Re: [PATCH v2 07/21] drm/i915/dp: Recheck link state after modeset

Imre Deak
2024-05-23T13:46:33Z

On Thu, May 23, 2024 at 04:30:18PM +0300, Ville Syrjälä wrote:
> On Mon, May 20, 2024 at 09:58:05PM +0300, Imre Deak wrote:
> > Recheck the link state after a passing link training, with a 2 sec delay
> > to account for cases where the link goes bad following the link training
> > and the sink doesn't report this via an HPD IRQ.
> >
> > The delayed work added here will be also used by a later patch after a
> > failed link training to try to retrain the link with unchanged link
> > params before reducing the link params.
> >
> > v2: Don't flush an uninitialized delayed work (on HDMI-only DDI ports).
> > v3: Add the work to intel_digital_port instead of intel_dp.
> >
> > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > ---
> > drivers/gpu/drm/i915/display/g4x_dp.c | 7 ++++
> > drivers/gpu/drm/i915/display/intel_ddi.c | 34 +++++++++++++++++++
> > drivers/gpu/drm/i915/display/intel_ddi.h | 4 +++
> > .../drm/i915/display/intel_display_types.h | 3 ++
> > drivers/gpu/drm/i915/display/intel_dp.c | 1 +
> > .../drm/i915/display/intel_dp_link_training.c | 12 +++++--
> > 6 files changed, 58 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/g4x_dp.c b/drivers/gpu/drm/i915/display/g4x_dp.c
> > index 06ec04e667e32..4363e32a834df 100644
> > --- a/drivers/gpu/drm/i915/display/g4x_dp.c
> > +++ b/drivers/gpu/drm/i915/display/g4x_dp.c
> > @@ -20,6 +20,7 @@
> > #include "intel_dp_aux.h"
> > #include "intel_dp_link_training.h"
> > #include "intel_dpio_phy.h"
> > +#include "intel_ddi.h"
> > #include "intel_fifo_underrun.h"
> > #include "intel_hdmi.h"
> > #include "intel_hotplug.h"
> > @@ -1241,6 +1242,10 @@ static bool ilk_digital_port_connected(struct intel_encoder *encoder)
> >
> > static void intel_dp_encoder_destroy(struct drm_encoder *encoder)
> > {
> > + struct intel_digital_port *dig_port = enc_to_dig_port(to_intel_encoder(encoder));
> > +
> > + intel_ddi_flush_link_check_work(dig_port);
> > +
> > intel_dp_encoder_flush_work(encoder);
> >
> > drm_encoder_cleanup(encoder);
> > @@ -1309,6 +1314,8 @@ bool g4x_dp_init(struct drm_i915_private *dev_priv,
> >
> > dig_port->aux_ch = AUX_CH_NONE;
> >
> > + intel_ddi_init_link_check_work(dig_port);
>
> Using "ddi" for pre-ddi platforms is confusing. The implementation
> is also in intel_ddi.c for some reason.

Yes. It's a generic encoder or digital port functionality, neither of
which have its own file. How about moving them to intel_display.c and
the intel_display_link_{init_work, queue_work, flush_work, work_fn}
names?

> > +
> > intel_connector = intel_connector_alloc();
> > if (!intel_connector)
> > goto err_connector_alloc;
> > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> > index 170ba01786cf8..86358ec27e685 100644
> > --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> > @@ -4360,6 +4360,7 @@ static void intel_ddi_encoder_destroy(struct drm_encoder *encoder)
> > struct drm_i915_private *i915 = to_i915(encoder->dev);
> > struct intel_digital_port *dig_port = enc_to_dig_port(to_intel_encoder(encoder));
> >
> > + intel_ddi_flush_link_check_work(dig_port);
> > intel_dp_encoder_flush_work(encoder);
> > if (intel_encoder_is_tc(&dig_port->base))
> > intel_tc_port_cleanup(dig_port);
> > @@ -4441,6 +4442,37 @@ intel_ddi_init_dp_connector(struct intel_digital_port *dig_port)
> > return connector;
> > }
> >
> > +static void intel_ddi_link_check_work_fn(struct work_struct *work)
> > +{
> > + struct intel_digital_port *dig_port =
> > + container_of(work, typeof(*dig_port), check_link_work.work);
> > + struct intel_encoder *encoder = &dig_port->base;
> > + struct drm_modeset_acquire_ctx ctx;
> > + int ret;
> > +
> > + intel_modeset_lock_ctx_retry(&ctx, NULL, 0, ret)
> > + if (dig_port->dp.attached_connector)
> > + ret = intel_dp_retrain_link(encoder, &ctx);
> > +}
> > +
> > +void intel_ddi_init_link_check_work(struct intel_digital_port *dig_port)
> > +{
> > + INIT_DELAYED_WORK(&dig_port->check_link_work, intel_ddi_link_check_work_fn);
> > +}
> > +
> > +void intel_ddi_flush_link_check_work(struct intel_digital_port *dig_port)
> > +{
> > + cancel_delayed_work_sync(&dig_port->check_link_work);
> > +}
> > +
> > +void intel_ddi_queue_link_check(struct intel_digital_port *dig_port, int delay_ms)
> > +{
> > + struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
> > +
> > + mod_delayed_work(i915->unordered_wq,
> > + &dig_port->check_link_work, msecs_to_jiffies(delay_ms));
> > +}
> > +
> > static int intel_hdmi_reset_link(struct intel_encoder *encoder,
> > struct drm_modeset_acquire_ctx *ctx)
> > {
> > @@ -4911,6 +4943,8 @@ void intel_ddi_init(struct drm_i915_private *dev_priv,
> >
> > dig_port->aux_ch = AUX_CH_NONE;
> >
> > + intel_ddi_init_link_check_work(dig_port);
> > +
> > encoder = &dig_port->base;
> > encoder->devdata = devdata;
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.h b/drivers/gpu/drm/i915/display/intel_ddi.h
> > index 434de7196875a..b67714483f3cc 100644
> > --- a/drivers/gpu/drm/i915/display/intel_ddi.h
> > +++ b/drivers/gpu/drm/i915/display/intel_ddi.h
> > @@ -15,6 +15,7 @@ struct intel_bios_encoder_data;
> > struct intel_connector;
> > struct intel_crtc;
> > struct intel_crtc_state;
> > +struct intel_digital_port;
> > struct intel_dp;
> > struct intel_dpll_hw_state;
> > struct intel_encoder;
> > @@ -53,6 +54,9 @@ void hsw_prepare_dp_ddi_buffers(struct intel_encoder *encoder,
> > const struct intel_crtc_state *crtc_state);
> > void intel_wait_ddi_buf_idle(struct drm_i915_private *dev_priv,
> > enum port port);
> > +void intel_ddi_init_link_check_work(struct intel_digital_port *dig_port);
> > +void intel_ddi_flush_link_check_work(struct intel_digital_port *dig_port);
> > +void intel_ddi_queue_link_check(struct intel_digital_port *dig_port, int delay_ms);
> > void intel_ddi_init(struct drm_i915_private *dev_priv,
> > const struct intel_bios_encoder_data *devdata);
> > bool intel_ddi_get_hw_state(struct intel_encoder *encoder, enum pipe *pipe);
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index 1e44a23ca2125..9317c1ae04efe 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1880,6 +1880,9 @@ struct intel_digital_port {
> >
> > struct intel_tc_port *tc;
> >
> > + /* Check and recover a bad link status on DP and HDMI ports. */
> > + struct delayed_work check_link_work;
> > +
> > /* protects num_hdcp_streams reference count, hdcp_port_data and hdcp_auth_status */
> > struct mutex hdcp_mutex;
> > /* the number of pipes using HDCP signalling out of this port */
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> > index 120f7b420807b..8da277f0c2735 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -75,6 +75,7 @@
> > #include "intel_hotplug_irq.h"
> > #include "intel_lspcon.h"
> > #include "intel_lvds.h"
> > +#include "intel_modeset_lock.h"
> > #include "intel_panel.h"
> > #include "intel_pch_display.h"
> > #include "intel_pps.h"
> > 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 edc970036866a..ad1fbb150ff90 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> > @@ -25,6 +25,7 @@
> > #include "intel_display_types.h"
> > #include "intel_dp.h"
> > #include "intel_dp_link_training.h"
> > +#include "intel_ddi.h"
> > #include "intel_panel.h"
> >
> > #define LT_MSG_PREFIX "[CONNECTOR:%d:%s][ENCODER:%d:%s][%s] "
> > @@ -1464,6 +1465,7 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp,
> > const struct intel_crtc_state *crtc_state)
> > {
> > struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> > + struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> > bool passed;
> >
> > /*
> > @@ -1483,6 +1485,11 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp,
> > else
> > passed = intel_dp_link_train_all_phys(intel_dp, crtc_state, lttpr_count);
> >
> > + if (passed) {
> > + intel_ddi_queue_link_check(dig_port, 2000);
> > + return;
> > + }
> > +
> > /*
> > * Ignore the link failure in CI
> > *
> > @@ -1495,13 +1502,12 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp,
> > * For test cases which rely on the link training or processing of HPDs
> > * ignore_long_hpd flag can unset from the testcase.
> > */
> > - if (!passed && i915->display.hotplug.ignore_long_hpd) {
> > + if (i915->display.hotplug.ignore_long_hpd) {
> > lt_dbg(intel_dp, DP_PHY_DPRX, "Ignore the link failure\n");
> > return;
> > }
> >
> > - if (!passed)
> > - intel_dp_schedule_fallback_link_training(intel_dp, crtc_state);
> > + intel_dp_schedule_fallback_link_training(intel_dp, crtc_state);
> > }
> >
> > void intel_dp_128b132b_sdp_crc16(struct intel_dp *intel_dp,
> > --
> > 2.43.3
>
> --
> Ville Syrjälä
> Intel