5.15.11-1-MANJARO-ARM, without problems. I had the same errors when I was using orginal am6.dts files. It was because the HS200 controller wasn’t recognized. I think it was something with max freqency variable was to low. I used the variables from khadad and got HS200 controller recognized and the the error messages was gone
/* eMMC */
&sd_emmc_c {
status = "okay";
pinctrl-0 = <&emmc_ctrl_pins>, <&emmc_data_8b_pins>, <&emmc_ds_pins>;
pinctrl-1 = <&emmc_clk_gate_pins>;
pinctrl-names = "default", "clk-gate";
bus-width = <8>;
cap-mmc-highspeed;
mmc-ddr-1_8v;
mmc-hs200-1_8v;
max-frequency = <200000000>;
disable-wp;
mmc-pwrseq = <&emmc_pwrseq>;
vmmc-supply = <&vcc_3v3>;
vqmmc-supply = <&emmc_1v8>;
};