From d26f0b293b437becf572983c856fb5d2223c6bf3 Mon Sep 17 00:00:00 2001 From: Miquel Raynal Date: Sun, 26 Jul 2026 08:38:44 -0400 Subject: [PATCH] mtd: rawnand: Pause continuous reads at block boundaries [ Upstream commit 8e4531667d718e2e9b193928cf9b2497fa0d01ef ] Some chips do not support sequential cached reads past block boundaries, like Winbond. In practice when using UBI, this should very rarely happen, but let's make sure it never happens. Cc: stable@vger.kernel.org Fixes: 003fe4b9545b ("mtd: rawnand: Support for sequential cache reads") Signed-off-by: Miquel Raynal Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/mtd/nand/raw/nand_base.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index 11b0fb4bde96..b2f56d89bfd3 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -1212,32 +1212,32 @@ static int nand_lp_exec_read_page_op(struct nand_chip *chip, unsigned int page, return nand_exec_op(chip, &op); } -static unsigned int rawnand_last_page_of_lun(unsigned int pages_per_lun, unsigned int lun) +static unsigned int rawnand_last_page_of_block(unsigned int ppb, unsigned int block) { - /* lun is expected to be very small */ - return (lun * pages_per_lun) + pages_per_lun - 1; + /* block is expected to be very small */ + return (block * ppb) + ppb - 1; } static void rawnand_cap_cont_reads(struct nand_chip *chip) { struct nand_memory_organization *memorg; - unsigned int ppl, first_lun, last_lun; + unsigned int ppb, first_block, last_block; memorg = nanddev_get_memorg(&chip->base); - ppl = memorg->pages_per_eraseblock * memorg->eraseblocks_per_lun; - first_lun = chip->cont_read.first_page / ppl; - last_lun = chip->cont_read.last_page / ppl; + ppb = memorg->pages_per_eraseblock; + first_block = chip->cont_read.first_page / ppb; + last_block = chip->cont_read.last_page / ppb; - /* Prevent sequential cache reads across LUN boundaries */ - if (first_lun != last_lun) - chip->cont_read.pause_page = rawnand_last_page_of_lun(ppl, first_lun); + /* Prevent sequential cache reads across block boundaries */ + if (first_block != last_block) + chip->cont_read.pause_page = rawnand_last_page_of_block(ppb, first_block); else chip->cont_read.pause_page = chip->cont_read.last_page; if (chip->cont_read.first_page == chip->cont_read.pause_page) { chip->cont_read.first_page++; chip->cont_read.pause_page = min(chip->cont_read.last_page, - rawnand_last_page_of_lun(ppl, first_lun + 1)); + rawnand_last_page_of_block(ppb, first_block + 1)); } if (chip->cont_read.first_page >= chip->cont_read.last_page)