From: Maxim Levitsky <maximlevitsky@gmail.com>
To: David Woodhouse <dwmw2@infradead.org>
Cc: Artem Bityutskiy <dedekind1@gmail.com>,
linux-mtd <linux-mtd@lists.infradead.org>,
linux-kernel <linux-kernel@vger.kernel.org>,
Alex Dubov <oakad@yahoo.com>, joern <joern@logfs.org>,
Thomas Gleixner <tglx@linutronix.de>,
"stanley.miao" <stanley.miao@windriver.com>,
Vitaly Wool <vitalywool@gmail.com>,
Maxim Levitsky <maximlevitsky@gmail.com>
Subject: [PATCH 10/14] MTD: nand: add ->badblockbits to specify the minimum number of bits in bad block byte to consider the block good
Date: Sat, 13 Feb 2010 15:03:09 +0200 [thread overview]
Message-ID: <1266066193-17625-11-git-send-email-maximlevitsky@gmail.com> (raw)
In-Reply-To: <1266066193-17625-1-git-send-email-maximlevitsky@gmail.com>
This can be used to protect against bitflips in that field, but now mostly
for smartmedia.
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
---
drivers/mtd/nand/nand_base.c | 13 +++++++++----
include/linux/mtd/nand.h | 1 +
2 files changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index c393df3..88750a6 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -335,14 +335,18 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
bad = cpu_to_le16(chip->read_word(mtd));
if (chip->badblockpos & 0x1)
bad >>= 8;
- if ((bad & 0xFF) != 0xff)
- res = 1;
+ else
+ bad &= 0xFF;
} else {
chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos, page);
- if (chip->read_byte(mtd) != 0xff)
- res = 1;
+ bad = chip->read_byte(mtd);
}
+ if (likely(chip->badblockbits == 8))
+ res = bad != 0xFF;
+ else
+ res = hweight8(bad) < chip->badblockbits;
+
if (getchip)
nand_release_device(mtd);
@@ -2710,6 +2714,7 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
/* Set the bad block position */
chip->badblockpos = mtd->writesize > 512 ?
NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS;
+ chip->badblockbits = 8;
/* Get chip options, preserve non chip based options */
chip->options &= ~NAND_CHIPOPTIONS_MSK;
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index ccab9df..27d998e 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -391,6 +391,7 @@ struct nand_chip {
int subpagesize;
uint8_t cellinfo;
int badblockpos;
+ int badblockbits;
flstate_t state;
--
1.6.3.3
next prev parent reply other threads:[~2010-02-13 13:03 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-13 13:02 [PATCH 0/14 V8] Work to enable SmartMedia/xD support in mtd Maxim Levitsky
2010-02-13 13:03 ` [PATCH 01/14] MTD: create unlocked versions of {get,put}_mtd_device Use these only if you know that you already hold mtd_table_mutex Maxim Levitsky
2010-02-13 13:03 ` [PATCH 02/14] blktrans: remove mtd_blkcore_priv and switch to per device queue and thread Maxim Levitsky
2010-02-13 13:03 ` [PATCH 03/14] blktrans: Hotplug fixes Maxim Levitsky
2010-02-13 13:03 ` [PATCH 04/14] MTD: call the remove notifiers before assuming it is in use Maxim Levitsky
2010-02-13 13:03 ` [PATCH 05/14] blktrans: allow FTL drivers to export sysfs attributes Maxim Levitsky
2010-02-13 13:03 ` [PATCH 06/14] MTD: nand: make suspend work if device is accessed by kernel threads Maxim Levitsky
2010-02-13 13:03 ` [PATCH 07/14] MTD: nand: make MTD_OOB_PLACE work correctly Maxim Levitsky
2010-02-13 13:03 ` [PATCH 08/14] MTD: nand: cleanup the nand_do_write_ops Maxim Levitsky
2010-02-13 13:03 ` [PATCH 09/14] MTD: nand: make reads using MTD_OOB_RAW affect only ECC validation Maxim Levitsky
2010-02-13 13:03 ` Maxim Levitsky [this message]
2010-02-13 13:03 ` [PATCH 11/14] MTD: common module for smartmedia/xD support Maxim Levitsky
2010-02-13 13:03 ` [PATCH 12/14] MTD: add few workarounds to nand system for SmartMedia/xD chips Maxim Levitsky
2010-02-13 13:03 ` [PATCH 13/14] MTD: Add nand driver for ricoh xD/SmartMedia reader Maxim Levitsky
2010-02-13 13:03 ` [PATCH 14/14] MTD: Add new SmartMedia/xD FTL Maxim Levitsky
-- strict thread matches above, loose matches on Subject: below --
2010-02-17 21:49 [PATCH 0/14 V9] Work to enable SmartMedia/xD support in mtd Maxim Levitsky
2010-02-17 21:49 ` [PATCH 10/14] MTD: nand: add ->badblockbits to specify the minimum number of bits in bad block byte to consider the block good Maxim Levitsky
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=1266066193-17625-11-git-send-email-maximlevitsky@gmail.com \
--to=maximlevitsky@gmail.com \
--cc=dedekind1@gmail.com \
--cc=dwmw2@infradead.org \
--cc=joern@logfs.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mtd@lists.infradead.org \
--cc=oakad@yahoo.com \
--cc=stanley.miao@windriver.com \
--cc=tglx@linutronix.de \
--cc=vitalywool@gmail.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;
as well as URLs for NNTP newsgroup(s).