diff options
Diffstat (limited to 'drivers/mtd/nand/core.c')
| -rw-r--r-- | drivers/mtd/nand/core.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/drivers/mtd/nand/core.c b/drivers/mtd/nand/core.c new file mode 100644 index 000000000000..d0cd6f8635d7 --- /dev/null +++ b/drivers/mtd/nand/core.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2017 Free Electrons + * + * Authors: + * Boris Brezillon <boris.brezillon@free-electrons.com> + * Peter Pan <peterpandong@micron.com> + */ + +#define pr_fmt(fmt) "nand: " fmt + +#include <linux/module.h> +#include <linux/mtd/nand.h> + +/** + * nanddev_isbad() - Check if a block is bad + * @nand: NAND device + * @pos: position pointing to the block we want to check + * + * Return: true if the block is bad, false otherwise. + */ +bool nanddev_isbad(struct nand_device *nand, const struct nand_pos *pos) +{ + if (nanddev_bbt_is_initialized(nand)) { + unsigned int entry; + int status; + + entry = nanddev_bbt_pos_to_entry(nand, pos); + status = nanddev_bbt_get_block_status(nand, entry); + /* Lazy block status retrieval */ + if (status == NAND_BBT_BLOCK_STATUS_UNKNOWN) { + if (nand->ops->isbad(nand, pos)) + status = NAND_BBT_BLOCK_FACTORY_BAD; + else + status = NAND_BBT_BLOCK_GOOD; + + nanddev_bbt_set_block_status(nand, entry, status); + } + + if (status == NAND_BBT_BLOCK_WORN || + status == NAND_BBT_BLOCK_FACTORY_BAD) + return true; + + return false; + } + + return nand->ops->isbad(nand, pos); +} +EXPORT_SYMBOL_GPL(nanddev_isbad); + +/** + * nanddev_markbad() - Mark a block as bad + * @nand: NAND device + * @pos: position of the block to mark bad + * + * Mark a block bad. This function is updating the BBT if available and + * calls the low-level markbad hook (nand->ops->markbad()). + * + * Return: 0 in case of success, a negative error code otherwise. + */ +int nanddev_markbad(struct nand_device *nand, const struct nand_pos *pos) +{ + struct mtd_info *mtd = nanddev_to_mtd(nand); + unsigned int entry; + int ret = 0; + + if (nanddev_isbad(nand, pos)) + return 0; + + ret = nand->ops->markbad(nand, pos); + if (ret) + pr_warn("failed to write BBM to block @%llx (err = %d)\n", + nanddev_pos_to_offs(nand, pos), ret); + + if (!nanddev_bbt_is_initialized(nand)) + goto out; + + entry = nanddev_bbt_pos_to_entry(nand, pos); + ret = nanddev_bbt_set_block_status(nand, entry, NAND_BBT_BLOCK_WORN); + if (ret) + goto out; + + ret = nanddev_bbt_update(nand); + +out: + if (!ret) + mtd->ecc_stats.badblocks++; + + return ret; +} +EXPORT_SYMBOL_GPL(nanddev_markbad); + +/** + * nanddev_isreserved() - Check whether an eraseblock is reserved or not + * @nand: NAND device + * @pos: NAND position to test + * + * Checks whether the eraseblock pointed by @pos is reserved or not. + * + * Return: true if the eraseblock is reserved, false otherwise. + */ +bool nanddev_isreserved(struct nand_device *nand, const struct nand_pos *pos) +{ + unsigned int entry; + int status; + + if (!nanddev_bbt_is_initialized(nand)) + return false; + + /* Return info from the table */ + entry = nanddev_bbt_pos_to_entry(nand, pos); + status = nanddev_bbt_get_block_status(nand, entry); + return status == NAND_BBT_BLOCK_RESERVED; +} +EXPORT_SYMBOL_GPL(nanddev_isreserved); + +/** + * nanddev_erase() - Erase a NAND portion + * @nand: NAND device + * @pos: position of the block to erase + * + * Erases the block if it's not bad. + * + * Return: 0 in case of success, a negative error code otherwise. + */ +int nanddev_erase(struct nand_device *nand, const struct nand_pos *pos) +{ + if (nanddev_isbad(nand, pos) || nanddev_isreserved(nand, pos)) { + pr_warn("attempt to erase a bad/reserved block @%llx\n", + nanddev_pos_to_offs(nand, pos)); + return -EIO; + } + + return nand->ops->erase(nand, pos); +} +EXPORT_SYMBOL_GPL(nanddev_erase); + +/** + * nanddev_mtd_erase() - Generic mtd->_erase() implementation for NAND devices + * @mtd: MTD device + * @einfo: erase request + * + * This is a simple mtd->_erase() implementation iterating over all blocks + * concerned by @einfo and calling nand->ops->erase() on each of them. + * + * Note that mtd->_erase should not be directly assigned to this helper, + * because there's no locking here. NAND specialized layers should instead + * implement there own wrapper around nanddev_mtd_erase() taking the + * appropriate lock before calling nanddev_mtd_erase(). + * + * Return: 0 in case of success, a negative error code otherwise. + */ +int nanddev_mtd_erase(struct mtd_info *mtd, struct erase_info *einfo) +{ + struct nand_device *nand = mtd_to_nanddev(mtd); + struct nand_pos pos, last; + int ret; + + nanddev_offs_to_pos(nand, einfo->addr, &pos); + nanddev_offs_to_pos(nand, einfo->addr + einfo->len - 1, &last); + while (nanddev_pos_cmp(&pos, &last) <= 0) { + ret = nanddev_erase(nand, &pos); + if (ret) { + einfo->fail_addr = nanddev_pos_to_offs(nand, &pos); + einfo->state = MTD_ERASE_FAILED; + + return ret; + } + + nanddev_pos_next_eraseblock(nand, &pos); + } + + einfo->state = MTD_ERASE_DONE; + + return 0; +} +EXPORT_SYMBOL_GPL(nanddev_mtd_erase); + +/** + * nanddev_init() - Initialize a NAND device + * @nand: NAND device + * @ops: NAND device operations + * @owner: NAND device owner + * + * Initializes a NAND device object. Consistency checks are done on @ops and + * @nand->memorg. Also takes care of initializing the BBT. + * + * Return: 0 in case of success, a negative error code otherwise. + */ +int nanddev_init(struct nand_device *nand, const struct nand_ops *ops, + struct module *owner) +{ + struct mtd_info *mtd = nanddev_to_mtd(nand); + struct nand_memory_organization *memorg = nanddev_get_memorg(nand); + + if (!nand || !ops) + return -EINVAL; + + if (!ops->erase || !ops->markbad || !ops->isbad) + return -EINVAL; + + if (!memorg->bits_per_cell || !memorg->pagesize || + !memorg->pages_per_eraseblock || !memorg->eraseblocks_per_lun || + !memorg->planes_per_lun || !memorg->luns_per_target || + !memorg->ntargets) + return -EINVAL; + + nand->rowconv.eraseblock_addr_shift = + fls(memorg->pages_per_eraseblock - 1); + nand->rowconv.lun_addr_shift = fls(memorg->eraseblocks_per_lun - 1) + + nand->rowconv.eraseblock_addr_shift; + + nand->ops = ops; + + mtd->type = memorg->bits_per_cell == 1 ? + MTD_NANDFLASH : MTD_MLCNANDFLASH; + mtd->flags = MTD_CAP_NANDFLASH; + mtd->erasesize = memorg->pagesize * memorg->pages_per_eraseblock; + mtd->writesize = memorg->pagesize; + mtd->writebufsize = memorg->pagesize; + mtd->oobsize = memorg->oobsize; + mtd->size = nanddev_size(nand); + mtd->owner = owner; + + return nanddev_bbt_init(nand); +} +EXPORT_SYMBOL_GPL(nanddev_init); + +/** + * nanddev_cleanup() - Release resources allocated in nanddev_init() + * @nand: NAND device + * + * Basically undoes what has been done in nanddev_init(). + */ +void nanddev_cleanup(struct nand_device *nand) +{ + if (nanddev_bbt_is_initialized(nand)) + nanddev_bbt_cleanup(nand); +} +EXPORT_SYMBOL_GPL(nanddev_cleanup); + +MODULE_DESCRIPTION("Generic NAND framework"); +MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>"); +MODULE_LICENSE("GPL v2"); |