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Date:   Sun, 8 Aug 2021 09:26:43 +0200
From:   Daniel Kestrel <kestrelseventyfour@gmail.com>
Cc:     Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
        Daniel Kestrel <kestrelseventyfour@gmail.com>
Subject: [PATCH v2] mtd: rawnand: xway: No hardcoded ECC engine, use device
 tree setting
Message-ID: <20210808072643.GA5084@ubuntu>
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Some devices use Micron NAND chips, which use on-die ECC. The hardcoded
setting of NAND_ECC_ENGINE_TYPE_SOFT makes them unusable, because the
software ECC on top of the hardware ECC produces errors for every read
and write access, not to mention that booting does not work, because
the boot loader uses the correct ECC when trying to load the kernel
and stops loading on severe ECC errors.
This patch requires the devices that currently work with the hard coded
setting to set the nand-ecc-mode property to soft in their device
tree.

Signed-off-by: Daniel Kestrel <kestrelseventyfour@gmail.com>
Tested-by: Aleksander Jan Bajkowski <olek2@wp.pl> # tested on BT Home Hub 5A
---
 drivers/mtd/nand/raw/xway_nand.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/mtd/nand/raw/xway_nand.c b/drivers/mtd/nand/raw/xway_nand.c
index 26751976e502..0a4b0aa7dd4c 100644
--- a/drivers/mtd/nand/raw/xway_nand.c
+++ b/drivers/mtd/nand/raw/xway_nand.c
@@ -148,8 +148,6 @@ static void xway_write_buf(struct nand_chip *chip, const u_char *buf, int len)
 
 static int xway_attach_chip(struct nand_chip *chip)
 {
-	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
-
 	if (chip->ecc.algo == NAND_ECC_ALGO_UNKNOWN)
 		chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
 
-- 
2.17.1