On Tue, Oct 01, 2024 at 04:01:55PM +0300, Jani Nikula wrote: > On Tue, 01 Oct 2024, Imre Deak <imre.deak@xxxxxxxxx> wrote: > > While updating the source OUI on the sink the driver should avoid > > writing the OUI if it's already up-to-date to prevent the sink from > > resetting itself in response to the update. On eDP - the only output > > type where the OUI was updated so far - the driver ensured this by > > comparing the current source OUI DPCD register values with the expected > > Intel OUI value, skipping the update in case of a match. On some non-eDP > > sinks - at least on Synaptics branch devices - this method doesn't work, > > since the source OUI DPCD registers read back as all 0, even after > > updating the registers. > > > > Handle the above kind of sinks by tracking when the OUI was updated and > > so should be valid, regardless of what the DPCD registers contain. > > > > This is required by the next patch updating the source OUI on non-eDP > > sink types as well. > > > > Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> > > --- > > drivers/gpu/drm/i915/display/g4x_dp.c | 1 + > > drivers/gpu/drm/i915/display/intel_ddi.c | 1 + > > .../drm/i915/display/intel_display_types.h | 1 + > > drivers/gpu/drm/i915/display/intel_dp.c | 25 ++++++++++++++----- > > drivers/gpu/drm/i915/display/intel_dp.h | 1 + > > 5 files changed, 23 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/g4x_dp.c b/drivers/gpu/drm/i915/display/g4x_dp.c > > index 440fb3002f286..596e926ef0894 100644 > > --- a/drivers/gpu/drm/i915/display/g4x_dp.c > > +++ b/drivers/gpu/drm/i915/display/g4x_dp.c > > @@ -1251,6 +1251,7 @@ 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_invalidate_source_oui(intel_dp); > > > > if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) > > vlv_pps_pipe_reset(intel_dp); > > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c > > index fe1ded6707f90..465f245a53c48 100644 > > --- a/drivers/gpu/drm/i915/display/intel_ddi.c > > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c > > @@ -4392,6 +4392,7 @@ static void intel_ddi_encoder_reset(struct drm_encoder *encoder) > > struct intel_digital_port *dig_port = enc_to_dig_port(to_intel_encoder(encoder)); > > > > intel_dp->reset_link_params = true; > > + intel_dp_invalidate_source_oui(intel_dp); > > > > intel_pps_encoder_reset(intel_dp); > > > > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h > > index 7ff97e5b83dd5..ad84ffa31c97f 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display_types.h > > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h > > @@ -1757,6 +1757,7 @@ struct intel_dp { > > > > /* When we last wrote the OUI for eDP */ > > unsigned long last_oui_write; > > + bool oui_valid; > > > > bool colorimetry_support; > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c > > index b7661529f1927..2d6ffbeae07a0 100644 > > --- a/drivers/gpu/drm/i915/display/intel_dp.c > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > > @@ -3335,31 +3335,43 @@ void intel_dp_sink_disable_decompression(struct intel_atomic_state *state, > > } > > > > static void > > -intel_edp_init_source_oui(struct intel_dp *intel_dp, bool careful) > > +intel_dp_init_source_oui(struct intel_dp *intel_dp) > > { > > struct drm_i915_private *i915 = dp_to_i915(intel_dp); > > u8 oui[] = { 0x00, 0xaa, 0x01 }; > > u8 buf[3] = {}; > > > > + if (!intel_dp_is_edp(intel_dp)) > > + return; > > + > > /* > > * During driver init, we want to be careful and avoid changing the source OUI if it's > > * already set to what we want, so as to avoid clearing any state by accident > > */ > > - if (careful) { > > + if (!intel_dp->oui_valid) { > > if (drm_dp_dpcd_read(&intel_dp->aux, DP_SOURCE_OUI, buf, sizeof(buf)) < 0) > > drm_err(&i915->drm, "Failed to read source OUI\n"); > > > > if (memcmp(oui, buf, sizeof(oui)) == 0) { > > /* Assume the OUI was written now. */ > > intel_dp->last_oui_write = jiffies; > > - return; > > + intel_dp->oui_valid = true; > > } > > } > > > > + if (intel_dp->oui_valid) > > + return; > > + > > if (drm_dp_dpcd_write(&intel_dp->aux, DP_SOURCE_OUI, oui, sizeof(oui)) < 0) > > drm_err(&i915->drm, "Failed to write source OUI\n"); > > > > intel_dp->last_oui_write = jiffies; > > + intel_dp->oui_valid = true; > > Looking at patches 1 and 2, I'm thinking we don't need two members for > this. > > Just make intel_dp->last_oui_write == 0 mean "invalid". 0 is a valid jiffies value and then 0 shouldn't be used when setting last_oui_write. Not sure if that's better. > > BR, > Jani. > > > > +} > > + > > +void intel_dp_invalidate_source_oui(struct intel_dp *intel_dp) > > +{ > > + intel_dp->oui_valid = false; > > } > > > > void intel_dp_wait_source_oui(struct intel_dp *intel_dp) > > @@ -3390,6 +3402,8 @@ void intel_dp_set_power(struct intel_dp *intel_dp, u8 mode) > > if (downstream_hpd_needs_d0(intel_dp)) > > return; > > > > + intel_dp_invalidate_source_oui(intel_dp); > > + > > ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER, mode); > > } else { > > struct intel_lspcon *lspcon = dp_to_lspcon(intel_dp); > > @@ -3397,8 +3411,7 @@ void intel_dp_set_power(struct intel_dp *intel_dp, u8 mode) > > lspcon_resume(dp_to_dig_port(intel_dp)); > > > > /* Write the source OUI as early as possible */ > > - if (intel_dp_is_edp(intel_dp)) > > - intel_edp_init_source_oui(intel_dp, false); > > + intel_dp_init_source_oui(intel_dp); > > > > /* > > * When turning on, we need to retry for 1ms to give the sink > > @@ -4115,7 +4128,7 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp, struct intel_connector *connector > > * If needed, program our source OUI so we can make various Intel-specific AUX services > > * available (such as HDR backlight controls) > > */ > > - intel_edp_init_source_oui(intel_dp, true); > > + intel_dp_init_source_oui(intel_dp); > > > > return true; > > } > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h > > index 3b869429e5756..0449d1d3f175d 100644 > > --- a/drivers/gpu/drm/i915/display/intel_dp.h > > +++ b/drivers/gpu/drm/i915/display/intel_dp.h > > @@ -189,6 +189,7 @@ void intel_dp_check_frl_training(struct intel_dp *intel_dp); > > void intel_dp_pcon_dsc_configure(struct intel_dp *intel_dp, > > const struct intel_crtc_state *crtc_state); > > > > +void intel_dp_invalidate_source_oui(struct intel_dp *intel_dp); > > void intel_dp_wait_source_oui(struct intel_dp *intel_dp); > > int intel_dp_output_bpp(enum intel_output_format output_format, int bpp); > > -- > Jani Nikula, Intel