[Intel-gfx] [PATCH 7/8] drm/i915/display/skl+: Drop frontbuffer rendering support

[Daniel Vetter]

On Wed, Aug 18, 2021 at 2:37 AM José Roberto de Souza
<jose.souza at intel.com> wrote:
>
> By now all the userspace applications should have migrated to atomic
> or at least be calling DRM_IOCTL_MODE_DIRTYFB.
>
> With that we can kill frontbuffer rendering support in i915 for
> modern platforms.
>
> So here converting legacy APIs into atomic commits so it can be
> properly handled by driver i915.
>
> Several IGT tests will fail with this changes, because some tests
> were stressing those frontbuffer rendering scenarios that no userspace
> should be using by now, fixes to IGT should be sent soon.
>
> Cc: Daniel Vetter <daniel at ffwll.ch>
> Cc: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Jani Nikula <jani.nikula at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>

Patch looks good in overall direction, but there's more
intel_frontbuffer.c functions to disable, none of the tracking of the
tracking bits should ever be set, maybe even throw some WARN_ON in the
code.
-Daniel

> ---
>  drivers/gpu/drm/i915/display/intel_cursor.c      | 6 ++----
>  drivers/gpu/drm/i915/display/intel_display.c     | 7 ++++++-
>  drivers/gpu/drm/i915/display/intel_frontbuffer.c | 6 ++++++
>  drivers/gpu/drm/i915/i915_drv.h                  | 2 ++
>  4 files changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_cursor.c b/drivers/gpu/drm/i915/display/intel_cursor.c
> index c7618fef01439..5aa996c3b7980 100644
> --- a/drivers/gpu/drm/i915/display/intel_cursor.c
> +++ b/drivers/gpu/drm/i915/display/intel_cursor.c
> @@ -617,6 +617,7 @@ intel_legacy_cursor_update(struct drm_plane *_plane,
>                            u32 src_w, u32 src_h,
>                            struct drm_modeset_acquire_ctx *ctx)
>  {
> +       struct drm_i915_private *i915 = to_i915(_crtc->dev);
>         struct intel_plane *plane = to_intel_plane(_plane);
>         struct intel_crtc *crtc = to_intel_crtc(_crtc);
>         struct intel_plane_state *old_plane_state =
> @@ -633,12 +634,9 @@ intel_legacy_cursor_update(struct drm_plane *_plane,
>          * PSR2 selective fetch also requires the slow path as
>          * PSR2 plane and transcoder registers can only be updated during
>          * vblank.
> -        *
> -        * FIXME bigjoiner fastpath would be good
>          */
>         if (!crtc_state->hw.active || intel_crtc_needs_modeset(crtc_state) ||
> -           crtc_state->update_pipe || crtc_state->bigjoiner ||
> -           crtc_state->enable_psr2_sel_fetch)
> +           crtc_state->update_pipe || !HAS_FRONTBUFFER_RENDERING(i915))
>                 goto slow;
>
>         /*
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index e55c9e2cb254a..f700544454ad5 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -11744,10 +11744,15 @@ static int intel_user_framebuffer_dirty(struct drm_framebuffer *fb,
>                                         unsigned num_clips)
>  {
>         struct drm_i915_gem_object *obj = intel_fb_obj(fb);
> +       struct drm_i915_private *i915 = to_i915(obj->base.dev);
>
>         i915_gem_object_flush_if_display(obj);
> -       intel_frontbuffer_flush(to_intel_frontbuffer(fb), ORIGIN_DIRTYFB);
>
> +       if (!HAS_FRONTBUFFER_RENDERING(i915))
> +               return drm_atomic_helper_dirtyfb(fb, file, flags, color, clips,
> +                                                num_clips);
> +
> +       intel_frontbuffer_flush(to_intel_frontbuffer(fb), ORIGIN_DIRTYFB);
>         return 0;
>  }
>
> diff --git a/drivers/gpu/drm/i915/display/intel_frontbuffer.c b/drivers/gpu/drm/i915/display/intel_frontbuffer.c
> index e4834d84ce5e3..6be2f767a203c 100644
> --- a/drivers/gpu/drm/i915/display/intel_frontbuffer.c
> +++ b/drivers/gpu/drm/i915/display/intel_frontbuffer.c
> @@ -91,6 +91,9 @@ static void frontbuffer_flush(struct drm_i915_private *i915,
>
>         trace_intel_frontbuffer_flush(frontbuffer_bits, origin);
>
> +       if (!HAS_FRONTBUFFER_RENDERING(i915))
> +               return;
> +
>         might_sleep();
>         intel_edp_drrs_flush(i915, frontbuffer_bits);
>         intel_psr_flush(i915, frontbuffer_bits, origin);
> @@ -179,6 +182,9 @@ void __intel_fb_invalidate(struct intel_frontbuffer *front,
>
>         trace_intel_frontbuffer_invalidate(frontbuffer_bits, origin);
>
> +       if (!HAS_FRONTBUFFER_RENDERING(i915))
> +               return;
> +
>         might_sleep();
>         intel_psr_invalidate(i915, frontbuffer_bits, origin);
>         intel_edp_drrs_invalidate(i915, frontbuffer_bits);
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 1ea27c4e94a6d..fe1dc8b7871a0 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1719,6 +1719,8 @@ IS_SUBPLATFORM(const struct drm_i915_private *i915,
>
>  #define HAS_VRR(i915)  (GRAPHICS_VER(i915) >= 12)
>
> +#define HAS_FRONTBUFFER_RENDERING(i915)        (GRAPHICS_VER(i915) < 9)
> +
>  /* Only valid when HAS_DISPLAY() is true */
>  #define INTEL_DISPLAY_ENABLED(dev_priv) \
>         (drm_WARN_ON(&(dev_priv)->drm, !HAS_DISPLAY(dev_priv)), !(dev_priv)->params.disable_display)
> --
> 2.32.0
>


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