Change eMMC operating mode to HS200

nirmalluhana — Mon, 16 Sep 2019 11:29:05 GMT

Hello,

Release: Yocto-Sumo (4.14.78_1.0.0_GA)

Board: i.MX8MQ based custom board

We designed iMX8MQ based custom board and used eMMC as booting option.

Right now, our eMMC is operated in HS400 mode as mentioned in kernel debug logs.

root@imx8mqpicoitx:~# cat /sys/kernel/debug/mmc0/ios
clock:          200000000 Hz
actual clock:   200000000 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:      3 (8 bits)
timing spec:    10 (mmc HS400)
signal voltage: 1 (1.80 V)
driver type:    0 (driver type B)
root@imx8mqpicoitx:~#

We want to change eMMC operating mode to HS200.

So, for that which changes we have to change in dts file or in eMMC driver source?

Best regards,

Nirmal

Re: Change eMMC operating mode to HS200

gusarambula — Tue, 01 Oct 2019 19:09:58 GMT

Hello Nirmal,

The following thread may be of help:

https://community.nxp.com/thread/494187

Regards,

topic Re: Change eMMC operating mode to HS200 in i.MX Processors

Change eMMC operating mode to HS200

Re: Change eMMC operating mode to HS200