On Wed, Jun 25, 2014 at 10:34:48PM +0300, Ville Syrjälä wrote: > On Wed, Jun 25, 2014 at 11:55:58AM -0700, Jesse Barnes wrote: > > On Fri, 13 Jun 2014 13:37:53 +0300 > > ville.syrjala@xxxxxxxxxxxxxxx wrote: > > > > > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > > > > If someone is interested in the current cdclk frquency it should > > > be stable and not in process of changing frquency. Warn if the current > > > and requested cdclk don't match in .get_display_clock_spee() on vlv. > > > > > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > --- > > > drivers/gpu/drm/i915/intel_display.c | 4 ++++ > > > 1 file changed, 4 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c > > > index 29dddec..601e97e 100644 > > > --- a/drivers/gpu/drm/i915/intel_display.c > > > +++ b/drivers/gpu/drm/i915/intel_display.c > > > @@ -5234,6 +5234,10 @@ static int valleyview_get_display_clock_speed(struct drm_device *dev) > > > > > > divider = val & DISPLAY_FREQUENCY_VALUES; > > > > > > + WARN((val & DISPLAY_FREQUENCY_STATUS) != > > > + (divider << DISPLAY_FREQUENCY_STATUS_SHIFT), > > > + "cdclk change in progress\n"); > > > + > > > return DIV_ROUND_CLOSEST(vco << 1, divider + 1); > > > } > > > > > > > Hm, there's not much we can do in this case, so rather than warn maybe > > we should try a wait instead, and only warn if it times out? Even then > > there's not much we can do aside from poking the PUnit folks. > > This shouldn't happen unless we somehow messed up and triggered a cdclk > change and didn't wait for it to complete, which would be a driver bug. > So I think a simple WARN seems sufficient. I concur with Ville here so merged the patch. If we hit this we can figure out where exactly we've been wrong and whether there's a legitimate case where we need to wait for cdclk to settle. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
