[U-Boot] [PATCH 2/2] imx: mx6ul_14x14_evk: convert to DM_VIDEO

[Peng Fan]

> Subject: RE: [U-Boot] [PATCH 2/2] imx: mx6ul_14x14_evk: convert to
> DM_VIDEO
> 
> > Subject: Re: [U-Boot] [PATCH 2/2] imx: mx6ul_14x14_evk: convert to
> > DM_VIDEO
> >
> > On Fri, Aug 2, 2019 at 12:05 PM Peng Fan <peng.fan at nxp.com> wrote:
> > >
> > > HI,
> > >
> > > > Subject: Re: [PATCH 2/2] imx: mx6ul_14x14_evk: convert to DM_VIDEO
> > > >
> > > > Hi Peng,
> > > >
> > > > On Thu, Aug 1, 2019 at 3:02 AM Peng Fan <peng.fan at nxp.com> wrote:
> > > >
> > > > > +       display0: display at 0 {
> > > > > +               bits-per-pixel = <16>;
> > > > > +               bus-width = <24>;
> > > > > +
> > > > > +               display-timings {
> > > > > +                       native-mode = <&timing0>;
> > > > > +
> > > > > +                       timing0: timing0 {
> > > > > +                               clock-frequency = <9200000>;
> > > > > +                               hactive = <480>;
> > > > > +                               vactive = <272>;
> > > > > +                               hfront-porch = <8>;
> > > > > +                               hback-porch = <4>;
> > > > > +                               hsync-len = <41>;
> > > > > +                               vback-porch = <2>;
> > > > > +                               vfront-porch = <4>;
> > > > > +                               vsync-len = <10>;
> > > > > +                               hsync-active = <0>;
> > > > > +                               vsync-active = <0>;
> > > > > +                               de-active = <1>;
> > > > > +                               pixelclk-active = <0>;
> > > >
> > > > So here we have the LCD timings in the device tree, which differs
> > > > from the the devicetree in mainline.
> > > >
> > > > This is based on the old mxsfb fbdev driver, which has been
> > > > removed in
> > 5.3-rc.
> > > >
> > > > In mainline we pass the innolux,at043tn24 LCD compatible.
> > > >
> > > > Shouldn't U-Boot be able to handle the same dt-bindings as in the
> kernel?
> > >
> > > I added this node in x-u-boot.dtsi, not in common dts. If drop this
> > > display-timings, we need add a similar structure inside code just as
> > > kernel
> > did.
> > > And need to restructure mxsfb driver.
> > >
> > > For simple, we could leave this in u-boot.dtsi.
> >
> > How about adding panel timings in panel-simple we have similar in
> > u-boot and sync equivalent dts changes from Linux?
> 
> The panel timings needs to be passed to display driver, kernel has drm-crtc for
> this, but uboot does not have it.
> 
> The method is to let display driver to find the panel node/device to get the
> timings.
> 
> Will this work?

An issue is where to get bits-per-pixel?

Thanks,
Peng.

> 
> Thanks,
> Peng.