Re: [PATCH 03/21] drm/msm/dsi: pass the right width to dsc

[Dmitry Baryshkov]

On Tue, 3 Sept 2024 at 10:34, Jun Nie <jun.nie@xxxxxxxxxx> wrote:
>
> Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> 于2024年8月29日周四 18:57写道：
> >
> > On Thu, 29 Aug 2024 at 13:19, Jun Nie <jun.nie@xxxxxxxxxx> wrote:
> > >
> > > Data width for dsc engine is aligned with pipe, not with whole screen
> > > width. Because the width may be halved in DSI bonded case.
> >
> > Can't really parse this.
>
> Please forgive me for my bad English. Is below words better?
>
> Data width for DSC timing is aligned with the width that goes to a DSI

to a single DSI interface

> interface, not with whole screen width. For bonded-DSI case, the
> width for DSC timing is half width of whole screen.

sounds much better.

> >
> > >
> > > The dsc width is not related to the timing with back front porch in
> > > later stage, so update dsc timing earlier.
> > >
> > > Signed-off-by: Jun Nie <jun.nie@xxxxxxxxxx>
> > > ---
> > >  drivers/gpu/drm/msm/dsi/dsi_host.c | 13 ++++++-------
> > >  1 file changed, 6 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > > index 7a4d9c071be5a..5abade8f26b88 100644
> > > --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> > > +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > > @@ -953,7 +953,7 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
> > >                         return;
> > >                 }
> > >
> > > -               dsc->pic_width = mode->hdisplay;
> > > +               dsc->pic_width = hdisplay;
> > >                 dsc->pic_height = mode->vdisplay;
> > >                 DBG("Mode %dx%d\n", dsc->pic_width, dsc->pic_height);
> >
> > Two separate commits
>
> OK. Will split it.
>
> >
> > >
> > > @@ -964,6 +964,11 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
> > >                 if (ret)
> > >                         return;
> > >
> > > +               if (msm_host->mode_flags & MIPI_DSI_MODE_VIDEO)
> > > +                       dsi_update_dsc_timing(msm_host, false, hdisplay);
> > > +               else
> > > +                       dsi_update_dsc_timing(msm_host, true, hdisplay);
> > > +
> > >                 /*
> > >                  * DPU sends 3 bytes per pclk cycle to DSI. If widebus is
> > >                  * enabled, bus width is extended to 6 bytes.
> > > @@ -990,9 +995,6 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
> > >         }
> > >
> > >         if (msm_host->mode_flags & MIPI_DSI_MODE_VIDEO) {
> > > -               if (msm_host->dsc)
> > > -                       dsi_update_dsc_timing(msm_host, false, mode->hdisplay);
> > > -
> > >                 dsi_write(msm_host, REG_DSI_ACTIVE_H,
> > >                         DSI_ACTIVE_H_START(ha_start) |
> > >                         DSI_ACTIVE_H_END(ha_end));
> > > @@ -1011,9 +1013,6 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
> > >                         DSI_ACTIVE_VSYNC_VPOS_START(vs_start) |
> > >                         DSI_ACTIVE_VSYNC_VPOS_END(vs_end));
> > >         } else {                /* command mode */
> > > -               if (msm_host->dsc)
> > > -                       dsi_update_dsc_timing(msm_host, true, mode->hdisplay);
> > > -
> > >                 /* image data and 1 byte write_memory_start cmd */
> > >                 if (!msm_host->dsc)
> > >                         wc = hdisplay * mipi_dsi_pixel_format_to_bpp(msm_host->format) / 8 + 1;
> > >
> > > --
> > > 2.34.1
> > >
> >
> >
> > --
> > With best wishes
> > Dmitry



-- 
With best wishes
Dmitry