| Message ID | 1481252712-12925-1-git-send-email-manasi.d.navare@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 09 Dec 2016, Manasi Navare <manasi.d.navare@intel.com> wrote: > If link training fails, then we need to fallback to lower > link rate first and if link training fails at RBR, then > fallback to lower lane count. > This function finds the next lower link rate/lane count > value after link training failure and limits the max > link_rate and lane_count values to these fallback values. > > v7: > * Remove unnecessary intializations and remove redundant > call to intel_dp_common_rates (Jani Nikula) > v6: > * Cap the max link rate and lane count to the max > values obtained during fallback link training (Daniel Vetter) > v5: > * Start the fallback at the lane count value passed not > the max lane count (Jani Nikula) > v4: > * Remove the redundant variable link_train_failed > v3: > * Remove fallback_link_rate_index variable, just obtain > that using the helper intel_dp_link_rate_index (Jani Nikula) > v2: > Squash the patch that returns the link rate index (Jani Nikula) > > Acked-by: Tony Cheng <tony.cheng@amd.com> > Acked-by: Harry Wentland <harry.wentland@amd.com> > Cc: Ville Syrjala <ville.syrjala@linux.intel.com> > Cc: Jani Nikula <jani.nikula@linux.intel.com> > Cc: Daniel Vetter <daniel.vetter@intel.com> > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> > --- > drivers/gpu/drm/i915/intel_dp.c | 38 ++++++++++++++++++++++++++++++++++++++ > drivers/gpu/drm/i915/intel_drv.h | 2 ++ > 2 files changed, 40 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c > index 434dc7d..1b5e0d0 100644 > --- a/drivers/gpu/drm/i915/intel_dp.c > +++ b/drivers/gpu/drm/i915/intel_dp.c > @@ -278,6 +278,44 @@ static int intel_dp_common_rates(struct intel_dp *intel_dp, > common_rates); > } > > +static int intel_dp_link_rate_index(struct intel_dp *intel_dp, > + int *common_rates, int link_rate) > +{ > + int common_len; > + int index; > + > + common_len = intel_dp_common_rates(intel_dp, common_rates); > + for (index = 0; index < common_len; index++) { > + if (link_rate == common_rates[common_len - index - 1]) > + return common_len - index - 1; > + } > + > + return -1; > +} > + > +int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, > + int link_rate, uint8_t lane_count) > +{ > + int common_rates[DP_MAX_SUPPORTED_RATES]; > + int link_rate_index; > + > + link_rate_index = intel_dp_link_rate_index(intel_dp, > + common_rates, > + link_rate); > + if (link_rate_index > 0) { > + intel_dp->max_sink_link_bw = drm_dp_link_rate_to_bw_code(common_rates[link_rate_index - 1]); > + intel_dp->max_sink_lane_count = lane_count; > + } else if (lane_count > 1) { > + intel_dp->max_sink_link_bw = intel_dp_max_link_bw(intel_dp); > + intel_dp->max_sink_lane_count = lane_count >> 1; > + } else { > + DRM_ERROR("Link Training Unsuccessful\n"); > + return -1; > + } > + > + return 0; > +} > + > static enum drm_mode_status > intel_dp_mode_valid(struct drm_connector *connector, > struct drm_display_mode *mode) > diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h > index 377693e..0a20422 100644 > --- a/drivers/gpu/drm/i915/intel_drv.h > +++ b/drivers/gpu/drm/i915/intel_drv.h > @@ -1400,6 +1400,8 @@ bool intel_dp_init_connector(struct intel_digital_port *intel_dig_port, > void intel_dp_set_link_params(struct intel_dp *intel_dp, > int link_rate, uint8_t lane_count, > bool link_mst); > +int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, > + int link_rate, uint8_t lane_count); > void intel_dp_start_link_train(struct intel_dp *intel_dp); > void intel_dp_stop_link_train(struct intel_dp *intel_dp); > void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode);
On Fri, 09 Dec 2016, Jani Nikula <jani.nikula@linux.intel.com> wrote: > On Fri, 09 Dec 2016, Manasi Navare <manasi.d.navare@intel.com> wrote: >> If link training fails, then we need to fallback to lower >> link rate first and if link training fails at RBR, then >> fallback to lower lane count. >> This function finds the next lower link rate/lane count >> value after link training failure and limits the max >> link_rate and lane_count values to these fallback values. >> >> v7: >> * Remove unnecessary intializations and remove redundant >> call to intel_dp_common_rates (Jani Nikula) >> v6: >> * Cap the max link rate and lane count to the max >> values obtained during fallback link training (Daniel Vetter) >> v5: >> * Start the fallback at the lane count value passed not >> the max lane count (Jani Nikula) >> v4: >> * Remove the redundant variable link_train_failed >> v3: >> * Remove fallback_link_rate_index variable, just obtain >> that using the helper intel_dp_link_rate_index (Jani Nikula) >> v2: >> Squash the patch that returns the link rate index (Jani Nikula) >> >> Acked-by: Tony Cheng <tony.cheng@amd.com> >> Acked-by: Harry Wentland <harry.wentland@amd.com> >> Cc: Ville Syrjala <ville.syrjala@linux.intel.com> >> Cc: Jani Nikula <jani.nikula@linux.intel.com> >> Cc: Daniel Vetter <daniel.vetter@intel.com> >> Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> > > Reviewed-by: Jani Nikula <jani.nikula@intel.com> And pushed this one to dinq, thanks for the patch. BR, Jani. > > >> --- >> drivers/gpu/drm/i915/intel_dp.c | 38 ++++++++++++++++++++++++++++++++++++++ >> drivers/gpu/drm/i915/intel_drv.h | 2 ++ >> 2 files changed, 40 insertions(+) >> >> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c >> index 434dc7d..1b5e0d0 100644 >> --- a/drivers/gpu/drm/i915/intel_dp.c >> +++ b/drivers/gpu/drm/i915/intel_dp.c >> @@ -278,6 +278,44 @@ static int intel_dp_common_rates(struct intel_dp *intel_dp, >> common_rates); >> } >> >> +static int intel_dp_link_rate_index(struct intel_dp *intel_dp, >> + int *common_rates, int link_rate) >> +{ >> + int common_len; >> + int index; >> + >> + common_len = intel_dp_common_rates(intel_dp, common_rates); >> + for (index = 0; index < common_len; index++) { >> + if (link_rate == common_rates[common_len - index - 1]) >> + return common_len - index - 1; >> + } >> + >> + return -1; >> +} >> + >> +int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, >> + int link_rate, uint8_t lane_count) >> +{ >> + int common_rates[DP_MAX_SUPPORTED_RATES]; >> + int link_rate_index; >> + >> + link_rate_index = intel_dp_link_rate_index(intel_dp, >> + common_rates, >> + link_rate); >> + if (link_rate_index > 0) { >> + intel_dp->max_sink_link_bw = drm_dp_link_rate_to_bw_code(common_rates[link_rate_index - 1]); >> + intel_dp->max_sink_lane_count = lane_count; >> + } else if (lane_count > 1) { >> + intel_dp->max_sink_link_bw = intel_dp_max_link_bw(intel_dp); >> + intel_dp->max_sink_lane_count = lane_count >> 1; >> + } else { >> + DRM_ERROR("Link Training Unsuccessful\n"); >> + return -1; >> + } >> + >> + return 0; >> +} >> + >> static enum drm_mode_status >> intel_dp_mode_valid(struct drm_connector *connector, >> struct drm_display_mode *mode) >> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h >> index 377693e..0a20422 100644 >> --- a/drivers/gpu/drm/i915/intel_drv.h >> +++ b/drivers/gpu/drm/i915/intel_drv.h >> @@ -1400,6 +1400,8 @@ bool intel_dp_init_connector(struct intel_digital_port *intel_dig_port, >> void intel_dp_set_link_params(struct intel_dp *intel_dp, >> int link_rate, uint8_t lane_count, >> bool link_mst); >> +int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, >> + int link_rate, uint8_t lane_count); >> void intel_dp_start_link_train(struct intel_dp *intel_dp); >> void intel_dp_stop_link_train(struct intel_dp *intel_dp); >> void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode);
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 434dc7d..1b5e0d0 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -278,6 +278,44 @@ static int intel_dp_common_rates(struct intel_dp *intel_dp, common_rates); } +static int intel_dp_link_rate_index(struct intel_dp *intel_dp, + int *common_rates, int link_rate) +{ + int common_len; + int index; + + common_len = intel_dp_common_rates(intel_dp, common_rates); + for (index = 0; index < common_len; index++) { + if (link_rate == common_rates[common_len - index - 1]) + return common_len - index - 1; + } + + return -1; +} + +int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, + int link_rate, uint8_t lane_count) +{ + int common_rates[DP_MAX_SUPPORTED_RATES]; + int link_rate_index; + + link_rate_index = intel_dp_link_rate_index(intel_dp, + common_rates, + link_rate); + if (link_rate_index > 0) { + intel_dp->max_sink_link_bw = drm_dp_link_rate_to_bw_code(common_rates[link_rate_index - 1]); + intel_dp->max_sink_lane_count = lane_count; + } else if (lane_count > 1) { + intel_dp->max_sink_link_bw = intel_dp_max_link_bw(intel_dp); + intel_dp->max_sink_lane_count = lane_count >> 1; + } else { + DRM_ERROR("Link Training Unsuccessful\n"); + return -1; + } + + return 0; +} + static enum drm_mode_status intel_dp_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode) diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 377693e..0a20422 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1400,6 +1400,8 @@ bool intel_dp_init_connector(struct intel_digital_port *intel_dig_port, void intel_dp_set_link_params(struct intel_dp *intel_dp, int link_rate, uint8_t lane_count, bool link_mst); +int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, + int link_rate, uint8_t lane_count); void intel_dp_start_link_train(struct intel_dp *intel_dp); void intel_dp_stop_link_train(struct intel_dp *intel_dp); void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode);