thanx! with this patch,TEAM GROUP SD 64GB sd card works fine.Thank you for testing. I've checked in this fix -- not sure if the hardware is meant to run in SDR50 mode anyway..
Perhaps the mode should be downgraded if the kernel can't communicate with the card. The picture from Jun shows "cmd end bit error", which could be a good place to decide to try a slower mode.
Considering that many cards work fine at SDR50 speeds in both GNU/Linux and NetBSD, I'd say this is a card issue, not an unsupported-by-Pi issue.
John