i.MX ProcessorsのトピックRe: Using DATA3 as cd pin in SD card

Using DATA3 as cd pin in SD card

Robbi — Thu, 08 May 2025 11:15:17 GMT

Hi team,

I'm working with i.MX91 custom board, the major difference in SD Card interface is EVK is using dedicated GPIO for card detection, but we are using DATA3. I changed Kernel dts file as (Mentioned in RM DATA3 should be pull-down)

&usdhc2 {

pinctrl-names = "default", "state_100mhz", "state_200mhz", "sleep";

pinctrl-0 = <&pinctrl_usdhc2>;

pinctrl-1 = <&pinctrl_usdhc2_100mhz>;

pinctrl-2 = <&pinctrl_usdhc2_200mhz>;

pinctrl-3 = <&pinctrl_usdhc2_sleep>;

cd-gpios = <0>;

fsl,cd-gpio-wakeup-disable;

fsl,cd-controller;

bus-width = <4>;

status = "okay";

no-sdio;

};

and iomux:

pinctrl_usdhc2: usdhc2grp {

fsl,pins = <

MX91_PAD_SD2_CLK__USDHC2_CLK 0x1582

MX91_PAD_SD2_CMD__USDHC2_CMD 0x1382

MX91_PAD_SD2_DATA0__USDHC2_DATA0 0x1382

MX91_PAD_SD2_DATA1__USDHC2_DATA1 0x1382

MX91_PAD_SD2_DATA2__USDHC2_DATA2 0x1382

MX91_PAD_SD2_DATA3__USDHC2_DATA3 0x1582

};

pinctrl_usdhc2_100mhz: usdhc2-100mhzgrp {

fsl,pins = <

MX91_PAD_SD2_CLK__USDHC2_CLK 0x158e

MX91_PAD_SD2_CMD__USDHC2_CMD 0x138e

MX91_PAD_SD2_DATA0__USDHC2_DATA0 0x138e

MX91_PAD_SD2_DATA1__USDHC2_DATA1 0x138e

MX91_PAD_SD2_DATA2__USDHC2_DATA2 0x138e

MX91_PAD_SD2_DATA3__USDHC2_DATA3 0x158e

};

pinctrl_usdhc2_200mhz: usdhc2-200mhzgrp {

fsl,pins = <

MX91_PAD_SD2_CLK__USDHC2_CLK 0x15fe

MX91_PAD_SD2_CMD__USDHC2_CMD 0x13fe

MX91_PAD_SD2_DATA0__USDHC2_DATA0 0x13fe

MX91_PAD_SD2_DATA1__USDHC2_DATA1 0x13fe

MX91_PAD_SD2_DATA2__USDHC2_DATA2 0x13fe

MX91_PAD_SD2_DATA3__USDHC2_DATA3 0x15fe

};

pinctrl_usdhc2_sleep: usdhc2grpsleep {

fsl,pins = <

MX91_PAD_SD2_CLK__GPIO3_IO1 0x51e

MX91_PAD_SD2_CMD__GPIO3_IO2 0x51e

MX91_PAD_SD2_DATA0__GPIO3_IO3 0x51e

MX91_PAD_SD2_DATA1__GPIO3_IO4 0x51e

MX91_PAD_SD2_DATA2__GPIO3_IO5 0x51e

MX91_PAD_SD2_DATA3__GPIO3_IO6 0x51e

};

slight changes are done, but after power-up, SPL unable to detect MMC1. Kindly help me to sort the issue.

Thanks.

Re: Using DATA3 as cd pin in SD card

Chavira — Thu, 08 May 2025 14:24:03 GMT

HI @Robbi!
Thank you for contacting NXP Support!

The configuration that I recommend is the next:

The pinctrl looks good.

Do you want to boot from SD card using usdhc2?

This device tree is the u-boot device tree or Linux-device tree?

What BSP version are you using?

Best Regards!

Chavira

Re: Using DATA3 as cd pin in SD card

Robbi — Fri, 09 May 2025 06:43:00 GMT

Thanks @Chavira ,

For the response, this kernel dts, initially I left u-boot dts same as imx91 EVK but later I tried and changed. still same error MMC1 not detecting.

Is this same dts node should be in u-boot dts?
Any other files need to be modified.

Thanks.

Robbi

Re: Using DATA3 as cd pin in SD card

Robbi — Fri, 09 May 2025 06:56:52 GMT

BSP = 6.6.52

Re: Using DATA3 as cd pin in SD card

Robbi — Mon, 12 May 2025 12:14:32 GMT

Hi @Chavira ,

Please suggest me what changes need to be done, to boot from sd card.

Re: Using DATA3 as cd pin in SD card

Chavira — Mon, 12 May 2025 13:30:37 GMT

HI @Robbi!

Yes the changes should be done in U-boot device tree too.

Can you share the schematic of the SD connections?

Best Regards!

Chavira

Re: Using DATA3 as cd pin in SD card

Robbi — Mon, 12 May 2025 13:53:18 GMT

Please find the attached image.

And the interface of pins with IMX91, where SD2_CD_B is not used.

[AA19] SD2_CLK	SD2_CLK
[Y19] SD2_CMD	SD2_CMD
[Y18] SD2_DATA0	SD2_DATA0
[AA18] SD2_DATA1	SD2_DATA1
[Y20] SD2_DATA2	SD2_DATA2
[AA20] SD2_DATA3	SD2_DATA3
[AA17] SD2_RESET_B	SD2_nRST

Thanks

Robbi

Re: Using DATA3 as cd pin in SD card

Robbi — Tue, 13 May 2025 12:05:14 GMT

And while booting from emmc try to detect using lsblk command, but unable to find, displays error above message

Re: Using DATA3 as cd pin in SD card

Chavira — Tue, 13 May 2025 15:34:03 GMT

Hi @Robbi!

I can boot u-boot without the error message.

The u-boot device tree should be the next:

&usdhc2 { pinctrl-names = "default", "state_100mhz", "state_200mhz"; pinctrl-0 = <&pinctrl_usdhc2>; pinctrl-1 = <&pinctrl_usdhc2_100mhz>; pinctrl-2 = <&pinctrl_usdhc2_200mhz>; vmmc-supply = <&reg_usdhc2_vmmc>; bus-width = <4>; non-removable; status = "okay"; no-sdio; no-mmc; }; pinctrl_usdhc2: usdhc2grp { fsl,pins = < MX93_PAD_SD2_CLK__USDHC2_CLK 0x1582 MX93_PAD_SD2_CMD__USDHC2_CMD 0x40001382 MX93_PAD_SD2_DATA0__USDHC2_DATA0 0x40001382 MX93_PAD_SD2_DATA1__USDHC2_DATA1 0x40001382 MX93_PAD_SD2_DATA2__USDHC2_DATA2 0x40001382 MX93_PAD_SD2_DATA3__USDHC2_DATA3 0x40001382 MX93_PAD_SD2_VSELECT__USDHC2_VSELECT 0x51e >; };

Result:

U-boot booting without error from SD card

If you want to boot from SD card there is not needed the cd function since the SD should not be disconnected from the board.

Your custom board only has SD boot?

I made the next changes in Linux Kernel device tree and the card detection is working good without CD gpio configured:

&usdhc2 { pinctrl-names = "default", "state_100mhz", "state_200mhz", "sleep"; pinctrl-0 = <&pinctrl_usdhc2>; pinctrl-1 = <&pinctrl_usdhc2_100mhz>; pinctrl-2 = <&pinctrl_usdhc2_200mhz>; pinctrl-3 = <&pinctrl_usdhc2_sleep>; broken-cd; fsl,cd-gpio-wakeup-disable; vmmc-supply = <&reg_usdhc2_vmmc>; bus-width = <4>; status = "okay"; no-sdio; no-mmc; }; pinctrl_usdhc2: usdhc2grp { fsl,pins = < MX91_PAD_SD2_CLK__USDHC2_CLK 0x1582 MX91_PAD_SD2_CMD__USDHC2_CMD 0x1382 MX91_PAD_SD2_DATA0__USDHC2_DATA0 0x1382 MX91_PAD_SD2_DATA1__USDHC2_DATA1 0x1382 MX91_PAD_SD2_DATA2__USDHC2_DATA2 0x1382 MX91_PAD_SD2_DATA3__USDHC2_DATA3 0x1382 MX91_PAD_SD2_VSELECT__USDHC2_VSELECT 0x51e >; }; pinctrl_usdhc2_100mhz: usdhc2-100mhzgrp { fsl,pins = < MX91_PAD_SD2_CLK__USDHC2_CLK 0x158e MX91_PAD_SD2_CMD__USDHC2_CMD 0x138e MX91_PAD_SD2_DATA0__USDHC2_DATA0 0x138e MX91_PAD_SD2_DATA1__USDHC2_DATA1 0x138e MX91_PAD_SD2_DATA2__USDHC2_DATA2 0x138e MX91_PAD_SD2_DATA3__USDHC2_DATA3 0x138e MX91_PAD_SD2_VSELECT__USDHC2_VSELECT 0x51e >; }; pinctrl_usdhc2_200mhz: usdhc2-200mhzgrp { fsl,pins = < MX91_PAD_SD2_CLK__USDHC2_CLK 0x15fe MX91_PAD_SD2_CMD__USDHC2_CMD 0x13fe MX91_PAD_SD2_DATA0__USDHC2_DATA0 0x13fe MX91_PAD_SD2_DATA1__USDHC2_DATA1 0x13fe MX91_PAD_SD2_DATA2__USDHC2_DATA2 0x13fe MX91_PAD_SD2_DATA3__USDHC2_DATA3 0x13fe MX91_PAD_SD2_VSELECT__USDHC2_VSELECT 0x51e >; }; pinctrl_usdhc2_sleep: usdhc2grpsleep { fsl,pins = < MX91_PAD_SD2_CLK__GPIO3_IO1 0x51e MX91_PAD_SD2_CMD__GPIO3_IO2 0x51e MX91_PAD_SD2_DATA0__GPIO3_IO3 0x51e MX91_PAD_SD2_DATA1__GPIO3_IO4 0x51e MX91_PAD_SD2_DATA2__GPIO3_IO5 0x51e MX91_PAD_SD2_DATA3__GPIO3_IO6 0x51e MX91_PAD_SD2_VSELECT__GPIO3_IO19 0x51e >; };

Result:

Booting from MMC the SD cards are detected and mounted in the system without errors

Best Regards!

Chavira