From a2c65b47effcb3d0aa23e58596538acd338ac7c5 Mon Sep 17 00:00:00 2001 From: Sandeep Paulraj Date: Mon, 10 Aug 2009 13:27:46 -0400 Subject: NAND: ADD page Parameter to all read_page/read_page_raw API's This patch adds a new "page" parameter to all NAND read_page/read_page_raw APIs. The read_page API for the new mode ECC_HW_OOB_FIRST requires the page information to send the READOOB command and read the OOB area before the data area. This patch has been accepted by Andrew Morton and can be found at http://userweb.kernel.org/~akpm/mmotm/broken-out/mtd-nand-add-page-parameter-to-all-read_page-read_page_raw-apis.patch WE would like this to become part of the u-boot GIT as well Signed-off-by: Sandeep Paulraj Signed-off-by: Sneha Narnakaje Signed-off-by: Scott Wood --- drivers/mtd/nand/nand_base.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'drivers/mtd/nand/nand_base.c') diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 360b070..ca02628 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -895,7 +895,7 @@ static int nand_wait(struct mtd_info *mtd, struct nand_chip *this) * @buf: buffer to store read data */ static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip, - uint8_t *buf) + uint8_t *buf, int page) { chip->read_buf(mtd, buf, mtd->writesize); chip->read_buf(mtd, chip->oob_poi, mtd->oobsize); @@ -909,7 +909,7 @@ static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip, * @buf: buffer to store read data */ static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip, - uint8_t *buf) + uint8_t *buf, int page) { int i, eccsize = chip->ecc.size; int eccbytes = chip->ecc.bytes; @@ -919,7 +919,7 @@ static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip, uint8_t *ecc_code = chip->buffers->ecccode; uint32_t *eccpos = chip->ecc.layout->eccpos; - chip->ecc.read_page_raw(mtd, chip, buf); + chip->ecc.read_page_raw(mtd, chip, buf, page); for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) chip->ecc.calculate(mtd, p, &ecc_calc[i]); @@ -1032,7 +1032,7 @@ static int nand_read_subpage(struct mtd_info *mtd, struct nand_chip *chip, uint3 * Not for syndrome calculating ecc controllers which need a special oob layout */ static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip, - uint8_t *buf) + uint8_t *buf, int page) { int i, eccsize = chip->ecc.size; int eccbytes = chip->ecc.bytes; @@ -1077,7 +1077,7 @@ static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip, * we need a special oob layout and handling. */ static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip, - uint8_t *buf) + uint8_t *buf, int page) { int i, eccsize = chip->ecc.size; int eccbytes = chip->ecc.bytes; @@ -1219,11 +1219,13 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from, /* Now read the page into the buffer */ if (unlikely(ops->mode == MTD_OOB_RAW)) - ret = chip->ecc.read_page_raw(mtd, chip, bufpoi); + ret = chip->ecc.read_page_raw(mtd, chip, + bufpoi, page); else if (!aligned && NAND_SUBPAGE_READ(chip) && !oob) ret = chip->ecc.read_subpage(mtd, chip, col, bytes, bufpoi); else - ret = chip->ecc.read_page(mtd, chip, bufpoi); + ret = chip->ecc.read_page(mtd, chip, bufpoi, + page); if (ret < 0) break; -- cgit v1.1 From f83b7f9e8a5d1334e24506ea5953dd871596ea8a Mon Sep 17 00:00:00 2001 From: Sandeep Paulraj Date: Mon, 10 Aug 2009 13:27:56 -0400 Subject: MTD:NAND: ADD new ECC mode NAND_ECC_HW_OOB_FIRST This patch adds the new mode NAND_ECC_HW_OOB_FIRST in the nand code to support 4-bit ECC on TI DaVinci devices with large page (up to 2K) NAND chips. This ECC mode is similar to NAND_ECC_HW, with the exception of read_page API that first reads the OOB area, reads the data in chunks, feeds the ECC from OOB area to the ECC hw engine and perform any correction on the data as per the ECC status reported by the engine. This patch has been accepted by Andrew Morton and can be found at http://userweb.kernel.org/~akpm/mmotm/broken-out/mtd-nand-add-new-ecc-mode-ecc_hw_oob_first.patch Signed-off-by: Sandeep Paulraj Signed-off-by: Sneha Narnakaje Signed-off-by: Scott Wood --- drivers/mtd/nand/nand_base.c | 59 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) (limited to 'drivers/mtd/nand/nand_base.c') diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index ca02628..426bb95 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -1068,6 +1068,54 @@ static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip, } /** + * nand_read_page_hwecc_oob_first - [REPLACABLE] hw ecc, read oob first + * @mtd: mtd info structure + * @chip: nand chip info structure + * @buf: buffer to store read data + * + * Hardware ECC for large page chips, require OOB to be read first. + * For this ECC mode, the write_page method is re-used from ECC_HW. + * These methods read/write ECC from the OOB area, unlike the + * ECC_HW_SYNDROME support with multiple ECC steps, follows the + * "infix ECC" scheme and reads/writes ECC from the data area, by + * overwriting the NAND manufacturer bad block markings. + */ +static int nand_read_page_hwecc_oob_first(struct mtd_info *mtd, + struct nand_chip *chip, uint8_t *buf, int page) +{ + int i, eccsize = chip->ecc.size; + int eccbytes = chip->ecc.bytes; + int eccsteps = chip->ecc.steps; + uint8_t *p = buf; + uint8_t *ecc_code = chip->buffers->ecccode; + uint32_t *eccpos = chip->ecc.layout->eccpos; + uint8_t *ecc_calc = chip->buffers->ecccalc; + + /* Read the OOB area first */ + chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page); + chip->read_buf(mtd, chip->oob_poi, mtd->oobsize); + chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page); + + for (i = 0; i < chip->ecc.total; i++) + ecc_code[i] = chip->oob_poi[eccpos[i]]; + + for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) { + int stat; + + chip->ecc.hwctl(mtd, NAND_ECC_READ); + chip->read_buf(mtd, p, eccsize); + chip->ecc.calculate(mtd, p, &ecc_calc[i]); + + stat = chip->ecc.correct(mtd, p, &ecc_code[i], NULL); + if (stat < 0) + mtd->ecc_stats.failed++; + else + mtd->ecc_stats.corrected += stat; + } + return 0; +} + +/** * nand_read_page_syndrome - [REPLACABLE] hardware ecc syndrom based page read * @mtd: mtd info structure * @chip: nand chip info structure @@ -2730,6 +2778,17 @@ int nand_scan_tail(struct mtd_info *mtd) chip->ecc.write_page_raw = nand_write_page_raw; switch (chip->ecc.mode) { + case NAND_ECC_HW_OOB_FIRST: + /* Similar to NAND_ECC_HW, but a separate read_page handle */ + if (!chip->ecc.calculate || !chip->ecc.correct || + !chip->ecc.hwctl) { + printk(KERN_WARNING "No ECC functions supplied, " + "Hardware ECC not possible\n"); + BUG(); + } + if (!chip->ecc.read_page) + chip->ecc.read_page = nand_read_page_hwecc_oob_first; + case NAND_ECC_HW: /* Use standard hwecc read page function ? */ if (!chip->ecc.read_page) -- cgit v1.1