Hello
A customer has been having some other issues with booting from the eMMC on their board board based on Beaglebone HW. Occasionally it seems like u-boot can't talk to the eMMC chip and it fails to load and we get output in the console like this (for reference, mmc 1 is the eMMC):
=> boot Card did not respond to voltage select! Card did not respond to voltage select! switch to partitions #0, OK mmc1(part 0) is current device SD/MMC found on device 1 switch to partitions #0, OK mmc1(part 0) is current device SD/MMC found on device 1 reading boot.scr ** Unable to read file boot.scr ** reading uEnv.txt 528 bytes read in 5 ms (102.5 KiB/s) Loaded env from uEnv.txt Importing environment from mmc1 ... Running uenvcmd ... 32364 bytes read in 59 ms (535.2 KiB/s) Loaded am335x-boneblack.dtb mmc_read_data: timedout waiting for status! omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear mmc fail to send stop cmd ** ext4fs_devread read error - block omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear ** Can't read partition table on 1:0 ** ** Invalid partition 2 ** starting USB... USB0: Port not available. BOOTP broadcast 1 BOOTP broadcast 2 BOOTP broadcast 3 BOOTP broadcast 4 BOOTP broadcast 5 BOOTP broadcast 6 BOOTP broadcast 7 BOOTP broadcast 8 or this: mmc_read_data: timedout waiting for status! omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear SD/MMC found on device 1 omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear ** ext4fs_devread read error - block Failed to mount ext2 filesystem... ** Unrecognized filesystem type ** omap_hsmmc_send_cmd: timedout waiting on cmd inhibit to clear ** Unrecognized filesystem type ** ** No partition table - mmc 1 **
This happens maybe one out of every 10-15 times the board is rebooted. Rebooting it normally seems to fix the issue (temporarily) and it will boot into linux just fine.
The voltages on the data/clock/command lines all seem to be at 3.3V, and we're using the October 2016 release of u-boot so I don't think it's some kind of long standing bug in that. According to the schematics we're using 'MTFC2GMDEA-0M WT' for the eMMC - I don't know if this is non standard or would affect it in any way.
They are not even sure whether this is a hardware or software issue - do you have any ideas on what we can look at to see what's causing this problem to happen?
Regards Steve