[lkml]   [2003]   [Jan]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Fwd: File system corruption
On Wed, Jan 08, 2003 at 02:15:06PM +0000, Alan Cox wrote:
> On Wed, 2003-01-08 at 11:35, Paul wrote:
> > What I have found is that just after the start of a sector, usually 43 to 45
> > bytes, 6 bytes are skipped and the sequence starts again. This continues
> > until the next sector starts, where the sequence corrects. This appears to
> > happen every 65536 bytes or some multiple of 65536. It may skip three blocks
> > of 65536 and then corrupt on the next block of 65536 bytes.
> Ok that I'm afraid bears no resemblance to anything the software side
> does (we write in chunks but we do single PIO block transfers of each
> sector).

After examining the resulting image, Paul has a "clock" line to his
flash device that is a bit noisy. This occasionally causes one
16-bit entity to be clocked into the device twice.

To detect this going wrong, we could (but only as a configurable
option), write 255 16-bit words to the device (remember this is PIO!),
check that DRQ is still active and only then write the last word.
(at which point DRQ should go inactive).


** ** ** +31-15-2600998 **
*-- BitWizard writes Linux device drivers for any device you may have! --*
* The Worlds Ecosystem is a stable system. Stable systems may experience *
* excursions from the stable situation. We are currently in such an *
* excursion: The stable situation does not include humans. ***************
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:32    [W:0.046 / U:0.316 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site