On Mon, Sep 28, 2020 at 04:07:39PM -0700, Lucas De Marchi wrote:
> On Mon, Sep 28, 2020 at 08:15:29PM +0300, Jani Nikula wrote:
> > On Mon, 28 Sep 2020, "Surendrakumar Upadhyay, TejaskumarX" <[email protected]> wrote:
> > > This is a good example of a potential trap that having
> > > IS_ELKHARTLAKE() cover both ELK and JSP creates. An unsuspecting coder
> > > might change the if ladder to have IS_ELKHARTLAKE() first, and the
> > > subsequent IS_JASPERLAKE() branch would never be taken.
> > >
> > > BR,
> > > Jani.
> > >
> > > Tejas : In that case I will put attention note in comment about
> > > platform checks such that ladder distrubance can be avoided. What you
> > > suggest?
>
> > The solution is to make IS_ELKHARTLAKE() mean ELK and only ELK.
>
> Since we are talking about the TLA for JSL in the other patch, for
> elkhartlake it is EHL, not ELK. ELK is something else, but I'm not sure
> what:
>
> $ git grep -w ELK -- drivers/gpu/drm/
> drivers/gpu/drm/i915/gem/i915_gem_stolen.c: IS_GM45(i915) ? "CTG" : "ELK", reg_val);
> drivers/gpu/drm/i915/gem/i915_gem_stolen.c: * Whether ILK really reuses the ELK register for this is unclear.
> drivers/gpu/drm/i915/intel_pm.c: * Not 100% sure which way ELK should go here as the
> drivers/gpu/drm/i915/intel_pm.c: * assume ELK doesn't need this.
Yeah, ELK = Eagle Lake, CTG = Cantiga. Both are old gen5 platforms IIRC.
Matt
>
> Lucas De Marchi
>
> >
> > BR,
> > Jani.
> >
> >
> > --
> > Jani Nikula, Intel Open Source Graphics Center
--
Matt Roper
Graphics Software Engineer
VTT-OSGC Platform Enablement
Intel Corporation
(916) 356-2795
On Mon, 28 Sep 2020, Matt Roper <[email protected]> wrote:
> On Mon, Sep 28, 2020 at 04:07:39PM -0700, Lucas De Marchi wrote:
>> On Mon, Sep 28, 2020 at 08:15:29PM +0300, Jani Nikula wrote:
>> > On Mon, 28 Sep 2020, "Surendrakumar Upadhyay, TejaskumarX" <[email protected]> wrote:
>> > > This is a good example of a potential trap that having
>> > > IS_ELKHARTLAKE() cover both ELK and JSP creates. An unsuspecting coder
>> > > might change the if ladder to have IS_ELKHARTLAKE() first, and the
>> > > subsequent IS_JASPERLAKE() branch would never be taken.
>> > >
>> > > BR,
>> > > Jani.
>> > >
>> > > Tejas : In that case I will put attention note in comment about
>> > > platform checks such that ladder distrubance can be avoided. What you
>> > > suggest?
>>
>> > The solution is to make IS_ELKHARTLAKE() mean ELK and only ELK.
>>
>> Since we are talking about the TLA for JSL in the other patch, for
>> elkhartlake it is EHL, not ELK. ELK is something else, but I'm not sure
>> what:
>>
>> $ git grep -w ELK -- drivers/gpu/drm/
>> drivers/gpu/drm/i915/gem/i915_gem_stolen.c: IS_GM45(i915) ? "CTG" : "ELK", reg_val);
>> drivers/gpu/drm/i915/gem/i915_gem_stolen.c: * Whether ILK really reuses the ELK register for this is unclear.
>> drivers/gpu/drm/i915/intel_pm.c: * Not 100% sure which way ELK should go here as the
>> drivers/gpu/drm/i915/intel_pm.c: * assume ELK doesn't need this.
>
> Yeah, ELK = Eagle Lake, CTG = Cantiga. Both are old gen5 platforms IIRC.
Yeah, I know, my bad.
BR,
Jani.
>
>
> Matt
>
>>
>> Lucas De Marchi
>>
>> >
>> > BR,
>> > Jani.
>> >
>> >
>> > --
>> > Jani Nikula, Intel Open Source Graphics Center
--
Jani Nikula, Intel Open Source Graphics Center