Roadrunner technical documentation Buy on-line
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;
};
};
...
};
...
};
