[PATCH v2 22/22] drm: mxsfb: Support the alpha plane

[Laurent Pinchart]

Hi Emil,

On Sun, May 31, 2020 at 05:54:04PM +0100, Emil Velikov wrote:
> HI Laurent,
> 
> From a quick glance the series looks really good and neat.

Thank you :-)

> Then again, I don't know much about the hardware to provide meaningful
> review.
>
> A couple of small ideas below.
> 
> On Sat, 30 May 2020 at 04:11, Laurent Pinchart wrote:
> 
> > +#define LCDC_AS_BUF                    0x220
> > +#define LCDC_AS_NEXT_BUF               0x230
> 
> s/LCDC_AS_BUF/LCDC_AS_CUR_BUF/ - to stay consistent with the primary
> plane name scheme.

The register names come directly from the datasheet (and yes, the
datasheet uses CUR_BUF and NEXT_BUF for the primary plane, and BUF and
NEXT_BUF for the overlay plane :-S). I'd thus rather keep them aligned
with the documentation.

> Would it make sense to store the above registers in mxsfb_devdata,
> just like we do for the primary planes?

The reason the register addresses are stored in mxsfb_devdata for the
primary plane is because they differ between hardware revisions (don't
they teach hardware engineers in school these days *not* to move
registers around ? :-)). The overlay plane is only supported in the
latest versions of the IP core, and are always located at the same
address as far as I can tell. I don't think we need an extra level of
indirection.

-- 
Regards,

Laurent Pinchart