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>
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 @@
/**
* 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 @@
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 @@
dst8 = (u8 *)dst16;
for (i = 0; i < cdr; i++) {
data8 = doc_readb(docg3, DOC_IOSPACE_DATA);
- *dst8 = data8;
- dst8++;
+ if (dst8) {
+ *dst8 = data8;
+ dst8++;
+ }
}
}
}
@@ -542,6 +546,119 @@
}
/**
+ * 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
+ * @ops: the mtd oob structure
+ *
+ * Reads flash memory OOB area of pages.
+ *
+ * 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)
+{
+ struct docg3 *docg3 = mtd->priv;
+ 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;
+ calc_block_sector(from + len, &block0, &block1, &page, &ofs);
+ if (block1 > docg3->max_block)
+ goto err;
+
+ ops->oobretlen = 0;
+ ops->retlen = 0;
+ ret = 0;
+ 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, nbdata, buf, 1);
+ if (ret < nbdata)
+ goto err_in_read;
+ 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);
+
+ doc_get_hw_bch_syndroms(docg3, calc_ecc);
+ eccconf1 = doc_register_readb(docg3, DOC_ECCCONF1);
+
+ 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 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) &&
+ (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;
+err_in_read:
+ doc_read_page_finish(docg3);
+err:
+ return ret;
+}
+
+/**
* doc_read - Read bytes from flash
* @mtd: the device
* @from: the offset from first block and first page, in bytes, aligned on page
@@ -558,140 +675,19 @@
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, readlen, ret, ofs = 0;
- int syn[DOC_ECC_BCH_SIZE], eccconf1;
- u8 oob[DOC_LAYOUT_OOB_SIZE];
+ struct mtd_oob_ops ops;
+ size_t ret;
- 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);
- if (block1 > docg3->max_block)
- goto err;
+ memset(&ops, 0, sizeof(ops));
+ ops.datbuf = buf;
+ ops.len = len;
+ ops.mode = MTD_OPS_AUTO_OOB;
- *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);
- 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)
- goto err_in_read;
- ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE,
- oob, 0);
- if (ret < DOC_LAYOUT_OOB_SIZE)
- goto err_in_read;
-
- *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);
- 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]);
- 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]);
-
- ret = -EBADMSG;
- if (block0 >= DOC_LAYOUT_BLOCK_FIRST_DATA) {
- if (eccconf1 & DOC_ECCCONF1_BCH_SYNDROM_ERR)
- goto err_in_read;
- if (is_prot_seq_error(docg3))
- goto err_in_read;
- }
- doc_read_page_finish(docg3);
- }
-
- return 0;
-err_in_read:
- doc_read_page_finish(docg3);
-err:
+ ret = doc_read_oob(mtd, from, &ops);
+ *retlen = ops.retlen;
return ret;
}
-/**
- * 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
- * @ops: the mtd oob structure
- *
- * Reads flash memory OOB area of pages.
- *
- * 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)
-{
- struct docg3 *docg3 = mtd->priv;
- int block0, block1, page, ofs, ret;
- u8 *buf = ops->oobbuf;
- size_t len = ops->ooblen;
-
- doc_dbg("doc_read_oob(from=%lld, buf=%p, len=%zu)\n", from, buf, len);
- if (len != DOC_LAYOUT_OOB_SIZE)
- return -EINVAL;
-
- 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;
-}
-
static int doc_reload_bbt(struct docg3 *docg3)
{
int block = DOC_LAYOUT_BLOCK_BBT;