On 09/04/2014 05:45 PM, Robert Nelson wrote: > On Thu, Sep 4, 2014 at 4:22 PM, Robert Nelson <robertcnel...@gmail.com> wrote: >>>> >>>> dd if=MLO of=/dev/sdX count=1 seek=1 conv=notrunc bs=128k >>>> dd if=u-boot.img of=/dev/sdX count=2 seek=1 conv=notrunc bs=384k >>>> >>>> So far i've only got it to reliabley work on omap4+ bootroms (which >>>> include the am335x).. so beagle/beagle-xm, not yet... >>> >>> You need to be really good about wiping out the FAT partition before you >>> do this or you'll run into problems of the ROM finding things that >>> aren't there anymore. Doing a dd if=/dev/zero of=/dev/sdXp1 before >>> re-doing the partition table is a good idea. >> >> Yeah, we do both a zero out and read back flush for good measures... >> >> dd if=/dev/zero of=${media} bs=1M count=100 || drive_error_ro >> sync >> dd if=${media} of=/dev/null bs=1M count=100 >> sync >> >> mkfs.ext4 in debian jessie started getting picky, so we had to zero >> out past the end of the first partition, otherwise it still saw the >> old partition and warned us. (therefor we couldn't no longer script >> that..) > > Tom, by the way.. When we 'update' a dd'ed bootloader, how many > sectors should be blank with /dev/zero to be on the safe side. (this > is for situations where i don't wan to blow out mbr, but just want to > update the mlo/u-boot.img)
Just updating an existing one? This isn't NAND/NOR so you're fine just overwriting things in place. You can even store a back-up MLO at 0x200 offset (ROM checks 0x0, 0x100 0x200 and 0x300 and we cut the last location off the list and put U-Boot there). -- Tom -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.