On Mon, May 06, 2013 at 11:03:37PM +0200, Thomas Petazzoni wrote: > Dear Sascha Hauer, > > On Mon, 6 May 2013 22:56:31 +0200, Sascha Hauer wrote: > > > > > Barebox update will generate the correct image for the storagemedia at > > > > runtime > > > > > > What is "Barebox update" ? > > > > barebox_update is a command that you can call during runtime to update > > barebox. Over writing images directly to the storage it has the > > advantage that you can do additional sanity checks on the images. > > > > Also for example on i.MX a board specific poke table is all you need > > to bring up SDRAM. As long as you have this poke table and a devicetree > > you could use the same binary on different boards. > > Ok, makes sense. On Marvell Kirkwood, the SDRAM bring up is also done > using a set of (address, value) pairs that are part of the image > header. This mechanism is also available for Armada 370/XP, but > apparently, DDR3 requires a more dynamic tuning to find optimal > timings, so having static values in a table is no longer appropriate. > > In our case, how would barebox_update work? Would it overwrite just the > barebox.bin payload (which would require updating the 32 bits checksum > and the payload size in the header, otherwise the Marvell SoC would not > boot the image at the next reboot), or should it overwrite the whole > image (in which case it would have to re-extract the configuration and > the binary blob, and reconstruct the image at runtime) ? Probably the > first solution is the easiest one. That's up to you how you implement it. I would recommend though that if possible barebox_update should work on a naked device. This way you can do things like booting from SD card and use barebox_update to write to internal (erased) flash. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
