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Date:   Sun, 25 Jun 2023 19:56:51 +0300
From:   Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Magnus Damm <magnus.damm@gmail.com>,
        dri-devel@lists.freedesktop.org, linux-renesas-soc@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 24/39] drm: renesas: shmobile: Unify plane allocation
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On Sun, Jun 25, 2023 at 10:58:17AM +0200, Geert Uytterhoeven wrote:
> On Fri, Jun 23, 2023 at 8:50 PM Laurent Pinchart wrote:
> > On Fri, Jun 23, 2023 at 07:55:22PM +0200, Geert Uytterhoeven wrote:
> > > On Fri, Jun 23, 2023 at 6:50 PM Laurent Pinchart wrote:
> > > > On Thu, Jun 22, 2023 at 11:21:36AM +0200, Geert Uytterhoeven wrote:
> > > > > Unify primary and overlay plane allocation:
> > > > >   - Enhance shmob_drm_plane_create() so it can be used to create the
> > > > >     primary plane, too,
> > > > >   - Move overlay plane creation next to primary plane creation.
> > > > >
> > > > > As overlay plane index zero now means the primary plane, this requires
> > > > > shifting all overlay plane indices by one.
> > > >
> > > > Do you use index zero to identify the primary plane just for
> > > > shmob_drm_plane_create(), or somewhere else too ? If it's just to create
> > > > the plane, you could instead pass the plane type to the function.
> > >
> > > Index zero is just used for the creation.
> > > I guess this sort of goes together with my question below...
> > >
> > > > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > > > > ---
> > > > > Perhaps it would be better to not use dynamic allocation, but store
> > > > > "struct drm_plane primary" and "struct shmob_drm_plane planes[5]" in
> > > > > struct drm_shmob_device instead, like is done for the crtc and encoder?
> > >
> > > ... as embedding separate primary and planes[] would also get rid of
> > > the need to adjust the plane indices when converting from logical to physical
> > > overlay plane indices.
> >
> > Do they need to be embedded for that, or could you simple keep the index
> > as it is ?
> 
> If the plane type would be passed explicitly, they would not need to be
> embedded for that.
> 
> Then the question becomes: does it make sense to unify primary and
> overlay plane handling?

Good point. I don't mind much either way, it depends on how much code
duplication it would remove I suppose.

-- 
Regards,

Laurent Pinchart