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>
Acked-by: Jagan Teki <jagan@openedev.com>
diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
new file mode 100644
index 0000000..ad59fc0
--- /dev/null
+++ b/include/linux/mtd/spinand.h
@@ -0,0 +1,427 @@
+/* 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
+
+#ifndef __UBOOT__
+#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>
+#else
+#include <common.h>
+#include <spi.h>
+#include <spi-mem.h>
+#include <linux/mtd/nand.h>
+#endif
+
+/**
+ * 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
+ * @slave: pointer to the SPI slave 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;
+#ifndef __UBOOT__
+	struct spi_mem *spimem;
+	struct mutex lock;
+#else
+	struct spi_slave *slave;
+#endif
+	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,
+				       const 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 */