From mboxrd@z Thu Jan 1 00:00:00 1970 From: Detlev Zundel Date: Fri, 17 Jan 2014 15:58:50 +0100 Subject: [U-Boot] Fat write problem In-Reply-To: <15AE5A936F5E3A42A9144E66875A0A8938AFC4@server1-derijp.CLB-Benelux.lokaal> (Ruud Commandeur's message of "Wed, 15 Jan 2014 12:15:04 +0100") References: <15AE5A936F5E3A42A9144E66875A0A8938AFC4@server1-derijp.CLB-Benelux.lokaal> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Ruud, > This week I decided to do some further research and testing regarding > this problem. > With the image I had from the previous time, I could immediately > reproduce it and > by adding more and more debug prints, I tried to find the cause. Sofar, > I have not > succeeded in this yet. > > However: later on I started testing with a freshly formatted drive (32 > MB FAT partition) > and kept repeating the fatwrite command: > > fatwrite mmc 0:1 42000000 test-x 200 > > where x runs from 1, 2,3 and further. And this way I could reproduce it > quite easily. > Writing always fails for the 32nd file. This is with the partition > formatted with a 512 byte > sector size and a cluster size of 4. If the cluster size is 1 (formatted > by Windows), > it already fails at the 8th file. > > If I create a subdirectory (from Linux) with already 24 files in it, I > can still write 29 files > and it fails at number 30. Also, if earlier files were deleted from the > root-directory, they > still count in the total number of files here. > > If I take out the card where u-boot fails to write new files, I can > still add new files from > my PC with Linux or Windows. > > I tested with both long and short filenames (same result), VFAT is > enabled. > > I hope this gives you all some more information about this problem and > perhaps it is even a > known problem (limited number of files in the root directory?). I know > it is voor FAT16, but > that was 512 entries if I am correct. Thanks for the extensive research into this problem. For people to help, I think the barrier of reproducing the problem is "somewhat high", so it occurred to me if you can help setup a very easy test for people to work on. Would you be able to generate a small image that one can dd to a mmc card and then immediately provoke the error? If you don't have any hosting space, as a last resort I'd be fine for you to put it on our wiki [1]. Cheers Detlev [1] http://www.denx.de/wiki/view/U-Boot/TooBigPatches -- Golden rule #12: When the comments do not match the code, they probably are both wrong. -- Steven Rostedt <1300126962.9910.128.camel@gandalf.stny.rr.com> -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu at denx.de