[Intel-gfx] [PATCH 31/67] drm/i915/cnl: Allow dynamic cdclk changes on CNL
Rodrigo Vivi
rodrigo.vivi at gmail.com
Tue Jun 6 15:24:51 UTC 2017
On Mon, Jun 5, 2017 at 10:04 AM, Pandiyan, Dhinakaran
<dhinakaran.pandiyan at intel.com> 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 at linux.intel.com>
>> > > > Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
>> > > > ---
>> > > > 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 at lists.freedesktop.org
>> > > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>> >
>>
>
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Rodrigo Vivi
Blog: http://blog.vivi.eng.br
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