mtd: nand: Add core infrastructure to support SPI NANDs

Add a SPI NAND framework based on the generic NAND framework and the
spi-mem infrastructure.

In its current state, this framework supports the following features:

- single/dual/quad IO modes
- on-die ECC
Signed-off-by: Peter Pan <peterpandong@micron.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

drivers/mtd/nand/Kconfig

@@ -4,3 +4,4 @@ config MTD_NAND_CORE
 source "drivers/mtd/nand/onenand/Kconfig"
 
 source "drivers/mtd/nand/raw/Kconfig"
+source "drivers/mtd/nand/spi/Kconfig"

drivers/mtd/nand/Makefile

@@ -5,3 +5,4 @@ obj-$(CONFIG_MTD_NAND_CORE) += nandcore.o
 
 obj-y	+= onenand/
 obj-y	+= raw/
+obj-y	+= spi/

drivers/mtd/nand/spi/Kconfig

+menuconfig MTD_SPI_NAND
+	tristate "SPI NAND device Support"
+	select MTD_NAND_CORE
+	depends on SPI_MASTER
+	select SPI_MEM
+	help
+	  This is the framework for the SPI NAND device drivers.

drivers/mtd/nand/spi/Makefile

+# SPDX-License-Identifier: GPL-2.0
+spinand-objs := core.o
+obj-$(CONFIG_MTD_SPI_NAND) += spinand.o

drivers/mtd/nand/spi/core.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2016-2017 Micron Technology, Inc.
+ *
+ * Authors:
+ *	Peter Pan <peterpandong@micron.com>
+ *	Boris Brezillon <boris.brezillon@bootlin.com>
+ */
+
+#define pr_fmt(fmt)	"spi-nand: " fmt
+
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mtd/spinand.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+
+static void spinand_cache_op_adjust_colum(struct spinand_device *spinand,
+					  const struct nand_page_io_req *req,
+					  u16 *column)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	unsigned int shift;
+
+	if (nand->memorg.planes_per_lun < 2)
+		return;
+
+	/* The plane number is passed in MSB just above the column address */
+	shift = fls(nand->memorg.pagesize);
+	*column |= req->pos.plane << shift;
+}
+
+static int spinand_read_reg_op(struct spinand_device *spinand, u8 reg, u8 *val)
+{
+	struct spi_mem_op op = SPINAND_GET_FEATURE_OP(reg,
+						      spinand->scratchbuf);
+	int ret;
+
+	ret = spi_mem_exec_op(spinand->spimem, &op);
+	if (ret)
+		return ret;
+
+	*val = *spinand->scratchbuf;
+	return 0;
+}
+
+static 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);
+
+	*spinand->scratchbuf = val;
+	return spi_mem_exec_op(spinand->spimem, &op);
+}
+
+static int spinand_read_status(struct spinand_device *spinand, u8 *status)
+{
+	return spinand_read_reg_op(spinand, REG_STATUS, status);
+}
+
+static int spinand_get_cfg(struct spinand_device *spinand, u8 *cfg)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+
+	if (WARN_ON(spinand->cur_target < 0 ||
+		    spinand->cur_target >= nand->memorg.ntargets))
+		return -EINVAL;
+
+	*cfg = spinand->cfg_cache[spinand->cur_target];
+	return 0;
+}
+
+static int spinand_set_cfg(struct spinand_device *spinand, u8 cfg)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	int ret;
+
+	if (WARN_ON(spinand->cur_target < 0 ||
+		    spinand->cur_target >= nand->memorg.ntargets))
+		return -EINVAL;
+
+	if (spinand->cfg_cache[spinand->cur_target] == cfg)
+		return 0;
+
+	ret = spinand_write_reg_op(spinand, REG_CFG, cfg);
+	if (ret)
+		return ret;
+
+	spinand->cfg_cache[spinand->cur_target] = cfg;
+	return 0;
+}
+
+/**
+ * spinand_upd_cfg() - Update the configuration register
+ * @spinand: the spinand device
+ * @mask: the mask encoding the bits to update in the config reg
+ * @val: the new value to apply
+ *
+ * Update the configuration register.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int spinand_upd_cfg(struct spinand_device *spinand, u8 mask, u8 val)
+{
+	int ret;
+	u8 cfg;
+
+	ret = spinand_get_cfg(spinand, &cfg);
+	if (ret)
+		return ret;
+
+	cfg &= ~mask;
+	cfg |= val;
+
+	return spinand_set_cfg(spinand, cfg);
+}
+
+/**
+ * spinand_select_target() - Select a specific NAND target/die
+ * @spinand: the spinand device
+ * @target: the target/die to select
+ *
+ * Select a new target/die. If chip only has one die, this function is a NOOP.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int spinand_select_target(struct spinand_device *spinand, unsigned int target)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	int ret;
+
+	if (WARN_ON(target >= nand->memorg.ntargets))
+		return -EINVAL;
+
+	if (spinand->cur_target == target)
+		return 0;
+
+	if (nand->memorg.ntargets == 1) {
+		spinand->cur_target = target;
+		return 0;
+	}
+
+	ret = spinand->select_target(spinand, target);
+	if (ret)
+		return ret;
+
+	spinand->cur_target = target;
+	return 0;
+}
+
+static int spinand_init_cfg_cache(struct spinand_device *spinand)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	struct device *dev = &spinand->spimem->spi->dev;
+	unsigned int target;
+	int ret;
+
+	spinand->cfg_cache = devm_kcalloc(dev,
+					  nand->memorg.ntargets,
+					  sizeof(*spinand->cfg_cache),
+					  GFP_KERNEL);
+	if (!spinand->cfg_cache)
+		return -ENOMEM;
+
+	for (target = 0; target < nand->memorg.ntargets; target++) {
+		ret = spinand_select_target(spinand, target);
+		if (ret)
+			return ret;
+
+		/*
+		 * We use spinand_read_reg_op() instead of spinand_get_cfg()
+		 * here to bypass the config cache.
+		 */
+		ret = spinand_read_reg_op(spinand, REG_CFG,
+					  &spinand->cfg_cache[target]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int spinand_init_quad_enable(struct spinand_device *spinand)
+{
+	bool enable = false;
+
+	if (!(spinand->flags & SPINAND_HAS_QE_BIT))
+		return 0;
+
+	if (spinand->op_templates.read_cache->data.buswidth == 4 ||
+	    spinand->op_templates.write_cache->data.buswidth == 4 ||
+	    spinand->op_templates.update_cache->data.buswidth == 4)
+		enable = true;
+
+	return spinand_upd_cfg(spinand, CFG_QUAD_ENABLE,
+			       enable ? CFG_QUAD_ENABLE : 0);
+}
+
+static int spinand_ecc_enable(struct spinand_device *spinand,
+			      bool enable)
+{
+	return spinand_upd_cfg(spinand, CFG_ECC_ENABLE,
+			       enable ? CFG_ECC_ENABLE : 0);
+}
+
+static int spinand_write_enable_op(struct spinand_device *spinand)
+{
+	struct spi_mem_op op = SPINAND_WR_EN_DIS_OP(true);
+
+	return spi_mem_exec_op(spinand->spimem, &op);
+}
+
+static int spinand_load_page_op(struct spinand_device *spinand,
+				const struct nand_page_io_req *req)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	unsigned int row = nanddev_pos_to_row(nand, &req->pos);
+	struct spi_mem_op op = SPINAND_PAGE_READ_OP(row);
+
+	return spi_mem_exec_op(spinand->spimem, &op);
+}
+
+static int spinand_read_from_cache_op(struct spinand_device *spinand,
+				      const struct nand_page_io_req *req)
+{
+	struct spi_mem_op op = *spinand->op_templates.read_cache;
+	struct nand_device *nand = spinand_to_nand(spinand);
+	struct mtd_info *mtd = nanddev_to_mtd(nand);
+	struct nand_page_io_req adjreq = *req;
+	unsigned int nbytes = 0;
+	void *buf = NULL;
+	u16 column = 0;
+	int ret;
+
+	if (req->datalen) {
+		adjreq.datalen = nanddev_page_size(nand);
+		adjreq.dataoffs = 0;
+		adjreq.databuf.in = spinand->databuf;
+		buf = spinand->databuf;
+		nbytes = adjreq.datalen;
+	}
+
+	if (req->ooblen) {
+		adjreq.ooblen = nanddev_per_page_oobsize(nand);
+		adjreq.ooboffs = 0;
+		adjreq.oobbuf.in = spinand->oobbuf;
+		nbytes += nanddev_per_page_oobsize(nand);
+		if (!buf) {
+			buf = spinand->oobbuf;
+			column = nanddev_page_size(nand);
+		}
+	}
+
+	spinand_cache_op_adjust_colum(spinand, &adjreq, &column);
+	op.addr.val = column;
+
+	/*
+	 * Some controllers are limited in term of max RX data size. In this
+	 * case, just repeat the READ_CACHE operation after updating the
+	 * column.
+	 */
+	while (nbytes) {
+		op.data.buf.in = buf;
+		op.data.nbytes = nbytes;
+		ret = spi_mem_adjust_op_size(spinand->spimem, &op);
+		if (ret)
+			return ret;
+
+		ret = spi_mem_exec_op(spinand->spimem, &op);
+		if (ret)
+			return ret;
+
+		buf += op.data.nbytes;
+		nbytes -= op.data.nbytes;
+		op.addr.val += op.data.nbytes;
+	}
+
+	if (req->datalen)
+		memcpy(req->databuf.in, spinand->databuf + req->dataoffs,
+		       req->datalen);
+
+	if (req->ooblen) {
+		if (req->mode == MTD_OPS_AUTO_OOB)
+			mtd_ooblayout_get_databytes(mtd, req->oobbuf.in,
+						    spinand->oobbuf,
+						    req->ooboffs,
+						    req->ooblen);
+		else
+			memcpy(req->oobbuf.in, spinand->oobbuf + req->ooboffs,
+			       req->ooblen);
+	}
+
+	return 0;
+}
+
+static int spinand_write_to_cache_op(struct spinand_device *spinand,
+				     const struct nand_page_io_req *req)
+{
+	struct spi_mem_op op = *spinand->op_templates.write_cache;
+	struct nand_device *nand = spinand_to_nand(spinand);
+	struct mtd_info *mtd = nanddev_to_mtd(nand);
+	struct nand_page_io_req adjreq = *req;
+	unsigned int nbytes = 0;
+	void *buf = NULL;
+	u16 column = 0;
+	int ret;
+
+	memset(spinand->databuf, 0xff,
+	       nanddev_page_size(nand) +
+	       nanddev_per_page_oobsize(nand));
+
+	if (req->datalen) {
+		memcpy(spinand->databuf + req->dataoffs, req->databuf.out,
+		       req->datalen);
+		adjreq.dataoffs = 0;
+		adjreq.datalen = nanddev_page_size(nand);
+		adjreq.databuf.out = spinand->databuf;
+		nbytes = adjreq.datalen;
+		buf = spinand->databuf;
+	}
+
+	if (req->ooblen) {
+		if (req->mode == MTD_OPS_AUTO_OOB)
+			mtd_ooblayout_set_databytes(mtd, req->oobbuf.out,
+						    spinand->oobbuf,
+						    req->ooboffs,
+						    req->ooblen);
+		else
+			memcpy(spinand->oobbuf + req->ooboffs, req->oobbuf.out,
+			       req->ooblen);
+
+		adjreq.ooblen = nanddev_per_page_oobsize(nand);
+		adjreq.ooboffs = 0;
+		nbytes += nanddev_per_page_oobsize(nand);
+		if (!buf) {
+			buf = spinand->oobbuf;
+			column = nanddev_page_size(nand);
+		}
+	}
+
+	spinand_cache_op_adjust_colum(spinand, &adjreq, &column);
+
+	op = *spinand->op_templates.write_cache;
+	op.addr.val = column;
+
+	/*
+	 * Some controllers are limited in term of max TX data size. In this
+	 * case, split the operation into one LOAD CACHE and one or more
+	 * LOAD RANDOM CACHE.
+	 */
+	while (nbytes) {
+		op.data.buf.out = buf;
+		op.data.nbytes = nbytes;
+
+		ret = spi_mem_adjust_op_size(spinand->spimem, &op);
+		if (ret)
+			return ret;
+
+		ret = spi_mem_exec_op(spinand->spimem, &op);
+		if (ret)
+			return ret;
+
+		buf += op.data.nbytes;
+		nbytes -= op.data.nbytes;
+		op.addr.val += op.data.nbytes;
+
+		/*
+		 * We need to use the RANDOM LOAD CACHE operation if there's
+		 * more than one iteration, because the LOAD operation resets
+		 * the cache to 0xff.
+		 */
+		if (nbytes) {
+			column = op.addr.val;
+			op = *spinand->op_templates.update_cache;
+			op.addr.val = column;
+		}
+	}
+
+	return 0;
+}
+
+static int spinand_program_op(struct spinand_device *spinand,
+			      const struct nand_page_io_req *req)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	unsigned int row = nanddev_pos_to_row(nand, &req->pos);
+	struct spi_mem_op op = SPINAND_PROG_EXEC_OP(row);
+
+	return spi_mem_exec_op(spinand->spimem, &op);
+}
+
+static int spinand_erase_op(struct spinand_device *spinand,
+			    const struct nand_pos *pos)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	unsigned int row = nanddev_pos_to_row(nand, pos);
+	struct spi_mem_op op = SPINAND_BLK_ERASE_OP(row);
+
+	return spi_mem_exec_op(spinand->spimem, &op);
+}
+
+static int spinand_wait(struct spinand_device *spinand, u8 *s)
+{
+	unsigned long timeo =  jiffies + msecs_to_jiffies(400);
+	u8 status;
+	int ret;
+
+	do {
+		ret = spinand_read_status(spinand, &status);
+		if (ret)
+			return ret;
+
+		if (!(status & STATUS_BUSY))
+			goto out;
+	} while (time_before(jiffies, timeo));
+
+	/*
+	 * Extra read, just in case the STATUS_READY bit has changed
+	 * since our last check
+	 */
+	ret = spinand_read_status(spinand, &status);
+	if (ret)
+		return ret;
+
+out:
+	if (s)
+		*s = status;
+
+	return status & STATUS_BUSY ? -ETIMEDOUT : 0;
+}
+
+static int spinand_read_id_op(struct spinand_device *spinand, u8 *buf)
+{
+	struct spi_mem_op op = SPINAND_READID_OP(0, spinand->scratchbuf,
+						 SPINAND_MAX_ID_LEN);
+	int ret;
+
+	ret = spi_mem_exec_op(spinand->spimem, &op);
+	if (!ret)
+		memcpy(buf, spinand->scratchbuf, SPINAND_MAX_ID_LEN);
+
+	return ret;
+}
+
+static int spinand_reset_op(struct spinand_device *spinand)
+{
+	struct spi_mem_op op = SPINAND_RESET_OP;
+	int ret;
+
+	ret = spi_mem_exec_op(spinand->spimem, &op);
+	if (ret)
+		return ret;
+
+	return spinand_wait(spinand, NULL);
+}
+
+static int spinand_lock_block(struct spinand_device *spinand, u8 lock)
+{
+	return spinand_write_reg_op(spinand, REG_BLOCK_LOCK, lock);
+}
+
+static int spinand_check_ecc_status(struct spinand_device *spinand, u8 status)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+
+	if (spinand->eccinfo.get_status)
+		return spinand->eccinfo.get_status(spinand, status);
+
+	switch (status & STATUS_ECC_MASK) {
+	case STATUS_ECC_NO_BITFLIPS:
+		return 0;
+
+	case STATUS_ECC_HAS_BITFLIPS:
+		/*
+		 * We have no way to know exactly how many bitflips have been
+		 * fixed, so let's return the maximum possible value so that
+		 * wear-leveling layers move the data immediately.
+		 */
+		return nand->eccreq.strength;
+
+	case STATUS_ECC_UNCOR_ERROR:
+		return -EBADMSG;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int spinand_read_page(struct spinand_device *spinand,
+			     const struct nand_page_io_req *req,
+			     bool ecc_enabled)
+{
+	u8 status;
+	int ret;
+
+	ret = spinand_load_page_op(spinand, req);
+	if (ret)
+		return ret;
+
+	ret = spinand_wait(spinand, &status);
+	if (ret < 0)
+		return ret;
+
+	ret = spinand_read_from_cache_op(spinand, req);
+	if (ret)
+		return ret;
+
+	if (!ecc_enabled)
+		return 0;
+
+	return spinand_check_ecc_status(spinand, status);
+}
+
+static int spinand_write_page(struct spinand_device *spinand,
+			      const struct nand_page_io_req *req)
+{
+	u8 status;
+	int ret;
+
+	ret = spinand_write_enable_op(spinand);
+	if (ret)
+		return ret;
+
+	ret = spinand_write_to_cache_op(spinand, req);
+	if (ret)
+		return ret;
+
+	ret = spinand_program_op(spinand, req);
+	if (ret)
+		return ret;
+
+	ret = spinand_wait(spinand, &status);
+	if (!ret && (status & STATUS_PROG_FAILED))
+		ret = -EIO;
+
+	return ret;
+}
+
+static int spinand_mtd_read(struct mtd_info *mtd, loff_t from,
+			    struct mtd_oob_ops *ops)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	struct nand_device *nand = mtd_to_nanddev(mtd);
+	unsigned int max_bitflips = 0;
+	struct nand_io_iter iter;
+	bool enable_ecc = false;
+	bool ecc_failed = false;
+	int ret = 0;
+
+	if (ops->mode != MTD_OPS_RAW && spinand->eccinfo.ooblayout)
+		enable_ecc = true;
+
+	mutex_lock(&spinand->lock);
+
+	nanddev_io_for_each_page(nand, from, ops, &iter) {
+		ret = spinand_select_target(spinand, iter.req.pos.target);
+		if (ret)
+			break;
+
+		ret = spinand_ecc_enable(spinand, enable_ecc);
+		if (ret)
+			break;
+
+		ret = spinand_read_page(spinand, &iter.req, enable_ecc);
+		if (ret < 0 && ret != -EBADMSG)
+			break;
+
+		if (ret == -EBADMSG) {
+			ecc_failed = true;
+			mtd->ecc_stats.failed++;
+			ret = 0;
+		} else {
+			mtd->ecc_stats.corrected += ret;
+			max_bitflips = max_t(unsigned int, max_bitflips, ret);
+		}
+
+		ops->retlen += iter.req.datalen;
+		ops->oobretlen += iter.req.ooblen;
+	}
+
+	mutex_unlock(&spinand->lock);
+
+	if (ecc_failed && !ret)
+		ret = -EBADMSG;
+
+	return ret ? ret : max_bitflips;
+}
+
+static int spinand_mtd_write(struct mtd_info *mtd, loff_t to,
+			     struct mtd_oob_ops *ops)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	struct nand_device *nand = mtd_to_nanddev(mtd);
+	struct nand_io_iter iter;
+	bool enable_ecc = false;
+	int ret = 0;
+
+	if (ops->mode != MTD_OPS_RAW && mtd->ooblayout)
+		enable_ecc = true;
+
+	mutex_lock(&spinand->lock);
+
+	nanddev_io_for_each_page(nand, to, ops, &iter) {
+		ret = spinand_select_target(spinand, iter.req.pos.target);
+		if (ret)
+			break;
+
+		ret = spinand_ecc_enable(spinand, enable_ecc);
+		if (ret)
+			break;
+
+		ret = spinand_write_page(spinand, &iter.req);
+		if (ret)
+			break;
+
+		ops->retlen += iter.req.datalen;
+		ops->oobretlen += iter.req.ooblen;
+	}
+
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+static bool spinand_isbad(struct nand_device *nand, const struct nand_pos *pos)
+{
+	struct spinand_device *spinand = nand_to_spinand(nand);
+	struct nand_page_io_req req = {
+		.pos = *pos,
+		.ooblen = 2,
+		.ooboffs = 0,
+		.oobbuf.in = spinand->oobbuf,
+		.mode = MTD_OPS_RAW,
+	};
+
+	memset(spinand->oobbuf, 0, 2);
+	spinand_select_target(spinand, pos->target);
+	spinand_read_page(spinand, &req, false);
+	if (spinand->oobbuf[0] != 0xff || spinand->oobbuf[1] != 0xff)
+		return true;
+
+	return false;
+}
+
+static int spinand_mtd_block_isbad(struct mtd_info *mtd, loff_t offs)
+{
+	struct nand_device *nand = mtd_to_nanddev(mtd);
+	struct spinand_device *spinand = nand_to_spinand(nand);
+	struct nand_pos pos;
+	int ret;
+
+	nanddev_offs_to_pos(nand, offs, &pos);
+	mutex_lock(&spinand->lock);
+	ret = nanddev_isbad(nand, &pos);
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+static int spinand_markbad(struct nand_device *nand, const struct nand_pos *pos)
+{
+	struct spinand_device *spinand = nand_to_spinand(nand);
+	struct nand_page_io_req req = {
+		.pos = *pos,
+		.ooboffs = 0,
+		.ooblen = 2,
+		.oobbuf.out = spinand->oobbuf,
+	};
+	int ret;
+
+	/* Erase block before marking it bad. */
+	ret = spinand_select_target(spinand, pos->target);
+	if (ret)
+		return ret;
+
+	ret = spinand_write_enable_op(spinand);
+	if (ret)
+		return ret;
+
+	spinand_erase_op(spinand, pos);
+
+	memset(spinand->oobbuf, 0, 2);
+	return spinand_write_page(spinand, &req);
+}
+
+static int spinand_mtd_block_markbad(struct mtd_info *mtd, loff_t offs)
+{
+	struct nand_device *nand = mtd_to_nanddev(mtd);
+	struct spinand_device *spinand = nand_to_spinand(nand);
+	struct nand_pos pos;
+	int ret;
+
+	nanddev_offs_to_pos(nand, offs, &pos);
+	mutex_lock(&spinand->lock);
+	ret = nanddev_markbad(nand, &pos);
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+static int spinand_erase(struct nand_device *nand, const struct nand_pos *pos)
+{
+	struct spinand_device *spinand = nand_to_spinand(nand);
+	u8 status;
+	int ret;
+
+	ret = spinand_select_target(spinand, pos->target);
+	if (ret)
+		return ret;
+
+	ret = spinand_write_enable_op(spinand);
+	if (ret)
+		return ret;
+
+	ret = spinand_erase_op(spinand, pos);
+	if (ret)
+		return ret;
+
+	ret = spinand_wait(spinand, &status);
+	if (!ret && (status & STATUS_ERASE_FAILED))
+		ret = -EIO;
+
+	return ret;
+}
+
+static int spinand_mtd_erase(struct mtd_info *mtd,
+			     struct erase_info *einfo)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	int ret;
+
+	mutex_lock(&spinand->lock);
+	ret = nanddev_mtd_erase(mtd, einfo);
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+static int spinand_mtd_block_isreserved(struct mtd_info *mtd, loff_t offs)
+{
+	struct spinand_device *spinand = mtd_to_spinand(mtd);
+	struct nand_device *nand = mtd_to_nanddev(mtd);
+	struct nand_pos pos;
+	int ret;
+
+	nanddev_offs_to_pos(nand, offs, &pos);
+	mutex_lock(&spinand->lock);
+	ret = nanddev_isreserved(nand, &pos);
+	mutex_unlock(&spinand->lock);
+
+	return ret;
+}
+
+static const struct nand_ops spinand_ops = {
+	.erase = spinand_erase,
+	.markbad = spinand_markbad,
+	.isbad = spinand_isbad,
+};
+
+static int spinand_manufacturer_detect(struct spinand_device *spinand)
+{
+	return -ENOTSUPP;
+}
+
+static int spinand_manufacturer_init(struct spinand_device *spinand)
+{
+	if (spinand->manufacturer->ops->init)
+		return spinand->manufacturer->ops->init(spinand);
+
+	return 0;
+}
+
+static void spinand_manufacturer_cleanup(struct spinand_device *spinand)
+{
+	/* Release manufacturer private data */
+	if (spinand->manufacturer->ops->cleanup)
+		return spinand->manufacturer->ops->cleanup(spinand);
+}
+
+static const struct spi_mem_op *
+spinand_select_op_variant(struct spinand_device *spinand,
+			  const struct spinand_op_variants *variants)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	unsigned int i;
+
+	for (i = 0; i < variants->nops; i++) {
+		struct spi_mem_op op = variants->ops[i];
+		unsigned int nbytes;
+		int ret;
+
+		nbytes = nanddev_per_page_oobsize(nand) +
+			 nanddev_page_size(nand);
+
+		while (nbytes) {
+			op.data.nbytes = nbytes;
+			ret = spi_mem_adjust_op_size(spinand->spimem, &op);
+			if (ret)
+				break;
+
+			if (!spi_mem_supports_op(spinand->spimem, &op))
+				break;
+
+			nbytes -= op.data.nbytes;
+		}
+
+		if (!nbytes)
+			return &variants->ops[i];
+	}
+
+	return NULL;
+}
+
+/**
+ * spinand_match_and_init() - Try to find a match between a device ID and an
+ *			      entry in a spinand_info table
+ * @spinand: SPI NAND object
+ * @table: SPI NAND device description table
+ * @table_size: size of the device description table
+ *
+ * Should be used by SPI NAND manufacturer drivers when they want to find a
+ * match between a device ID retrieved through the READ_ID command and an
+ * entry in the SPI NAND description table. If a match is found, the spinand
+ * object will be initialized with information provided by the matching
+ * spinand_info entry.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int spinand_match_and_init(struct spinand_device *spinand,
+			   const struct spinand_info *table,
+			   unsigned int table_size, u8 devid)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+	unsigned int i;
+
+	for (i = 0; i < table_size; i++) {
+		const struct spinand_info *info = &table[i];
+		const struct spi_mem_op *op;
+
+		if (devid != info->devid)
+			continue;
+
+		nand->memorg = table[i].memorg;
+		nand->eccreq = table[i].eccreq;
+		spinand->eccinfo = table[i].eccinfo;
+		spinand->flags = table[i].flags;
+		spinand->select_target = table[i].select_target;
+
+		op = spinand_select_op_variant(spinand,
+					       info->op_variants.read_cache);
+		if (!op)
+			return -ENOTSUPP;
+
+		spinand->op_templates.read_cache = op;
+
+		op = spinand_select_op_variant(spinand,
+					       info->op_variants.write_cache);
+		if (!op)
+			return -ENOTSUPP;
+
+		spinand->op_templates.write_cache = op;
+
+		op = spinand_select_op_variant(spinand,
+					       info->op_variants.update_cache);
+		spinand->op_templates.update_cache = op;
+
+		return 0;
+	}
+
+	return -ENOTSUPP;
+}
+
+static int spinand_detect(struct spinand_device *spinand)
+{
+	struct device *dev = &spinand->spimem->spi->dev;
+	struct nand_device *nand = spinand_to_nand(spinand);
+	int ret;
+
+	ret = spinand_reset_op(spinand);
+	if (ret)
+		return ret;
+
+	ret = spinand_read_id_op(spinand, spinand->id.data);
+	if (ret)
+		return ret;
+
+	spinand->id.len = SPINAND_MAX_ID_LEN;
+
+	ret = spinand_manufacturer_detect(spinand);
+	if (ret) {
+		dev_err(dev, "unknown raw ID %*phN\n", SPINAND_MAX_ID_LEN,
+			spinand->id.data);
+		return ret;
+	}
+
+	if (nand->memorg.ntargets > 1 && !spinand->select_target) {
+		dev_err(dev,
+			"SPI NANDs with more than one die must implement ->select_target()\n");
+		return -EINVAL;
+	}
+
+	dev_info(&spinand->spimem->spi->dev,
+		 "%s SPI NAND was found.\n", spinand->manufacturer->name);
+	dev_info(&spinand->spimem->spi->dev,
+		 "%llu MiB, block size: %zu KiB, page size: %zu, OOB size: %u\n",
+		 nanddev_size(nand) >> 20, nanddev_eraseblock_size(nand) >> 10,
+		 nanddev_page_size(nand), nanddev_per_page_oobsize(nand));
+
+	return 0;
+}
+
+static int spinand_noecc_ooblayout_ecc(struct mtd_info *mtd, int section,
+				       struct mtd_oob_region *region)
+{
+	return -ERANGE;
+}
+
+static int spinand_noecc_ooblayout_free(struct mtd_info *mtd, int section,
+					struct mtd_oob_region *region)
+{
+	if (section)
+		return -ERANGE;
+
+	/* Reserve 2 bytes for the BBM. */
+	region->offset = 2;
+	region->length = 62;
+
+	return 0;
+}
+
+static const struct mtd_ooblayout_ops spinand_noecc_ooblayout = {
+	.ecc = spinand_noecc_ooblayout_ecc,
+	.free = spinand_noecc_ooblayout_free,
+};
+
+static int spinand_init(struct spinand_device *spinand)
+{
+	struct device *dev = &spinand->spimem->spi->dev;
+	struct mtd_info *mtd = spinand_to_mtd(spinand);
+	struct nand_device *nand = mtd_to_nanddev(mtd);
+	int ret, i;
+
+	/*
+	 * We need a scratch buffer because the spi_mem interface requires that
+	 * buf passed in spi_mem_op->data.buf be DMA-able.
+	 */
+	spinand->scratchbuf = kzalloc(SPINAND_MAX_ID_LEN, GFP_KERNEL);
+	if (!spinand->scratchbuf)
+		return -ENOMEM;
+
+	ret = spinand_detect(spinand);
+	if (ret)
+		goto err_free_bufs;
+
+	/*
+	 * Use kzalloc() instead of devm_kzalloc() here, because some drivers
+	 * may use this buffer for DMA access.
+	 * Memory allocated by devm_ does not guarantee DMA-safe alignment.
+	 */
+	spinand->databuf = kzalloc(nanddev_page_size(nand) +
+			       nanddev_per_page_oobsize(nand),
+			       GFP_KERNEL);
+	if (!spinand->databuf) {
+		ret = -ENOMEM;
+		goto err_free_bufs;
+	}
+
+	spinand->oobbuf = spinand->databuf + nanddev_page_size(nand);
+
+	ret = spinand_init_cfg_cache(spinand);
+	if (ret)
+		goto err_free_bufs;
+
+	ret = spinand_init_quad_enable(spinand);
+	if (ret)
+		goto err_free_bufs;
+
+	ret = spinand_upd_cfg(spinand, CFG_OTP_ENABLE, 0);
+	if (ret)
+		goto err_free_bufs;
+
+	ret = spinand_manufacturer_init(spinand);
+	if (ret) {
+		dev_err(dev,
+			"Failed to initialize the SPI NAND chip (err = %d)\n",
+			ret);
+		goto err_free_bufs;
+	}
+
+	/* After power up, all blocks are locked, so unlock them here. */
+	for (i = 0; i < nand->memorg.ntargets; i++) {
+		ret = spinand_select_target(spinand, i);
+		if (ret)
+			goto err_free_bufs;
+
+		ret = spinand_lock_block(spinand, BL_ALL_UNLOCKED);
+		if (ret)
+			goto err_free_bufs;
+	}
+
+	ret = nanddev_init(nand, &spinand_ops, THIS_MODULE);
+	if (ret)
+		goto err_manuf_cleanup;
+
+	/*
+	 * Right now, we don't support ECC, so let the whole oob
+	 * area is available for user.
+	 */
+	mtd->_read_oob = spinand_mtd_read;
+	mtd->_write_oob = spinand_mtd_write;
+	mtd->_block_isbad = spinand_mtd_block_isbad;
+	mtd->_block_markbad = spinand_mtd_block_markbad;
+	mtd->_block_isreserved = spinand_mtd_block_isreserved;
+	mtd->_erase = spinand_mtd_erase;
+
+	if (spinand->eccinfo.ooblayout)
+		mtd_set_ooblayout(mtd, spinand->eccinfo.ooblayout);
+	else
+		mtd_set_ooblayout(mtd, &spinand_noecc_ooblayout);
+
+	ret = mtd_ooblayout_count_freebytes(mtd);
+	if (ret < 0)
+		goto err_cleanup_nanddev;
+
+	mtd->oobavail = ret;
+
+	return 0;
+
+err_cleanup_nanddev:
+	nanddev_cleanup(nand);
+
+err_manuf_cleanup:
+	spinand_manufacturer_cleanup(spinand);
+
+err_free_bufs:
+	kfree(spinand->databuf);
+	kfree(spinand->scratchbuf);
+	return ret;
+}
+
+static void spinand_cleanup(struct spinand_device *spinand)
+{
+	struct nand_device *nand = spinand_to_nand(spinand);
+
+	nanddev_cleanup(nand);
+	spinand_manufacturer_cleanup(spinand);
+	kfree(spinand->databuf);
+	kfree(spinand->scratchbuf);
+}
+
+static int spinand_probe(struct spi_mem *mem)
+{
+	struct spinand_device *spinand;
+	struct mtd_info *mtd;
+	int ret;
+
+	spinand = devm_kzalloc(&mem->spi->dev, sizeof(*spinand),
+			       GFP_KERNEL);
+	if (!spinand)
+		return -ENOMEM;
+
+	spinand->spimem = mem;
+	spi_mem_set_drvdata(mem, spinand);
+	spinand_set_of_node(spinand, mem->spi->dev.of_node);
+	mutex_init(&spinand->lock);
+	mtd = spinand_to_mtd(spinand);
+	mtd->dev.parent = &mem->spi->dev;
+
+	ret = spinand_init(spinand);
+	if (ret)
+		return ret;
+
+	ret = mtd_device_register(mtd, NULL, 0);
+	if (ret)
+		goto err_spinand_cleanup;
+
+	return 0;
+
+err_spinand_cleanup:
+	spinand_cleanup(spinand);
+
+	return ret;
+}
+
+static int spinand_remove(struct spi_mem *mem)
+{
+	struct spinand_device *spinand;
+	struct mtd_info *mtd;
+	int ret;
+
+	spinand = spi_mem_get_drvdata(mem);
+	mtd = spinand_to_mtd(spinand);
+
+	ret = mtd_device_unregister(mtd);
+	if (ret)
+		return ret;
+
+	spinand_cleanup(spinand);
+
+	return 0;
+}
+
+static const struct spi_device_id spinand_ids[] = {
+	{ .name = "spi-nand" },
+	{ /* sentinel */ },
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id spinand_of_ids[] = {
+	{ .compatible = "spi-nand" },
+	{ /* sentinel */ },
+};
+#endif
+
+static struct spi_mem_driver spinand_drv = {
+	.spidrv = {
+		.id_table = spinand_ids,
+		.driver = {
+			.name = "spi-nand",
+			.of_match_table = of_match_ptr(spinand_of_ids),
+		},
+	},
+	.probe = spinand_probe,
+	.remove = spinand_remove,
+};
+module_spi_mem_driver(spinand_drv);
+
+MODULE_DESCRIPTION("SPI NAND framework");
+MODULE_AUTHOR("Peter Pan<peterpandong@micron.com>");
+MODULE_LICENSE("GPL v2");

include/linux/mtd/spinand.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2016-2017 Micron Technology, Inc.
+ *
+ *  Authors:
+ *	Peter Pan <peterpandong@micron.com>
+ */
+#ifndef __LINUX_MTD_SPINAND_H
+#define __LINUX_MTD_SPINAND_H
+
+#include <linux/mutex.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+
+/**
+ * Standard SPI NAND flash operations
+ */
+
+#define SPINAND_RESET_OP						\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0xff, 1),				\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPINAND_WR_EN_DIS_OP(enable)					\
+	SPI_MEM_OP(SPI_MEM_OP_CMD((enable) ? 0x06 : 0x04, 1),		\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPINAND_READID_OP(ndummy, buf, len)				\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0x9f, 1),				\
+		   SPI_MEM_OP_NO_ADDR,					\
+		   SPI_MEM_OP_DUMMY(ndummy, 1),				\
+		   SPI_MEM_OP_DATA_IN(len, buf, 1))
+
+#define SPINAND_SET_FEATURE_OP(reg, valptr)				\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0x1f, 1),				\
+		   SPI_MEM_OP_ADDR(1, reg, 1),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(1, valptr, 1))
+
+#define SPINAND_GET_FEATURE_OP(reg, valptr)				\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0x0f, 1),				\
+		   SPI_MEM_OP_ADDR(1, reg, 1),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_IN(1, valptr, 1))
+
+#define SPINAND_BLK_ERASE_OP(addr)					\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0xd8, 1),				\
+		   SPI_MEM_OP_ADDR(3, addr, 1),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPINAND_PAGE_READ_OP(addr)					\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0x13, 1),				\
+		   SPI_MEM_OP_ADDR(3, addr, 1),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPINAND_PAGE_READ_FROM_CACHE_OP(fast, addr, ndummy, buf, len)	\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(fast ? 0x0b : 0x03, 1),		\
+		   SPI_MEM_OP_ADDR(2, addr, 1),				\
+		   SPI_MEM_OP_DUMMY(ndummy, 1),				\
+		   SPI_MEM_OP_DATA_IN(len, buf, 1))
+
+#define SPINAND_PAGE_READ_FROM_CACHE_X2_OP(addr, ndummy, buf, len)	\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0x3b, 1),				\
+		   SPI_MEM_OP_ADDR(2, addr, 1),				\
+		   SPI_MEM_OP_DUMMY(ndummy, 1),				\
+		   SPI_MEM_OP_DATA_IN(len, buf, 2))
+
+#define SPINAND_PAGE_READ_FROM_CACHE_X4_OP(addr, ndummy, buf, len)	\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0x6b, 1),				\
+		   SPI_MEM_OP_ADDR(2, addr, 1),				\
+		   SPI_MEM_OP_DUMMY(ndummy, 1),				\
+		   SPI_MEM_OP_DATA_IN(len, buf, 4))
+
+#define SPINAND_PAGE_READ_FROM_CACHE_DUALIO_OP(addr, ndummy, buf, len)	\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0xbb, 1),				\
+		   SPI_MEM_OP_ADDR(2, addr, 2),				\
+		   SPI_MEM_OP_DUMMY(ndummy, 2),				\
+		   SPI_MEM_OP_DATA_IN(len, buf, 2))
+
+#define SPINAND_PAGE_READ_FROM_CACHE_QUADIO_OP(addr, ndummy, buf, len)	\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0xeb, 1),				\
+		   SPI_MEM_OP_ADDR(2, addr, 4),				\
+		   SPI_MEM_OP_DUMMY(ndummy, 4),				\
+		   SPI_MEM_OP_DATA_IN(len, buf, 4))
+
+#define SPINAND_PROG_EXEC_OP(addr)					\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(0x10, 1),				\
+		   SPI_MEM_OP_ADDR(3, addr, 1),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_NO_DATA)
+
+#define SPINAND_PROG_LOAD(reset, addr, buf, len)			\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(reset ? 0x02 : 0x84, 1),		\
+		   SPI_MEM_OP_ADDR(2, addr, 1),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(len, buf, 1))
+
+#define SPINAND_PROG_LOAD_X4(reset, addr, buf, len)			\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(reset ? 0x32 : 0x34, 1),		\
+		   SPI_MEM_OP_ADDR(2, addr, 1),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(len, buf, 4))
+
+/**
+ * Standard SPI NAND flash commands
+ */
+#define SPINAND_CMD_PROG_LOAD_X4		0x32
+#define SPINAND_CMD_PROG_LOAD_RDM_DATA_X4	0x34
+
+/* feature register */
+#define REG_BLOCK_LOCK		0xa0
+#define BL_ALL_UNLOCKED		0x00
+
+/* configuration register */
+#define REG_CFG			0xb0
+#define CFG_OTP_ENABLE		BIT(6)
+#define CFG_ECC_ENABLE		BIT(4)
+#define CFG_QUAD_ENABLE		BIT(0)
+
+/* status register */
+#define REG_STATUS		0xc0
+#define STATUS_BUSY		BIT(0)
+#define STATUS_ERASE_FAILED	BIT(2)
+#define STATUS_PROG_FAILED	BIT(3)
+#define STATUS_ECC_MASK		GENMASK(5, 4)
+#define STATUS_ECC_NO_BITFLIPS	(0 << 4)
+#define STATUS_ECC_HAS_BITFLIPS	(1 << 4)
+#define STATUS_ECC_UNCOR_ERROR	(2 << 4)
+
+struct spinand_op;
+struct spinand_device;
+
+#define SPINAND_MAX_ID_LEN	4
+
+/**
+ * struct spinand_id - SPI NAND id structure
+ * @data: buffer containing the id bytes. Currently 4 bytes large, but can
+ *	  be extended if required
+ * @len: ID length
+ *
+ * struct_spinand_id->data contains all bytes returned after a READ_ID command,
+ * including dummy bytes if the chip does not emit ID bytes right after the
+ * READ_ID command. The responsibility to extract real ID bytes is left to
+ * struct_manufacurer_ops->detect().
+ */
+struct spinand_id {
+	u8 data[SPINAND_MAX_ID_LEN];
+	int len;
+};
+
+/**
+ * struct manufacurer_ops - SPI NAND manufacturer specific operations
+ * @detect: detect a SPI NAND device. Every time a SPI NAND device is probed
+ *	    the core calls the struct_manufacurer_ops->detect() hook of each
+ *	    registered manufacturer until one of them return 1. Note that
+ *	    the first thing to check in this hook is that the manufacturer ID
+ *	    in struct_spinand_device->id matches the manufacturer whose
+ *	    ->detect() hook has been called. Should return 1 if there's a
+ *	    match, 0 if the manufacturer ID does not match and a negative
+ *	    error code otherwise. When true is returned, the core assumes
+ *	    that properties of the NAND chip (spinand->base.memorg and
+ *	    spinand->base.eccreq) have been filled
+ * @init: initialize a SPI NAND device
+ * @cleanup: cleanup a SPI NAND device
+ *
+ * Each SPI NAND manufacturer driver should implement this interface so that
+ * NAND chips coming from this vendor can be detected and initialized properly.
+ */
+struct spinand_manufacturer_ops {
+	int (*detect)(struct spinand_device *spinand);
+	int (*init)(struct spinand_device *spinand);
+	void (*cleanup)(struct spinand_device *spinand);
+};
+
+/**
+ * struct spinand_manufacturer - SPI NAND manufacturer instance
+ * @id: manufacturer ID
+ * @name: manufacturer name
+ * @ops: manufacturer operations
+ */
+struct spinand_manufacturer {
+	u8 id;
+	char *name;
+	const struct spinand_manufacturer_ops *ops;
+};
+
+/**
+ * struct spinand_op_variants - SPI NAND operation variants
+ * @ops: the list of variants for a given operation
+ * @nops: the number of variants
+ *
+ * Some operations like read-from-cache/write-to-cache have several variants
+ * depending on the number of IO lines you use to transfer data or address
+ * cycles. This structure is a way to describe the different variants supported
+ * by a chip and let the core pick the best one based on the SPI mem controller
+ * capabilities.
+ */
+struct spinand_op_variants {
+	const struct spi_mem_op *ops;
+	unsigned int nops;
+};
+
+#define SPINAND_OP_VARIANTS(name, ...)					\
+	const struct spinand_op_variants name = {			\
+		.ops = (struct spi_mem_op[]) { __VA_ARGS__ },		\
+		.nops = sizeof((struct spi_mem_op[]){ __VA_ARGS__ }) /	\
+			sizeof(struct spi_mem_op),			\
+	}
+
+/**
+ * spinand_ecc_info - description of the on-die ECC implemented by a SPI NAND
+ *		      chip
+ * @get_status: get the ECC status. Should return a positive number encoding
+ *		the number of corrected bitflips if correction was possible or
+ *		-EBADMSG if there are uncorrectable errors. I can also return
+ *		other negative error codes if the error is not caused by
+ *		uncorrectable bitflips
+ * @ooblayout: the OOB layout used by the on-die ECC implementation
+ */
+struct spinand_ecc_info {
+	int (*get_status)(struct spinand_device *spinand, u8 status);
+	const struct mtd_ooblayout_ops *ooblayout;
+};
+
+#define SPINAND_HAS_QE_BIT		BIT(0)
+
+/**
+ * struct spinand_info - Structure used to describe SPI NAND chips
+ * @model: model name
+ * @devid: device ID
+ * @flags: OR-ing of the SPINAND_XXX flags
+ * @memorg: memory organization
+ * @eccreq: ECC requirements
+ * @eccinfo: on-die ECC info
+ * @op_variants: operations variants
+ * @op_variants.read_cache: variants of the read-cache operation
+ * @op_variants.write_cache: variants of the write-cache operation
+ * @op_variants.update_cache: variants of the update-cache operation
+ * @select_target: function used to select a target/die. Required only for
+ *		   multi-die chips
+ *
+ * Each SPI NAND manufacturer driver should have a spinand_info table
+ * describing all the chips supported by the driver.
+ */
+struct spinand_info {
+	const char *model;
+	u8 devid;
+	u32 flags;
+	struct nand_memory_organization memorg;
+	struct nand_ecc_req eccreq;
+	struct spinand_ecc_info eccinfo;
+	struct {
+		const struct spinand_op_variants *read_cache;
+		const struct spinand_op_variants *write_cache;
+		const struct spinand_op_variants *update_cache;
+	} op_variants;
+	int (*select_target)(struct spinand_device *spinand,
+			     unsigned int target);
+};
+
+#define SPINAND_INFO_OP_VARIANTS(__read, __write, __update)		\
+	{								\
+		.read_cache = __read,					\
+		.write_cache = __write,					\
+		.update_cache = __update,				\
+	}
+
+#define SPINAND_ECCINFO(__ooblayout, __get_status)			\
+	.eccinfo = {							\
+		.ooblayout = __ooblayout,				\
+		.get_status = __get_status,				\
+	}
+
+#define SPINAND_SELECT_TARGET(__func)					\
+	.select_target = __func,
+
+#define SPINAND_INFO(__model, __id, __memorg, __eccreq, __op_variants,	\
+		     __flags, ...)					\
+	{								\
+		.model = __model,					\
+		.devid = __id,						\
+		.memorg = __memorg,					\
+		.eccreq = __eccreq,					\
+		.op_variants = __op_variants,				\
+		.flags = __flags,					\
+		__VA_ARGS__						\
+	}
+
+/**
+ * struct spinand_device - SPI NAND device instance
+ * @base: NAND device instance
+ * @spimem: pointer to the SPI mem object
+ * @lock: lock used to serialize accesses to the NAND
+ * @id: NAND ID as returned by READ_ID
+ * @flags: NAND flags
+ * @op_templates: various SPI mem op templates
+ * @op_templates.read_cache: read cache op template
+ * @op_templates.write_cache: write cache op template
+ * @op_templates.update_cache: update cache op template
+ * @select_target: select a specific target/die. Usually called before sending
+ *		   a command addressing a page or an eraseblock embedded in
+ *		   this die. Only required if your chip exposes several dies
+ * @cur_target: currently selected target/die
+ * @eccinfo: on-die ECC information
+ * @cfg_cache: config register cache. One entry per die
+ * @databuf: bounce buffer for data
+ * @oobbuf: bounce buffer for OOB data
+ * @scratchbuf: buffer used for everything but page accesses. This is needed
+ *		because the spi-mem interface explicitly requests that buffers
+ *		passed in spi_mem_op be DMA-able, so we can't based the bufs on
+ *		the stack
+ * @manufacturer: SPI NAND manufacturer information
+ * @priv: manufacturer private data
+ */
+struct spinand_device {
+	struct nand_device base;
+	struct spi_mem *spimem;
+	struct mutex lock;
+	struct spinand_id id;
+	u32 flags;
+
+	struct {
+		const struct spi_mem_op *read_cache;
+		const struct spi_mem_op *write_cache;
+		const struct spi_mem_op *update_cache;
+	} op_templates;
+
+	int (*select_target)(struct spinand_device *spinand,
+			     unsigned int target);
+	unsigned int cur_target;
+
+	struct spinand_ecc_info eccinfo;
+
+	u8 *cfg_cache;
+	u8 *databuf;
+	u8 *oobbuf;
+	u8 *scratchbuf;
+	const struct spinand_manufacturer *manufacturer;
+	void *priv;
+};
+
+/**
+ * mtd_to_spinand() - Get the SPI NAND device attached to an MTD instance
+ * @mtd: MTD instance
+ *
+ * Return: the SPI NAND device attached to @mtd.
+ */
+static inline struct spinand_device *mtd_to_spinand(struct mtd_info *mtd)
+{
+	return container_of(mtd_to_nanddev(mtd), struct spinand_device, base);
+}
+
+/**
+ * spinand_to_mtd() - Get the MTD device embedded in a SPI NAND device
+ * @spinand: SPI NAND device
+ *
+ * Return: the MTD device embedded in @spinand.
+ */
+static inline struct mtd_info *spinand_to_mtd(struct spinand_device *spinand)
+{
+	return nanddev_to_mtd(&spinand->base);
+}
+
+/**
+ * nand_to_spinand() - Get the SPI NAND device embedding an NAND object
+ * @nand: NAND object
+ *
+ * Return: the SPI NAND device embedding @nand.
+ */
+static inline struct spinand_device *nand_to_spinand(struct nand_device *nand)
+{
+	return container_of(nand, struct spinand_device, base);
+}
+
+/**
+ * spinand_to_nand() - Get the NAND device embedded in a SPI NAND object
+ * @spinand: SPI NAND device
+ *
+ * Return: the NAND device embedded in @spinand.
+ */
+static inline struct nand_device *
+spinand_to_nand(struct spinand_device *spinand)
+{
+	return &spinand->base;
+}
+
+/**
+ * spinand_set_of_node - Attach a DT node to a SPI NAND device
+ * @spinand: SPI NAND device
+ * @np: DT node
+ *
+ * Attach a DT node to a SPI NAND device.
+ */
+static inline void spinand_set_of_node(struct spinand_device *spinand,
+				       struct device_node *np)
+{
+	nanddev_set_of_node(&spinand->base, np);
+}
+
+int spinand_match_and_init(struct spinand_device *dev,
+			   const struct spinand_info *table,
+			   unsigned int table_size, u8 devid);
+
+int spinand_upd_cfg(struct spinand_device *spinand, u8 mask, u8 val);
+int spinand_select_target(struct spinand_device *spinand, unsigned int target);
+
+#endif /* __LINUX_MTD_SPINAND_H */

include/linux/spi/spi-mem.h

@@ -3,7 +3,9 @@
  * Copyright (C) 2018 Exceet Electronics GmbH
  * Copyright (C) 2018 Bootlin
  *
- * Author: Boris Brezillon <boris.brezillon@bootlin.com>
+ * Author:
+ *	Peter Pan <peterpandong@micron.com>
+ *	Boris Brezillon <boris.brezillon@bootlin.com>
  */
 
 #ifndef __LINUX_SPI_MEM_H