mtd: spinand: add OTP support

The code was ported from linux-6.15

based on a linux commit c06b1f753bea (mtd: spinand: add OTP support)
created by Martin Kurbanov <[email protected]>

Signed-off-by: Mikhail Kshevetskiy <[email protected]>
Reviewed-by: Frieder Schrempf <[email protected]>
Signed-off-by: Michael Trimarchi <[email protected]>

3 files changed, 404 insertions, 10 deletions

diff --git a/drivers/mtd/nand/spi/Makefile b/drivers/mtd/nand/spi/Makefile
index d438747cf37..831760da1c9 100644
--- a/drivers/mtd/nand/spi/Makefile
+++ b/drivers/mtd/nand/spi/Makefile
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 
-spinand-objs := core.o alliancememory.o ato.o esmt.o foresee.o gigadevice.o macronix.o
+spinand-objs := core.o otp.o
+spinand-objs += alliancememory.o ato.o esmt.o foresee.o gigadevice.o macronix.o
 spinand-objs += micron.o paragon.o toshiba.o winbond.o xtx.o
 obj-$(CONFIG_MTD_SPI_NAND) += spinand.o
diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
index 33d0c27f788..f16d3b0335f 100644
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -56,7 +56,7 @@ static int spinand_read_reg_op(struct spinand_device *spinand, u8 reg, u8 *val)
 	return 0;
 }
 
-static int spinand_write_reg_op(struct spinand_device *spinand, u8 reg, u8 val)
+int spinand_write_reg_op(struct spinand_device *spinand, u8 reg, u8 val)
 {
 	struct spi_mem_op op = SPINAND_SET_FEATURE_OP(reg,
 						      spinand->scratchbuf);
@@ -543,10 +543,10 @@ static int spinand_erase_op(struct spinand_device *spinand,
  *
  * Return: 0 on success, a negative error code otherwise.
  */
-static int spinand_wait(struct spinand_device *spinand,
-			unsigned long initial_delay_us,
-			unsigned long poll_delay_us,
-			u8 *s)
+int spinand_wait(struct spinand_device *spinand,
+		 unsigned long initial_delay_us,
+		 unsigned long poll_delay_us,
+		 u8 *s)
 {
 	unsigned long start, stop;
 	u8 status;
@@ -617,8 +617,16 @@ static int spinand_lock_block(struct spinand_device *spinand, u8 lock)
 	return spinand_write_reg_op(spinand, REG_BLOCK_LOCK, lock);
 }
 
-static int spinand_read_page(struct spinand_device *spinand,
-			     const struct nand_page_io_req *req)
+/**
+ * spinand_read_page() - Read a page
+ * @spinand: the spinand device
+ * @req: the I/O request
+ *
+ * Return: 0 or a positive number of bitflips corrected on success.
+ * A negative error code otherwise.
+ */
+int spinand_read_page(struct spinand_device *spinand,
+		      const struct nand_page_io_req *req)
 {
 	struct nand_device *nand = spinand_to_nand(spinand);
 	u8 status;
@@ -648,8 +656,16 @@ static int spinand_read_page(struct spinand_device *spinand,
 	return spinand_ondie_ecc_finish_io_req(nand, (struct nand_page_io_req *)req);
 }
 
-static int spinand_write_page(struct spinand_device *spinand,
-			      const struct nand_page_io_req *req)
+/**
+ * spinand_write_page() - Write a page
+ * @spinand: the spinand device
+ * @req: the I/O request
+ *
+ * Return: 0 or a positive number of bitflips corrected on success.
+ * A negative error code otherwise.
+ */
+int spinand_write_page(struct spinand_device *spinand,
+		       const struct nand_page_io_req *req)
 {
 	struct nand_device *nand = spinand_to_nand(spinand);
 	u8 status;
@@ -1338,6 +1354,8 @@ int spinand_match_and_init(struct spinand_device *spinand,
 		spinand->id.len = 1 + table[i].devid.len;
 		spinand->select_target = table[i].select_target;
 		spinand->set_cont_read = table[i].set_cont_read;
+		spinand->fact_otp = &table[i].fact_otp;
+		spinand->user_otp = &table[i].user_otp;
 		spinand->read_retries = table[i].read_retries;
 		spinand->set_read_retry = table[i].set_read_retry;
 
@@ -1504,6 +1522,12 @@ static int spinand_init(struct spinand_device *spinand)
 	mtd->_block_isreserved = spinand_mtd_block_isreserved;
 	mtd->_erase = spinand_mtd_erase;
 
+	if (spinand_user_otp_size(spinand) || spinand_fact_otp_size(spinand)) {
+		ret = spinand_set_mtd_otp_ops(spinand);
+		if (ret)
+			goto err_cleanup_ecc_engine;
+	}
+
 	ret = mtd_ooblayout_count_freebytes(mtd);
 	if (ret < 0)
 		goto err_cleanup_ecc_engine;
diff --git a/drivers/mtd/nand/spi/otp.c b/drivers/mtd/nand/spi/otp.c
new file mode 100644
index 00000000000..e6ef78d9464
--- /dev/null
+++ b/drivers/mtd/nand/spi/otp.c
@@ -0,0 +1,369 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2025, SaluteDevices. All Rights Reserved.
+ *
+ * Author: Martin Kurbanov <[email protected]>
+ */
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/spinand.h>
+#ifdef __UBOOT__
+#include <spi.h>
+#include <dm/device_compat.h>
+#endif
+
+/**
+ * spinand_otp_page_size() - Get SPI-NAND OTP page size
+ * @spinand: the spinand device
+ *
+ * Return: the OTP page size.
+ */
+size_t spinand_otp_page_size(struct spinand_device *spinand)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+
+	return nanddev_page_size(nand) + nanddev_per_page_oobsize(nand);
+}
+
+static size_t spinand_otp_size(struct spinand_device *spinand,
+			       const struct spinand_otp_layout *layout)
+{
+	return layout->npages * spinand_otp_page_size(spinand);
+}
+
+/**
+ * spinand_fact_otp_size() - Get SPI-NAND factory OTP area size
+ * @spinand: the spinand device
+ *
+ * Return: the OTP size.
+ */
+size_t spinand_fact_otp_size(struct spinand_device *spinand)
+{
+	return spinand_otp_size(spinand, &spinand->fact_otp->layout);
+}
+
+/**
+ * spinand_user_otp_size() - Get SPI-NAND user OTP area size
+ * @spinand: the spinand device
+ *
+ * Return: the OTP size.
+ */
+size_t spinand_user_otp_size(struct spinand_device *spinand)
+{
+	return spinand_otp_size(spinand, &spinand->user_otp->layout);
+}
+
+static int spinand_otp_check_bounds(struct spinand_device *spinand, loff_t ofs,
+				    size_t len,
+				    const struct spinand_otp_layout *layout)
+{
+	if (ofs < 0 || ofs + len > spinand_otp_size(spinand, layout))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int spinand_user_otp_check_bounds(struct spinand_device *spinand,
+					 loff_t ofs, size_t len)
+{
+	return spinand_otp_check_bounds(spinand, ofs, len,
+					&spinand->user_otp->layout);
+}
+
+static int spinand_otp_rw(struct spinand_device *spinand, loff_t ofs,
+			  size_t len, size_t *retlen, u8 *buf, bool is_write,
+			  const struct spinand_otp_layout *layout)
+{
+	struct nand_page_io_req req = {};
+	unsigned long long page;
+	size_t copied = 0;
+	size_t otp_pagesize = spinand_otp_page_size(spinand);
+	int ret;
+
+	if (!len)
+		return 0;
+
+	ret = spinand_otp_check_bounds(spinand, ofs, len, layout);
+	if (ret)
+		return ret;
+
+	ret = spinand_upd_cfg(spinand, CFG_OTP_ENABLE, CFG_OTP_ENABLE);
+	if (ret)
+		return ret;
+
+	page = ofs;
+	req.dataoffs = do_div(page, otp_pagesize);
+	req.pos.page = page + layout->start_page;
+	req.type = is_write ? NAND_PAGE_WRITE : NAND_PAGE_READ;
+	req.mode = MTD_OPS_RAW;
+	req.databuf.in = buf;
+
+	while (copied < len) {
+		req.datalen = min_t(unsigned int,
+				    otp_pagesize - req.dataoffs,
+				    len - copied);
+
+		if (is_write)
+			ret = spinand_write_page(spinand, &req);
+		else
+			ret = spinand_read_page(spinand, &req);
+
+		if (ret < 0)
+			break;
+
+		req.databuf.in += req.datalen;
+		req.pos.page++;
+		req.dataoffs = 0;
+		copied += req.datalen;
+	}
+
+	*retlen = copied;
+
+	if (spinand_upd_cfg(spinand, CFG_OTP_ENABLE, 0)) {
+		dev_warn(spinand->slave->dev,
+			 "Can not disable OTP mode\n");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+/**
+ * spinand_fact_otp_read() - Read from OTP area
+ * @spinand: the spinand device
+ * @ofs: the offset to read
+ * @len: the number of data bytes to read
+ * @retlen: the pointer to variable to store the number of read bytes
+ * @buf: the buffer to store the read data
+ *
+ * Return: 0 on success, an error code otherwise.
+ */
+int spinand_fact_otp_read(struct spinand_device *spinand, loff_t ofs,
+			  size_t len, size_t *retlen, u8 *buf)
+{
+	return spinand_otp_rw(spinand, ofs, len, retlen, buf, false,
+			      &spinand->fact_otp->layout);
+}
+
+/**
+ * spinand_user_otp_read() - Read from OTP area
+ * @spinand: the spinand device
+ * @ofs: the offset to read
+ * @len: the number of data bytes to read
+ * @retlen: the pointer to variable to store the number of read bytes
+ * @buf: the buffer to store the read data
+ *
+ * Return: 0 on success, an error code otherwise.
+ */
+int spinand_user_otp_read(struct spinand_device *spinand, loff_t ofs,
+			  size_t len, size_t *retlen, u8 *buf)
+{
+	return spinand_otp_rw(spinand, ofs, len, retlen, buf, false,
+			      &spinand->user_otp->layout);
+}
+
+/**
+ * spinand_user_otp_write() - Write to OTP area
+ * @spinand:  the spinand device
+ * @ofs: the offset to write to
+ * @len: the number of bytes to write
+ * @retlen: the pointer to variable to store the number of written bytes
+ * @buf: the buffer with data to write
+ *
+ * Return: 0 on success, an error code otherwise.
+ */
+int spinand_user_otp_write(struct spinand_device *spinand, loff_t ofs,
+			   size_t len, size_t *retlen, const u8 *buf)
+{
+	return spinand_otp_rw(spinand, ofs, len, retlen, (u8 *)buf, true,
+			      &spinand->user_otp->layout);
+}
+
+static int spinand_mtd_otp_info(struct mtd_info *mtd, size_t len,
+				size_t *retlen, struct otp_info *buf,
+				bool is_fact)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	int ret;
+
+	*retlen = 0;
+
+	mutex_lock(&spinand->lock);
+
+	if (is_fact)
+		ret = spinand->fact_otp->ops->info(spinand, len, buf, retlen);
+	else
+		ret = spinand->user_otp->ops->info(spinand, len, buf, retlen);
+
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+static int spinand_mtd_fact_otp_info(struct mtd_info *mtd, size_t len,
+				     size_t *retlen, struct otp_info *buf)
+{
+	return spinand_mtd_otp_info(mtd, len, retlen, buf, true);
+}
+
+static int spinand_mtd_user_otp_info(struct mtd_info *mtd, size_t len,
+				     size_t *retlen, struct otp_info *buf)
+{
+	return spinand_mtd_otp_info(mtd, len, retlen, buf, false);
+}
+
+static int spinand_mtd_otp_read(struct mtd_info *mtd, loff_t ofs, size_t len,
+				size_t *retlen, u8 *buf, bool is_fact)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	int ret;
+
+	*retlen = 0;
+
+	if (!len)
+		return 0;
+
+	ret = spinand_otp_check_bounds(spinand, ofs, len,
+				       is_fact ? &spinand->fact_otp->layout :
+						 &spinand->user_otp->layout);
+	if (ret)
+		return ret;
+
+	mutex_lock(&spinand->lock);
+
+	if (is_fact)
+		ret = spinand->fact_otp->ops->read(spinand, ofs, len, retlen,
+						   buf);
+	else
+		ret = spinand->user_otp->ops->read(spinand, ofs, len, retlen,
+						   buf);
+
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+static int spinand_mtd_fact_otp_read(struct mtd_info *mtd, loff_t ofs,
+				     size_t len, size_t *retlen, u8 *buf)
+{
+	return spinand_mtd_otp_read(mtd, ofs, len, retlen, buf, true);
+}
+
+static int spinand_mtd_user_otp_read(struct mtd_info *mtd, loff_t ofs,
+				     size_t len, size_t *retlen, u8 *buf)
+{
+	return spinand_mtd_otp_read(mtd, ofs, len, retlen, buf, false);
+}
+
+static int spinand_mtd_user_otp_write(struct mtd_info *mtd, loff_t ofs,
+				      size_t len, size_t *retlen, u_char *buf)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	const struct spinand_user_otp_ops *ops = spinand->user_otp->ops;
+	int ret;
+
+	*retlen = 0;
+
+	if (!len)
+		return 0;
+
+	ret = spinand_user_otp_check_bounds(spinand, ofs, len);
+	if (ret)
+		return ret;
+
+	mutex_lock(&spinand->lock);
+	ret = ops->write(spinand, ofs, len, retlen, buf);
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+#ifndef __UBOOT__
+static int spinand_mtd_user_otp_erase(struct mtd_info *mtd, loff_t ofs,
+				      size_t len)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	const struct spinand_user_otp_ops *ops = spinand->user_otp->ops;
+	int ret;
+
+	if (!len)
+		return 0;
+
+	ret = spinand_user_otp_check_bounds(spinand, ofs, len);
+	if (ret)
+		return ret;
+
+	mutex_lock(&spinand->lock);
+	ret = ops->erase(spinand, ofs, len);
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+#endif
+
+static int spinand_mtd_user_otp_lock(struct mtd_info *mtd, loff_t ofs,
+				     size_t len)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	const struct spinand_user_otp_ops *ops = spinand->user_otp->ops;
+	int ret;
+
+	if (!len)
+		return 0;
+
+	ret = spinand_user_otp_check_bounds(spinand, ofs, len);
+	if (ret)
+		return ret;
+
+	mutex_lock(&spinand->lock);
+	ret = ops->lock(spinand, ofs, len);
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+/**
+ * spinand_set_mtd_otp_ops() - Setup OTP methods
+ * @spinand: the spinand device
+ *
+ * Setup OTP methods.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int spinand_set_mtd_otp_ops(struct spinand_device *spinand)
+{
+	struct mtd_info *mtd = spinand_to_mtd(spinand);
+	const struct spinand_fact_otp_ops *fact_ops = spinand->fact_otp->ops;
+	const struct spinand_user_otp_ops *user_ops = spinand->user_otp->ops;
+
+	if (!user_ops && !fact_ops)
+		return -EINVAL;
+
+	if (user_ops) {
+		if (user_ops->info)
+			mtd->_get_user_prot_info = spinand_mtd_user_otp_info;
+
+		if (user_ops->read)
+			mtd->_read_user_prot_reg = spinand_mtd_user_otp_read;
+
+		if (user_ops->write)
+			mtd->_write_user_prot_reg = spinand_mtd_user_otp_write;
+
+		if (user_ops->lock)
+			mtd->_lock_user_prot_reg = spinand_mtd_user_otp_lock;
+#ifndef __UBOOT__
+		if (user_ops->erase)
+			mtd->_erase_user_prot_reg = spinand_mtd_user_otp_erase;
+#endif
+	}
+
+	if (fact_ops) {
+		if (fact_ops->info)
+			mtd->_get_fact_prot_info = spinand_mtd_fact_otp_info;
+
+		if (fact_ops->read)
+			mtd->_read_fact_prot_reg = spinand_mtd_fact_otp_read;
+	}
+
+	return 0;
+}