Re: [PATCH v2 11/18] drm/sun4i: Add A83T support

[Jernej Åkrabec]

Hi,

Dne torek, 28. november 2017 ob 10:02:23 CET je Maxime Ripard napisal(a):
> Hi,
> 
> On Mon, Nov 27, 2017 at 05:01:49PM +0100, Jernej Åkrabec wrote:
> > Dne ponedeljek, 27. november 2017 ob 16:41:35 CET je Maxime Ripard 
napisal(a):
> > > Add support for the A83T display pipeline.
> > > 
> > > Reviewed-by: Chen-Yu Tsai <wens@xxxxxxxx>
> > > Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> > > ---
> > > 
> > >  Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt | 3 +++
> > >  drivers/gpu/drm/sun4i/sun4i_drv.c                             | 2 ++
> > >  drivers/gpu/drm/sun4i/sun4i_tcon.c                            | 5 +++++
> > >  drivers/gpu/drm/sun4i/sun8i_mixer.c                           | 4 ++++
> > >  4 files changed, 14 insertions(+)
> > > 
> > > diff --git
> > > a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> > > b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt index
> > > d4259a4f5171..d6b52e5c48c0 100644
> > > --- a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> > > +++ b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> > > 
> > > @@ -93,6 +93,7 @@ Required properties:
> > >     * allwinner,sun6i-a31s-tcon
> > >     * allwinner,sun7i-a20-tcon
> > >     * allwinner,sun8i-a33-tcon
> > > 
> > > +   * allwinner,sun8i-a83t-tcon-lcd
> > > 
> > >     * allwinner,sun8i-v3s-tcon
> > >   
> > >   - reg: base address and size of memory-mapped region
> > >   - interrupts: interrupt associated to this IP
> > > 
> > > @@ -224,6 +225,7 @@ supported.
> > > 
> > >  Required properties:
> > >    - compatible: value must be one of:
> > > +    * allwinner,sun8i-a83t-de2-mixer
> > 
> > What will be the name of the second mixer, once support for HDMI is added?
> > Should we start directly with 0 and 1 postfix ?
> 
> What are the differences exactly without the two mixers?

Mixer properties:
- mixer index (0 or 1), important for determining CCSC base (see my patches)
- number of VI planes (usually 1)
- number of UI planes (usually 1 or 3)
- writeback support (yes/no)
- scale line buffer length (2048 or 4096)
- smart backligth support (yes/no)

channel properties (for both, VI and UI):
- scaler support (yes/no, usually yes)
- overlay count (seems to be always 4)
- VEP support (yes/no)

Those are properties found in BSP de_feat.c, so I guess that's enough to make 
any kind of decision in the code.

Usually, but we can't count on that, first mixer has 1 VI and 3 UI planes and 
second mixer has 1 VI and 1 UI plane.

Best regards,
Jernej

> 
> I was hoping to be able to cover them all using properties, indices
> are usually pretty badly received in compatibles.
> 
> > >  static const struct of_device_id sun8i_mixer_of_table[] = {
> > >  
> > >  	{
> > > 
> > > +		.compatible = "allwinner,sun8i-a83t-de2-mixer",
> > > +		.data = &sun8i_v3s_mixer_cfg,
> > > +	},
> > > +	{
> > 
> > Maybe you want to squash 12 patch since this works only by luck.
> 
> Yeah, I totally meant to do that :)
> 
> Thanks!
> Maxime
> 
> --
> Maxime Ripard, Free Electrons
> Embedded Linux and Kernel engineering
> http://free-electrons.com