Hi,
We have three DM385 boards. In these, two boards are having SD booting issue.
We checked all the possibilities in hardware part, like continuity test between processor & SD card holder, Boot configuration and SD lines pull up values(10K).
Note: There is no issue in UART boot.
Initially board 2 was booting properly. After some days, we got the following error,
===================================================================
mmc0: host does not support reading read-only switch. assuming write-enable.
mmc0: new high speed SDHC card at address e624
mmcblk0: mmc0:e624 SU04G 3.69 GiB
mmcblk0: retrying using single block read
mmcblk0: error -110 sending status comand
mmcblk0: error -110 sending read/write command, response 0x0, card status 0x0
mmcblk0: error -110 transferring data, sector 0, nr 8, card status 0x0
===================================================================
It is also giving MMC fat load error, read and write error and hanging between some process.
These above mentioned errors are not stable, sometimes board will work normally. This normal working condition also not stable.
We have captured the SD lines waveforms and compared with working board. There was no similarity.
Recently we did board 3 bring up. Its not at all going to SD boot. This board also having SD booting issue.
Help us to resolve the issue.
Thanks in advance.
Regards,
Shanmugam Nachiappan