Hello, thank you very much for your work! > +dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-rock-4c-plus.dtb this is not an objection, just a note for me, currently our(Radxa) u-boot try to load "rk3399-rock-pi-4c-plus.dtb". > +#include "rk3399-opp.dtsi" ROCK 4C+ has RK3399-T. it needs different opp table. > + aliases { > + mmc0 = &sdmmc; please add mmc1 = &sdhci; as like as other ROCK (Pi) 4 series. > +&hdmi_sound { > + status = "okay"; > +}; please add &i2s2 { status = "okay"; }; too. > +&sdmmc { > + bus-width = <4>; > + cap-mmc-highspeed; > + cap-sd-highspeed; > + card-detect-delay = <800>; > + disable-wp; > + pinctrl-names = "default"; > + pinctrl-0 = <&sdmmc_clk &sdmmc_cd &sdmmc_cmd &sdmmc_bus4>; > + vqmmc-supply = <&vccio_sd>; > + status = "okay"; > +}; does card detect work for you? it doesn't work for me. I think it needs cd-gpios = <&gpio0 RK_PA7 GPIO_ACTIVE_LOW>; instead of "&sdmmc_cd". Best regards, -- FUKAUMI Naoki