Hello,
I have an interesting issue going on an am335x regarding the NAND controller. When copying data from NAND to the SD-card it is really easy to get uncorrectable ECC errors from the ELM wich causes UBI to retry the read.
The problematic function has been tracked down to the omap_read_buf_pref and the polled reading in the beginning.
It seems that it causes a corrupted read from the GPMC. The remedy seems to be an ever so slight delay before the read is performed, then it is fine.
The solution I have currently is to have the prefetch engine fetch all the bytes and not do a polled read at all but it has been tested that if the polled read is done after the the prefetch read it is also fine.
Also if I put the device in pure polled mode it fails in all NAND timing modes except mode 0.
Anyone have any good ideas why this happens?
BR
Henrik
