Hi,
I'm encountering strange random problem on some of our boards based on i.MX7D during production.
They just can't flash the eMMc using UUU tools, because U-boot boots partially, or does not boot at all in RAM. When the board boots partially, it starts to boot and than just randomly stop. I have found common thing in boot logs, when board is able to boot partially, that running CPU frequency is degraded to 396MHz, instead of normal 792MHz.
U-Boot 2022.04-lf_v2022.04+g16e8414193 (Oct 08 2022 - 13:33:43 +0000)
CPU: i.MX7D rev1.3 1000 MHz (running at 396 MHz)
CPU: Extended Commercial temperature grade (-20C to 105C) at 31C
Reset cause: POR
DRAM: 512 MiB
I have tried to disable CONFIG_IMX_THERMAL, but no change and CPU temperature is around 33°C, so it should be OK.
When I load DDR test using JTAG, it is running OK without any error.
Any ideas, what could be causing the problems?
Probably some race situation/parameters, or HW problem, but I'm quite out of options, what to try.
Thanks in advance,
Michal Spanik
