On Tue, 10 Jun 2014, Daniel Vetter <daniel@xxxxxxxx> wrote: > On Mon, Jun 09, 2014 at 10:06:29PM +0300, Jani Nikula wrote: >> On Mon, 09 Jun 2014, Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> wrote: >> > On Mon, Jun 09, 2014 at 09:12:18PM +0300, Jani Nikula wrote: >> >> On Fri, 06 Jun 2014, Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: >> >> > It causes black screen on bootup and is approximately 100x slower than >> >> > running with FBC disabled, so the GPU runs at a high frequency for much >> >> > longer - completely contrary to the power saving claims. It also still >> >> > has mutex deadlocks in multi-head scenarios, which can lead to a >> >> > system/X lockup. These bugs were known before FBC was enabled by default >> >> > on Haswell and still have not been fixed. >> >> > >> >> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79716 >> >> > Reported-and-tested-by: Jon Kristensen <info@xxxxxxxxxx> >> >> > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> >> >> > Cc: stable@xxxxxxxxxxxxxxx >> >> > --- >> >> > drivers/gpu/drm/i915/intel_pm.c | 3 +-- >> >> > 1 file changed, 1 insertion(+), 2 deletions(-) >> >> > >> >> > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c >> >> > index e403010540a5..0b8a6010427e 100644 >> >> > --- a/drivers/gpu/drm/i915/intel_pm.c >> >> > +++ b/drivers/gpu/drm/i915/intel_pm.c >> >> > @@ -511,8 +511,7 @@ void intel_update_fbc(struct drm_device *dev) >> >> > obj = intel_fb->obj; >> >> > adjusted_mode = &intel_crtc->config.adjusted_mode; >> >> > >> >> > - if (i915.enable_fbc < 0 && >> >> > - INTEL_INFO(dev)->gen <= 7 && !IS_HASWELL(dev)) { >> >> > + if (i915.enable_fbc < 0) { >> >> >> >> Not only does this disable FBC by default on Haswell but also on all >> >> current and future platforms, including Broadwell. Shouldn't you leave >> >> the INTEL_INFO(dev)->gen <= 7 part intact? >> > >> > The current FBC code is universally broken. >> >> Well, then the commit message should reflect that! :p > > s/Haswell/Haswell+/ and it's correct ;-) Pushed to -fixes with a little more verbose change. Thanks for the patch and review. BR, Jani. > -Daniel > -- > Daniel Vetter > Software Engineer, Intel Corporation > +41 (0) 79 365 57 48 - http://blog.ffwll.ch -- Jani Nikula, Intel Open Source Technology Center -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html