Re: [PATCH 31/67] drm/i915/cnl: Allow dynamic cdclk changes on CNL

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Jun 5, 2017 at 10:04 AM, Pandiyan, Dhinakaran
<dhinakaran.pandiyan@xxxxxxxxx> wrote:
> On Mon, 2017-06-05 at 19:55 +0300, Ville Syrjälä wrote:
>> On Mon, Jun 05, 2017 at 04:41:07PM +0000, Vivi, Rodrigo wrote:
>> > On Mon, 2017-06-05 at 18:22 +0300, Imre Deak wrote:
>> > > On Thu, Apr 06, 2017 at 12:15:27PM -0700, Rodrigo Vivi wrote:
>> > > > All the low level cdclk bits are present, so let's add the required
>> > > > hooks to reconfigure cdclk on the fly.
>> > > >
>> > > > v2: Rebase due to cnl_sanitize_cdclk()
>> > > > v3: Rebased by Rodrigo on top of Ville's cdclk rework.
>> > > > v4: Rebase moving cnl_calc_cdclk up to follow same order
>> > > >     as previous platforms.
>> > > >
>> > > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>> > > > Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
>> > > > ---
>> > > >  drivers/gpu/drm/i915/intel_cdclk.c | 54 ++++++++++++++++++++++++++++++++++++--
>> > > >  1 file changed, 52 insertions(+), 2 deletions(-)
>> > > >
>> > > > diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c
>> > > > index f9ba1e7..a8c254b 100644
>> > > > --- a/drivers/gpu/drm/i915/intel_cdclk.c
>> > > > +++ b/drivers/gpu/drm/i915/intel_cdclk.c
>> > > > @@ -1400,6 +1400,16 @@ void bxt_uninit_cdclk(struct drm_i915_private *dev_priv)
>> > > >         bxt_set_cdclk(dev_priv, &cdclk_state);
>> > > >  }
>> > > >
>> > > > +static int cnl_calc_cdclk(int max_pixclk)
>> > > > +{
>> > > > +       if (max_pixclk > 336000)
>> > > > +               return 528000;
>> > > > +       else if (max_pixclk > 168000)
>> > > > +               return 336000;
>> > > > +       else
>> > > > +               return 168000;
>> > > > +}
>> > > > +
>> > > >  static void cnl_cdclk_pll_update(struct drm_i915_private *dev_priv,
>> > > >                                  struct intel_cdclk_state *cdclk_state)
>> > > >  {
>> > > > @@ -1640,7 +1650,7 @@ void cnl_init_cdclk(struct drm_i915_private *dev_priv)
>> > > >
>> > > >         cdclk_state = dev_priv->cdclk.hw;
>> > > >
>> > > > -       cdclk_state.cdclk = 168000;
>> > > > +       cdclk_state.cdclk = cnl_calc_cdclk(0);
>> > > >         cdclk_state.vco = cnl_cdclk_pll_vco(dev_priv, cdclk_state.cdclk);
>> > > >
>> > > >         cnl_set_cdclk(dev_priv, &cdclk_state);
>> > > > @@ -1928,6 +1938,40 @@ static int bxt_modeset_calc_cdclk(struct drm_atomic_state *state)
>> > > >         return 0;
>> > > >  }
>> > > >
>> > > > +static int cnl_modeset_calc_cdclk(struct drm_atomic_state *state)
>> > > > +{
>> > > > +       struct drm_i915_private *dev_priv = to_i915(state->dev);
>> > > > +       struct intel_atomic_state *intel_state =
>> > > > +               to_intel_atomic_state(state);
>> > > > +       int max_pixclk = intel_max_pixel_rate(state);
>> > > > +       int cdclk, vco;
>> > > > +
>> > > > +       cdclk = cnl_calc_cdclk(max_pixclk);
>> > > > +       vco = cnl_cdclk_pll_vco(dev_priv, cdclk);
>> > >
>> > > The spec says not to set CDCLK to 168MHz if audio is used with 96MHz
>> > > BCLK, what's the plan to add that constraint? At least there could be a
>> > > TODO: here.
>> >
>> > That's a good question.
>> > Do we have ways to know the audio freq?
>> > Or we need to add few extra hooks?
>> > And agree, at least a TODO or FIXME here is needed while we dont have a
>> > clear path.
>>
>> bdw_adjust_min_pipe_pixel_rate() just assumes 96MHz. There was some
>> discussion on the topic, and I found some register that possibly could
>> tell us something. But the best solution would probably involve querying
>> it from the audio driver.
>>
>
> The last time I checked with the audio folks, the driver does not change
> the BCLK freq. and the default is 96 MHz.

So, what should we do for now? Block 168? Remove 168?

>
>
>> >
>> > >
>> > > > +
>> > > > +       if (cdclk > dev_priv->max_cdclk_freq) {
>> > > > +               DRM_DEBUG_KMS("requested cdclk (%d kHz) exceeds max (%d kHz)\n",
>> > > > +                             cdclk, dev_priv->max_cdclk_freq);
>> > > > +               return -EINVAL;
>> > > > +       }
>> > > > +
>> > > > +       intel_state->cdclk.logical.vco = vco;
>> > > > +       intel_state->cdclk.logical.cdclk = cdclk;
>> > > > +
>> > > > +       if (!intel_state->active_crtcs) {
>> > > > +               cdclk = cnl_calc_cdclk(0);
>> > > > +               vco = cnl_cdclk_pll_vco(dev_priv, cdclk);
>> > > > +
>> > > > +               intel_state->cdclk.actual.vco = vco;
>> > > > +               intel_state->cdclk.actual.cdclk = cdclk;
>> > > > +       } else {
>> > > > +               intel_state->cdclk.actual =
>> > > > +                       intel_state->cdclk.logical;
>> > > > +       }
>> > > > +
>> > > > +       return 0;
>> > > > +}
>> > > > +
>> > > >  static int intel_compute_max_dotclk(struct drm_i915_private *dev_priv)
>> > > >  {
>> > > >         int max_cdclk_freq = dev_priv->max_cdclk_freq;
>> > > > @@ -1959,7 +2003,9 @@ static int intel_compute_max_dotclk(struct drm_i915_private *dev_priv)
>> > > >   */
>> > > >  void intel_update_max_cdclk(struct drm_i915_private *dev_priv)
>> > > >  {
>> > > > -       if (IS_GEN9_BC(dev_priv)) {
>> > > > +       if (IS_CANNONLAKE(dev_priv)) {
>> > > > +               dev_priv->max_cdclk_freq = 528000;
>> > > > +       } else if (IS_GEN9_BC(dev_priv)) {
>> > > >                 u32 limit = I915_READ(SKL_DFSM) & SKL_DFSM_CDCLK_LIMIT_MASK;
>> > > >                 int max_cdclk, vco;
>> > > >
>> > > > @@ -2158,6 +2204,10 @@ void intel_init_cdclk_hooks(struct drm_i915_private *dev_priv)
>> > > >                 dev_priv->display.set_cdclk = skl_set_cdclk;
>> > > >                 dev_priv->display.modeset_calc_cdclk =
>> > > >                         skl_modeset_calc_cdclk;
>> > > > +       } else if (IS_CANNONLAKE(dev_priv)) {
>> > > > +               dev_priv->display.set_cdclk = cnl_set_cdclk;
>> > > > +               dev_priv->display.modeset_calc_cdclk =
>> > > > +                       cnl_modeset_calc_cdclk;
>> > > >         }
>> > > >
>> > > >         if (IS_CANNONLAKE(dev_priv))
>> > > > --
>> > > > 1.9.1
>> > > >
>> > > > _______________________________________________
>> > > > Intel-gfx mailing list
>> > > > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
>> > > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>> >
>>
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx



-- 
Rodrigo Vivi
Blog: http://blog.vivi.eng.br
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]
  Powered by Linux