Re: [Intel-gfx] [PATCH 1/2] drm/i915: Restore lost DPLL register write on gen2-4
On Tue, 13 Oct 2015, Daniel Vetter wrote: > On Tue, Oct 13, 2015 at 04:10:19PM +0300, Jani Nikula wrote: >> On Thu, 08 Oct 2015, Ville Syrjälä wrote: >> > On Thu, Oct 08, 2015 at 10:17:30AM +0200, Daniel Vetter wrote: >> >> On Wed, Oct 07, 2015 at 10:08:24PM +0300, ville.syrj...@linux.intel.com >> >> wrote: >> >> > From: Ville Syrjälä >> >> > >> >> > We accidentally lost the initial DPLL register write in >> >> > 1c4e02746147 drm/i915: Fix DVO 2x clock enable on 830M >> >> > >> >> > The "three times for luck" hack probably saved us from a total >> >> > disaster. But anyway, bring the initial write back so that the >> >> > code actually makes some sense. >> >> > >> >> > Cc: sta...@vger.kernel.org >> >> > Cc: Nick Bowler >> >> Reported-and-tested-by: Nick Bowler >> >> References: >> >> http://lists.freedesktop.org/archives/intel-gfx/2015-October/077463.html >> >> >> >> > Signed-off-by: Ville Syrjälä >> >> > --- >> >> > drivers/gpu/drm/i915/intel_display.c | 2 ++ >> >> > 1 file changed, 2 insertions(+) >> >> > >> >> > diff --git a/drivers/gpu/drm/i915/intel_display.c >> >> > b/drivers/gpu/drm/i915/intel_display.c >> >> > index 147e700..f4fdff9 100644 >> >> > --- a/drivers/gpu/drm/i915/intel_display.c >> >> > +++ b/drivers/gpu/drm/i915/intel_display.c >> >> > @@ -1743,6 +1743,8 @@ static void i9xx_enable_pll(struct intel_crtc >> >> > *crtc) >> >> >I915_READ(DPLL(!crtc->pipe)) | >> >> > DPLL_DVO_2X_MODE); >> >> >> >> Don't we also need a POSTING_READ here to make sure the two-step 2x mode >> >> sequence is still followed? >> > >> > We don't do write combining on registers, and there are no shadow >> > register type of things to consider in this case either. >> > >> >> >> >> With that addressed Reviewed-by: Daniel Vetter >> >> >> Daniel, are you happy with the responses about posting reads, for both >> patches? > > Yeah, acked on irc but forgot to follow up. Both pushed to drm-intel-fixes, thanks for the patches and review. BR, Jani. > -Daniel > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch -- Jani Nikula, Intel Open Source Technology Center ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH 1/2] drm/i915: Restore lost DPLL register write on gen2-4
On Tue, Oct 13, 2015 at 04:10:19PM +0300, Jani Nikula wrote: > On Thu, 08 Oct 2015, Ville Syrjälä wrote: > > On Thu, Oct 08, 2015 at 10:17:30AM +0200, Daniel Vetter wrote: > >> On Wed, Oct 07, 2015 at 10:08:24PM +0300, ville.syrj...@linux.intel.com > >> wrote: > >> > From: Ville Syrjälä > >> > > >> > We accidentally lost the initial DPLL register write in > >> > 1c4e02746147 drm/i915: Fix DVO 2x clock enable on 830M > >> > > >> > The "three times for luck" hack probably saved us from a total > >> > disaster. But anyway, bring the initial write back so that the > >> > code actually makes some sense. > >> > > >> > Cc: sta...@vger.kernel.org > >> > Cc: Nick Bowler > >> Reported-and-tested-by: Nick Bowler > >> References: > >> http://lists.freedesktop.org/archives/intel-gfx/2015-October/077463.html > >> > >> > Signed-off-by: Ville Syrjälä > >> > --- > >> > drivers/gpu/drm/i915/intel_display.c | 2 ++ > >> > 1 file changed, 2 insertions(+) > >> > > >> > diff --git a/drivers/gpu/drm/i915/intel_display.c > >> > b/drivers/gpu/drm/i915/intel_display.c > >> > index 147e700..f4fdff9 100644 > >> > --- a/drivers/gpu/drm/i915/intel_display.c > >> > +++ b/drivers/gpu/drm/i915/intel_display.c > >> > @@ -1743,6 +1743,8 @@ static void i9xx_enable_pll(struct intel_crtc > >> > *crtc) > >> > I915_READ(DPLL(!crtc->pipe)) | > >> > DPLL_DVO_2X_MODE); > >> > >> Don't we also need a POSTING_READ here to make sure the two-step 2x mode > >> sequence is still followed? > > > > We don't do write combining on registers, and there are no shadow > > register type of things to consider in this case either. > > > >> > >> With that addressed Reviewed-by: Daniel Vetter > > > Daniel, are you happy with the responses about posting reads, for both > patches? Yeah, acked on irc but forgot to follow up. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH 1/2] drm/i915: Restore lost DPLL register write on gen2-4
On Thu, 08 Oct 2015, Ville Syrjälä wrote: > On Thu, Oct 08, 2015 at 10:17:30AM +0200, Daniel Vetter wrote: >> On Wed, Oct 07, 2015 at 10:08:24PM +0300, ville.syrj...@linux.intel.com >> wrote: >> > From: Ville Syrjälä >> > >> > We accidentally lost the initial DPLL register write in >> > 1c4e02746147 drm/i915: Fix DVO 2x clock enable on 830M >> > >> > The "three times for luck" hack probably saved us from a total >> > disaster. But anyway, bring the initial write back so that the >> > code actually makes some sense. >> > >> > Cc: sta...@vger.kernel.org >> > Cc: Nick Bowler >> Reported-and-tested-by: Nick Bowler >> References: >> http://lists.freedesktop.org/archives/intel-gfx/2015-October/077463.html >> >> > Signed-off-by: Ville Syrjälä >> > --- >> > drivers/gpu/drm/i915/intel_display.c | 2 ++ >> > 1 file changed, 2 insertions(+) >> > >> > diff --git a/drivers/gpu/drm/i915/intel_display.c >> > b/drivers/gpu/drm/i915/intel_display.c >> > index 147e700..f4fdff9 100644 >> > --- a/drivers/gpu/drm/i915/intel_display.c >> > +++ b/drivers/gpu/drm/i915/intel_display.c >> > @@ -1743,6 +1743,8 @@ static void i9xx_enable_pll(struct intel_crtc *crtc) >> > I915_READ(DPLL(!crtc->pipe)) | DPLL_DVO_2X_MODE); >> >> Don't we also need a POSTING_READ here to make sure the two-step 2x mode >> sequence is still followed? > > We don't do write combining on registers, and there are no shadow > register type of things to consider in this case either. > >> >> With that addressed Reviewed-by: Daniel Vetter Daniel, are you happy with the responses about posting reads, for both patches? BR, Jani. >> >} >> > >> > + I915_WRITE(reg, dpll); >> > + >> >/* Wait for the clocks to stabilize. */ >> >POSTING_READ(reg); >> >udelay(150); >> > -- >> > 2.4.9 >> > >> > ___ >> > Intel-gfx mailing list >> > Intel-gfx@lists.freedesktop.org >> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx >> >> -- >> Daniel Vetter >> Software Engineer, Intel Corporation >> http://blog.ffwll.ch > > -- > Ville Syrjälä > Intel OTC > ___ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Jani Nikula, Intel Open Source Technology Center ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH 1/2] drm/i915: Restore lost DPLL register write on gen2-4
On Thu, Oct 08, 2015 at 10:17:30AM +0200, Daniel Vetter wrote: > On Wed, Oct 07, 2015 at 10:08:24PM +0300, ville.syrj...@linux.intel.com wrote: > > From: Ville Syrjälä > > > > We accidentally lost the initial DPLL register write in > > 1c4e02746147 drm/i915: Fix DVO 2x clock enable on 830M > > > > The "three times for luck" hack probably saved us from a total > > disaster. But anyway, bring the initial write back so that the > > code actually makes some sense. > > > > Cc: sta...@vger.kernel.org > > Cc: Nick Bowler > Reported-and-tested-by: Nick Bowler > References: > http://lists.freedesktop.org/archives/intel-gfx/2015-October/077463.html > > > Signed-off-by: Ville Syrjälä > > --- > > drivers/gpu/drm/i915/intel_display.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/intel_display.c > > b/drivers/gpu/drm/i915/intel_display.c > > index 147e700..f4fdff9 100644 > > --- a/drivers/gpu/drm/i915/intel_display.c > > +++ b/drivers/gpu/drm/i915/intel_display.c > > @@ -1743,6 +1743,8 @@ static void i9xx_enable_pll(struct intel_crtc *crtc) > >I915_READ(DPLL(!crtc->pipe)) | DPLL_DVO_2X_MODE); > > Don't we also need a POSTING_READ here to make sure the two-step 2x mode > sequence is still followed? We don't do write combining on registers, and there are no shadow register type of things to consider in this case either. > > With that addressed Reviewed-by: Daniel Vetter > > } > > > > + I915_WRITE(reg, dpll); > > + > > /* Wait for the clocks to stabilize. */ > > POSTING_READ(reg); > > udelay(150); > > -- > > 2.4.9 > > > > ___ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx > > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch -- Ville Syrjälä Intel OTC ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [PATCH 1/2] drm/i915: Restore lost DPLL register write on gen2-4
On Wed, Oct 07, 2015 at 10:08:24PM +0300, ville.syrj...@linux.intel.com wrote: > From: Ville Syrjälä > > We accidentally lost the initial DPLL register write in > 1c4e02746147 drm/i915: Fix DVO 2x clock enable on 830M > > The "three times for luck" hack probably saved us from a total > disaster. But anyway, bring the initial write back so that the > code actually makes some sense. > > Cc: sta...@vger.kernel.org > Cc: Nick Bowler Reported-and-tested-by: Nick Bowler References: http://lists.freedesktop.org/archives/intel-gfx/2015-October/077463.html > Signed-off-by: Ville Syrjälä > --- > drivers/gpu/drm/i915/intel_display.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_display.c > b/drivers/gpu/drm/i915/intel_display.c > index 147e700..f4fdff9 100644 > --- a/drivers/gpu/drm/i915/intel_display.c > +++ b/drivers/gpu/drm/i915/intel_display.c > @@ -1743,6 +1743,8 @@ static void i9xx_enable_pll(struct intel_crtc *crtc) > I915_READ(DPLL(!crtc->pipe)) | DPLL_DVO_2X_MODE); Don't we also need a POSTING_READ here to make sure the two-step 2x mode sequence is still followed? With that addressed Reviewed-by: Daniel Vetter > } > > + I915_WRITE(reg, dpll); > + > /* Wait for the clocks to stabilize. */ > POSTING_READ(reg); > udelay(150); > -- > 2.4.9 > > ___ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
[Intel-gfx] [PATCH 1/2] drm/i915: Restore lost DPLL register write on gen2-4
From: Ville Syrjälä We accidentally lost the initial DPLL register write in 1c4e02746147 drm/i915: Fix DVO 2x clock enable on 830M The "three times for luck" hack probably saved us from a total disaster. But anyway, bring the initial write back so that the code actually makes some sense. Cc: sta...@vger.kernel.org Cc: Nick Bowler Signed-off-by: Ville Syrjälä --- drivers/gpu/drm/i915/intel_display.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 147e700..f4fdff9 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -1743,6 +1743,8 @@ static void i9xx_enable_pll(struct intel_crtc *crtc) I915_READ(DPLL(!crtc->pipe)) | DPLL_DVO_2X_MODE); } + I915_WRITE(reg, dpll); + /* Wait for the clocks to stabilize. */ POSTING_READ(reg); udelay(150); -- 2.4.9 ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
