[PATCH v2 11/21] drm/i915/dp: Add way to get active pipes with syncing commits

[Shankar, Uma]

> -----Original Message-----
> From: dri-devel <dri-devel-bounces at lists.freedesktop.org> On Behalf Of Imre
> Deak
> Sent: Wednesday, February 21, 2024 2:49 AM
> To: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Subject: [PATCH v2 11/21] drm/i915/dp: Add way to get active pipes with syncing
> commits
> 
> Add a way to get the active pipes through a given DP port by syncing against a
> related pending non-blocking commit. Atm
> intel_dp_get_active_pipes() will only try to sync a given pipe and if that would
> block ignore the pipe. A follow-up change enabling the DP tunnel BW allocation
> mode will need to ensure that all active pipes are returned.
> 
> This change will use intel_crtc_state::uapi.commit instead of the corresponding
> commit in the connector state. This shouldn't make a difference, since the two
> commit objects match for an active pipe.
> 
> A follow-up patchset will remove syncing during TC port reset, which should reset
> a port/pipe even if syncing against a commit would block.
> Syncing OTOH is not needed there, since the commit used for the reset implies a
> sync already. For now add a TODO comment for this.
> 
> v2:
> - Add a separate function to try-sync the pipes. (Ville)

Looks Good to me.
Reviewed-by: Uma Shankar <uma.shankar at intel.com>

> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_crtc.c | 27 +++++++++++++++++++++++
> drivers/gpu/drm/i915/display/intel_crtc.h |  1 +
>  drivers/gpu/drm/i915/display/intel_dp.c   |  6 ++---
>  drivers/gpu/drm/i915/display/intel_tc.c   |  7 ++++++
>  4 files changed, 37 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c
> b/drivers/gpu/drm/i915/display/intel_crtc.c
> index 25593f6aae7de..17ed2e62cc66a 100644
> --- a/drivers/gpu/drm/i915/display/intel_crtc.c
> +++ b/drivers/gpu/drm/i915/display/intel_crtc.c
> @@ -654,3 +654,30 @@ void intel_pipe_update_end(struct intel_atomic_state
> *state,
>  out:
>  	intel_psr_unlock(new_crtc_state);
>  }
> +
> +/**
> + * intel_crtc_try_sync_pipes - Try syncing pending commits on a set of
> +pipes
> + * @i915: i915 device object
> + * @pipe_mask: Mask of pipes to sync
> + *
> + * Try to sync a pending non-blocking commit for the provided pipes in
> + * @pipe_mask. The commit won't be synced if this would block.
> + *
> + * Return a mask of the pipes that got synced or didn't need syncing.
> + */
> +u32 intel_crtc_try_sync_pipes(struct drm_i915_private *i915, u32
> +pipe_mask) {
> +	struct intel_crtc *crtc;
> +	u32 synced = 0;
> +
> +	for_each_intel_crtc_in_pipe_mask(&i915->drm, crtc, pipe_mask) {
> +		const struct intel_crtc_state *crtc_state =
> +			to_intel_crtc_state(crtc->base.state);
> +
> +		if (!crtc_state->uapi.commit ||
> +		    try_wait_for_completion(&crtc_state->uapi.commit-
> >hw_done))
> +			synced |= BIT(crtc->pipe);
> +	}
> +
> +	return synced;
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_crtc.h
> b/drivers/gpu/drm/i915/display/intel_crtc.h
> index 22d7993d1f0ba..71a5b93166da7 100644
> --- a/drivers/gpu/drm/i915/display/intel_crtc.h
> +++ b/drivers/gpu/drm/i915/display/intel_crtc.h
> @@ -47,5 +47,6 @@ struct intel_crtc *intel_crtc_for_pipe(struct
> drm_i915_private *i915,  void intel_wait_for_vblank_if_active(struct
> drm_i915_private *i915,
>  				     enum pipe pipe);
>  void intel_crtc_wait_for_next_vblank(struct intel_crtc *crtc);
> +u32 intel_crtc_try_sync_pipes(struct drm_i915_private *i915, u32
> +pipe_mask);
> 
>  #endif
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index d9e75922ff8f5..d0452d3e534a7 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -5048,10 +5048,6 @@ int intel_dp_get_active_pipes(struct intel_dp
> *intel_dp,
>  		if (!crtc_state->hw.active)
>  			continue;
> 
> -		if (conn_state->commit &&
> -		    !try_wait_for_completion(&conn_state->commit->hw_done))
> -			continue;
> -
>  		*pipe_mask |= BIT(crtc->pipe);
>  	}
>  	drm_connector_list_iter_end(&conn_iter);
> @@ -5091,6 +5087,8 @@ int intel_dp_retrain_link(struct intel_encoder
> *encoder,
>  	if (ret)
>  		return ret;
> 
> +	pipe_mask &= intel_crtc_try_sync_pipes(dev_priv, pipe_mask);
> +
>  	if (pipe_mask == 0)
>  		return 0;
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_tc.c
> b/drivers/gpu/drm/i915/display/intel_tc.c
> index 6b374d481cd9e..14d17903a81f5 100644
> --- a/drivers/gpu/drm/i915/display/intel_tc.c
> +++ b/drivers/gpu/drm/i915/display/intel_tc.c
> @@ -7,6 +7,7 @@
>  #include "i915_reg.h"
>  #include "intel_atomic.h"
>  #include "intel_cx0_phy_regs.h"
> +#include "intel_crtc.h"
>  #include "intel_ddi.h"
>  #include "intel_de.h"
>  #include "intel_display.h"
> @@ -1663,6 +1664,12 @@ static int reset_link_commit(struct intel_tc_port *tc,
>  	if (ret)
>  		return ret;
> 
> +	/*
> +	 * TODO: remove the following, since an output must be reset
> +	 * even if we had to wait for a non-blocking commit on a pipe.
> +	 */
> +	pipe_mask &= intel_crtc_try_sync_pipes(i915, pipe_mask);
> +
>  	if (!pipe_mask)
>  		return 0;
> 
> --
> 2.39.2