[MTD] NAND: Combined oob buffer so it's contiguous with data
Ditch the separate oobrbuf and oobwbuf fields from the chip buffers,
and use only a single buffer immediately after the data. This accommodates
NAND controllers such as the OLPC CAFÉ chip, which can't do scatter/gather
DMA so needs the OOB buffer to be contiguous with the data, for both read
and write.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 53c66d5..29090c6 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -971,7 +971,6 @@
page = realpage & chip->pagemask;
col = (int)(from & (mtd->writesize - 1));
- chip->oob_poi = chip->buffers->oobrbuf;
buf = ops->datbuf;
oob = ops->oobbuf;
@@ -1270,8 +1269,6 @@
realpage = (int)(from >> chip->page_shift);
page = realpage & chip->pagemask;
- chip->oob_poi = chip->buffers->oobrbuf;
-
while(1) {
sndcmd = chip->ecc.read_oob(mtd, chip, page, sndcmd);
buf = nand_transfer_oob(chip, buf, ops);
@@ -1625,7 +1622,9 @@
(chip->pagebuf << chip->page_shift) < (to + ops->len))
chip->pagebuf = -1;
- chip->oob_poi = chip->buffers->oobwbuf;
+ /* If we're not given explicit OOB data, let it be 0xFF */
+ if (likely(!oob))
+ memset(chip->oob_poi, 0xff, mtd->oobsize);
while(1) {
int cached = writelen > bytes && page != blockmask;
@@ -1654,9 +1653,6 @@
}
}
- if (unlikely(oob))
- memset(chip->oob_poi, 0xff, mtd->oobsize);
-
ops->retlen = ops->len - writelen;
return ret;
}
@@ -1744,7 +1740,6 @@
if (page == chip->pagebuf)
chip->pagebuf = -1;
- chip->oob_poi = chip->buffers->oobwbuf;
memset(chip->oob_poi, 0xff, mtd->oobsize);
nand_fill_oob(chip, ops->oobbuf, ops);
status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
@@ -2348,8 +2343,8 @@
if (!chip->buffers)
return -ENOMEM;
- /* Preset the internal oob write buffer */
- memset(chip->buffers->oobwbuf, 0xff, mtd->oobsize);
+ /* Set the internal oob buffer location, just after the page data */
+ chip->oob_poi = chip->buffers + mtd->writesize;
/*
* If no default placement scheme is given, select an appropriate one