[PATCH] drm/i915: disable non-sequential pfits on ivb/hsw

[PATCH] drm/i915: disable non-sequential pfits on ivb/hsw

[Chris Bainbridge]

The existing code assumes a sequential mapping of panel fitters to pipes
(pfit0-pipeA, pfit1-pipeB, pfit2-pipeC), but boot firmware can
arbitrarily assign any pipe to a pfit on IVB hardware e.g. Macbook UEFI
uses pfit 0 and pipe C for eDP1 when the firmware boots in a non-16:10
resolution (the last-used resolution is stored in NVRAM by OS X so the
firmware can immediately restore it at boot). When this happens, the
display will appear letterboxed due to incorrect aspect ratio and
attempting to switch to alternative resolutions will fail. Fix this by
disabling any panel fitters which have been non-sequentially assigned at
boot time.

Link: https://bugs.freedesktop.org/show_bug.cgi?id=93523
Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
---
 drivers/gpu/drm/i915/intel_display.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 32cf97346978..9e588139a2dd 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9170,6 +9170,24 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	uint32_t tmp;
+	int pipe;
+
+	/*
+	 * PF_CTL assumes panel fitter 0 is on pipe A, panel fitter 1 is on
+	 * pipe B, and panel fitter 2 is on pipe C, but firmware can init IVB
+	 * panel fitters to any arbitrary pipe (Macbook UEFI uses pfit 0 for
+	 * pipe C), so find and disable any other mappings.
+	 */
+	for (pipe = 0; pipe < INTEL_INFO(dev)->num_pipes; pipe++) {
+		tmp = I915_READ(PF_CTL(pipe));
+		if (IS_GEN7(dev) && (tmp & PF_ENABLE) &&
+		    PF_PIPE_SEL_IVB(pipe) != (tmp & PF_PIPE_SEL_MASK_IVB)) {
+			DRM_DEBUG_KMS("disabling initial panel fitter\n");
+			I915_WRITE(PF_CTL(pipe), 0);
+			I915_WRITE(PF_WIN_POS(pipe), 0);
+			I915_WRITE(PF_WIN_SZ(pipe), 0);
+		}
+	}
 
 	tmp = I915_READ(PF_CTL(crtc->pipe));
 
@@ -9177,14 +9195,6 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
 		pipe_config->pch_pfit.enabled = true;
 		pipe_config->pch_pfit.pos = I915_READ(PF_WIN_POS(crtc->pipe));
 		pipe_config->pch_pfit.size = I915_READ(PF_WIN_SZ(crtc->pipe));
-
-		/* We currently do not free assignements of panel fitters on
-		 * ivb/hsw (since we don't use the higher upscaling modes which
-		 * differentiates them) so just WARN about this case for now. */
-		if (IS_GEN7(dev)) {
-			WARN_ON((tmp & PF_PIPE_SEL_MASK_IVB) !=
-				PF_PIPE_SEL_IVB(crtc->pipe));
-		}
 	}
 }
 
-- 
2.1.4

Re: [Intel-gfx] [PATCH] drm/i915: disable non-sequential pfits on ivb/hsw

[Daniel Vetter]

On Wed, Jan 13, 2016 at 02:33:47PM +0000, Chris Bainbridge wrote:
> The existing code assumes a sequential mapping of panel fitters to pipes
> (pfit0-pipeA, pfit1-pipeB, pfit2-pipeC), but boot firmware can
> arbitrarily assign any pipe to a pfit on IVB hardware e.g. Macbook UEFI
> uses pfit 0 and pipe C for eDP1 when the firmware boots in a non-16:10
> resolution (the last-used resolution is stored in NVRAM by OS X so the
> firmware can immediately restore it at boot). When this happens, the
> display will appear letterboxed due to incorrect aspect ratio and
> attempting to switch to alternative resolutions will fail. Fix this by
> disabling any panel fitters which have been non-sequentially assigned at
> boot time.
> 
> Link: https://bugs.freedesktop.org/show_bug.cgi?id=93523
> Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 26 ++++++++++++++++++--------
>  1 file changed, 18 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 32cf97346978..9e588139a2dd 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -9170,6 +9170,24 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,

get_config should never touch hw state, only read it out. The right place
to put fixup code is in sanitize_crtc. What we need in get_config would be
a check to make sure pfit is assigned to our pipe (and not take over the
state if so).
-Daniel

>  	struct drm_device *dev = crtc->base.dev;
>  	struct drm_i915_private *dev_priv = dev->dev_private;
>  	uint32_t tmp;
> +	int pipe;
> +
> +	/*
> +	 * PF_CTL assumes panel fitter 0 is on pipe A, panel fitter 1 is on
> +	 * pipe B, and panel fitter 2 is on pipe C, but firmware can init IVB
> +	 * panel fitters to any arbitrary pipe (Macbook UEFI uses pfit 0 for
> +	 * pipe C), so find and disable any other mappings.
> +	 */
> +	for (pipe = 0; pipe < INTEL_INFO(dev)->num_pipes; pipe++) {
> +		tmp = I915_READ(PF_CTL(pipe));
> +		if (IS_GEN7(dev) && (tmp & PF_ENABLE) &&
> +		    PF_PIPE_SEL_IVB(pipe) != (tmp & PF_PIPE_SEL_MASK_IVB)) {
> +			DRM_DEBUG_KMS("disabling initial panel fitter\n");
> +			I915_WRITE(PF_CTL(pipe), 0);
> +			I915_WRITE(PF_WIN_POS(pipe), 0);
> +			I915_WRITE(PF_WIN_SZ(pipe), 0);
> +		}
> +	}
>  
>  	tmp = I915_READ(PF_CTL(crtc->pipe));
>  
> @@ -9177,14 +9195,6 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
>  		pipe_config->pch_pfit.enabled = true;
>  		pipe_config->pch_pfit.pos = I915_READ(PF_WIN_POS(crtc->pipe));
>  		pipe_config->pch_pfit.size = I915_READ(PF_WIN_SZ(crtc->pipe));
> -
> -		/* We currently do not free assignements of panel fitters on
> -		 * ivb/hsw (since we don't use the higher upscaling modes which
> -		 * differentiates them) so just WARN about this case for now. */
> -		if (IS_GEN7(dev)) {
> -			WARN_ON((tmp & PF_PIPE_SEL_MASK_IVB) !=
> -				PF_PIPE_SEL_IVB(crtc->pipe));
> -		}
>  	}
>  }
>  
> -- 
> 2.1.4
> 
> _______________________________________________
> 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

Re: [Intel-gfx] [PATCH] drm/i915: disable non-sequential pfits on ivb/hsw

[Daniel Vetter]

On Wed, Jan 13, 2016 at 05:13:31PM +0100, Daniel Vetter wrote:
> On Wed, Jan 13, 2016 at 02:33:47PM +0000, Chris Bainbridge wrote:
> > The existing code assumes a sequential mapping of panel fitters to pipes
> > (pfit0-pipeA, pfit1-pipeB, pfit2-pipeC), but boot firmware can
> > arbitrarily assign any pipe to a pfit on IVB hardware e.g. Macbook UEFI
> > uses pfit 0 and pipe C for eDP1 when the firmware boots in a non-16:10
> > resolution (the last-used resolution is stored in NVRAM by OS X so the
> > firmware can immediately restore it at boot). When this happens, the
> > display will appear letterboxed due to incorrect aspect ratio and
> > attempting to switch to alternative resolutions will fail. Fix this by
> > disabling any panel fitters which have been non-sequentially assigned at
> > boot time.
> > 
> > Link: https://bugs.freedesktop.org/show_bug.cgi?id=93523
> > Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
> > ---
> >  drivers/gpu/drm/i915/intel_display.c | 26 ++++++++++++++++++--------
> >  1 file changed, 18 insertions(+), 8 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> > index 32cf97346978..9e588139a2dd 100644
> > --- a/drivers/gpu/drm/i915/intel_display.c
> > +++ b/drivers/gpu/drm/i915/intel_display.c
> > @@ -9170,6 +9170,24 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
> 
> get_config should never touch hw state, only read it out. The right place
> to put fixup code is in sanitize_crtc. What we need in get_config would be
> a check to make sure pfit is assigned to our pipe (and not take over the
> state if so).

maybe even throw a new sanitize_pfit function in for clarity, since the
problem is that pfit is _not_ associated with the crtc at a hw level.
-Daniel

> 
> >  	struct drm_device *dev = crtc->base.dev;
> >  	struct drm_i915_private *dev_priv = dev->dev_private;
> >  	uint32_t tmp;
> > +	int pipe;
> > +
> > +	/*
> > +	 * PF_CTL assumes panel fitter 0 is on pipe A, panel fitter 1 is on
> > +	 * pipe B, and panel fitter 2 is on pipe C, but firmware can init IVB
> > +	 * panel fitters to any arbitrary pipe (Macbook UEFI uses pfit 0 for
> > +	 * pipe C), so find and disable any other mappings.
> > +	 */
> > +	for (pipe = 0; pipe < INTEL_INFO(dev)->num_pipes; pipe++) {
> > +		tmp = I915_READ(PF_CTL(pipe));
> > +		if (IS_GEN7(dev) && (tmp & PF_ENABLE) &&
> > +		    PF_PIPE_SEL_IVB(pipe) != (tmp & PF_PIPE_SEL_MASK_IVB)) {
> > +			DRM_DEBUG_KMS("disabling initial panel fitter\n");
> > +			I915_WRITE(PF_CTL(pipe), 0);
> > +			I915_WRITE(PF_WIN_POS(pipe), 0);
> > +			I915_WRITE(PF_WIN_SZ(pipe), 0);
> > +		}
> > +	}
> >  
> >  	tmp = I915_READ(PF_CTL(crtc->pipe));
> >  
> > @@ -9177,14 +9195,6 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
> >  		pipe_config->pch_pfit.enabled = true;
> >  		pipe_config->pch_pfit.pos = I915_READ(PF_WIN_POS(crtc->pipe));
> >  		pipe_config->pch_pfit.size = I915_READ(PF_WIN_SZ(crtc->pipe));
> > -
> > -		/* We currently do not free assignements of panel fitters on
> > -		 * ivb/hsw (since we don't use the higher upscaling modes which
> > -		 * differentiates them) so just WARN about this case for now. */
> > -		if (IS_GEN7(dev)) {
> > -			WARN_ON((tmp & PF_PIPE_SEL_MASK_IVB) !=
> > -				PF_PIPE_SEL_IVB(crtc->pipe));
> > -		}
> >  	}
> >  }
> >  
> > -- 
> > 2.1.4
> > 
> > _______________________________________________
> > 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

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [Intel-gfx] [PATCH] drm/i915: disable non-sequential pfits on ivb/hsw

[Ville Syrjälä]

On Wed, Jan 13, 2016 at 05:14:15PM +0100, Daniel Vetter wrote:
> On Wed, Jan 13, 2016 at 05:13:31PM +0100, Daniel Vetter wrote:
> > On Wed, Jan 13, 2016 at 02:33:47PM +0000, Chris Bainbridge wrote:
> > > The existing code assumes a sequential mapping of panel fitters to pipes
> > > (pfit0-pipeA, pfit1-pipeB, pfit2-pipeC), but boot firmware can
> > > arbitrarily assign any pipe to a pfit on IVB hardware e.g. Macbook UEFI
> > > uses pfit 0 and pipe C for eDP1 when the firmware boots in a non-16:10
> > > resolution (the last-used resolution is stored in NVRAM by OS X so the
> > > firmware can immediately restore it at boot). When this happens, the
> > > display will appear letterboxed due to incorrect aspect ratio and
> > > attempting to switch to alternative resolutions will fail. Fix this by
> > > disabling any panel fitters which have been non-sequentially assigned at
> > > boot time.
> > > 
> > > Link: https://bugs.freedesktop.org/show_bug.cgi?id=93523
> > > Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
> > > ---
> > >  drivers/gpu/drm/i915/intel_display.c | 26 ++++++++++++++++++--------
> > >  1 file changed, 18 insertions(+), 8 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> > > index 32cf97346978..9e588139a2dd 100644
> > > --- a/drivers/gpu/drm/i915/intel_display.c
> > > +++ b/drivers/gpu/drm/i915/intel_display.c
> > > @@ -9170,6 +9170,24 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
> > 
> > get_config should never touch hw state, only read it out. The right place
> > to put fixup code is in sanitize_crtc. What we need in get_config would be
> > a check to make sure pfit is assigned to our pipe (and not take over the
> > state if so).
> 
> maybe even throw a new sanitize_pfit function in for clarity, since the
> problem is that pfit is _not_ associated with the crtc at a hw level.

Ideally we'd make the crtc<->pfit mapping flexible in the driver since
IIRC the first pfit could have special powers. But I guess it could be
a bit too much work for little gain. Although it shouldn't be too
different from the SKL scaler assignment stuff, so maybe not that much
work...

-- 
Ville Syrjälä
Intel OTC

Re: [Intel-gfx] [PATCH] drm/i915: disable non-sequential pfits on ivb/hsw

[Jani Nikula]

On Wed, 13 Jan 2016, Chris Bainbridge <chris.bainbridge@gmail.com> wrote:
> The existing code assumes a sequential mapping of panel fitters to pipes
> (pfit0-pipeA, pfit1-pipeB, pfit2-pipeC), but boot firmware can
> arbitrarily assign any pipe to a pfit on IVB hardware e.g. Macbook UEFI
> uses pfit 0 and pipe C for eDP1 when the firmware boots in a non-16:10
> resolution (the last-used resolution is stored in NVRAM by OS X so the
> firmware can immediately restore it at boot). When this happens, the
> display will appear letterboxed due to incorrect aspect ratio and
> attempting to switch to alternative resolutions will fail. Fix this by
> disabling any panel fitters which have been non-sequentially assigned at
> boot time.
>
> Link: https://bugs.freedesktop.org/show_bug.cgi?id=93523

s/Link/Bugzilla/

> Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 26 ++++++++++++++++++--------
>  1 file changed, 18 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 32cf97346978..9e588139a2dd 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -9170,6 +9170,24 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
>  	struct drm_device *dev = crtc->base.dev;
>  	struct drm_i915_private *dev_priv = dev->dev_private;
>  	uint32_t tmp;
> +	int pipe;
> +
> +	/*
> +	 * PF_CTL assumes panel fitter 0 is on pipe A, panel fitter 1 is on
> +	 * pipe B, and panel fitter 2 is on pipe C, but firmware can init IVB
> +	 * panel fitters to any arbitrary pipe (Macbook UEFI uses pfit 0 for
> +	 * pipe C), so find and disable any other mappings.
> +	 */
> +	for (pipe = 0; pipe < INTEL_INFO(dev)->num_pipes; pipe++) {
> +		tmp = I915_READ(PF_CTL(pipe));
> +		if (IS_GEN7(dev) && (tmp & PF_ENABLE) &&
> +		    PF_PIPE_SEL_IVB(pipe) != (tmp & PF_PIPE_SEL_MASK_IVB)) {
> +			DRM_DEBUG_KMS("disabling initial panel fitter\n");
> +			I915_WRITE(PF_CTL(pipe), 0);
> +			I915_WRITE(PF_WIN_POS(pipe), 0);
> +			I915_WRITE(PF_WIN_SZ(pipe), 0);
> +		}
> +	}
>  
>  	tmp = I915_READ(PF_CTL(crtc->pipe));
>  
> @@ -9177,14 +9195,6 @@ static void ironlake_get_pfit_config(struct intel_crtc *crtc,
>  		pipe_config->pch_pfit.enabled = true;
>  		pipe_config->pch_pfit.pos = I915_READ(PF_WIN_POS(crtc->pipe));
>  		pipe_config->pch_pfit.size = I915_READ(PF_WIN_SZ(crtc->pipe));
> -
> -		/* We currently do not free assignements of panel fitters on
> -		 * ivb/hsw (since we don't use the higher upscaling modes which
> -		 * differentiates them) so just WARN about this case for now. */
> -		if (IS_GEN7(dev)) {
> -			WARN_ON((tmp & PF_PIPE_SEL_MASK_IVB) !=
> -				PF_PIPE_SEL_IVB(crtc->pipe));
> -		}
>  	}
>  }

-- 
Jani Nikula, Intel Open Source Technology Center