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 --- drivers/mtd/nand/raw/nand_base.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 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; - return; - } + end_page = DIV_ROUND_UP(col + readlen, mtd->writesize); + end_col = (col + readlen) % mtd->writesize;
- 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); + page++; + + if (end_col && end_page) + end_page--; + + if (page + 1 > end_page) + return; + + chip->cont_read.first_page = page; + chip->cont_read.last_page = end_page; + chip->cont_read.ongoing = true; + rawnand_cap_cont_reads(chip); }