On Tue, Oct 19, 2021 at 10:23:14PM +0300, Jani Nikula wrote: > On Mon, 18 Oct 2021, Imre Deak <[email protected]> wrote: > > Add an assert that lookups from the intel_dp->common_rates[] array > > are always valid. > > The one thought I had here was that if we're adding helper functions for > accessing common rates, they should probably be of the form "this is the > rate I have now, give me a slower rate" instead of making the index part > of the interface. The index doesn't really mean anything, and if we want > to avoid overflows, it should be hidden from the interfaces.
intel_dp_rate_index() is also part of the interface, but I suppose it could be improved. > But again, can be follow-up. > > BR, > Jani. > > > > > > Cc: Ville Syrjälä <[email protected]> > > Signed-off-by: Imre Deak <[email protected]> > > --- > > drivers/gpu/drm/i915/display/intel_dp.c | 33 ++++++++++++------------- > > 1 file changed, 16 insertions(+), 17 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > > b/drivers/gpu/drm/i915/display/intel_dp.c > > index f8082eb8e7263..3869d454c10f0 100644 > > --- a/drivers/gpu/drm/i915/display/intel_dp.c > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > > @@ -267,10 +267,19 @@ static int intel_dp_common_len_rate_limit(const > > struct intel_dp *intel_dp, > > intel_dp->num_common_rates, max_rate); > > } > > > > +static int intel_dp_common_rate(struct intel_dp *intel_dp, int index) > > +{ > > + if (drm_WARN_ON(&dp_to_i915(intel_dp)->drm, > > + index < 0 || index >= intel_dp->num_common_rates)) > > + return 162000; > > + > > + return intel_dp->common_rates[index]; > > +} > > + > > /* Theoretical max between source and sink */ > > static int intel_dp_max_common_rate(struct intel_dp *intel_dp) > > { > > - return intel_dp->common_rates[intel_dp->num_common_rates - 1]; > > + return intel_dp_common_rate(intel_dp, intel_dp->num_common_rates - 1); > > } > > > > /* Theoretical max between source and sink */ > > @@ -610,13 +619,13 @@ int intel_dp_get_link_train_fallback_values(struct > > intel_dp *intel_dp, > > if (index > 0) { > > if (intel_dp_is_edp(intel_dp) && > > !intel_dp_can_link_train_fallback_for_edp(intel_dp, > > - > > intel_dp->common_rates[index - 1], > > + > > intel_dp_common_rate(intel_dp, index - 1), > > lane_count)) { > > drm_dbg_kms(&i915->drm, > > "Retrying Link training for eDP with same > > parameters\n"); > > return 0; > > } > > - intel_dp->max_link_rate = intel_dp->common_rates[index - 1]; > > + intel_dp->max_link_rate = intel_dp_common_rate(intel_dp, index > > - 1); > > intel_dp->max_link_lane_count = lane_count; > > } else if (lane_count > 1) { > > if (intel_dp_is_edp(intel_dp) && > > @@ -1056,14 +1065,11 @@ static void intel_dp_print_rates(struct intel_dp > > *intel_dp) > > int > > intel_dp_max_link_rate(struct intel_dp *intel_dp) > > { > > - struct drm_i915_private *i915 = dp_to_i915(intel_dp); > > int len; > > > > len = intel_dp_common_len_rate_limit(intel_dp, intel_dp->max_link_rate); > > - if (drm_WARN_ON(&i915->drm, len <= 0)) > > - return 162000; > > > > - return intel_dp->common_rates[len - 1]; > > + return intel_dp_common_rate(intel_dp, len - 1); > > } > > > > int intel_dp_rate_select(struct intel_dp *intel_dp, int rate) > > @@ -1260,7 +1266,7 @@ intel_dp_compute_link_config_wide(struct intel_dp > > *intel_dp, > > output_bpp); > > > > for (i = 0; i < intel_dp->num_common_rates; i++) { > > - link_rate = intel_dp->common_rates[i]; > > + link_rate = intel_dp_common_rate(intel_dp, i); > > if (link_rate < limits->min_rate || > > link_rate > limits->max_rate) > > continue; > > @@ -1508,17 +1514,10 @@ intel_dp_compute_link_config(struct intel_encoder > > *encoder, > > &pipe_config->hw.adjusted_mode; > > struct intel_dp *intel_dp = enc_to_intel_dp(encoder); > > struct link_config_limits limits; > > - int common_len; > > int ret; > > > > - common_len = intel_dp_common_len_rate_limit(intel_dp, > > - intel_dp->max_link_rate); > > - > > - /* No common link rates between source and sink */ > > - drm_WARN_ON(encoder->base.dev, common_len <= 0); > > - > > - limits.min_rate = intel_dp->common_rates[0]; > > - limits.max_rate = intel_dp->common_rates[common_len - 1]; > > + limits.min_rate = intel_dp_common_rate(intel_dp, 0); > > + limits.max_rate = intel_dp_max_link_rate(intel_dp); > > > > limits.min_lane_count = 1; > > limits.max_lane_count = intel_dp_max_lane_count(intel_dp); > > -- > Jani Nikula, Intel Open Source Graphics Center
