Re: ARM iMX6sx board fails to boot with kernel 6.17

[Sergey Organov <sorganov@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 2504 bytes --]

Fabio Estevam <festevam@gmail.com> writes:

> Hi Sergey,
>
> On Tue, Oct 7, 2025 at 6:17 PM Sergey Organov <sorganov@gmail.com> wrote:
>>
>> Please see attached minimum DTS. Maybe it misses something? Shouldn't
>> DTS describe how eMMC chip is powered, provided it's powered from NXP
>> MMPF0100F6ANES PMIC? I didn't find any hints in other DTS'es.
>
> Yes, the dts should describe the eMMC power supplies.
>
> The properties are: vmmc-supply and vqmmc-supply.
>
> Check arch/arm/boot/dts/nxp/imx/imx6qdl-colibri.dtsi for reference.

This uses:

        pmic: pmic@8 {                                                                                
                compatible = "fsl,pfuze100";                                                          

that doesn't look like the one I need, and I don't see anything among
Documentation/devicetree/bindings/regulator/* for the NXP MMPF0100F6ANES
PMIC that is used on my board.

Does it mean that this regulator is unsupported? If so, doesn't it mean
that kernel simply won't touch it, and thus it can't be the cause of the
hang?

Anyway, I added naive fixed regulators (see attached modified DTS), but
it didn't change the outcome.

>
>> The point of hang is not entirely deterministic either, that suggests
>> it's some power problem indeed. It may hang after random line among the
>> following depending on exact build and sometimes even from run-to-run:
>>
>> ...
>> mmc0: SDHCI controller on 219c000.mmc [219c000.mmc] using ADMA
>> Loading compiled-in X.509 certificates
>> clk: Disabling unused clocks
>> PM: genpd: Disabling unused power domains
>
> Does it hang if you pass "pm_genpd_ignore_unused" and
> "clk_ignore_unused" in the kernel command line?

Yep, it still hangs (it's pd_ignore_unused, not pm_genpd_ignore_unused,
btw):

clk: Not disabling unused clocks                   
PM: genpd: Not disabling unused power domains      
check access for rdinit=/init failed: -2, ignoring 
Waiting for root device /dev/mmcblk0p3...

and I recall I've already tried it first thing to disable this right in
the code to no avail either.

>
>> check access for rdinit=/init failed: -2, ignoring
>> Waiting for root device /dev/mmcblk0p2...
>>
>> Also, I just tried to compile entire kernel with -DDEBUG, and it starts
>> to see the eMMC, though still hangs not ever mounting the root FS:
>
> I saw Ulf's response about a potential regression in 6.17.
>
> Do you see the hang with 6.16?

Yep, 6.16 still hangs for me the same way.

-- Sergey Organov


[-- Attachment #2: troublesome minimum dts --]
[-- Type: text/plain, Size: 1917 bytes --]

/dts-v1/;

#include "../imx6sx.dtsi"

/ {
	compatible = "javad,imx6sx", "fsl,imx6sx";

	chosen {
		stdout-path = &uart1;
	};

	aliases {
		mmc0 = &usdhc4;
		mmc1 = &usdhc3;
		mmc2 = &usdhc2;
		mmc3 = &usdhc1;
	};

	memory@80000000 {
		device_type = "memory";
		reg = <0x80000000 0x40000000>;
	};

	reg_module_3v3: regulator-module-3v3 {
		compatible = "regulator-fixed";
		regulator-name = "+V3.3";
		regulator-min-microvolt = <3300000>;
		regulator-max-microvolt = <3300000>;
		regulator-always-on;
	};

	reg_module_1v8: regulator-module-1v8 {
		compatible = "regulator-fixed";
		regulator-name = "+V1.8";
		regulator-min-microvolt = <1800000>;
		regulator-max-microvolt = <1800000>;
		regulator-always-on;
	};

};

&usdhc4 {
	pinctrl-names = "default";
	pinctrl-0 = <&pinctrl_usdhc4>;
	bus-width = <8>;
	non-removable;
	keep-power-in-suspend;
	vmmc-supply = <&reg_module_3v3>;
	vqmmc-supply = <&reg_module_1v8>;
	status = "okay";
};

&uart1 {
	pinctrl-names = "default";
	pinctrl-0 = <&pinctrl_uart1>;
	dma-names = "";
	uart-has-rtscts;
	status = "okay";
};

&iomuxc {
	pinctrl-names = "default";
	imx6x-sdb {
		pinctrl_usdhc4: usdhc4grp {
			fsl,pins = <
				MX6SX_PAD_SD4_CLK__USDHC4_CLK		0x10059
				MX6SX_PAD_SD4_CMD__USDHC4_CMD		0x17059
				MX6SX_PAD_SD4_DATA0__USDHC4_DATA0	0x17059
				MX6SX_PAD_SD4_DATA1__USDHC4_DATA1	0x17059
				MX6SX_PAD_SD4_DATA2__USDHC4_DATA2	0x17059
				MX6SX_PAD_SD4_DATA3__USDHC4_DATA3	0x17059
				MX6SX_PAD_SD4_DATA4__USDHC4_DATA4	0x17059
				MX6SX_PAD_SD4_DATA5__USDHC4_DATA5	0x17059
				MX6SX_PAD_SD4_DATA6__USDHC4_DATA6	0x17059
				MX6SX_PAD_SD4_DATA7__USDHC4_DATA7	0x17059
				MX6SX_PAD_SD4_RESET_B__USDHC4_RESET_B	0x17068
			>;
		};
		pinctrl_uart1: uart1grp {
			fsl,pins = <
				MX6SX_PAD_ENET2_CRS__UART1_TX		0x1b0b1
				MX6SX_PAD_ENET2_COL__UART1_RX		0x1b0b1
				MX6SX_PAD_ENET2_TX_CLK__UART1_CTS_B	0x1b0b1
				MX6SX_PAD_ENET2_RX_CLK__UART1_RTS_B	0x1b0b1
			>;
		};
	};
};