On Wed, Nov 19, 2014 at 04:25:37PM +0200, Imre Deak wrote: > Currently after doing DPMS-OFF on all outputs CDCLK won't be set to its > minimum value as it should. A subsequent modeset to turn off all outputs > will thus run with all power domains disabled, and notice that it needs > to change CDCLK to its minimum value. Since the power domains are > disabled this will emit a register-access-while-suspended WARN and fail > to set the minimum freq. > > The proper solution for this is to set the minimum frequency during > DPMS-OFF. That needs a bigger rework that would take into account the > user DPMS setting too during the calculation of the new modesetting > configuration. Until that's done this stop-gap solution gets the PIPE-A > power domain during setting the CDCLK; this domain covers the HW blocks > needed for this. > > Idea to use PIPE-A domain from Ville. > > Testcase: igt/pm_rpm > Reference: https://bugs.freedesktop.org/show_bug.cgi?id=82939 > Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> Yeah, not exactly pretty but rearranging the DPMS code seems like a fairly sizeable task, so I think adding a kludge in the meantime is acceptable. Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/i915/intel_display.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c > index 9de2f69..6f29a72 100644 > --- a/drivers/gpu/drm/i915/intel_display.c > +++ b/drivers/gpu/drm/i915/intel_display.c > @@ -4939,10 +4939,23 @@ static void valleyview_modeset_global_resources(struct drm_device *dev) > int req_cdclk = valleyview_calc_cdclk(dev_priv, max_pixclk); > > if (req_cdclk != dev_priv->vlv_cdclk_freq) { > + /* > + * FIXME: We can end up here with all power domains off, yet > + * with a CDCLK frequency other than the minimum. To account > + * for this take the PIPE-A power domain, which covers the HW > + * blocks needed for the following programming. This can be > + * removed once it's guaranteed that we get here either with > + * the minimum CDCLK set, or the required power domains > + * enabled. > + */ > + intel_display_power_get(dev_priv, POWER_DOMAIN_PIPE_A); > + > if (IS_CHERRYVIEW(dev)) > cherryview_set_cdclk(dev, req_cdclk); > else > valleyview_set_cdclk(dev, req_cdclk); > + > + intel_display_power_put(dev_priv, POWER_DOMAIN_PIPE_A); > } > } > > -- > 1.8.4 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
