On Fri, Jan 27, 2023 at 04:30:02PM +0100, Andrzej Hajda wrote:
> Current implementation of async flip w/a relies on assumption that
> previous atomic commit contains valid information if async_flip is still
> enabled on the plane. It is incorrect. If previous commit did not modify
> the plane its state->uapi.async_flip can be false. As a result DMAR/PIPE
> errors can be observed:
> i915 0000:00:02.0: [drm] *ERROR* Fault errors on pipe A: 0x00000080
> i915 0000:00:02.0: [drm] *ERROR* Fault errors on pipe A: 0x00000080
> DMAR: DRHD: handling fault status reg 2
> DMAR: [DMA Read NO_PASID] Request device [00:02.0] fault addr 0x0 [fault reason 0x06] PTE Read access is not set
>
> v2: update async_flip_planes in more reliable places (Ville)
> v3: reset async_flip_planes and do_async_flip in more scenarios (Ville)
> v4: move all resets to plane loops (Ville)
>
> Signed-off-by: Andrzej Hajda <andrzej.hajda@xxxxxxxxx>
> ---
> Hi Ville,
>
> I am not sure about this change. I wonder if in case of
> for*plane loops code could be like:
>
> new_crtc_state->async_flip_planes &= ~BIT(plane->id);
> if (!new_crtc_state->async_flip_planes)
> new_crtc_state->do_async_flip = false;
>
> But let's see what CI says.
>
> Regards
> Andrzej
> ---
> drivers/gpu/drm/i915/display/intel_atomic_plane.c | 5 ++++-
> drivers/gpu/drm/i915/display/intel_color.c | 3 +++
> drivers/gpu/drm/i915/display/intel_display.c | 9 ++++++---
> drivers/gpu/drm/i915/display/intel_display_types.h | 3 +++
> drivers/gpu/drm/i915/display/skl_watermark.c | 4 ++++
> 5 files changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> index 1409bcfb6fd3d9..3bd8f7eb75a60b 100644
> --- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> +++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> @@ -363,6 +363,7 @@ void intel_plane_set_invisible(struct intel_crtc_state *crtc_state,
> crtc_state->scaled_planes &= ~BIT(plane->id);
> crtc_state->nv12_planes &= ~BIT(plane->id);
> crtc_state->c8_planes &= ~BIT(plane->id);
> + crtc_state->async_flip_planes &= ~BIT(plane->id);
> crtc_state->data_rate[plane->id] = 0;
> crtc_state->data_rate_y[plane->id] = 0;
> crtc_state->rel_data_rate[plane->id] = 0;
> @@ -582,8 +583,10 @@ static int intel_plane_atomic_calc_changes(const struct intel_crtc_state *old_cr
> intel_plane_is_scaled(new_plane_state))))
> new_crtc_state->disable_lp_wm = true;
>
> - if (intel_plane_do_async_flip(plane, old_crtc_state, new_crtc_state))
> + if (intel_plane_do_async_flip(plane, old_crtc_state, new_crtc_state)) {
> new_crtc_state->do_async_flip = true;
> + new_crtc_state->async_flip_planes |= BIT(plane->id);
> + }
>
> return 0;
> }
> diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c
> index 8d97c299e6577b..2ca7a016a9d9d1 100644
> --- a/drivers/gpu/drm/i915/display/intel_color.c
> +++ b/drivers/gpu/drm/i915/display/intel_color.c
> @@ -1500,12 +1500,15 @@ intel_color_add_affected_planes(struct intel_crtc_state *new_crtc_state)
> return PTR_ERR(plane_state);
>
> new_crtc_state->update_planes |= BIT(plane->id);
> + new_crtc_state->async_flip_planes = 0;
> + new_crtc_state->do_async_flip = false;
>
> /* plane control register changes blocked by CxSR */
> if (HAS_GMCH(i915))
> new_crtc_state->disable_cxsr = true;
> }
>
> +
> return 0;
> }
Thanks. Pushed now. I nuked that bogus extra newline while pushing.
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 717ca3d7890d34..fcd3f1c7af3291 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -1252,7 +1252,8 @@ static void intel_crtc_async_flip_disable_wa(struct intel_atomic_state *state,
> intel_atomic_get_old_crtc_state(state, crtc);
> const struct intel_crtc_state *new_crtc_state =
> intel_atomic_get_new_crtc_state(state, crtc);
> - u8 update_planes = new_crtc_state->update_planes;
> + u8 disable_async_flip_planes = old_crtc_state->async_flip_planes &
> + ~new_crtc_state->async_flip_planes;
> const struct intel_plane_state *old_plane_state;
> struct intel_plane *plane;
> bool need_vbl_wait = false;
> @@ -1261,7 +1262,7 @@ static void intel_crtc_async_flip_disable_wa(struct intel_atomic_state *state,
> for_each_old_intel_plane_in_state(state, plane, old_plane_state, i) {
> if (plane->need_async_flip_disable_wa &&
> plane->pipe == crtc->pipe &&
> - update_planes & BIT(plane->id)) {
> + disable_async_flip_planes & BIT(plane->id)) {
> /*
> * Apart from the async flip bit we want to
> * preserve the old state for the plane.
> @@ -1378,7 +1379,7 @@ static void intel_pre_plane_update(struct intel_atomic_state *state,
> * WA for platforms where async address update enable bit
> * is double buffered and only latched at start of vblank.
> */
> - if (old_crtc_state->uapi.async_flip && !new_crtc_state->uapi.async_flip)
> + if (old_crtc_state->async_flip_planes & ~new_crtc_state->async_flip_planes)
> intel_crtc_async_flip_disable_wa(state, crtc);
> }
>
> @@ -5939,6 +5940,8 @@ int intel_modeset_all_pipes(struct intel_atomic_state *state,
> return ret;
>
> crtc_state->update_planes |= crtc_state->active_planes;
> + crtc_state->async_flip_planes = 0;
> + crtc_state->do_async_flip = false;
> }
>
> return 0;
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 54c517ca9632fb..9ccae7a4602009 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1249,6 +1249,9 @@ struct intel_crtc_state {
> /* bitmask of planes that will be updated during the commit */
> u8 update_planes;
>
> + /* bitmask of planes with async flip active */
> + u8 async_flip_planes;
> +
> u8 framestart_delay; /* 1-4 */
> u8 msa_timing_delay; /* 0-3 */
>
> diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
> index ae4e9e680c2e30..261cdab390b484 100644
> --- a/drivers/gpu/drm/i915/display/skl_watermark.c
> +++ b/drivers/gpu/drm/i915/display/skl_watermark.c
> @@ -2397,6 +2397,8 @@ skl_ddb_add_affected_planes(const struct intel_crtc_state *old_crtc_state,
> return PTR_ERR(plane_state);
>
> new_crtc_state->update_planes |= BIT(plane_id);
> + new_crtc_state->async_flip_planes = 0;
> + new_crtc_state->do_async_flip = false;
> }
>
> return 0;
> @@ -2754,6 +2756,8 @@ static int skl_wm_add_affected_planes(struct intel_atomic_state *state,
> return PTR_ERR(plane_state);
>
> new_crtc_state->update_planes |= BIT(plane_id);
> + new_crtc_state->async_flip_planes = 0;
> + new_crtc_state->do_async_flip = false;
> }
>
> return 0;
> --
> 2.34.1
--
Ville Syrjälä
Intel
