From: Loren Amelang <lorenamel...@gmail.com> Reply-To: <beagleboard@googlegroups.com> Date: Monday, February 17, 2014 at 10:17 PM To: <beagleboard@googlegroups.com> Subject: Re: [beagleboard] BBB no autoboot of uSD
> Robert, > > My BBB absolutely must default to booting from the uSD. I know I could short > the boot switch, or move pull-up/down resistors, or create a hardware switch > gated from reset, but I don't want to lose hardware compatibility with other > BBB boards, or give up the option of manually booting from eMMC occasionally. > The code you suggest here sounds perfect - but I'm not positive what to do > with it. From the formatting of the text, I suspect it is intended to be > compiled into a new u-boot.img and MLO image, but I'm not sure how to do that. > > Before I spend hours learning how, is there a chance I could just insert the > basic ideas into my uEnv.txt as "mmcboot=mmc dev 0; if mmc rescan ; then ..."? > It does look like uEnv.txt is read before the mmcboot command runs... > > If so, does it have to be run together into a single ';' separated line, or > can I leave the '\' line continuations in to make it more readable? > > I suspect uEnv.txt would not want the double-quotes? Or Windows <CRLF> line > endings... > > If that is totally hopeless, can you suggest a tutorial on building a new > u-boot.img and MLO with this code? > > Thank you for any clues, See if this helps: http://processors.wiki.ti.com/index.php/AM335x_U-Boot_User's_Guide Otherwise, read the u-boot manual. Regards, John > > Loren > > On Thursday, January 2, 2014 2:16:47 PM UTC-8, RobertCNelson wrote: >> I have mine setup as the following.. >> >> + "mmc dev 0; if mmc rescan ; then " \ >> + "gpio set 54; " \ >> + "setenv mmcdev 0; " \ >> + "echo SD/MMC found on device ${mmcdev}; " \ >> + "if run loadbootenv; then " \ >> + "run importbootenv; " \ >> + "fi; " \ >> + "gpio set 55; " \ >> + "echo Checking if uenvcmd is set ...;" \ >> + "if test -n $uenvcmd; then " \ >> + "gpio set 56; " \ >> + "echo Running uenvcmd ...; " \ >> + "run uenvcmd;" \ >> + "fi; " \ >> + "echo; echo uenvcmd was not defined in uEnv.txt ...; >> echo trying eMMC (BeagleBone Black) ...; echo;" \ >> + "fi;" \ >> + "mmc dev 1; if mmc rescan ; then " \ >> + "gpio set 54; " \ >> + "setenv mmcdev 1; " \ >> + "echo SD/MMC found on device ${mmcdev}; " \ >> + "if run loadbootenv; then " \ >> + "run importbootenv; " \ >> + "fi; " \ >> + "gpio set 55; " \ >> + "echo Checking if uenvcmd is set ...;" \ >> + "if test -n $uenvcmd; then " \ >> + "gpio set 56; " \ >> + "echo Running uenvcmd ...; " \ >> + "run uenvcmd;" \ >> + "fi; " \ >> + "echo; echo uenvcmd was not defined in uEnv.txt ...; >> echo halting ...; echo;" \ >> + "fi;" \ >> > > -- > 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/groups/opt_out. -- 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/groups/opt_out.