From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [Intel-gfx] [PATCH 3/3] drm/i915: Re-enable vblank irqs for already active pipes Date: Tue, 20 May 2014 19:31:33 +0200 Message-ID: <20140520173037.GA24095@phenom.ffwll.local> References: <1400595605-22938-1-git-send-email-ville.syrjala@linux.intel.com> <1400595605-22938-4-git-send-email-ville.syrjala@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <1400595605-22938-4-git-send-email-ville.syrjala@linux.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: ville.syrjala@linux.intel.com Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, May 20, 2014 at 05:20:05PM +0300, ville.syrjala@linux.intel.com wro= te: > From: Ville Syrj=E4l=E4 > = > If a pipe is already active when we init/resume there might not be a > full modeset afterwards so drm_vblank_on() may not get called. In such > a case if someone is holding a vblank reference across a suspend/resume > cycle drm_vblank_get() called after resuming won't re-enable the vblank > interrupts. > = > So in order to make sure vblank interrupts get re-enabled post-resume, > call drm_vblank_on() in intel_sanitize_crtc() if the crtc is already > active. > = > v2: Also drm_vblank_off() if the pipe got disabled magically > = > Signed-off-by: Ville Syrj=E4l=E4 This seems to duct-tape over the funny failure I'm seeing on my snb where kms_flip/vblank-vs-modeset|dpms-suspend work nicely, but kms_flip/vblank-vs-suspend has some totally hilarious random vblank frame counter after the modeset. Testecase: igt/kms_flip/vblank-vs-suspend Tested-by: Daniel Vetter Now the problem I have: We already call this in the crtc_enable hook. Why does calling this here again add the necessary magic? /me has no clue Cheers, Daniel > --- > drivers/gpu/drm/i915/intel_display.c | 6 ++++++ > 1 file changed, 6 insertions(+) > = > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/= intel_display.c > index 9420f4f..2e9f0b0 100644 > --- a/drivers/gpu/drm/i915/intel_display.c > +++ b/drivers/gpu/drm/i915/intel_display.c > @@ -11708,6 +11708,12 @@ static void intel_sanitize_crtc(struct intel_crt= c *crtc) > reg =3D PIPECONF(crtc->config.cpu_transcoder); > I915_WRITE(reg, I915_READ(reg) & ~PIPECONF_FRAME_START_DELAY_MASK); > = > + /* restore vblank interrupts to correct state */ > + if (crtc->active) > + drm_vblank_on(dev, crtc->pipe); > + else > + drm_vblank_off(dev, crtc->pipe); > + > /* We need to sanitize the plane -> pipe mapping first because this will > * disable the crtc (and hence change the state) if it is wrong. Note > * that gen4+ has a fixed plane -> pipe mapping. */ > -- = > 1.8.5.5 > = > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- = Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch