My custom boards implement SD0 to boot up and SD1 to interface to wifi module. My wifi module support SD3.0 spec. So I provide 1.8v to sdio signals of wifi module. Meanwhile I also notice NVCC_NAND from imx6ull should be connected with 1.8v.
after boot up, I noticed kernel found a new high speed SDIO card but not a ultra high speed SDIO card.
After I ran "cat /sys/kernel/debug/mmc1/ios", I got that system found a sd2.0 card. That's a problem.
imx6ull14x14evk login: root
root@imx6ull14x14evk:~# cat /sys/kernel/debug/mmc1/ios
clock: 50000000 Hz
actual clock: 44000000 Hz
vdd: 21 (3.3 ~ 3.4 V)
bus mode: 2 (push-pull)
chip select: 0 (don't care)
power mode: 2 (on)
bus width: 2 (4 bits)
timing spec: 2 (sd high-speed)
signal voltage: 0 (3.30 V)
My dts is almost the same as imx6ull-14x14-evk.dts. What else should I be concerned?
The log file and dts file are attached.