STM32MP257FAI3 Custom Board eMMC HS200 CRC Errors

[Saideepak]

Hello ST Community,

Custom STM32MP2 board with STM32MP257FAK fails rootfs mounting from eMMC in HS200 (CRC errors), works at 52MHz DDR.

In the device tree side only difference is removing HS200 property and added Max frequency to 52Mhz.

&sdmmc2 {
	pinctrl-names = "default", "opendrain", "sleep";
	pinctrl-0 = <&sdmmc2_b4_pins_a &sdmmc2_d47_pins_a>;
	pinctrl-1 = <&sdmmc2_b4_od_pins_a &sdmmc2_d47_pins_a>;
	pinctrl-2 = <&sdmmc2_b4_sleep_pins_a &sdmmc2_d47_sleep_pins_a>;
	non-removable;
	no-sd;
	no-sdio;
	st,neg-edge;
	bus-width = <8>;
	vmmc-supply = <&scmi_vdd_emmc>;
	vqmmc-supply = <&scmi_vddio2>;
	mmc-ddr-1_8v;
	max-frequency = <52000000>; 
	status = "okay";
};

Attached hs200 issue Log

 How to debug further to work with hs200?

[PatrickF]

Hi @Saideepak 

While keeping HS200, did you try reducing the ck_ker_sdmmc2 in clock tree to a lower frequency (e.g. 100MHz or 150 MHz) to see if any improvement ?

Then you should debug your HW (signal integrity, impedance, power supplies, etc...).

Regards