On to, 2015-11-12 at 10:14 -0800, Bob Paauwe wrote: > On Thu, 12 Nov 2015 10:35:00 +0200 > Imre Deak <imre.deak@xxxxxxxxx> wrote: > > > On Wed, 2015-11-11 at 13:36 -0800, Bob Paauwe wrote: > > > On Tue, 10 Nov 2015 11:04:22 +0200 > > > Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx> wrote: > > > > > > > Bob Paauwe <bob.j.paauwe@xxxxxxxxx> writes: > > > > > > > > > Signed-off-by: Bob Paauwe <bob.j.paauwe@xxxxxxxxx> > > > > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92768 > > > > > --- > > > > > drivers/gpu/drm/i915/intel_pm.c | 4 ++-- > > > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > > > > > diff --git a/drivers/gpu/drm/i915/intel_pm.c > > > > > b/drivers/gpu/drm/i915/intel_pm.c > > > > > index 647c0ff..fc5097f 100644 > > > > > --- a/drivers/gpu/drm/i915/intel_pm.c > > > > > +++ b/drivers/gpu/drm/i915/intel_pm.c > > > > > @@ -7138,7 +7138,7 @@ static int chv_freq_opcode(struct > > > > > drm_i915_private *dev_priv, int val) > > > > > > > > > > int intel_gpu_freq(struct drm_i915_private *dev_priv, int > > > > > val) > > > > > { > > > > > - if (IS_GEN9(dev_priv->dev)) > > > > > + if (IS_GEN9(dev_priv->dev) && !IS_BROXTON(dev_priv > > > > > ->dev)) > > > > > return (val * GT_FREQUENCY_MULTIPLIER) / > > > > > GEN9_FREQ_SCALER; > > > > > > > > Documentation disagrees with this patch. The units are 16.67Mhz > > > > thus we should use 50/3. > > > > > > > > -Mika > > > > > > I'm not sure I trust the documentation in this case. Elsewhere, > > > in > > > gen6_init_rps_frequencies() we use GEN9_FREQ_SCALER for SKL only, > > > not for BXT. > > > > On SKL the frequency _capability_ register uses 50MHz units, but > > the > > frequency _request_ register uses 16.67MHz units. We store the > > frequency > > limits in 16.67MHz units in rps.rp*_freq, hence the use of > > GEN9_FREQ_SCALER in gen6_init_rps_frequencies(). When requesting a > > frequency we only use GEN9_FREQ_SCALER to get the 16.67MHz constant > > value. > > > > On BXT both the capability and request registers use 16.67MHz > > units, so > > we don't need to convert in gen6_init_rps_frequencies(), but we > > still > > use GEN9_FREQ_SCALER when requesting the frequency to get the > > 16.67MHz > > constant value. > > Confusing like hell, but it works. > > That makes it a bit less confusing, thanks! Is this all documented > somewhere? I'd like to read up on it so if you have any pointers > please send me an email. For SKL: RP_STATE_CAP in configdb (offset 0x5998) RP_FREQ_NORMAL in bspec (0xA008) For BXT: GRAPHICS_FREQUENCY_CAPABILITIES in configdb (offset 0x8170) RP_FREQ_NORMAL in bspec (0xA008) --Imre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
