Hi, > I would advise against using any sd-uhs- mode for sd-card on Rockchip > RK356x boards because of a timing issue during boot between mmc, > regulator and IO-domain drivers. This problem seems to occur only on rk356x? > Ideally this race condition should be solved instead of limiting use > of UHS modes. However, use of sd-uhs-sdr50 is typically more forgiving > and has been used on other boards. It seems that sd-uhs-sdr50 does not need 1.8V IO voltage. I tested the speed on a rk3528 board with sdio wifi: (The IO voltage of sdio on this board is 3.3V) highspeed: 170Mbps DL sdr50: 290Mbps DL sdr104: 290Mbps DL So sdr50 should be safe. Thanks, Chukun -- 2.25.1
