LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Jan Hoffmann <jan@3e8.eu>
To: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Daniel Kestrel <kestrelseventyfour@gmail.com>,
	Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] mtd: rawnand: xway: No hardcoded ECC engine, use device tree setting
Date: Sat, 18 Sep 2021 23:26:48 +0200	[thread overview]
Message-ID: <14eb0cb7-b0af-87bf-b9a5-3e35eeb43f54@3e8.eu> (raw)
In-Reply-To: <20210917213246.319e60cb@xps13>

Hi Miquèl,

> Yes this was my understanding, that only software ECC engine was
> supported. The mainline driver shows absolutely no signs of hardware
> ECC engine support.
> 
> Perhaps however you mean that on-die ECC engine are not supported
> anymore because of the engine_type being set in attach_chip()?

Yes, this is exactly the issue.

> If yes then indeed there is something to do, perhaps checking if an
> engine has been already set is enough? You can try something like:
> 
> if (engine_type == unknown)
> 	engine_type = soft;

Checking for NAND_ECC_ENGINE_TYPE_INVALID doesn't work, as the engine
type is already set to NAND_ECC_ENGINE_TYPE_ON_HOST by rawnand_dt_init.
The code there seems to expect that chip->ecc.engine_type contains the
default value, which is no longer the case after commit 525914b5bd8
("mtd: rawnand: xway: Move the ECC initialization to ->attach_chip()").

The following in attach_chip works:

if (chip->ecc.engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST)
	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;

However, this will also silently use the software ECC engine if anyone
actually configures the on-host hardware ECC engine in the device tree
(which is of course unsupported for xway).

Thanks,
Jan

  reply	other threads:[~2021-09-18 21:35 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-08  7:26 Daniel Kestrel
2021-08-16  7:31 ` Miquel Raynal
2021-08-19  7:21   ` Kestrel seventyfour
2021-08-19  8:03     ` Miquel Raynal
2021-08-23 11:19       ` Kestrel seventyfour
2021-08-23 15:24         ` Miquel Raynal
2021-08-24  7:15           ` Kestrel seventyfour
2021-08-24 17:22             ` Miquel Raynal
2021-08-25  8:47               ` Kestrel seventyfour
2021-08-25  8:51                 ` Miquel Raynal
2021-08-25 14:07                   ` Kestrel seventyfour
2021-08-25 15:31                     ` Miquel Raynal
2021-08-26  5:27                       ` Kestrel seventyfour
2021-09-16 19:38 ` Jan Hoffmann
2021-09-17 17:01   ` Miquel Raynal
2021-09-17 17:45     ` Jan Hoffmann
2021-09-17 19:32       ` Miquel Raynal
2021-09-18 21:26         ` Jan Hoffmann [this message]
2021-09-27 16:31           ` Miquel Raynal
2021-09-27 20:32             ` Jan Hoffmann
2021-09-28  8:49               ` Miquel Raynal

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=14eb0cb7-b0af-87bf-b9a5-3e35eeb43f54@3e8.eu \
    --to=jan@3e8.eu \
    --cc=kestrelseventyfour@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mtd@lists.infradead.org \
    --cc=miquel.raynal@bootlin.com \
    --cc=richard@nod.at \
    --cc=vigneshr@ti.com \
    --subject='Re: [PATCH v2] mtd: rawnand: xway: No hardcoded ECC engine, use device tree setting' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).