From mboxrd@z Thu Jan 1 00:00:00 1970 From: Miquel Raynal Date: Mon, 19 Apr 2021 09:32:44 +0200 Subject: gpmi-nand ecc In-Reply-To: References: Message-ID: <20210419093244.1f27cb48@xps13> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Sean, + u-boot ML Sean Nyekjaer wrote on Wed, 14 Apr 2021 15:13:39 +0200: > Hi, > > I have two boards with a iMX6ULL SoC one attached to a Micron NAND flash (MT29F4G08ABAFAWP) and one a Toshiba (TC58BVG2S0HTAI0). > > After updating the boards from u-boot 2018.07 -> 2020.01, the Micron fitted boards is having ECC problems(in u-boot). > U-boot 2018.07 selects ecc_strength to 18. > U-boot 2020.01 selects ecc_strength to 8, but if I hardcode u-boot to run the mxs_nand_legacy_calc_ecc_layout() it selects 18 bits. > > The Toshiba boards always selects 8 bit ecc_strength so they have no issues. > > The kernel driver (gpmi-nand.c) seems to also use the legacy method (Resulting 18 bits in ecc strength for the Micron NAND). > In common_nfc_set_geometry(): Both chip->ecc.strength and chip->ecc.size are 0. > > I would expect ecc.strength to be set to 8, earlier but cannot find the spot where it should be set. > Is the gpmi-nand driver missing a call to nand_ecc_choose_conf()? > Maybe we need a legacy option for the kernel like u-boot. > > We have +10K boards deployed so it's not so easy to switch from 18 -> 8 bits. > I can explicit fix this in U-boot by forcing the legacy mode via a dt flag, but the gut feeling says this will come back to haunt us :) > > /Sean I honestly don't know about such issue on U-Boot side, maybe you can try to be more specific on what commit broke the logic for you as there are not so many of them between the two versions: $ git l v2018.07..v2020.01 -- drivers/mtd/nand/raw/mxs_nand.c 1eb69ae4985 common: Move ARM cache operations out of common.h 9ab5f221a5e nand: mxs_nand: add API for switching different BCH layouts 1d43e24b946 i.MX6: nand: add nandbcb command for imx 1001502545f CONFIG_SPL_SYS_[DI]CACHE_OFF: add 04568bd0b6d MTD: nand: mxs_nand: Allow driver to auto setup ECC in SPL 5645df9e00a MTD: NAND: mxs_nand_init_dma: Make mxs_nand_init_dma static 5ae585ba3a8 MTD: mxs_nand: Fix BCH read timeout error on boards requiring ECC a430fa06a4a mtd: move NAND files into a raw/ subdirectory Good luck with your debugging, Miqu?l