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Using the MMC0 bus instead of MMC1 on roadrunner

Wirings

Place a 68k pull-up resistor on DATA 0,1,2,3 and CMD

CPU line SD Signal SD Pin #
PA0 CLK 5
PA1 CMD 2
PA2 DATA 0 7
PA3 DATA 1 8
PA4 DATA 2 9
PA5 DATA 3 1
VCC 4
GND 3,6
PA13 GND (CD)

Device tree binding

ahb {

    ...

    sdmmc0: sdio-host@a0000000 {
        bus-width = <4>;
        pinctrl-names = "default";
        no-1-8-v;
        non-removable;  
        pinctrl-0 = <&pinctrl_sdmmc0_default>;
        status = "okay";
    };

    sdmmc1: sdio-host@b0000000 {
        bus-width = <4>;
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_sdmmc1_default>;
    };

    ...


    apb {

        ...

        pinctrl_sdmmc0_default: sdmmc0_default {
            cmd_data {
                pinmux = <PIN_PA1__SDMMC0_CMD>,
                     <PIN_PA2__SDMMC0_DAT0>,
                     <PIN_PA3__SDMMC0_DAT1>,
                     <PIN_PA4__SDMMC0_DAT2>,
                     <PIN_PA5__SDMMC0_DAT3>;
                bias-disable;
            };

            ck_cd_rstn_vddsel {
                pinmux = <PIN_PA0__SDMMC0_CK>,
                     <PIN_PA13__SDMMC0_CD>;
                bias-disable;
            };
        };

        ...


    };

    ...


};

Roadrunner technical documentation Buy on-line

Bruna Mandolino