From 3287f6d3858faee768a7c47515bd21914ad591a2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Beno=C3=AEt=20Th=C3=A9baudeau?= Date: Fri, 16 Nov 2012 20:20:54 +0100 Subject: nand: Add torture feature MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch adds a NAND Flash torture feature, which is useful as a block stress test to determine if a block is still good and reliable (or should be marked as bad), e.g. after a write error. This code is ported from mtd-utils' lib/libmtd.c. Signed-off-by: Benoît Thébaudeau Cc: Scott Wood [scottwood@freescale.com: removed unnec. ifdef and unwrapped error strings] Signed-off-by: Scott Wood --- doc/README.nand | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'doc/README.nand') diff --git a/doc/README.nand b/doc/README.nand index c130189587..a1a511c533 100644 --- a/doc/README.nand +++ b/doc/README.nand @@ -108,6 +108,9 @@ Configuration Options: CONFIG_CMD_NAND Enables NAND support and commmands. + CONFIG_CMD_NAND_TORTURE + Enables the torture command (see description of this command below). + CONFIG_MTD_NAND_ECC_JFFS2 Define this if you want the Error Correction Code information in the out-of-band data to be formatted to match the JFFS2 file system. @@ -213,6 +216,24 @@ Miscellaneous and testing commands: DANGEROUS!!! Factory set bad blocks will be lost. Use only to remove artificial bad blocks created with the "markbad" command. + "torture offset" + Torture block to determine if it is still reliable. + Enabled by the CONFIG_CMD_NAND_TORTURE configuration option. + This command returns 0 if the block is still reliable, else 1. + If the block is detected as unreliable, it is up to the user to decide to + mark this block as bad. + The analyzed block is put through 3 erase / write cycles (or less if the block + is detected as unreliable earlier). + This command can be used in scripts, e.g. together with the markbad command to + automate retries and handling of possibly newly detected bad blocks if the + nand write command fails. + It can also be used manually by users having seen some NAND errors in logs to + search the root cause of these errors. + The underlying nand_torture() function is also useful for code willing to + automate actions following a nand->write() error. This would e.g. be required + in order to program or update safely firmware to NAND, especially for the UBI + part of such firmware. + NAND locking command (for chips with active LOCKPRE pin) -- cgit v1.2.3