[Intel-gfx] [RFC 4/8] drm/i915: Group gen 10 display.

[Ville Syrjälä]

On Fri, Oct 19, 2018 at 09:41:37AM -0700, Rodrigo Vivi wrote:
> On Fri, Oct 19, 2018 at 01:33:08PM +0300, Ville Syrjälä wrote:
> > On Fri, Oct 19, 2018 at 10:30:46AM +0200, Daniel Vetter wrote:
> > > On Fri, Oct 19, 2018 at 11:03:53AM +0300, Jani Nikula wrote:
> > > > On Thu, 18 Oct 2018, Rodrigo Vivi <rodrigo.vivi at intel.com> wrote:
> > > > > Continuing with the goal of use less platform codenames:
> > > > > let's group platforms who has gen10 display.
> > > > 
> > > > Ahah, so this answers my question in the previous patch. ;)
> > > > 
> > > > So we already have HAS_GMCH_DISPLAY().
> > > 
> > > We also have HAS_DDI, which I guess you could call gen8 display :-)
> > 
> > There's also these interesting gen designations in some old docs:
> > ctg/elk = gen5.5
> > ilk = gen5.75
> > I guess we could more or less call all of that as gen5 display.
> > 
> > And of course we have the other oddballs like vlv/chv which are
> > sort of mismash of i965, ctg/elk, ibx, and custom stuff. Also
> > pnv is mostly gen3 display except for a few bits that were
> > snatched from i965.
> > 
> > Not sure we have enough numbers for all that without resotring to
> > fractions. And no one could anyway remember what all the different
> > numbers mean.
> 
> Thanks for all the comments. Yeap, the idea is not to use this series
> as is but just start the discussion and evolve it.
> 
> Gen number by itself doesn't fit to display indeed, but neither
> display-gen-number because we have the fraction and cases like glk
> that is gen10-stripped-display+bxt :/
> 
> Also platform names are not enough by itself, like cannnonlake-with-port-f
> because the sku lacks on having a different name. If you take a look to our
> internal branch the same is about to happen with icl soon....
> 
> So my idea was that we first use feature {name, or number of something}
> whenever possible. On the secondary case we use groups of things like
> HAS_GMCH_DISPLAY, HAS_GEN10_DISPLAY, HAS_VLV_DISPLAY. And on last case
> we use gen numbers.
> 
> My idea of preferring gen over platform names in general was that for
> platform name we cannot use >= ICELAKE... :/

Well... we could. Assuming we order the enum suitably. Problem
is that there may not be a single order that works for all cases.
But it might be good enough for a lot of the cases.

-- 
Ville Syrjälä
Intel