Linux-mtd Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
To: Brian Norris <computersforpeace@gmail.com>
Cc: linux-mtd@lists.infradead.org, Pekon Gupta <pekon@ti.com>
Subject: Re: [PATCH] mtd: nand_bbt: kill NAND_BBT_SCANALLPAGES
Date: Thu, 31 Oct 2013 12:32:43 -0300	[thread overview]
Message-ID: <20131031153242.GB1092@localhost> (raw)
In-Reply-To: <20131031152245.GB4700@norris.computersforpeace.net>

On Thu, Oct 31, 2013 at 11:22:45AM -0400, Brian Norris wrote:
> On Thu, Oct 31, 2013 at 07:20:39AM -0300, Ezequiel Garcia wrote:
> > On Wed, Oct 30, 2013 at 10:29:35PM -0400, Brian Norris wrote:
> > > Now that the last user of NAND_BBT_SCANALLPAGES has been removed, let's
> > > kill this peculiar BBT feature flag.
> > > 
> > 
> > I must admit I also find this option a bit puzzling.
> > 
> > However, I'm wondering what happens if a manufacturer specifies
> > the bad block mark is in some page at the middle of a block.
> > 
> > AFAIK, some of them do exactly that, and I've always thought
> > this option was the solution for such cases.
> 
> Well, it's not really a *good* solution for a marker in the middle of
> the page, as it's both inaccurate and heavily inefficient.

Granted.

> I've never heard of such a device. (There is a rare one or two that uses
> the 2nd-to-last or 3rd-to-last page.) Do you have any examples?
> 

Not at hand.

> > So, is this really no longer needed?
> 
> I think it just adds unnecessary complexity to nand_bbt.c. Generally,
> the fewer (unused) options the better. Also, this helps clear the way
> for some nand_base/nand_bbt simplification that I have planned.
> 
> Additionally, I think its only users were either accidental (in the case
> of omap2.c) or lazy (which didn't want to figure out the correct pages
> to scan for bad block markers). And now there are no users.
> 

Ok, agreed. But do we have any mechanism to scan a *particular*
page?

-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com

  reply	other threads:[~2013-10-31 15:33 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-10-31  2:29 [PATCH] mtd: nand_bbt: kill NAND_BBT_SCANALLPAGES Brian Norris
2013-10-31 10:20 ` Ezequiel Garcia
2013-10-31 15:22   ` Brian Norris
2013-10-31 15:32     ` Ezequiel Garcia [this message]
2013-10-31 17:52       ` Brian Norris
2013-10-31 19:04 ` Ezequiel Garcia
2013-11-01  9:01   ` Artem Bityutskiy
2013-11-01 18:33     ` Brian Norris

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=20131031153242.GB1092@localhost \
    --to=ezequiel.garcia@free-electrons.com \
    --cc=computersforpeace@gmail.com \
    --cc=linux-mtd@lists.infradead.org \
    --cc=pekon@ti.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox