imx8qm lvds 1080p

[omerbenezra]

hi,

i want to get the LVDS output 1920X1080 @ 60hz on double lvds in format RGB888

we did change in the dtsi file like this:

fsl,data-width = <24>;
        display-timings {
            lvds {
                clock-frequency = <148500000>;
                hactive = <1920>;
                vactive = <1080>;
                hback-porch = <148>;
                hfront-porch = <88>;
                vback-porch = <36>;
                vfront-porch = <4>;
                hsync-len = <5>;
                vsync-len = <2>;
                hsync-active = <0>;
                vsync-active = <0>;
                de-active = <1>;
                pixelclk-active = <0>;
            };
        };
    };
};

but we still getting in the fbset that the format

rgba 5/11,6/5,5/0,0/0

how can we change it to real 888

thank you

omer.

[joanxie]

could you share your uboot settings? if  you want to set frame buffer as 32bits, try to use the patch as below:

diff --git a/drivers/gpu/drm/imx/imx-drm-core.c b/drivers/gpu/drm/imx/imx-drm-core.c
index 2fb93cf..f9a4db7 100644
--- a/drivers/gpu/drm/imx/imx-drm-core.c
+++ b/drivers/gpu/drm/imx/imx-drm-core.c
@@ -42,7 +42,7 @@ struct imx_drm_crtc {
 };

 #if IS_ENABLED(CONFIG_DRM_FBDEV_EMULATION)
-static int legacyfb_depth = 16;
+static int legacyfb_depth = 32;
 module_param(legacyfb_depth, int, 0444);
 #endif

[omerbenezra]

Thank you. 

Its working. 

Do you know how to set the input of the fb to RGBA 6666? 

Omer. 

[joanxie]

I think it should be same as this, keep the framebuffer as 32bits