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author | Robert Jarzmik <robert.jarzmik@free.fr> | 2011-11-19 15:02:47 (GMT) |
---|---|---|
committer | David Woodhouse <David.Woodhouse@intel.com> | 2012-01-09 18:07:17 (GMT) |
commit | 32a50b3a457fda9606fd0946eb77ba28a520cd7f (patch) | |
tree | 43df59205d0b08e3257249df581f3202d44c8d02 /drivers | |
parent | 34db8a5a72c5c5eb5d2811f237dcc9bf3c6425a9 (diff) | |
download | linux-32a50b3a457fda9606fd0946eb77ba28a520cd7f.tar.xz |
mtd: docg3: fix reading oob+data without correction
Fix the docg3 reads to be able to cope with all possible
data buffer / oob buffer / file mode combinations from
docg3_read_oob().
This especially ensures that raw reads do not use ECC
corrections, and AUTOOOB and PLACEOOB do use ECC
correction.
The approach is to empty docg3_read() and make it a wrapper
to docg3_read_oob(). As docg3_read_oob() handles all the
funny cases (no data buffer but oob buffer, data buffer but
no oob buffer, ...), docg3_read() is just a special use of
docg3_read_oob().
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reviewed-by: Ivan Djelic <ivan.djelic@parrot.com>
Reviewed-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/mtd/devices/docg3.c | 194 |
1 files changed, 95 insertions, 99 deletions
diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c index 5834e6e..1c2f54d 100644 --- a/drivers/mtd/devices/docg3.c +++ b/drivers/mtd/devices/docg3.c @@ -196,8 +196,8 @@ static int doc_reset_seq(struct docg3 *docg3) /** * doc_read_data_area - Read data from data area * @docg3: the device - * @buf: the buffer to fill in - * @len: the lenght to read + * @buf: the buffer to fill in (might be NULL is dummy reads) + * @len: the length to read * @first: first time read, DOC_READADDRESS should be set * * Reads bytes from flash data. Handles the single byte / even bytes reads. @@ -218,8 +218,10 @@ static void doc_read_data_area(struct docg3 *docg3, void *buf, int len, dst16 = buf; for (i = 0; i < len4; i += 2) { data16 = doc_readw(docg3, DOC_IOSPACE_DATA); - *dst16 = data16; - dst16++; + if (dst16) { + *dst16 = data16; + dst16++; + } } if (cdr) { @@ -229,8 +231,10 @@ static void doc_read_data_area(struct docg3 *docg3, void *buf, int len, dst8 = (u8 *)dst16; for (i = 0; i < cdr; i++) { data8 = doc_readb(docg3, DOC_IOSPACE_DATA); - *dst8 = data8; - dst8++; + if (dst8) { + *dst8 = data8; + dst8++; + } } } } @@ -542,96 +546,109 @@ static void calc_block_sector(loff_t from, int *block0, int *block1, int *page, } /** - * doc_read - Read bytes from flash + * doc_read_oob - Read out of band bytes from flash * @mtd: the device * @from: the offset from first block and first page, in bytes, aligned on page * size - * @len: the number of bytes to read (must be a multiple of 4) - * @retlen: the number of bytes actually read - * @buf: the filled in buffer + * @ops: the mtd oob structure * - * Reads flash memory pages. This function does not read the OOB chunk, but only - * the page data. + * Reads flash memory OOB area of pages. * * Returns 0 if read successfull, of -EIO, -EINVAL if an error occured */ -static int doc_read(struct mtd_info *mtd, loff_t from, size_t len, - size_t *retlen, u_char *buf) +static int doc_read_oob(struct mtd_info *mtd, loff_t from, + struct mtd_oob_ops *ops) { struct docg3 *docg3 = mtd->priv; - int block0, block1, page, readlen, ret, ofs = 0; - int syn[DOC_ECC_BCH_SIZE], eccconf1; - u8 oob[DOC_LAYOUT_OOB_SIZE]; + int block0, block1, page, ret, ofs = 0; + u8 *oobbuf = ops->oobbuf; + u8 *buf = ops->datbuf; + size_t len, ooblen, nbdata, nboob; + u8 calc_ecc[DOC_ECC_BCH_SIZE], eccconf1; + + if (buf) + len = ops->len; + else + len = 0; + if (oobbuf) + ooblen = ops->ooblen; + else + ooblen = 0; + + if (oobbuf && ops->mode == MTD_OPS_PLACE_OOB) + oobbuf += ops->ooboffs; + + doc_dbg("doc_read_oob(from=%lld, mode=%d, data=(%p:%zu), oob=(%p:%zu))\n", + from, ops->mode, buf, len, oobbuf, ooblen); + if ((len % DOC_LAYOUT_PAGE_SIZE) || (ooblen % DOC_LAYOUT_OOB_SIZE) || + (from % DOC_LAYOUT_PAGE_SIZE)) + return -EINVAL; ret = -EINVAL; - doc_dbg("doc_read(from=%lld, len=%zu, buf=%p)\n", from, len, buf); - if (from % DOC_LAYOUT_PAGE_SIZE) - goto err; - if (len % 4) - goto err; - calc_block_sector(from, &block0, &block1, &page, &ofs); + calc_block_sector(from + len, &block0, &block1, &page, &ofs); if (block1 > docg3->max_block) goto err; - *retlen = 0; + ops->oobretlen = 0; + ops->retlen = 0; ret = 0; - readlen = min_t(size_t, len, (size_t)DOC_LAYOUT_PAGE_SIZE); - while (!ret && len > 0) { - readlen = min_t(size_t, len, (size_t)DOC_LAYOUT_PAGE_SIZE); + while (!ret && (len > 0 || ooblen > 0)) { + calc_block_sector(from, &block0, &block1, &page, &ofs); + nbdata = min_t(size_t, len, (size_t)DOC_LAYOUT_PAGE_SIZE); + nboob = min_t(size_t, ooblen, (size_t)DOC_LAYOUT_OOB_SIZE); ret = doc_read_page_prepare(docg3, block0, block1, page, ofs); if (ret < 0) goto err; ret = doc_read_page_ecc_init(docg3, DOC_ECC_BCH_COVERED_BYTES); if (ret < 0) goto err_in_read; - ret = doc_read_page_getbytes(docg3, readlen, buf, 1); - if (ret < readlen) + ret = doc_read_page_getbytes(docg3, nbdata, buf, 1); + if (ret < nbdata) goto err_in_read; - ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE, - oob, 0); - if (ret < DOC_LAYOUT_OOB_SIZE) + doc_read_page_getbytes(docg3, DOC_LAYOUT_PAGE_SIZE - nbdata, + NULL, 0); + ret = doc_read_page_getbytes(docg3, nboob, oobbuf, 0); + if (ret < nboob) goto err_in_read; + doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE - nboob, + NULL, 0); - *retlen += readlen; - buf += readlen; - len -= readlen; - - ofs ^= DOC_LAYOUT_PAGE_OOB_SIZE; - if (ofs == 0) - page += 2; - if (page > DOC_ADDR_PAGE_MASK) { - page = 0; - block0 += 2; - block1 += 2; - } - - /* - * There should be a BCH bitstream fixing algorithm here ... - * By now, a page read failure is triggered by BCH error - */ - doc_get_hw_bch_syndroms(docg3, syn); + doc_get_hw_bch_syndroms(docg3, calc_ecc); eccconf1 = doc_register_readb(docg3, DOC_ECCCONF1); - doc_dbg("OOB - INFO: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n", - oob[0], oob[1], oob[2], oob[3], oob[4], - oob[5], oob[6]); - doc_dbg("OOB - HAMMING: %02x\n", oob[7]); - doc_dbg("OOB - BCH_ECC: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n", - oob[8], oob[9], oob[10], oob[11], oob[12], - oob[13], oob[14]); - doc_dbg("OOB - UNUSED: %02x\n", oob[15]); + if (nboob >= DOC_LAYOUT_OOB_SIZE) { + doc_dbg("OOB - INFO: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n", + oobbuf[0], oobbuf[1], oobbuf[2], oobbuf[3], + oobbuf[4], oobbuf[5], oobbuf[6]); + doc_dbg("OOB - HAMMING: %02x\n", oobbuf[7]); + doc_dbg("OOB - BCH_ECC: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n", + oobbuf[8], oobbuf[9], oobbuf[10], oobbuf[11], + oobbuf[12], oobbuf[13], oobbuf[14]); + doc_dbg("OOB - UNUSED: %02x\n", oobbuf[15]); + } doc_dbg("ECC checks: ECCConf1=%x\n", eccconf1); - doc_dbg("ECC BCH syndrom: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n", - syn[0], syn[1], syn[2], syn[3], syn[4], syn[5], syn[6]); + doc_dbg("ECC CALC_ECC: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n", + calc_ecc[0], calc_ecc[1], calc_ecc[2], + calc_ecc[3], calc_ecc[4], calc_ecc[5], + calc_ecc[6]); ret = -EBADMSG; if (block0 >= DOC_LAYOUT_BLOCK_FIRST_DATA) { - if (eccconf1 & DOC_ECCCONF1_BCH_SYNDROM_ERR) + if ((eccconf1 & DOC_ECCCONF1_BCH_SYNDROM_ERR) && + (eccconf1 & DOC_ECCCONF1_PAGE_IS_WRITTEN)) goto err_in_read; if (is_prot_seq_error(docg3)) goto err_in_read; } + doc_read_page_finish(docg3); + ops->retlen += nbdata; + ops->oobretlen += nboob; + buf += nbdata; + oobbuf += nboob; + len -= nbdata; + ooblen -= nboob; + from += DOC_LAYOUT_PAGE_SIZE; } return 0; @@ -642,54 +659,33 @@ err: } /** - * doc_read_oob - Read out of band bytes from flash + * doc_read - Read bytes from flash * @mtd: the device * @from: the offset from first block and first page, in bytes, aligned on page * size - * @ops: the mtd oob structure + * @len: the number of bytes to read (must be a multiple of 4) + * @retlen: the number of bytes actually read + * @buf: the filled in buffer * - * Reads flash memory OOB area of pages. + * Reads flash memory pages. This function does not read the OOB chunk, but only + * the page data. * * Returns 0 if read successfull, of -EIO, -EINVAL if an error occured */ -static int doc_read_oob(struct mtd_info *mtd, loff_t from, - struct mtd_oob_ops *ops) +static int doc_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf) { - struct docg3 *docg3 = mtd->priv; - int block0, block1, page, ofs, ret; - u8 *buf = ops->oobbuf; - size_t len = ops->ooblen; + struct mtd_oob_ops ops; + size_t ret; - doc_dbg("doc_read_oob(from=%lld, buf=%p, len=%zu)\n", from, buf, len); - if (len != DOC_LAYOUT_OOB_SIZE) - return -EINVAL; + memset(&ops, 0, sizeof(ops)); + ops.datbuf = buf; + ops.len = len; + ops.mode = MTD_OPS_AUTO_OOB; - switch (ops->mode) { - case MTD_OPS_PLACE_OOB: - buf += ops->ooboffs; - break; - default: - break; - } - - calc_block_sector(from, &block0, &block1, &page, &ofs); - if (block1 > docg3->max_block) - return -EINVAL; - - ret = doc_read_page_prepare(docg3, block0, block1, page, - ofs + DOC_LAYOUT_PAGE_SIZE); - if (!ret) - ret = doc_read_page_ecc_init(docg3, DOC_LAYOUT_OOB_SIZE); - if (!ret) - ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE, - buf, 1); - doc_read_page_finish(docg3); - - if (ret > 0) - ops->oobretlen = ret; - else - ops->oobretlen = 0; - return (ret > 0) ? 0 : ret; + ret = doc_read_oob(mtd, from, &ops); + *retlen = ops.retlen; + return ret; } static int doc_reload_bbt(struct docg3 *docg3) |