> From: [email protected] > > you can update u-boot from a running linux using MTD - though you > > may have to turn off the "writable" bits in the board setup > definitions > > for the low area MTD partitions first. > > Are you using NAND or NOR?
NAND (Note this is on DM355) > If you're using NAND (like us), how do you handle the fact > that you'd be > writing a different > ECC and OOB pattern than the RBL/UBL expects? This is using the EVM supplied u-boot and kernel (with various mods). I'm not sure what you mean about writing different ECC/OOB patterns, but it works for me. > See the dilemma now? If the kernel changes the ECC format and > u-boot isn't > aware > of that fact, then u-boot will happily start marking every > block it reads > as corrupt. > > That scenario is catastrophic as you wouldn't be able to figure which > blocks were > actually bad in the first place. Sure. I'm not quite sure what your exact situation is, if your running kernel is not writing ECC+OOB you are happy with maybe you would have to do something as dirty as manually formatting your OOB+ECC when writing from linux (I think MTD will let you override its idea of OOB+ECC like this), write your new u-boot and kernel at the same time like that, then reboot and everything will be changed over to the new scheme. I assume you have enough RAM or SD card space or something to be able to rewrite all the NAND flash areas you need to in one go. Just hope you don't have a power failure part way through, or write to a completely alternate area of NAND and switch at the end, if you have enough (I have this luxury) These things could be fiddly and a reasonable amount of work, I suppose it depends how many devices you have in the field and how much it would cost to recall them. Of course, it would be nice if our employers let us take the time to get things right before shipping products, but sadly this is the real world. -- Jon Povey, Design Engineer [email protected] | +44(0)1280 825983 Racelogic is a limited company registered in England. Registered number 2743719 . Registered Office Unit 10, Swan Business Centre, Osier Way, Buckingham, Bucks, MK18 1TB . The information contained in this electronic mail transmission is intended by Racelogic Ltd for the use of the named individual or entity to which it is directed and may contain information that is confidential or privileged. If you have received this electronic mail transmission in error, please delete it from your system without copying or forwarding it, and notify the sender of the error by reply email so that the sender's address records can be corrected. The views expressed by the sender of this communication do not necessarily represent those of Racelogic Ltd. Please note that Racelogic reserves the right to monitor e-mail communications passing through its network _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
