On Mon, May 18, 2026 at 02:24:22PM +0300, Imre Deak wrote:
> Add helpers to defer and handle link params resets instead of
> open-coding the same. Rename intel_dp_reset_link_params() to
> intel_dp_reset_link_params_force() to align its name with the new
> deferred reset helpers.
>
> When deferring a reset, return whether a new reset was queued, used by a
> follow-up change.
>
> Signed-off-by: Imre Deak <[email protected]>
> ---
> drivers/gpu/drm/i915/display/g4x_dp.c | 2 +-
> drivers/gpu/drm/i915/display/intel_ddi.c | 2 +-
> drivers/gpu/drm/i915/display/intel_dp.c | 41 +++++++++++++++----
> drivers/gpu/drm/i915/display/intel_dp.h | 3 +-
> .../drm/i915/display/intel_dp_link_training.c | 4 +-
> 5 files changed, 38 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/g4x_dp.c
> b/drivers/gpu/drm/i915/display/g4x_dp.c
> index 5ff1cdf4581a5..c20a97e21419b 100644
> --- a/drivers/gpu/drm/i915/display/g4x_dp.c
> +++ b/drivers/gpu/drm/i915/display/g4x_dp.c
> @@ -1265,7 +1265,7 @@ static void intel_dp_encoder_reset(struct drm_encoder
> *encoder)
>
> intel_dp->DP = intel_de_read(display, intel_dp->output_reg);
>
> - intel_dp->reset_link_params = true;
> + intel_dp_reset_link_params_defer(intel_dp);
> intel_dp_invalidate_source_oui(intel_dp);
>
> if (display->platform.valleyview || display->platform.cherryview)
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c
> b/drivers/gpu/drm/i915/display/intel_ddi.c
> index 86520848892e0..77819aaeccb76 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -4664,7 +4664,7 @@ static void intel_ddi_encoder_reset(struct drm_encoder
> *encoder)
> struct intel_dp *intel_dp = enc_to_intel_dp(to_intel_encoder(encoder));
> struct intel_digital_port *dig_port =
> enc_to_dig_port(to_intel_encoder(encoder));
>
> - intel_dp->reset_link_params = true;
> + intel_dp_reset_link_params_defer(intel_dp);
> intel_dp_invalidate_source_oui(intel_dp);
>
> intel_pps_encoder_reset(intel_dp);
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index 1920d2f026665..13163dd085e91 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -3710,7 +3710,11 @@ void intel_dp_set_link_params(struct intel_dp
> *intel_dp,
> intel_dp->lane_count = lane_count;
> }
>
> -void intel_dp_reset_link_params(struct intel_dp *intel_dp)
> +/*
> + * Reset link params now, preserving any deferred connector
> + * detect-time reset request.
> + */
> +void intel_dp_reset_link_params_force(struct intel_dp *intel_dp)
> {
> intel_dp->link.max_lane_count =
> intel_dp_max_common_lane_count(intel_dp);
> intel_dp->link.max_rate = intel_dp_max_common_rate(intel_dp);
> @@ -3720,6 +3724,28 @@ void intel_dp_reset_link_params(struct intel_dp
> *intel_dp)
> intel_dp->link.seq_train_failures = 0;
> }
>
> +/*
> + * Reset link params during the next connector detect.
> + * Return %true if a new reset was queued.
> + */
> +bool intel_dp_reset_link_params_defer(struct intel_dp *intel_dp)
I find the intel_dp_reset_link_params_defer() vs.
intel_dp_reset_link_params_force() naming rather confusing.
Can't immediately think of a really good name for
intel_dp_reset_link_params_defer() so maybe it's better to not
have a function for it at all (ie. just drop this patch)? Then
you at least see that it's just setting the flag. AFAICS you
only have a single place (in the last patch) that uses this
return value for anything, so could just do the check+set
dance there on the spot.
> +{
> + bool reset_was_pending = intel_dp->reset_link_params;
> +
> + intel_dp->reset_link_params = true;
> +
> + return !reset_was_pending;
> +}
> +
> +static void intel_dp_handle_deferred_link_params_reset(struct intel_dp
> *intel_dp)
> +{
> + if (!intel_dp->reset_link_params)
> + return;
> +
> + intel_dp->reset_link_params = false;
> + intel_dp_reset_link_params_force(intel_dp);
> +}
> +
> /* Enable backlight PWM and backlight PP control. */
> void intel_edp_backlight_on(const struct intel_crtc_state *crtc_state,
> const struct drm_connector_state *conn_state)
> @@ -4066,7 +4092,7 @@ void intel_dp_sync_state(struct intel_encoder *encoder,
> intel_dp_tunnel_resume(intel_dp, crtc_state, dpcd_updated);
>
> if (crtc_state) {
> - intel_dp_reset_link_params(intel_dp);
> + intel_dp_reset_link_params_force(intel_dp);
> intel_dp_set_link_params(intel_dp, crtc_state->port_clock,
> crtc_state->lane_count);
> intel_dp->link.active = true;
> }
> @@ -6487,10 +6513,7 @@ intel_dp_detect(struct drm_connector *_connector,
>
> intel_dp_detect_sdp_caps(intel_dp);
>
> - if (intel_dp->reset_link_params) {
> - intel_dp_reset_link_params(intel_dp);
> - intel_dp->reset_link_params = false;
> - }
> + intel_dp_handle_deferred_link_params_reset(intel_dp);
>
> intel_dp_mst_configure(intel_dp);
>
> @@ -6944,7 +6967,7 @@ intel_dp_hpd_pulse(struct intel_digital_port *dig_port,
> bool long_hpd)
>
> intel_dp_read_dprx_caps(intel_dp, dpcd);
>
> - intel_dp->reset_link_params = true;
> + intel_dp_reset_link_params_defer(intel_dp);
> intel_dp_invalidate_source_oui(intel_dp);
>
> return IRQ_NONE;
> @@ -7252,7 +7275,7 @@ intel_dp_init_connector(struct intel_digital_port
> *dig_port,
> encoder->base.name))
> return false;
>
> - intel_dp->reset_link_params = true;
> + intel_dp_reset_link_params_defer(intel_dp);
>
> /* Preserve the current hw state. */
> intel_dp->DP = intel_de_read(display, intel_dp->output_reg);
> @@ -7317,7 +7340,7 @@ intel_dp_init_connector(struct intel_digital_port
> *dig_port,
>
> intel_dp_set_source_rates(intel_dp);
> intel_dp_set_common_rates(intel_dp);
> - intel_dp_reset_link_params(intel_dp);
> + intel_dp_reset_link_params_force(intel_dp);
>
> /* init MST on ports that can support it */
> intel_dp_mst_encoder_init(dig_port, connector->base.base.id);
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.h
> b/drivers/gpu/drm/i915/display/intel_dp.h
> index f41480d247142..7c24d3dbb6983 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.h
> +++ b/drivers/gpu/drm/i915/display/intel_dp.h
> @@ -114,7 +114,8 @@ int intel_dp_rate_index(const int *rates, int len, int
> rate);
> int intel_dp_link_config_index(struct intel_dp *intel_dp, int link_rate, int
> lane_count);
> void intel_dp_link_config_get(struct intel_dp *intel_dp, int idx, int
> *link_rate, int *lane_count);
> void intel_dp_update_sink_caps(struct intel_dp *intel_dp);
> -void intel_dp_reset_link_params(struct intel_dp *intel_dp);
> +void intel_dp_reset_link_params_force(struct intel_dp *intel_dp);
> +bool intel_dp_reset_link_params_defer(struct intel_dp *intel_dp);
>
> void intel_dp_compute_rate(struct intel_dp *intel_dp, int port_clock,
> u8 *link_bw, u8 *rate_select);
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> index a26094223f780..b7075060e7bd3 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> @@ -1935,7 +1935,7 @@ static ssize_t i915_dp_force_link_rate_write(struct
> file *file,
> if (err)
> return err;
>
> - intel_dp_reset_link_params(intel_dp);
> + intel_dp_reset_link_params_force(intel_dp);
> intel_dp->link.force_rate = rate;
>
> drm_modeset_unlock(&display->drm->mode_config.connection_mutex);
> @@ -2037,7 +2037,7 @@ static ssize_t i915_dp_force_lane_count_write(struct
> file *file,
> if (err)
> return err;
>
> - intel_dp_reset_link_params(intel_dp);
> + intel_dp_reset_link_params_force(intel_dp);
> intel_dp->link.force_lane_count = lane_count;
>
> drm_modeset_unlock(&display->drm->mode_config.connection_mutex);
> --
> 2.49.1
--
Ville Syrjälä
Intel
