This patch enables support for Toshiba BENAND. BENAND is a SLC NAND solution that automatically generates ECC inside NAND chip.
Some of the comments in the following discussion may need to be considerd. https://lkml.org/lkml/2015/3/25/310 Signed-off-by: KOBAYASHI Yoshitake <yoshitake.kobaya...@toshiba.co.jp> --- drivers/mtd/nand/Kconfig | 13 ++++ drivers/mtd/nand/Makefile | 1 + drivers/mtd/nand/nand_base.c | 32 +++++++++- drivers/mtd/nand/nand_benand.c | 137 +++++++++++++++++++++++++++++++++++++++ include/linux/mtd/nand.h | 3 + include/linux/mtd/nand_benand.h | 55 ++++++++++++++++ 6 files changed, 239 insertions(+), 2 deletions(-) create mode 100644 drivers/mtd/nand/nand_benand.c create mode 100644 include/linux/mtd/nand_benand.h diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index 5897d8d..050f0e9 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -22,6 +22,19 @@ menuconfig MTD_NAND if MTD_NAND +config MTD_NAND_BENAND + tristate + depends on MTD_NAND_BENAND_ENABLE + default MTD_NAND + +config MTD_NAND_BENAND_ENABLE + bool "Support for Toshiba BENAND (Built-in ECC NAND)" + default y + help + This enables support for Toshiba BENAND. + Toshiba BENAND is a SLC NAND solution that automatically + generates ECC inside NAND chip. + config MTD_NAND_BCH tristate select BCH diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile index 582bbd05..7f58bc1 100644 --- a/drivers/mtd/nand/Makefile +++ b/drivers/mtd/nand/Makefile @@ -3,6 +3,7 @@ # obj-$(CONFIG_MTD_NAND) += nand.o +obj-$(CONFIG_MTD_NAND_BENAND) += nand_benand.o obj-$(CONFIG_MTD_NAND_ECC) += nand_ecc.o obj-$(CONFIG_MTD_NAND_BCH) += nand_bch.o obj-$(CONFIG_MTD_NAND_IDS) += nand_ids.o diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index c2e1232..98a8932 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -43,6 +43,7 @@ #include <linux/mtd/nand.h> #include <linux/mtd/nand_ecc.h> #include <linux/mtd/nand_bch.h> +#include <linux/mtd/nand_benand.h> #include <linux/interrupt.h> #include <linux/bitops.h> #include <linux/leds.h> @@ -3526,8 +3527,17 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip, if (id_len >= 6 && id_data[0] == NAND_MFR_TOSHIBA && nand_is_slc(chip) && (id_data[5] & 0x7) == 0x6 /* 24nm */ && - !(id_data[4] & 0x80) /* !BENAND */) { - mtd->oobsize = 32 * mtd->writesize >> 9; + (id_data[4] & 0x80) /* BENAND */) { + pr_info("24nm BENAND\n"); + + if (IS_ENABLED(CONFIG_MTD_NAND_BENAND)) { + chip->ecc.mode = NAND_ECC_BENAND; + pr_info("Selected BENAND Driver\n"); + } + + } else { + pr_info("24nm SLC NAND\n"); + mtd->oobsize = 32 * mtd->writesize >> 9; /* !BENAND */ } } @@ -4075,6 +4085,24 @@ int nand_scan_tail(struct mtd_info *mtd) } break; + case NAND_ECC_BENAND: + if (!mtd_nand_has_benand()) { + pr_warn("CONFIG_MTD_NAND_BENAND not enabled\n"); + BUG(); + } + ecc->calculate = NULL; + ecc->correct = NULL; + ecc->read_page = nand_read_page_benand; + ecc->read_subpage = nand_read_subpage_benand; + ecc->write_page = nand_write_page_raw; + ecc->read_page_raw = nand_read_page_raw; + ecc->write_page_raw = nand_write_page_raw; + ecc->read_oob = nand_read_oob_std; + ecc->write_oob = nand_write_oob_std; + + nand_benand_init(mtd); + break; + case NAND_ECC_NONE: pr_warn("NAND_ECC_NONE selected by board driver. This is not recommended!\n"); ecc->read_page = nand_read_page_raw; diff --git a/drivers/mtd/nand/nand_benand.c b/drivers/mtd/nand/nand_benand.c new file mode 100644 index 0000000..56385b0 --- /dev/null +++ b/drivers/mtd/nand/nand_benand.c @@ -0,0 +1,137 @@ +/* + * drivers/mtd/nand_benand.c + * + * (C) Copyright Toshiba Corporation + * Semiconductor and Storage Products Company 2015 + * + * This program supports BENAND. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * + */ + +#include <linux/module.h> +#include <linux/mtd/nand.h> +#include <linux/mtd/nand_benand.h> + +static struct nand_ecclayout benand_oob_64 = { + .eccbytes = 0, + .eccpos = {}, + .oobfree = { + {.offset = 2, .length = 62} + } +}; + +static struct nand_ecclayout benand_oob_128 = { + .eccbytes = 0, + .eccpos = {}, + .oobfree = { + {.offset = 2, .length = 126} + } +}; + +void nand_benand_init(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd->priv; + + pr_info("%s\n", __func__); + + chip->ecc.size = mtd->writesize; + chip->ecc.strength = 1; + chip->options |= NAND_SUBPAGE_READ; + + switch (mtd->oobsize) { + case 64: + chip->ecc.layout = &benand_oob_64; + break; + case 128: + chip->ecc.layout = &benand_oob_128; + break; + default: + pr_warn("No oob scheme defined for oobsize %d\n", + mtd->oobsize); + BUG(); + } + +} +EXPORT_SYMBOL(nand_benand_init); + +int nand_read_page_benand(struct mtd_info *mtd, struct nand_chip *chip, + uint8_t *buf, int oob_required, int page) +{ + unsigned int max_bitflips = 0; + + pr_debug("%s\n", __func__); + + chip->ecc.read_page_raw(mtd, chip, buf, oob_required, page); + max_bitflips = nand_benand_status_chk(mtd, chip); + + return max_bitflips; +} +EXPORT_SYMBOL(nand_read_page_benand); + + +int nand_read_subpage_benand(struct mtd_info *mtd, struct nand_chip *chip, + uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi, + int page) +{ + uint8_t *p; + unsigned int max_bitflips = 0; + + pr_debug("%s\n", __func__); + + if (data_offs != 0) + chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_offs, -1); + + + p = bufpoi + data_offs; + chip->read_buf(mtd, p, readlen); + + max_bitflips = nand_benand_status_chk(mtd, chip); + + return max_bitflips; +} +EXPORT_SYMBOL(nand_read_subpage_benand); + + +int nand_benand_status_chk(struct mtd_info *mtd, struct nand_chip *chip) +{ + unsigned int bitflips = 0; + u8 status; + + pr_debug("%s\n", __func__); + + /* Check Read Status */ + chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1); + status = chip->read_byte(mtd); + + /* timeout */ + if (!(status & NAND_STATUS_READY)) { + pr_info("BENAND : Time Out!\n"); + return -EIO; + } + + /* uncorrectable */ + else if (status & NAND_STATUS_FAIL) { + pr_info("BENAND : Uncorrectable!\n"); + mtd->ecc_stats.failed++; + } + + /* correctable */ + else if (status & NAND_STATUS_RECOM_REWRT) { + pr_info("BENAND : Recommended to rewrite!\n"); + bitflips = chip->ecc.strength; + mtd->ecc_stats.corrected += chip->ecc.strength; + } + + return bitflips; + +} +EXPORT_SYMBOL(nand_benand_status_chk); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Toshiba Corporation Semiconductor and Storage Products Company"); +MODULE_DESCRIPTION("BENAND (Built-in ECC NAND) support"); diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 3d4ea7e..8f59ad9 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -101,6 +101,8 @@ extern int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len); /* Status bits */ #define NAND_STATUS_FAIL 0x01 #define NAND_STATUS_FAIL_N1 0x02 +/* Recommended to rewrite for BENAND */ +#define NAND_STATUS_RECOM_REWRT 0x08 #define NAND_STATUS_TRUE_READY 0x20 #define NAND_STATUS_READY 0x40 #define NAND_STATUS_WP 0x80 @@ -115,6 +117,7 @@ typedef enum { NAND_ECC_HW_SYNDROME, NAND_ECC_HW_OOB_FIRST, NAND_ECC_SOFT_BCH, + NAND_ECC_BENAND, } nand_ecc_modes_t; /* diff --git a/include/linux/mtd/nand_benand.h b/include/linux/mtd/nand_benand.h new file mode 100644 index 0000000..48fcc49 --- /dev/null +++ b/include/linux/mtd/nand_benand.h @@ -0,0 +1,55 @@ +/* + * linux/include/linux/mtd/nand_benand.h + * + * (C) Copyright Toshiba Corporation + * Semiconductor and Storage Products Company 2015 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#ifndef __MTD_NAND_BENAND_H__ +#define __MTD_NAND_BENAND_H__ + +#if defined(CONFIG_MTD_NAND_BENAND_ENABLE) + +static inline int mtd_nand_has_benand(void) { return 1; } + +void nand_benand_init(struct mtd_info *mtd); + +int nand_read_page_benand(struct mtd_info *mtd, struct nand_chip *chip, + uint8_t *buf, int oob_required, int page); + +int nand_read_subpage_benand(struct mtd_info *mtd, struct nand_chip *chip, + uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi, + int page); + +int nand_benand_status_chk(struct mtd_info *mtd, struct nand_chip *chipr); + +#else /* CONFIG_MTD_NAND_BENAND_ENABLE */ +static inline int mtd_nand_has_benand(void) { return 0; } + +void nand_benand_init(struct mtd_info *mtd) {} + +int nand_read_page_benand(struct mtd_info *mtd, struct nand_chip *chip, + uint8_t *buf, int oob_required, int page) +{ + return -1; +} + +int nand_read_subpage_benand(struct mtd_info *mtd, struct nand_chip *chip, + uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi, + int page) +{ + return -1; +} + +int nand_benand_status_chk(struct mtd_info *mtd, struct nand_chip *chipr) +{ + return -1; +} + +#endif /* CONFIG_MTD_NAND_BENAND_ENABLE */ +#endif -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
