Re: [PATCH] drm/sun4i: Use vi plane as primary

From: Roman Stratiienko
Date: Fri Sep 20 2019 - 03:54:51 EST


[ Resending message in plain mode ]

Hello guys,

Actually, I believe this is True solution, and current one is wrong.
Let me explain why.

De2. 0 was designed to match Android hwcomposer hal requirements IMO.
You can easily agree with this conclusion by comparing Composer HAL
and De2. 0 hardware manuals.

I faced at least 4 issues when trying to run Android using the
mainline kernel sun8i mixer implementation. Current one, missing pixel
formats (my previous patch), missing plane alpha and rotation
properties. I plan to fix it and also send appropriate solution to the
upstream.

To achieve optimal UI performance Android requires at least 4 ui
layers to make screen composition. Current patch enables 4th plane
usable.

As for using vi plane to display video. I assume that some of the
current users may have regression in their software, but it could be
easily fixed. For example if vi layer isn't fullscreen and should be
on top of the other layers, it can actually be placed on the bottom
and overlayed with pictures with transparent rectangles in video
region.
But I assume most of users such as browser etc. uses GPU for that.

And if you are watching fullscreen video, I can imagine only subtitles
layer and advertising layers on top of the video layers.


On Thu, Sep 19, 2019 at 9:15 PM Jernej Åkrabec <jernej.skrabec@xxxxxxxx> wrote:
>
> Dne Äetrtek, 19. september 2019 ob 19:17:54 CEST je Maxime Ripard napisal(a):
> > Hi,
> >
> > On Thu, Sep 19, 2019 at 03:37:03PM +0300, roman.stratiienko@xxxxxxxxxxxxxxx
> wrote:
> > > From: Roman Stratiienko <roman.stratiienko@xxxxxxxxxxxxxxx>
> > >
> > > DE2.0 blender does not take into the account alpha channel of vi layer.
> > > Thus makes overlaying of this layer totally opaque.
> > > Using vi layer as bottom solves this issue.
>
> What issue? Overlays don't have to be "full screen", thus missing support for
> alpha blending doesn't make it less valuable. And VI planes are already placed
> at the bottom (zpos = 0).
>
> > >
> > > Tested on Android.
> > >
> > > Signed-off-by: Roman Stratiienko <roman.stratiienko@xxxxxxxxxxxxxxx>
> >
> > It sounds like a workaround more than an actual fix.
> >
> > If the VI planes can't use the alpha, then we should just stop
> > reporting that format.
> >
> > Jernej, what do you think?
>
> Commit message is misleading. What this commit actually does is moving primary
> plane from first UI plane to bottom most plane, i.e. first VI plane. However, VI
> planes are scarce resource, almost all mixers have only one. I wouldn't set it
> as primary, because it's the only one which provide support for YUV formats.
> That could be used for example by video player for zero-copy rendering.
> Probably most apps wouldn't touch it if it was primary (that's usually
> reserved for window manager, if used).
>
> I left few formats with alpha channel exposed by VI planes, just because they
> don't have equivalent format without alpha. But I'm fine with removing them if
> you all agree on that.
>
> Best regards,
> Jernej
>
> >
> > Maxime
> >
> > > ---
> > >
> > > drivers/gpu/drm/sun4i/sun8i_ui_layer.c | 33 -----------------------
> > > drivers/gpu/drm/sun4i/sun8i_vi_layer.c | 36 +++++++++++++++++++++++++-
> > > 2 files changed, 35 insertions(+), 34 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/sun4i/sun8i_ui_layer.c
> > > b/drivers/gpu/drm/sun4i/sun8i_ui_layer.c index dd2a1c851939..25183badc85f
> > > 100644
> > > --- a/drivers/gpu/drm/sun4i/sun8i_ui_layer.c
> > > +++ b/drivers/gpu/drm/sun4i/sun8i_ui_layer.c
> > > @@ -99,36 +99,6 @@ static int sun8i_ui_layer_update_coord(struct
> > > sun8i_mixer *mixer, int channel,>
> > > insize = SUN8I_MIXER_SIZE(src_w, src_h);
> > > outsize = SUN8I_MIXER_SIZE(dst_w, dst_h);
> > >
> > > - if (plane->type == DRM_PLANE_TYPE_PRIMARY) {
> > > - bool interlaced = false;
> > > - u32 val;
> > > -
> > > - DRM_DEBUG_DRIVER("Primary layer, updating global size
> W: %u H: %u\n",
> > > - dst_w, dst_h);
> > > - regmap_write(mixer->engine.regs,
> > > - SUN8I_MIXER_GLOBAL_SIZE,
> > > - outsize);
> > > - regmap_write(mixer->engine.regs,
> > > - SUN8I_MIXER_BLEND_OUTSIZE(bld_base),
> outsize);
> > > -
> > > - if (state->crtc)
> > > - interlaced = state->crtc->state-
> >adjusted_mode.flags
> > > - & DRM_MODE_FLAG_INTERLACE;
> > > -
> > > - if (interlaced)
> > > - val = SUN8I_MIXER_BLEND_OUTCTL_INTERLACED;
> > > - else
> > > - val = 0;
> > > -
> > > - regmap_update_bits(mixer->engine.regs,
> > > -
> SUN8I_MIXER_BLEND_OUTCTL(bld_base),
> > > -
> SUN8I_MIXER_BLEND_OUTCTL_INTERLACED,
> > > - val);
> > > -
> > > - DRM_DEBUG_DRIVER("Switching display mixer interlaced
> mode %s\n",
> > > - interlaced ? "on" : "off");
> > > - }
> > > -
> > >
> > > /* Set height and width */
> > > DRM_DEBUG_DRIVER("Layer source offset X: %d Y: %d\n",
> > >
> > > state->src.x1 >> 16, state->src.y1 >> 16);
> > >
> > > @@ -349,9 +319,6 @@ struct sun8i_ui_layer *sun8i_ui_layer_init_one(struct
> > > drm_device *drm,>
> > > if (!layer)
> > >
> > > return ERR_PTR(-ENOMEM);
> > >
> > > - if (index == 0)
> > > - type = DRM_PLANE_TYPE_PRIMARY;
> > > -
> > >
> > > /* possible crtcs are set later */
> > > ret = drm_universal_plane_init(drm, &layer->plane, 0,
> > >
> > > &sun8i_ui_layer_funcs,
> > >
> > > diff --git a/drivers/gpu/drm/sun4i/sun8i_vi_layer.c
> > > b/drivers/gpu/drm/sun4i/sun8i_vi_layer.c index 07c27e6a4b77..49c4074e164f
> > > 100644
> > > --- a/drivers/gpu/drm/sun4i/sun8i_vi_layer.c
> > > +++ b/drivers/gpu/drm/sun4i/sun8i_vi_layer.c
> > > @@ -116,6 +116,36 @@ static int sun8i_vi_layer_update_coord(struct
> > > sun8i_mixer *mixer, int channel,>
> > > insize = SUN8I_MIXER_SIZE(src_w, src_h);
> > > outsize = SUN8I_MIXER_SIZE(dst_w, dst_h);
> > >
> > > + if (plane->type == DRM_PLANE_TYPE_PRIMARY) {
> > > + bool interlaced = false;
> > > + u32 val;
> > > +
> > > + DRM_DEBUG_DRIVER("Primary layer, updating global size
> W: %u H: %u\n",
> > > + dst_w, dst_h);
> > > + regmap_write(mixer->engine.regs,
> > > + SUN8I_MIXER_GLOBAL_SIZE,
> > > + outsize);
> > > + regmap_write(mixer->engine.regs,
> > > + SUN8I_MIXER_BLEND_OUTSIZE(bld_base),
> outsize);
> > > +
> > > + if (state->crtc)
> > > + interlaced = state->crtc->state-
> >adjusted_mode.flags
> > > + & DRM_MODE_FLAG_INTERLACE;
> > > +
> > > + if (interlaced)
> > > + val = SUN8I_MIXER_BLEND_OUTCTL_INTERLACED;
> > > + else
> > > + val = 0;
> > > +
> > > + regmap_update_bits(mixer->engine.regs,
> > > +
> SUN8I_MIXER_BLEND_OUTCTL(bld_base),
> > > +
> SUN8I_MIXER_BLEND_OUTCTL_INTERLACED,
> > > + val);
> > > +
> > > + DRM_DEBUG_DRIVER("Switching display mixer interlaced
> mode %s\n",
> > > + interlaced ? "on" : "off");
> > > + }
> > > +
> > >
> > > /* Set height and width */
> > > DRM_DEBUG_DRIVER("Layer source offset X: %d Y: %d\n",
> > >
> > > (state->src.x1 >> 16) & ~(format->hsub -
> 1),
> > >
> > > @@ -445,6 +475,7 @@ struct sun8i_vi_layer *sun8i_vi_layer_init_one(struct
> > > drm_device *drm,>
> > > struct
> sun8i_mixer *mixer,
> > > int index)
> > >
> > > {
> > >
> > > + enum drm_plane_type type = DRM_PLANE_TYPE_OVERLAY;
> > >
> > > struct sun8i_vi_layer *layer;
> > > unsigned int plane_cnt;
> > > int ret;
> > >
> > > @@ -453,12 +484,15 @@ struct sun8i_vi_layer
> > > *sun8i_vi_layer_init_one(struct drm_device *drm,>
> > > if (!layer)
> > >
> > > return ERR_PTR(-ENOMEM);
> > >
> > > + if (index == 0)
> > > + type = DRM_PLANE_TYPE_PRIMARY;
> > > +
> > >
> > > /* possible crtcs are set later */
> > > ret = drm_universal_plane_init(drm, &layer->plane, 0,
> > >
> > > &sun8i_vi_layer_funcs,
> > > sun8i_vi_layer_formats,
> > >
> ARRAY_SIZE(sun8i_vi_layer_formats),
> > >
> > > - NULL,
> DRM_PLANE_TYPE_OVERLAY, NULL);
> > > + NULL, type, NULL);
> > >
> > > if (ret) {
> > >
> > > dev_err(drm->dev, "Couldn't initialize layer\n");
> > > return ERR_PTR(ret);
> > >
> > > --
> > > 2.17.1
>
>
>
>


--
Best regards,
Roman Stratiienko
Global Logic
ADIT Team