Re: [PATCH v2 3/4] drm/msm/dpu: Add DPU_INTF_DATA_COMPRESS feature flag

[Dmitry Baryshkov]

On 09/05/2023 03:28, Abhinav Kumar wrote:
> On 5/8/2023 4:08 PM, Dmitry Baryshkov wrote:
> > On 09/05/2023 00:46, Jessica Zhang wrote:
> > > On 5/7/2023 9:00 AM, Marijn Suijten wrote:
> > > > On 2023-05-05 14:23:50, Jessica Zhang wrote:
> > > > > Add DATA_COMPRESS feature flag to DPU INTF block.
> > > > >
> > > > > In DPU 7.x and later, DSC/DCE enablement registers have been moved 
> > > > > from
> > > > > PINGPONG to INTF.
> > > > >
> > > > > As core_rev (and related macros) was removed from the dpu_kms 
> > > > > struct, the
> > > > > most straightforward way to indicate the presence of this register 
> > > > > would be
> > > > > to have a feature flag.
> > > >
> > > > Irrelevant.  Even though core_rev was still in mainline until recently,
> > > > we always hardcoded the features in the catalog and only used core_rev
> > > > to select a dpu_mdss_cfg catalog entry.  There is no "if version >= X
> > > > then enable feature Y" logic, this manually-enabled feature flag is the
> > > > only, correct way to do it.
> > >
> > > Hi Marijn,
> > >
> > > Understood. FWIW, if we do find more register bit-level differences 
> > > between HW versions in the future, it might make more sense to keep 
> > > the HW catalog small and bring core_rev back, rather than keep adding 
> > > these kinds of small differences to caps.
> >
> > Let's see how it goes. Abhinav suggested that there might be feature 
> > differences inside the DPU generations (and even inside the single DPU 
> > major/minor combo). So I'm not sure what core_rev will bring us.
>
> It allows us to have if MDSS_REV() checks which are convenient for some 
> calculations / bit programming which we dont want to expose in the 
> catalog as they cannot be classified as a hw cap as such or atleast we 
> dont want them to be classified as such.
>
> > Let's land the platforms which are ready (or if there is anything 
> > close to be submitted). I'll post the next proposal for the catalog 
> > cleanups close to -rc4, when the dust settles then we can have one or 
> > two weaks for the discussion and polishing.
> >
> > I'd like to consider:
> > - inlining foo_BLK macros, if that makes adding new features easier
> > - reformat of clk_ctrls
> > - maybe reintroduction of per-generation feature masks instead of 
> > keeping them named after the random SoC
> > - maybe a rework of mdss_irqs / INTFn_INTR. We already have this info 
> > in hw catalog.
> >
> > Comments are appreciated.
>
> I would say, lets wait for DSC to settle. Atleast the parts already on 
> the list. Continuous rebase of features already on the list is becoming 
> time consuming because of overlapping catalog reworks.

As I wrote, -rc4. Until that time, I'd expect DSC to be settled and 
accepted.

--
With best wishes
Dmitry