From: "Piotr Zięcik" <kosmo@semihalf.com>
To: John Rigby <jcrigby@gmail.com>
Cc: Grant Likely <grant.likely@secretlab.ca>,
linuxppc-dev@ozlabs.org, linux-mtd@lists.infradead.org
Subject: Re: [PATCH 06/12] mpc5121: Added NAND Flash Controller driver.
Date: Wed, 13 May 2009 10:41:45 +0200 [thread overview]
Message-ID: <200905131041.45944.kosmo@semihalf.com> (raw)
In-Reply-To: <4b73d43f0905072030n1b014dafmea840387ab0f3a6d@mail.gmail.com>
Friday 08 May 2009 05:30:15 John Rigby napisał(a):
> Did you choose to not support hardware ECC so you could use the spare area?
> The original driver only supported hardware ECC but unfortuneatly the
> hardware ECC includes the spare area so the spare area cannot be written
> separately.
In short yes. There are fundamental problems which you described. Flash
filesystems expect that ECC is calculated from main area only and writes to
spare area not change it. MPC5121 NAND flash controller calculates ECC from
both areas except few bytes holding ECC. This makes flash filesystems
unusable when we turn on hardware ECC.
This could be fixed by disabling spare area usage in flash filesystems but
this probably requires changes in the MTD/filesystem infrastructure.
--
Best Regards.
Piotr Zięcik
WARNING: multiple messages have this Message-ID (diff)
From: "Piotr Zięcik" <kosmo@semihalf.com>
To: John Rigby <jcrigby@gmail.com>
Cc: linuxppc-dev@ozlabs.org, linux-mtd@lists.infradead.org,
Wolfgang Denk <wd@denx.de>
Subject: Re: [PATCH 06/12] mpc5121: Added NAND Flash Controller driver.
Date: Wed, 13 May 2009 10:41:45 +0200 [thread overview]
Message-ID: <200905131041.45944.kosmo@semihalf.com> (raw)
In-Reply-To: <4b73d43f0905072030n1b014dafmea840387ab0f3a6d@mail.gmail.com>
=46riday 08 May 2009 05:30:15 John Rigby napisa=B3(a):
> Did you choose to not support hardware ECC so you could use the spare are=
a?
> The original driver only supported hardware ECC but unfortuneatly the
> hardware ECC includes the spare area so the spare area cannot be written
> separately.
In short yes. There are fundamental problems which you described. Flash=20
filesystems expect that ECC is calculated from main area only and writes to=
=20
spare area not change it. MPC5121 NAND flash controller calculates ECC from=
=20
both areas except few bytes holding ECC. This makes flash filesystems=20
unusable when we turn on hardware ECC.
This could be fixed by disabling spare area usage in flash filesystems but
this probably requires changes in the MTD/filesystem infrastructure.
=2D-=20
Best Regards.
Piotr Zi=EAcik
next prev parent reply other threads:[~2009-05-13 8:42 UTC|newest]
Thread overview: 128+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-06 20:15 [PATCH 00/16] Add support for MPC512x Wolfgang Denk
2009-05-06 20:15 ` [PATCH 01/12] fs_enet: Use defines to set driver tunables Wolfgang Denk
2009-05-06 20:15 ` Wolfgang Denk
2009-05-06 20:35 ` Grant Likely
2009-05-06 20:35 ` Grant Likely
2009-05-06 22:02 ` Wolfgang Denk
2009-05-06 22:41 ` Grant Likely
2009-05-06 22:41 ` Grant Likely
2009-05-06 20:15 ` [PATCH 02/12] fs_enet: Add MPC5121 FEC support Wolfgang Denk
2009-05-06 20:15 ` Wolfgang Denk
2009-05-06 20:33 ` Grant Likely
2009-05-06 20:33 ` Grant Likely
2009-05-06 21:08 ` Scott Wood
2009-05-06 21:08 ` Scott Wood
2009-05-06 22:01 ` Wolfgang Denk
2009-05-06 22:01 ` Wolfgang Denk
2009-05-06 22:29 ` Grant Likely
2009-05-06 22:29 ` Grant Likely
2009-05-06 22:41 ` Wolfgang Denk
2009-05-06 22:41 ` Wolfgang Denk
2009-05-07 14:09 ` Grant Likely
2009-05-07 14:09 ` Grant Likely
2009-05-08 2:02 ` John Rigby
2009-05-08 2:02 ` John Rigby
2009-05-08 7:52 ` David Miller
2009-05-08 7:52 ` David Miller
2009-05-11 6:56 ` David Jander
2009-05-07 8:14 ` David Jander
2009-05-07 13:05 ` Kumar Gala
2009-05-06 20:40 ` David Miller
2009-05-06 20:40 ` David Miller
2009-05-06 22:06 ` Wolfgang Denk
2009-05-06 20:41 ` Scott Wood
2009-05-06 20:41 ` Scott Wood
2009-05-06 22:09 ` Wolfgang Denk
2009-05-06 22:39 ` Grant Likely
2009-05-06 22:39 ` Grant Likely
2009-05-14 12:38 ` Piotr Zięcik
2009-05-14 12:38 ` Piotr Zięcik
2009-05-14 14:00 ` Grant Likely
2009-05-14 14:00 ` Grant Likely
2009-05-18 22:17 ` Benjamin Herrenschmidt
2009-05-19 11:26 ` Piotr Zięcik
2009-05-19 11:26 ` Piotr Zięcik
2009-05-19 21:56 ` Benjamin Herrenschmidt
2009-05-19 21:56 ` Benjamin Herrenschmidt
2009-05-21 8:34 ` Piotr Zięcik
2009-05-21 8:34 ` Piotr Zięcik
2009-05-21 15:36 ` Grant Likely
2009-05-21 15:36 ` Grant Likely
2009-05-06 20:15 ` [PATCH 03/12] fs_enet: Add FEC TX Alignment workaround for MPC5121 Wolfgang Denk
2009-05-06 20:15 ` Wolfgang Denk
2009-05-06 20:37 ` Grant Likely
2009-05-06 20:37 ` Grant Likely
2009-05-06 22:12 ` Wolfgang Denk
2009-05-06 22:42 ` Grant Likely
2009-05-06 22:42 ` Grant Likely
2009-05-08 2:36 ` John Rigby
2009-05-08 2:36 ` John Rigby
2009-05-06 20:15 ` [PATCH 04/12] mpc5121: Added reset module registers representation Wolfgang Denk
2009-05-06 20:29 ` Scott Wood
2009-05-06 21:57 ` Wolfgang Denk
2009-05-06 20:39 ` Grant Likely
2009-05-06 22:14 ` Wolfgang Denk
2009-05-06 20:15 ` [PATCH 05/12] mpc5121ads: Added Reset Module node to DTS Wolfgang Denk
2009-05-06 20:40 ` Grant Likely
2009-05-06 22:16 ` Wolfgang Denk
2009-05-06 22:46 ` Grant Likely
2009-05-06 20:15 ` [PATCH 06/12] mpc5121: Added NAND Flash Controller driver Wolfgang Denk
2009-05-06 20:15 ` Wolfgang Denk
2009-05-06 20:59 ` Grant Likely
2009-05-06 20:59 ` Grant Likely
2009-05-08 2:22 ` John Rigby
2009-05-08 3:07 ` Grant Likely
2009-05-08 3:07 ` Grant Likely
2009-05-07 8:08 ` David Jander
2009-05-07 8:08 ` David Jander
2009-05-08 3:30 ` John Rigby
2009-05-13 8:41 ` Piotr Zięcik [this message]
2009-05-13 8:41 ` Piotr Zięcik
2009-05-06 20:15 ` [PATCH 07/12] mpc5121ads: Clean up and fix NAND description in mpc5121ads DTS Wolfgang Denk
2009-05-06 21:00 ` Grant Likely
[not found] ` <1241640919-4650-1-git-send-email-wd-ynQEQJNshbs@public.gmane.org>
2009-05-06 20:15 ` [PATCH 08/12] mpc5121: Added I2C support Wolfgang Denk
2009-05-06 20:15 ` Wolfgang Denk
[not found] ` <1241640919-4650-9-git-send-email-wd-ynQEQJNshbs@public.gmane.org>
2009-05-06 21:01 ` Grant Likely
2009-05-06 21:01 ` Grant Likely
[not found] ` <fa686aa40905061401k319313c5q89fd3e245c30808f-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2009-05-06 22:19 ` Wolfgang Denk
2009-05-06 22:19 ` Wolfgang Denk
2009-05-06 22:51 ` Grant Likely
[not found] ` <fa686aa40905061551l8cf5940sf4d4cbf34331cf9a-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2009-05-07 2:41 ` Grant Likely
2009-05-07 2:41 ` Grant Likely
[not found] ` <fa686aa40905061941p6fd4b03dt1097cf4d16bdd665-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2009-05-07 6:36 ` Wolfgang Grandegger
2009-05-07 6:36 ` Wolfgang Grandegger
2009-05-18 13:57 ` Piotr Zięcik
2009-05-18 13:57 ` Piotr Zięcik
2009-05-18 14:11 ` Grant Likely
2009-05-18 14:11 ` Grant Likely
[not found] ` <200905181557.11766.kosmo-nYOzD4b6Jr9Wk0Htik3J/w@public.gmane.org>
2009-05-18 14:29 ` Wolfgang Grandegger
2009-05-18 14:29 ` Wolfgang Grandegger
[not found] ` <4A1170B0.5080203-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org>
2009-05-19 7:47 ` Piotr Zięcik
2009-05-19 7:47 ` Piotr Zięcik
2009-05-19 8:10 ` Wolfgang Grandegger
2009-05-08 2:12 ` John Rigby
2009-05-08 2:12 ` John Rigby
2009-05-08 3:01 ` Grant Likely
2009-05-08 3:01 ` Grant Likely
2009-05-06 20:15 ` [PATCH 09/12] mpc5121ads: Added I2C RTC node to mpc5121ads DTS Wolfgang Denk
2009-05-06 21:02 ` Grant Likely
2009-05-07 6:45 ` Wolfgang Grandegger
2009-05-06 20:15 ` [PATCH 10/12] mpc5121: Add MPC5121 Real time clock driver Wolfgang Denk
2009-05-06 21:03 ` Grant Likely
2009-05-06 21:06 ` Wolfram Sang
2009-05-06 22:40 ` Grant Likely
2009-05-08 2:41 ` [rtc-linux] " John Rigby
2009-05-08 15:53 ` Grant Likely
2009-05-08 16:09 ` Alessandro Zummo
2009-05-08 19:18 ` Wolfgang Denk
2009-05-08 16:10 ` Alessandro Zummo
2009-05-06 20:15 ` [PATCH 11/12] mpc5121: Added MPC512x DMA driver Wolfgang Denk
2009-05-06 21:07 ` Grant Likely
2009-05-08 2:49 ` John Rigby
2009-05-19 1:37 ` Hongjun Chen
2009-05-19 8:03 ` Piotr Zięcik
2009-05-20 0:39 ` Hongjun Chen
2009-05-06 20:15 ` [PATCH 12/12] mpc5121: Added default config for MPC5121 Wolfgang Denk
2009-05-06 21:08 ` Grant Likely
2009-05-06 22:23 ` Wolfgang Denk
2009-05-06 22:48 ` Grant Likely
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=200905131041.45944.kosmo@semihalf.com \
--to=kosmo@semihalf.com \
--cc=grant.likely@secretlab.ca \
--cc=jcrigby@gmail.com \
--cc=linux-mtd@lists.infradead.org \
--cc=linuxppc-dev@ozlabs.org \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.