[Intel-gfx] [PATCH] drm/i915/slpc: Fix PCODE IA Freq requests when using SLPC

[Dixit, Ashutosh]

On Fri, 26 Aug 2022 13:03:05 -0700, Dixit, Ashutosh wrote:
>
> On Fri, 26 Aug 2022 10:44:34 -0700, Rodrigo Vivi wrote:
> >
> > Fixes: 7ba79a671568 ("drm/i915/guc/slpc: Gate Host RPS when SLPC is enabled")
> > Cc: <stable at vger.kernel.org> # v5.15+
> > Cc: Ashutosh Dixit <ashutosh.dixit at intel.com>
> > Tested-by: Sushma Venkatesh Reddy <sushma.venkatesh.reddy at intel.com>
> > Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > ---
> >  drivers/gpu/drm/i915/gt/intel_llc.c | 24 ++++++++++++++++--------
> >  1 file changed, 16 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/gt/intel_llc.c b/drivers/gpu/drm/i915/gt/intel_llc.c
> > index 14fe65812e42..2677d62573d9 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_llc.c
> > +++ b/drivers/gpu/drm/i915/gt/intel_llc.c
> > @@ -49,13 +49,28 @@ static unsigned int cpu_max_MHz(void)
> >  static bool get_ia_constants(struct intel_llc *llc,
> >			     struct ia_constants *consts)
> >  {
> > +	struct intel_guc_slpc *slpc = &llc_to_gt(llc)->uc.guc.slpc;
> >	struct drm_i915_private *i915 = llc_to_gt(llc)->i915;
> >	struct intel_rps *rps = &llc_to_gt(llc)->rps;
> >
> >	if (!HAS_LLC(i915) || IS_DGFX(i915))
> >		return false;
> >
> > -	if (rps->max_freq <= rps->min_freq)
> > +	if (intel_uc_uses_guc_slpc(&llc_to_gt(llc)->uc)) {
> > +		consts->min_gpu_freq = slpc->min_freq;
> > +		consts->max_gpu_freq = slpc->rp0_freq;

Sorry, this also doesn't work because slpc freq are converted using
intel_gpu_freq(). How about calling gen6_rps_get_freq_caps() directly in
the SLPC case? Or we could go with the original patch for now with a FIXME?
Thanks.

> > +	} else {
> > +		consts->min_gpu_freq = rps->min_freq;
> > +		consts->max_gpu_freq = rps->max_freq;
> > +	}
> > +
> > +	if (GRAPHICS_VER(i915) >= 9) {
> > +		/* Convert GT frequency to 50 HZ units */
> > +		consts->min_gpu_freq /= GEN9_FREQ_SCALER;
> > +		consts->max_gpu_freq /= GEN9_FREQ_SCALER;
> > +	}