1 files changed, 314 insertions, 11 deletions

diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 0c7483843a32..c3693bb87b4c 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -12,6 +12,8 @@
 
 #include <linux/mtd/mtd.h>
 
+struct nand_device;
+
 /**
  * struct nand_memory_organization - Memory organization structure
  * @bits_per_cell: number of bits per NAND cell
@@ -81,7 +83,18 @@ struct nand_pos {
 };
 
 /**
+ * enum nand_page_io_req_type - Direction of an I/O request
+ * @NAND_PAGE_READ: from the chip, to the controller
+ * @NAND_PAGE_WRITE: from the controller, to the chip
+ */
+enum nand_page_io_req_type {
+	NAND_PAGE_READ = 0,
+	NAND_PAGE_WRITE,
+};
+
+/**
  * struct nand_page_io_req - NAND I/O request object
+ * @type: the type of page I/O: read or write
  * @pos: the position this I/O request is targeting
  * @dataoffs: the offset within the page
  * @datalen: number of data bytes to read from/write to this page
@@ -97,6 +110,7 @@ struct nand_pos {
  * specific commands/operations.
  */
 struct nand_page_io_req {
+	enum nand_page_io_req_type type;
 	struct nand_pos pos;
 	unsigned int dataoffs;
 	unsigned int datalen;
@@ -113,18 +127,77 @@ struct nand_page_io_req {
 	int mode;
 };
 
+const struct mtd_ooblayout_ops *nand_get_small_page_ooblayout(void);
+const struct mtd_ooblayout_ops *nand_get_large_page_ooblayout(void);
+const struct mtd_ooblayout_ops *nand_get_large_page_hamming_ooblayout(void);
+
+/**
+ * enum nand_ecc_engine_type - NAND ECC engine type
+ * @NAND_ECC_ENGINE_TYPE_INVALID: Invalid value
+ * @NAND_ECC_ENGINE_TYPE_NONE: No ECC correction
+ * @NAND_ECC_ENGINE_TYPE_SOFT: Software ECC correction
+ * @NAND_ECC_ENGINE_TYPE_ON_HOST: On host hardware ECC correction
+ * @NAND_ECC_ENGINE_TYPE_ON_DIE: On chip hardware ECC correction
+ */
+enum nand_ecc_engine_type {
+	NAND_ECC_ENGINE_TYPE_INVALID,
+	NAND_ECC_ENGINE_TYPE_NONE,
+	NAND_ECC_ENGINE_TYPE_SOFT,
+	NAND_ECC_ENGINE_TYPE_ON_HOST,
+	NAND_ECC_ENGINE_TYPE_ON_DIE,
+};
+
+/**
+ * enum nand_ecc_placement - NAND ECC bytes placement
+ * @NAND_ECC_PLACEMENT_UNKNOWN: The actual position of the ECC bytes is unknown
+ * @NAND_ECC_PLACEMENT_OOB: The ECC bytes are located in the OOB area
+ * @NAND_ECC_PLACEMENT_INTERLEAVED: Syndrome layout, there are ECC bytes
+ *                                  interleaved with regular data in the main
+ *                                  area
+ */
+enum nand_ecc_placement {
+	NAND_ECC_PLACEMENT_UNKNOWN,
+	NAND_ECC_PLACEMENT_OOB,
+	NAND_ECC_PLACEMENT_INTERLEAVED,
+};
+
+/**
+ * enum nand_ecc_algo - NAND ECC algorithm
+ * @NAND_ECC_ALGO_UNKNOWN: Unknown algorithm
+ * @NAND_ECC_ALGO_HAMMING: Hamming algorithm
+ * @NAND_ECC_ALGO_BCH: Bose-Chaudhuri-Hocquenghem algorithm
+ * @NAND_ECC_ALGO_RS: Reed-Solomon algorithm
+ */
+enum nand_ecc_algo {
+	NAND_ECC_ALGO_UNKNOWN,
+	NAND_ECC_ALGO_HAMMING,
+	NAND_ECC_ALGO_BCH,
+	NAND_ECC_ALGO_RS,
+};
+
 /**
- * struct nand_ecc_req - NAND ECC requirements
+ * struct nand_ecc_props - NAND ECC properties
+ * @engine_type: ECC engine type
+ * @placement: OOB placement (if relevant)
+ * @algo: ECC algorithm (if relevant)
  * @strength: ECC strength
- * @step_size: ECC step/block size
+ * @step_size: Number of bytes per step
+ * @flags: Misc properties
  */
-struct nand_ecc_req {
+struct nand_ecc_props {
+	enum nand_ecc_engine_type engine_type;
+	enum nand_ecc_placement placement;
+	enum nand_ecc_algo algo;
 	unsigned int strength;
 	unsigned int step_size;
+	unsigned int flags;
 };
 
 #define NAND_ECCREQ(str, stp) { .strength = (str), .step_size = (stp) }
 
+/* NAND ECC misc flags */
+#define NAND_ECC_MAXIMIZE_STRENGTH BIT(0)
+
 /**
  * struct nand_bbt - bad block table object
  * @cache: in memory BBT cache
@@ -133,8 +206,6 @@ struct nand_bbt {
 	unsigned long *cache;
 };
 
-struct nand_device;
-
 /**
  * struct nand_ops - NAND operations
  * @erase: erase a specific block. No need to check if the block is bad before
@@ -158,10 +229,177 @@ struct nand_ops {
 };
 
 /**
+ * struct nand_ecc_context - Context for the ECC engine
+ * @conf: basic ECC engine parameters
+ * @nsteps: number of ECC steps
+ * @total: total number of bytes used for storing ECC codes, this is used by
+ *         generic OOB layouts
+ * @priv: ECC engine driver private data
+ */
+struct nand_ecc_context {
+	struct nand_ecc_props conf;
+	unsigned int nsteps;
+	unsigned int total;
+	void *priv;
+};
+
+/**
+ * struct nand_ecc_engine_ops - ECC engine operations
+ * @init_ctx: given a desired user configuration for the pointed NAND device,
+ *            requests the ECC engine driver to setup a configuration with
+ *            values it supports.
+ * @cleanup_ctx: clean the context initialized by @init_ctx.
+ * @prepare_io_req: is called before reading/writing a page to prepare the I/O
+ *                  request to be performed with ECC correction.
+ * @finish_io_req: is called after reading/writing a page to terminate the I/O
+ *                 request and ensure proper ECC correction.
+ */
+struct nand_ecc_engine_ops {
+	int (*init_ctx)(struct nand_device *nand);
+	void (*cleanup_ctx)(struct nand_device *nand);
+	int (*prepare_io_req)(struct nand_device *nand,
+			      struct nand_page_io_req *req);
+	int (*finish_io_req)(struct nand_device *nand,
+			     struct nand_page_io_req *req);
+};
+
+/**
+ * enum nand_ecc_engine_integration - How the NAND ECC engine is integrated
+ * @NAND_ECC_ENGINE_INTEGRATION_INVALID: Invalid value
+ * @NAND_ECC_ENGINE_INTEGRATION_PIPELINED: Pipelined engine, performs on-the-fly
+ *                                         correction, does not need to copy
+ *                                         data around
+ * @NAND_ECC_ENGINE_INTEGRATION_EXTERNAL: External engine, needs to bring the
+ *                                        data into its own area before use
+ */
+enum nand_ecc_engine_integration {
+	NAND_ECC_ENGINE_INTEGRATION_INVALID,
+	NAND_ECC_ENGINE_INTEGRATION_PIPELINED,
+	NAND_ECC_ENGINE_INTEGRATION_EXTERNAL,
+};
+
+/**
+ * struct nand_ecc_engine - ECC engine abstraction for NAND devices
+ * @dev: Host device
+ * @node: Private field for registration time
+ * @ops: ECC engine operations
+ * @integration: How the engine is integrated with the host
+ *               (only relevant on %NAND_ECC_ENGINE_TYPE_ON_HOST engines)
+ * @priv: Private data
+ */
+struct nand_ecc_engine {
+	struct device *dev;
+	struct list_head node;
+	struct nand_ecc_engine_ops *ops;
+	enum nand_ecc_engine_integration integration;
+	void *priv;
+};
+
+void of_get_nand_ecc_user_config(struct nand_device *nand);
+int nand_ecc_init_ctx(struct nand_device *nand);
+void nand_ecc_cleanup_ctx(struct nand_device *nand);
+int nand_ecc_prepare_io_req(struct nand_device *nand,
+			    struct nand_page_io_req *req);
+int nand_ecc_finish_io_req(struct nand_device *nand,
+			   struct nand_page_io_req *req);
+bool nand_ecc_is_strong_enough(struct nand_device *nand);
+
+#if IS_REACHABLE(CONFIG_MTD_NAND_CORE)
+int nand_ecc_register_on_host_hw_engine(struct nand_ecc_engine *engine);
+int nand_ecc_unregister_on_host_hw_engine(struct nand_ecc_engine *engine);
+#else
+static inline int
+nand_ecc_register_on_host_hw_engine(struct nand_ecc_engine *engine)
+{
+	return -ENOTSUPP;
+}
+static inline int
+nand_ecc_unregister_on_host_hw_engine(struct nand_ecc_engine *engine)
+{
+	return -ENOTSUPP;
+}
+#endif
+
+struct nand_ecc_engine *nand_ecc_get_sw_engine(struct nand_device *nand);
+struct nand_ecc_engine *nand_ecc_get_on_die_hw_engine(struct nand_device *nand);
+struct nand_ecc_engine *nand_ecc_get_on_host_hw_engine(struct nand_device *nand);
+void nand_ecc_put_on_host_hw_engine(struct nand_device *nand);
+struct device *nand_ecc_get_engine_dev(struct device *host);
+
+#if IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING)
+struct nand_ecc_engine *nand_ecc_sw_hamming_get_engine(void);
+#else
+static inline struct nand_ecc_engine *nand_ecc_sw_hamming_get_engine(void)
+{
+	return NULL;
+}
+#endif /* CONFIG_MTD_NAND_ECC_SW_HAMMING */
+
+#if IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_BCH)
+struct nand_ecc_engine *nand_ecc_sw_bch_get_engine(void);
+#else
+static inline struct nand_ecc_engine *nand_ecc_sw_bch_get_engine(void)
+{
+	return NULL;
+}
+#endif /* CONFIG_MTD_NAND_ECC_SW_BCH */
+
+/**
+ * struct nand_ecc_req_tweak_ctx - Help for automatically tweaking requests
+ * @orig_req: Pointer to the original IO request
+ * @nand: Related NAND device, to have access to its memory organization
+ * @page_buffer_size: Real size of the page buffer to use (can be set by the
+ *                    user before the tweaking mechanism initialization)
+ * @oob_buffer_size: Real size of the OOB buffer to use (can be set by the
+ *                   user before the tweaking mechanism initialization)
+ * @spare_databuf: Data bounce buffer
+ * @spare_oobbuf: OOB bounce buffer
+ * @bounce_data: Flag indicating a data bounce buffer is used
+ * @bounce_oob: Flag indicating an OOB bounce buffer is used
+ */
+struct nand_ecc_req_tweak_ctx {
+	struct nand_page_io_req orig_req;
+	struct nand_device *nand;
+	unsigned int page_buffer_size;
+	unsigned int oob_buffer_size;
+	void *spare_databuf;
+	void *spare_oobbuf;
+	bool bounce_data;
+	bool bounce_oob;
+};
+
+int nand_ecc_init_req_tweaking(struct nand_ecc_req_tweak_ctx *ctx,
+			       struct nand_device *nand);
+void nand_ecc_cleanup_req_tweaking(struct nand_ecc_req_tweak_ctx *ctx);
+void nand_ecc_tweak_req(struct nand_ecc_req_tweak_ctx *ctx,
+			struct nand_page_io_req *req);
+void nand_ecc_restore_req(struct nand_ecc_req_tweak_ctx *ctx,
+			  struct nand_page_io_req *req);
+
+/**
+ * struct nand_ecc - Information relative to the ECC
+ * @defaults: Default values, depend on the underlying subsystem
+ * @requirements: ECC requirements from the NAND chip perspective
+ * @user_conf: User desires in terms of ECC parameters
+ * @ctx: ECC context for the ECC engine, derived from the device @requirements
+ *       the @user_conf and the @defaults
+ * @ondie_engine: On-die ECC engine reference, if any
+ * @engine: ECC engine actually bound
+ */
+struct nand_ecc {
+	struct nand_ecc_props defaults;
+	struct nand_ecc_props requirements;
+	struct nand_ecc_props user_conf;
+	struct nand_ecc_context ctx;
+	struct nand_ecc_engine *ondie_engine;
+	struct nand_ecc_engine *engine;
+};
+
+/**
  * struct nand_device - NAND device
  * @mtd: MTD instance attached to the NAND device
  * @memorg: memory layout
- * @eccreq: ECC requirements
+ * @ecc: NAND ECC object attached to the NAND device
  * @rowconv: position to row address converter
  * @bbt: bad block table info
  * @ops: NAND operations attached to the NAND device
@@ -169,8 +407,8 @@ struct nand_ops {
  * Generic NAND object. Specialized NAND layers (raw NAND, SPI NAND, OneNAND)
  * should declare their own NAND object embedding a nand_device struct (that's
  * how inheritance is done).
- * struct_nand_device->memorg and struct_nand_device->eccreq should be filled
- * at device detection time to reflect the NAND device
+ * struct_nand_device->memorg and struct_nand_device->ecc.requirements should
+ * be filled at device detection time to reflect the NAND device
  * capabilities/requirements. Once this is done nanddev_init() can be called.
  * It will take care of converting NAND information into MTD ones, which means
  * the specialized NAND layers should never manually tweak
@@ -179,7 +417,7 @@ struct nand_ops {
 struct nand_device {
 	struct mtd_info mtd;
 	struct nand_memory_organization memorg;
-	struct nand_ecc_req eccreq;
+	struct nand_ecc ecc;
 	struct nand_row_converter rowconv;
 	struct nand_bbt bbt;
 	const struct nand_ops *ops;
@@ -383,6 +621,60 @@ nanddev_get_memorg(struct nand_device *nand)
 	return &nand->memorg;
 }
 
+/**
+ * nanddev_get_ecc_conf() - Extract the ECC configuration from a NAND device
+ * @nand: NAND device
+ */
+static inline const struct nand_ecc_props *
+nanddev_get_ecc_conf(struct nand_device *nand)
+{
+	return &nand->ecc.ctx.conf;
+}
+
+/**
+ * nanddev_get_ecc_nsteps() - Extract the number of ECC steps
+ * @nand: NAND device
+ */
+static inline unsigned int
+nanddev_get_ecc_nsteps(struct nand_device *nand)
+{
+	return nand->ecc.ctx.nsteps;
+}
+
+/**
+ * nanddev_get_ecc_bytes_per_step() - Extract the number of ECC bytes per step
+ * @nand: NAND device
+ */
+static inline unsigned int
+nanddev_get_ecc_bytes_per_step(struct nand_device *nand)
+{
+	return nand->ecc.ctx.total / nand->ecc.ctx.nsteps;
+}
+
+/**
+ * nanddev_get_ecc_requirements() - Extract the ECC requirements from a NAND
+ *                                  device
+ * @nand: NAND device
+ */
+static inline const struct nand_ecc_props *
+nanddev_get_ecc_requirements(struct nand_device *nand)
+{
+	return &nand->ecc.requirements;
+}
+
+/**
+ * nanddev_set_ecc_requirements() - Assign the ECC requirements of a NAND
+ *                                  device
+ * @nand: NAND device
+ * @reqs: Requirements
+ */
+static inline void
+nanddev_set_ecc_requirements(struct nand_device *nand,
+			     const struct nand_ecc_props *reqs)
+{
+	nand->ecc.requirements = *reqs;
+}
+
 int nanddev_init(struct nand_device *nand, const struct nand_ops *ops,
 		 struct module *owner);
 void nanddev_cleanup(struct nand_device *nand);
@@ -624,11 +916,13 @@ static inline void nanddev_pos_next_page(struct nand_device *nand,
  * layer.
  */
 static inline void nanddev_io_iter_init(struct nand_device *nand,
+					enum nand_page_io_req_type reqtype,
 					loff_t offs, struct mtd_oob_ops *req,
 					struct nand_io_iter *iter)
 {
 	struct mtd_info *mtd = nanddev_to_mtd(nand);
 
+	iter->req.type = reqtype;
 	iter->req.mode = req->mode;
 	iter->req.dataoffs = nanddev_offs_to_pos(nand, offs, &iter->req.pos);
 	iter->req.ooboffs = req->ooboffs;
@@ -698,8 +992,8 @@ static inline bool nanddev_io_iter_end(struct nand_device *nand,
  *
  * Should be used for iterate over pages that are contained in an MTD request.
  */
-#define nanddev_io_for_each_page(nand, start, req, iter)		\
-	for (nanddev_io_iter_init(nand, start, req, iter);		\
+#define nanddev_io_for_each_page(nand, type, start, req, iter)		\
+	for (nanddev_io_iter_init(nand, type, start, req, iter);	\
 	     !nanddev_io_iter_end(nand, iter);				\
 	     nanddev_io_iter_next_page(nand, iter))
 
@@ -708,6 +1002,15 @@ bool nanddev_isreserved(struct nand_device *nand, const struct nand_pos *pos);
 int nanddev_erase(struct nand_device *nand, const struct nand_pos *pos);
 int nanddev_markbad(struct nand_device *nand, const struct nand_pos *pos);
 
+/* ECC related functions */
+int nanddev_ecc_engine_init(struct nand_device *nand);
+void nanddev_ecc_engine_cleanup(struct nand_device *nand);
+
+static inline void *nand_to_ecc_ctx(struct nand_device *nand)
+{
+	return nand->ecc.ctx.priv;
+}
+
 /* BBT related functions */
 enum nand_bbt_block_status {
 	NAND_BBT_BLOCK_STATUS_UNKNOWN,