[Intel-gfx] [PATCH 2/2] drm/i915: Update sprite watermarks outside vblank evasion
Matt Roper
matthew.d.roper at intel.com
Tue Jun 23 07:29:58 PDT 2015
On Tue, Jun 23, 2015 at 09:34:50AM +0200, Daniel Vetter wrote:
> On Mon, Jun 22, 2015 at 06:30:33PM -0700, Matt Roper wrote:
> > We never removed the sprite watermark updates from our low-level
> > foo_update_plane() functions; since our hardware updates happen under
> > vblank evasion, we're not supposed to be calling potentially sleeping
> > functions there (since interrupts are disabled). We do already have a
> > mechanism that's supposed to be used to update sprite watermarks in the
> > post-evasion function intel_post_plane_update(), but at the moment it's
> > only being used for updates caused by plane disables.
> >
> > To fix this oversight we need to make a few changes:
> >
> > * When intel_plane_atomic_calc_changes() calls intel_wm_need_update()
> > to determine whether watermarks need an update, we need to set the
> > 'atomic.update_sprite_watermarks' flag rather than the
> > 'atomic.update_wm' flag when the plane in question is a sprite. Some
> > platforms don't care about this change since the two types of update
> > do the same thing, but some platforms (e.g., ILK-style watermarks)
> > need to specifically use the sprite update function to update cached
> > watermark parameters.
> >
> > * intel_wm_need_update() needs to also look for plane size changes
> > (previously it only checked tiling & rotation).
> >
> > With the above changes, the need for sprite watermark updates should be
> > properly flagged at atomic 'check' time and handled at 'commit' time in
> > post-evasion, so we can drop the direct calls to
> > intel_update_sprite_watermarks() from all of the
> > intel_plane->update_plane() handlers. We'll also toss a
> > WARN_ON(irqs_disabled()) into the watermark update functions to avoid
> > such mistakes in the future.
> >
> > Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
>
> Why do even still need a separate sprite wm update hooks? Aren't we yet
> recomputing wm values for all planes if something changes, then diffing
> them with the current one and updating if anything changed? That seems to
> be what update_sprite_wm essentially does, except it's pre-atomic and
> open-codes the updates ...
Some platforms stage a copy of plane/pipe state in 'wm parameter'
structures and only update the pipe wm params with the new plane values
when update_sprite_wm is called. That's definitely something my main
watermark series kills off, but until we get to that point and remove
the extra state staging in 'params' I think we still need to make sure
the update_sprite_wm is called appropriately to make sure watermarks use
the right values on all platforms. I figured these two patches were a
quick fix for a known bug while we get the main watermark series
hammered out.
Matt
>
> Ofc there's still that ilk w/a around which needs to be moved to a
> suitable place.
> -Daniel
> > ---
> > drivers/gpu/drm/i915/intel_display.c | 23 ++++++++++++++++-------
> > drivers/gpu/drm/i915/intel_pm.c | 2 ++
> > drivers/gpu/drm/i915/intel_sprite.c | 12 ------------
> > 3 files changed, 18 insertions(+), 19 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> > index 5e8e01c..181aedd 100644
> > --- a/drivers/gpu/drm/i915/intel_display.c
> > +++ b/drivers/gpu/drm/i915/intel_display.c
> > @@ -11575,13 +11575,17 @@ retry:
> > static bool intel_wm_need_update(struct drm_plane *plane,
> > struct drm_plane_state *state)
> > {
> > - /* Update watermarks on tiling changes. */
> > + struct intel_plane_state *new = to_intel_plane_state(state);
> > + struct intel_plane_state *cur = to_intel_plane_state(plane->state);
> > +
> > + /* Update watermarks on tiling changes or size changes. */
> > if (!plane->state->fb || !state->fb ||
> > plane->state->fb->modifier[0] != state->fb->modifier[0] ||
> > - plane->state->rotation != state->rotation)
> > - return true;
> > -
> > - if (plane->state->crtc_w != state->crtc_w)
> > + plane->state->rotation != state->rotation ||
> > + drm_rect_width(&new->src) != drm_rect_width(&cur->src) ||
> > + drm_rect_height(&new->src) != drm_rect_height(&cur->src) ||
> > + drm_rect_width(&new->dst) != drm_rect_width(&cur->dst) ||
> > + drm_rect_height(&new->dst) != drm_rect_height(&cur->dst))
> > return true;
> >
> > return false;
> > @@ -11645,8 +11649,13 @@ int intel_plane_atomic_calc_changes(struct drm_crtc_state *crtc_state,
> > plane->base.id, was_visible, visible,
> > turn_off, turn_on, mode_changed);
> >
> > - if (intel_wm_need_update(plane, plane_state))
> > - intel_crtc->atomic.update_wm = true;
> > + if (intel_wm_need_update(plane, plane_state)) {
> > + if (plane->type == DRM_PLANE_TYPE_OVERLAY)
> > + intel_crtc->atomic.update_sprite_watermarks |=
> > + 1 << i;
> > + else
> > + intel_crtc->atomic.update_wm = true;
> > + }
> >
> > switch (plane->type) {
> > case DRM_PLANE_TYPE_PRIMARY:
> > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > index 4d3cb70..2470ede 100644
> > --- a/drivers/gpu/drm/i915/intel_pm.c
> > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > @@ -3750,6 +3750,7 @@ void intel_update_watermarks(struct drm_crtc *crtc)
> > {
> > struct drm_i915_private *dev_priv = crtc->dev->dev_private;
> >
> > + WARN_ON(irqs_disabled());
> > if (dev_priv->display.update_wm)
> > dev_priv->display.update_wm(crtc);
> > }
> > @@ -3770,6 +3771,7 @@ void intel_update_sprite_watermarks(struct drm_plane *plane,
> > unsigned int dst_h = drm_rect_height(&state->dst);
> > bool scaled = (src_w != dst_w || src_h != dst_h);
> >
> > + WARN_ON(irqs_disabled());
> > if (dev_priv->display.update_sprite_wm)
> > dev_priv->display.update_sprite_wm(plane, crtc,
> > sprite_width, sprite_height,
> > diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
> > index b627067..ce2fa92 100644
> > --- a/drivers/gpu/drm/i915/intel_sprite.c
> > +++ b/drivers/gpu/drm/i915/intel_sprite.c
> > @@ -199,8 +199,6 @@ skl_update_plane(struct drm_plane *drm_plane, struct drm_crtc *crtc,
> > rotation = drm_plane->state->rotation;
> > plane_ctl |= skl_plane_ctl_rotation(rotation);
> >
> > - intel_update_sprite_watermarks(drm_plane, crtc);
> > -
> > stride_div = intel_fb_stride_alignment(dev, fb->modifier[0],
> > fb->pixel_format);
> >
> > @@ -282,8 +280,6 @@ skl_disable_plane(struct drm_plane *dplane, struct drm_crtc *crtc)
> >
> > I915_WRITE(PLANE_SURF(pipe, plane), 0);
> > POSTING_READ(PLANE_SURF(pipe, plane));
> > -
> > - intel_update_sprite_watermarks(dplane, crtc);
> > }
> >
> > static void
> > @@ -399,8 +395,6 @@ vlv_update_plane(struct drm_plane *dplane, struct drm_crtc *crtc,
> > if (obj->tiling_mode != I915_TILING_NONE)
> > sprctl |= SP_TILED;
> >
> > - intel_update_sprite_watermarks(dplane, crtc);
> > -
> > /* Sizes are 0 based */
> > src_w--;
> > src_h--;
> > @@ -465,8 +459,6 @@ vlv_disable_plane(struct drm_plane *dplane, struct drm_crtc *crtc)
> >
> > I915_WRITE(SPSURF(pipe, plane), 0);
> > POSTING_READ(SPSURF(pipe, plane));
> > -
> > - intel_update_sprite_watermarks(dplane, crtc);
> > }
> >
> > static void
> > @@ -530,8 +522,6 @@ ivb_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
> > if (IS_HASWELL(dev) || IS_BROADWELL(dev))
> > sprctl |= SPRITE_PIPE_CSC_ENABLE;
> >
> > - intel_update_sprite_watermarks(plane, crtc);
> > -
> > /* Sizes are 0 based */
> > src_w--;
> > src_h--;
> > @@ -665,8 +655,6 @@ ilk_update_plane(struct drm_plane *plane, struct drm_crtc *crtc,
> > if (IS_GEN6(dev))
> > dvscntr |= DVS_TRICKLE_FEED_DISABLE; /* must disable */
> >
> > - intel_update_sprite_watermarks(plane, crtc);
> > -
> > /* Sizes are 0 based */
> > src_w--;
> > src_h--;
> > --
> > 2.1.4
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
--
Matt Roper
Graphics Software Engineer
IoTG Platform Enabling & Development
Intel Corporation
(916) 356-2795
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