diff options
author | Miquel Raynal <miquel.raynal@bootlin.com> | 2023-12-15 13:32:08 +0100 |
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committer | Miquel Raynal <miquel.raynal@bootlin.com> | 2023-12-22 12:39:30 +0100 |
commit | 828f6df1bcba7f64729166efc7086ea657070445 (patch) | |
tree | f9498163d0b42099f447fa1064cfbf0fcff1ba8b /drivers/mtd | |
parent | a62c4597953fe54c6af04166a5e2872efd0e1490 (diff) | |
download | lwn-828f6df1bcba7f64729166efc7086ea657070445.tar.gz lwn-828f6df1bcba7f64729166efc7086ea657070445.zip |
mtd: rawnand: Clarify conditions to enable continuous reads
The current logic is probably fine but is a bit convoluted. Plus, we
don't want partial pages to be part of the sequential operation just in
case the core would optimize the page read with a subpage read (which
would break the sequence). This may happen on the first and last page
only, so if the start offset or the end offset is not aligned with a
page boundary, better avoid them to prevent any risk.
Cc: stable@vger.kernel.org
Fixes: 003fe4b9545b ("mtd: rawnand: Support for sequential cache reads")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Tested-by: Martin Hundebøll <martin@geanix.com>
Link: https://lore.kernel.org/linux-mtd/20231215123208.516590-5-miquel.raynal@bootlin.com
Diffstat (limited to 'drivers/mtd')
-rw-r--r-- | drivers/mtd/nand/raw/nand_base.c | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index 139fdf3e58c0..bbdcfbe643f3 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -3460,21 +3460,29 @@ static void rawnand_enable_cont_reads(struct nand_chip *chip, unsigned int page, u32 readlen, int col) { struct mtd_info *mtd = nand_to_mtd(chip); + unsigned int end_page, end_col; + + chip->cont_read.ongoing = false; if (!chip->controller->supported_op.cont_read) return; - if ((col && col + readlen < (3 * mtd->writesize)) || - (!col && readlen < (2 * mtd->writesize))) { - chip->cont_read.ongoing = false; + end_page = DIV_ROUND_UP(col + readlen, mtd->writesize); + end_col = (col + readlen) % mtd->writesize; + + if (col) + page++; + + if (end_col && end_page) + end_page--; + + if (page + 1 > end_page) return; - } - chip->cont_read.ongoing = true; chip->cont_read.first_page = page; - if (col) - chip->cont_read.first_page++; - chip->cont_read.last_page = page + ((readlen >> chip->page_shift) & chip->pagemask); + chip->cont_read.last_page = end_page; + chip->cont_read.ongoing = true; + rawnand_cap_cont_reads(chip); } |