mtd: rawnand: brcmnand: correctly verify erased pages

The current code checks that the whole OOB area is erased.
This is a problem when JFFS2 cleanmarkers are added to the OOB, since it will
fail due to the usable OOB bytes not being 0xff.
Correct this by only checking that data and ECC bytes aren't 0xff.

Fixes: 02b88eea9f9c ("mtd: brcmnand: Add check for erased page bitflips")
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200512082451.771212-1-noltari@gmail.com
[Ported to U-Boot from the Linux kernel]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: William Zhang <william.zhang@broadcom.com>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index a934373a29928c7361bd67a8fa4ad6896ca9817e..5d3fb460d89af0cba34e90f1e74fcc5433770e80 100644 (file)
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -1777,11 +1777,12 @@ static int brcmnand_read_by_pio(struct mtd_info *mtd, struct nand_chip *chip,
 static int brcmstb_nand_verify_erased_page(struct mtd_info *mtd,
                  struct nand_chip *chip, void *buf, u64 addr)
 {
-       int i, sas;
-       void *oob = chip->oob_poi;
+       struct mtd_oob_region ecc;
+       int i;
        int bitflips = 0;
        int page = addr >> chip->page_shift;
        int ret;
+       void *ecc_bytes;
        void *ecc_chunk;
 
        if (!buf) {
@@ -1794,18 +1795,20 @@ static int brcmstb_nand_verify_erased_page(struct mtd_info *mtd,
                chip->pagebuf = -1;
        }
 
-       sas = mtd->oobsize / chip->ecc.steps;
-
        /* read without ecc for verification */
        ret = chip->ecc.read_page_raw(mtd, chip, buf, true, page);
        if (ret)
                return ret;
 
-       for (i = 0; i < chip->ecc.steps; i++, oob += sas) {
+       for (i = 0; i < chip->ecc.steps; i++) {
                ecc_chunk = buf + chip->ecc.size * i;
-               ret = nand_check_erased_ecc_chunk(ecc_chunk,
-                                                 chip->ecc.size,
-                                                 oob, sas, NULL, 0,
+
+               mtd_ooblayout_ecc(mtd, i, &ecc);
+               ecc_bytes = chip->oob_poi + ecc.offset;
+
+               ret = nand_check_erased_ecc_chunk(ecc_chunk, chip->ecc.size,
+                                                 ecc_bytes, ecc.length,
+                                                 NULL, 0,
                                                  chip->ecc.strength);
                if (ret < 0)
                        return ret;