diff options
author | Miquel Raynal <miquel.raynal@bootlin.com> | 2020-08-27 10:51:56 +0200 |
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committer | Miquel Raynal <miquel.raynal@bootlin.com> | 2020-09-02 09:28:15 +0200 |
commit | a8c7ffdb5fdde3a57c0b654f66f4d81325abe69f (patch) | |
tree | 8efed3aacb084db560bfb9e5f04f074fb7073391 /include/linux/mtd/nand.h | |
parent | b440915af2e41daff7ee33e1d0ec29af5c37a1bf (diff) |
mtd: nand: Introduce the ECC engine framework
Create a generic ECC engine framework. This is a base to instantiate ECC
engine objects.
If we really want to be generic, bindings must evolve, so here is the
new logic. The following three properties are mutually exclusive:
- The nand-no-ecc-engine boolean property is set and there is no
ECC engine to retrieve.
- The nand-use-soft-ecc-engine boolean property is set and the core
will force using the use of software correction.
- There is a nand-ecc-engine property pointing at a node which will
act as ECC engine.
It the later case, the property may reference:
- The NAND chip node itself (for the on-die ECC case).
- The parent node if the NAND controller embeds an ECC engine.
- Any other node being an external ECC controller as well.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200827085208.16276-9-miquel.raynal@bootlin.com
Diffstat (limited to 'include/linux/mtd/nand.h')
-rw-r--r-- | include/linux/mtd/nand.h | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index e754a6fc8a4b..8cf5bdbea782 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -127,6 +127,40 @@ 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 @@ -143,16 +177,27 @@ enum nand_ecc_algo { /** * 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: Number of bytes per step + * @flags: Misc properties */ 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 @@ -184,6 +229,75 @@ struct nand_ops { }; /** + * struct nand_ecc_context - Context for the ECC engine + * @conf: basic ECC engine parameters + * @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 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); +}; + +/** + * struct nand_ecc_engine - ECC engine abstraction for NAND devices + * @ops: ECC engine operations + */ +struct nand_ecc_engine { + struct nand_ecc_engine_ops *ops; +}; + +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); + +/** + * 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 |