2404913_en-US

[#1]

MIPI-DSI on an iMX95 no clock output

Software summary
------------------------------------------------------------
Bootloader:               U-Boot
Kernel version:           6.6.138-7.6.1-devel #1 SMP PREEMPT Fri May  8 12:46:27 UTC 2026
Kernel command line:      root=PARTUUID=74fae1d2-02 ro rootwait console=tty1 console=ttyLP0,115200
Distro name:              NAME="TDX Wayland with XWayland Upstream"
Distro version:           VERSION_ID=7.6.1-devel-20260728203137-build.0
Distro variant:           -
Hostname:                 bmr-verdin-imx95-08828817
------------------------------------------------------------

Hardware info
------------------------------------------------------------
HW model:                 Toradex Verdin iMX95 WB on Verdin Development Board
Toradex version:          0089 V1.0C
Serial number:            08828817
Processor arch:           aarch64
------------------------------------------------------------

We have a custom carrier board with the Toradex Verdin iMX95. We are running the Toradex multimedia image with customizations (the base device tree is imx95-verdin-wifi-dev.dts).

We have a custom display from YES Optoelectronics (7” 1024x600) that is a MIPI-DSI 4 lane interface. I used the device tree and driver model from the raydium rm67191 as the starting point. I am able to get the power supply timing correct on startup and the backlight comes on and the BIST works (there is a pin on the display that can be pulled high for BIST), so I believe the display is working.

All four data lanes show single-ended activity but the CLK lines are at 0 volts. At power up the CLK lines start at around 200mV and then they go to 1.2 volts for a little bit but then they go to 0 volts and they stay at 0 volts.

I know the verdin SoM works because I can get the RVT70HSDNWCA0 display to work on a Mallow carrier board.

The driver goes through probe → add panel → get modes → prepare → enable.

Am I forgetting to turn on or configure a clock somewhere maybe?

What does it mean when the CLK signals (both P and N) are at 0 volts?

My overlay looks like

/dts-v1/;
/plugin/;

&mipi_dsi {
    
    status = "okay";
    panel@0 {
        compatible = "yes,ytc700tlbd";
        reg = <0>;
        reset-gpios = <&gpio2 17 1>;//GPIO_ACTIVE_HIGH>;

        power-supply = <&reg_vcc_disp_dvdd>;

        backlight = <&lvds_backlight>;

        dsi-lanes = <4>;

        port@0 {
            reg = <0>;
            panel1_in: endpoint {
                remote-endpoint = <&mipi1_panel_out>;
            };
        };
    };

    ports {
              /delete-node/ port@1;

              port@1 {
                      reg = <1>;
                      mipi1_panel_out: endpoint {
                              remote-endpoint = <&panel1_in>;
                      };
              };
    };
};

&displaymix_irqsteer {
    status = "okay";
};

&dpu {
  assigned-clocks = <&scmi_clk 80>, //IMX95_CLK_DISP1PIX>,
                          <&scmi_clk 18>, //IMX95_CLK_VIDEOPLL1_VCO>,
                          <&scmi_clk 19>; //IMX95_CLK_VIDEOPLL1>;
        assigned-clock-parents = <&scmi_clk 19>; //IMX95_CLK_VIDEOPLL1>;
        assigned-clock-rates = <0>, <3360000000>, <420000000>;
    status = "okay";
};

&pixel_interleaver {
    #address-cells = <1>;
    #size-cells = <0>;
    status = "okay";

    channel@0 {
        reg = <0>;
        status = "okay";
    };
};

&display_pixel_link {
    status = "okay";
};

Can someone confirm they were able to get a MIPI-DSI display to work with the iMX95?

Any help would be appreciated! 

Graphics & DisplayLinuxMultimediaRe: MIPI-DSI on an iMX95 no clock output

Also, here is what my clock summary looks like.

cat /sys/kernel/debug/clk/clk_summary | grep -iE "mipi|dsi|dpu|display"
ldbpll_vco                          0       0        0        4800000000  0          0     50000      Y   4b400000.display-controller     ldb_vco
ldb_pll_div7                  0       0        0        342857142   0          0     50000      Y         4b400000.display-controller     ldb                  
mipiphypllbypas               0       0        0        420000000   0          0     50000      Y         deviceless                      no_connection_id     
disp1pix                      1       1        0        46666666    0          0     50000      Y         4b400000.display-controller     pix                  
dispapb                    4       5        0        133333333   0          0     50000      Y            4b400000.display-controller     apb               
camapb                     3       6        0        133333333   0          0     50000      Y            4acf0000.dsi                    pclk              
dispocram                  1       1        0        400000000   0          0     50000      Y            4b400000.display-controller     ocram             
dispaxi                    1       1        0        800000000   0          0     50000      Y            4b400000.display-controller     axi               
mipitestbyte                     0       0        0        24000000    0          0     50000      Y      deviceless                      no_connection_id        
mipiphypllref                    1       1        0        24000000    0          0     50000      Y      4acf0000.dsi                    ref                     
mipiphycfg                       1       1        0        24000000    0          0     50000      Y      4acf0000.dsi                    cfg

Re: MIPI-DSI on an iMX95 no clock output

The target pixel clock is 51.2MHz.

Re: MIPI-DSI on an iMX95 no clock output

Hi @dastotz 

Please share the screen's pixel clock.

Best Regards,
Zhiming