Re: [PATCH v2 2/7] drm: ci: Force db410c to host mode

[Maxime Ripard]

Hi,

On Mon, Sep 04, 2023 at 07:59:26PM +0300, Dmitry Baryshkov wrote:
> On Mon, 4 Sept 2023 at 19:16, Vignesh Raman <vignesh.raman@xxxxxxxxxxxxx> wrote:
> >
> > Force db410c to host mode to fix network issue which results in failure
> > to mount root fs via NFS.
> > See https://gitlab.freedesktop.org/gfx-ci/linux/-/commit/cb72a629b8c15c80a54dda510743cefd1c4b65b8
> >
> > Use fdtoverlay command to merge base device tree with an overlay
> > which contains the fix for USB controllers to work in host mode.
> >
> > Signed-off-by: Vignesh Raman <vignesh.raman@xxxxxxxxxxxxx>
> > ---
> >
> > v2:
> >   - Use fdtoverlay command to merge overlay dtbo with the base dtb instead of modifying the kernel sources
> >
> > ---
> >  drivers/gpu/drm/ci/build.sh                         |  5 +++++
> >  .../gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dts  | 13 +++++++++++++
> >  2 files changed, 18 insertions(+)
> >  create mode 100644 drivers/gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dts
> >
> > diff --git a/drivers/gpu/drm/ci/build.sh b/drivers/gpu/drm/ci/build.sh
> > index 7b014287a041..92ffd98cd09e 100644
> > --- a/drivers/gpu/drm/ci/build.sh
> > +++ b/drivers/gpu/drm/ci/build.sh
> > @@ -92,6 +92,11 @@ done
> >
> >  if [[ -n ${DEVICE_TREES} ]]; then
> >      make dtbs
> > +    if [[ -e arch/arm64/boot/dts/qcom/apq8016-sbc.dtb ]]; then
> > +        dtc -@ -I dts -O dtb -o drivers/gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dtbo drivers/gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dts
> > +        fdtoverlay -i arch/arm64/boot/dts/qcom/apq8016-sbc.dtb -o arch/arm64/boot/dts/qcom/apq8016-sbc-overlay.dtb drivers/gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dtbo
> > +        mv arch/arm64/boot/dts/qcom/apq8016-sbc-overlay.dtb arch/arm64/boot/dts/qcom/apq8016-sbc.dtb
> > +    fi
> >      cp ${DEVICE_TREES} /lava-files/.
> >  fi
> >
> > diff --git a/drivers/gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dts b/drivers/gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dts
> > new file mode 100644
> > index 000000000000..57b7604f1c23
> > --- /dev/null
> > +++ b/drivers/gpu/drm/ci/dt-overlays/apq8016-sbc-overlay.dts
> > @@ -0,0 +1,13 @@
> > +/dts-v1/;
> > +/plugin/;
> > +
> > +/ {
> > +    fragment@0 {
> > +        target-path = "/soc@0";
> > +        __overlay__ {
> > +            usb@78d9000 {
> > +                dr_mode = "host";
> > +            };
> > +        };
> > +    };
> > +};
> > --
> > 2.40.1
> 
> Can we use normal dtso syntax here instead of defining fragments manually?

What Dmitry is hinting about is to use the "Sugar Syntax". There a good documentation here:
https://source.android.com/docs/core/architecture/dto/syntax

Maxime