@@ -14,6 +14,8 @@
 #define MACRONIX_ECCSR_BF_LAST_PAGE(eccsr) FIELD_GET(GENMASK(3, 0), eccsr)
 #define MACRONIX_ECCSR_BF_ACCUMULATED_PAGES(eccsr) FIELD_GET(GENMASK(7, 4), eccsr)
 #define MACRONIX_CFG_CONT_READ         BIT(2)
+#define MACRONIX_CFG_RANDOMIZER_EN     BIT(1)
+#define MACRONIX_FEATURE_ADDR_RANDOMIZER 0x10
 #define MACRONIX_FEATURE_ADDR_READ_RETRY 0x70
 #define MACRONIX_NUM_READ_RETRY_MODES 5
 
@@ -170,6 +172,12 @@ static int macronix_set_read_retry(struct spinand_device *spinand,
 	return spi_mem_exec_op(spinand->spimem, &op);
 }
 
+static int macronix_set_randomizer(struct spinand_device *spinand, bool enable)
+{
+	return spinand_write_reg_op(spinand, MACRONIX_FEATURE_ADDR_RANDOMIZER,
+				    enable ? MACRONIX_CFG_RANDOMIZER_EN : 0);
+}
+
 static const struct spinand_info macronix_spinand_table[] = {
 	SPINAND_INFO("MX35LF1GE4AB",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x12),
@@ -231,7 +239,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_HAS_QE_BIT,
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout, NULL),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35LF2G24AD",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x24, 0x03),
 		     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 2, 1, 1),
@@ -243,7 +252,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_HAS_PROG_PLANE_SELECT_BIT,
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout, NULL),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35LF2G24AD-Z4I8",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x64, 0x03),
 		     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 1, 1, 1),
@@ -254,7 +264,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_HAS_QE_BIT,
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout, NULL),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35LF4G24AD",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x35, 0x03),
 		     NAND_MEMORG(1, 4096, 256, 64, 2048, 40, 2, 1, 1),
@@ -266,7 +277,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_HAS_PROG_PLANE_SELECT_BIT,
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout, NULL),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35LF4G24AD-Z4I8",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x75, 0x03),
 		     NAND_MEMORG(1, 4096, 256, 64, 2048, 40, 1, 1, 1),
@@ -277,7 +289,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_HAS_QE_BIT,
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout, NULL),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX31LF1GE4BC",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x1e),
 		     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 1),
@@ -327,7 +340,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout,
 				     macronix_ecc_get_status),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35UF4G24AD-Z4I8",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xf5, 0x03),
 		     NAND_MEMORG(1, 4096, 256, 64, 2048, 40, 1, 1, 1),
@@ -340,7 +354,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout,
 				     macronix_ecc_get_status),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35UF4GE4AD",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xb7, 0x03),
 		     NAND_MEMORG(1, 4096, 256, 64, 2048, 40, 1, 1, 1),
@@ -381,7 +396,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout,
 				     macronix_ecc_get_status),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35UF2G24AD-Z4I8",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xe4, 0x03),
 		     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 1, 1, 1),
@@ -394,7 +410,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout,
 				     macronix_ecc_get_status),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35UF2GE4AD",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xa6, 0x03),
 		     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 1, 1, 1),
@@ -444,7 +461,8 @@ static const struct spinand_info macronix_spinand_table[] = {
 		     SPINAND_ECCINFO(&mx35lfxge4ab_ooblayout,
 				     macronix_ecc_get_status),
 		     SPINAND_READ_RETRY(MACRONIX_NUM_READ_RETRY_MODES,
-					macronix_set_read_retry)),
+					macronix_set_read_retry),
+		     SPINAND_RANDOMIZER(macronix_set_randomizer)),
 	SPINAND_INFO("MX35UF1GE4AD",
 		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x96, 0x03),
 		     NAND_MEMORG(1, 2048, 128, 64, 1024, 20, 1, 1, 1),
-- 
2.25.1


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Re: [PATCH v9 2/3] mtd: spi-nand: Add support for randomizer

[Miquel Raynal]

Hi Cheng Ming,

> +static int spinand_randomizer_init(struct spinand_device *spinand)
> +{
> +	struct device_node *np = spinand->spimem->spi->dev.of_node;
> +	u32 rand_val;
> +	int ret;
> +
> +	if (!spinand->set_randomizer)
> +		return 0;
> +
> +	ret = of_property_read_u32(np, "nand-randomizer", &rand_val);
> +	if (ret)
> +		return 0;
> +
> +	return spinand->set_randomizer(spinand, rand_val == 1);

You do not need the "== 1" part. rand_val is cast into a boolean, so any
non zero value will be taken understood as an "enable" and zero will be
treated as "disable", which is fine.

The rest looks fine.

Thanks,
Miquèl

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Re: [PATCH v9 2/3] mtd: spi-nand: Add support for randomizer

[Cheng Ming Lin]

Hi Miquel,

Miquel Raynal <miquel.raynal@bootlin.com> 於 2026年4月22日週三 下午4:08寫道：
>
> Hi Cheng Ming,
>
> > +static int spinand_randomizer_init(struct spinand_device *spinand)
> > +{
> > +     struct device_node *np = spinand->spimem->spi->dev.of_node;
> > +     u32 rand_val;
> > +     int ret;
> > +
> > +     if (!spinand->set_randomizer)
> > +             return 0;
> > +
> > +     ret = of_property_read_u32(np, "nand-randomizer", &rand_val);
> > +     if (ret)
> > +             return 0;
> > +
> > +     return spinand->set_randomizer(spinand, rand_val == 1);
>
> You do not need the "== 1" part. rand_val is cast into a boolean, so any
> non zero value will be taken understood as an "enable" and zero will be
> treated as "disable", which is fine.

Got it, thanks for the tip. I will drop the "== 1" part and rely on the
implicit boolean cast in the next version.

Since the rest of the patch looks fine to you, I will wait for the Device
Tree maintainers' feedback on the dt-binding patch (Patch 1/3) before
spinning v10 to avoid spamming the list.

>
> The rest looks fine.
>
> Thanks,
> Miquèl

Thanks,
Cheng Ming Lin

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