The boot switch ... ?

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1

Can I clarify/sanity check this one please?

As of the January (or thereabouts) timeframe, u-boot has been patched so that it now checks the SD card first then eMMC? (Evidence would strongly suggest this is the case J ), irrespective of boot-switch …

i.e. we’ve got something like this (obviously assumes a recently flashed board)

Power => eMMC MLO => eMMC u-boot

If (sdcard)

Load image+dtb from sd/boot

Else

Load image+dtb from emmc/boot

Which leads me to 1 other point: presumably u-boot is still set to look for /boot on the 2nd partition which is why we are still all formatting SD cards with a little bit of FAT32?

Cheers!

Ref: https://github.com/eewiki/u-boot-patches/blob/master/v2015.01/0001-am335x_evm-uEnv.txt-bootz-n-fixes.patch and others.

2

Can I clarify/sanity check this one please?

As of the January (or thereabouts) timeframe, u-boot has been patched so
that it now checks the SD card first then eMMC? (Evidence would strongly
suggest this is the case J ), irrespective of boot-switch …

i.e. we’ve got something like this (obviously assumes a recently flashed
board)

Power => eMMC MLO => eMMC u-boot

If (sdcard)

   Load image+dtb from sd/boot

Else

      Load image+dtb from emmc/boot

if (sdcard)
   if ((partition 1)/uEnv.txt && uenvcmd != "")
      run uenvccmd (aka old eMMC mode..)
   fi
   if ((partition 1) /boot.scr)
      run boot.scr
   fi
   if ((partition 1) /boot/boot.scr)
      run /boot/boot.scr
   fi

   for ( 1 -> 7)
   if ((partition x) /boot/uEnv.txt && uname_r != NULL)
     uname_boot
   fi
else if (eMMC)
   if ((partition 1)/uEnv.txt && uenvcmd != "")
      run uenvccmd (aka old eMMC mode..)
   fi
   if ((partition 1) /boot.scr)
      run boot.scr
   fi
   if ((partition 1) /boot/boot.scr)
      run /boot/boot.scr
   fi

   for ( 1 -> 7)
   if ((partition x) /boot/uEnv.txt && uname_r != NULL)
     uname_boot
   fi
else
   u-boot ums mode... (eMMC is shared as /dev/sdX on pc over usb)
fi

Which leads me to 1 other point: presumably u-boot is still set to look for
/boot on the 2nd partition which is why we are still all formatting SD cards
with a little bit of FAT32?

the "only" reason it's fat16, is for windows users to copy files from
the 100Mb "fat" partition. Right now it serves "no" other purpose..

Regards,

3

if (sdcard)
   if ((partition 1)/uEnv.txt && uenvcmd != "")
      run uenvccmd (aka old eMMC mode..)
   fi
   if ((partition 1) /boot.scr)
      run boot.scr
   fi
   if ((partition 1) /boot/boot.scr)
      run /boot/boot.scr
   fi

   for ( 1 -> 7)
   if ((partition x) /boot/uEnv.txt && uname_r != NULL)
     uname_boot
   fi
else if (eMMC)
   if ((partition 1)/uEnv.txt && uenvcmd != "")
      run uenvccmd (aka old eMMC mode..)
   fi
   if ((partition 1) /boot.scr)
      run boot.scr
   fi
   if ((partition 1) /boot/boot.scr)
      run /boot/boot.scr
   fi

   for ( 1 -> 7)
   if ((partition x) /boot/uEnv.txt && uname_r != NULL)
     uname_boot
   fi
else
   u-boot ums mode... (eMMC is shared as /dev/sdX on pc over usb) fi

I obviously should have put more effort into the question :slight_smile: Thx++ for the detailed reply.

the "only" reason it's fat16, is for windows users to copy files from the 100Mb
"fat" partition. Right now it serves "no" other purpose..

Right.

One more point of order then: With which distro/version are the latest boards being shipped?

Thanks again Robert.

4

Boards are still being shipped with the May 2014 release. A box is to
arrive from cco this afternoon, so hopefully I'll get us on the March
2015 release asap..

http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#2015-03-01

Regards,