On Wed, 01 Jun 2022, Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> wrote:
> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>
> We're not parsing the 5.4 Gbps value for the old eDP fast link
> training link rate, nor are we parsing the new fast link training
> link rate field. Remedy both.
>
> Note that we're not even using this information for anything
> currently, so should perhaps just nuke it all unless someone
> is planning on implementing fast link training finally...
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_bios.c | 32 ++++++++++++-------
> drivers/gpu/drm/i915/display/intel_vbt_defs.h | 1 +
> 2 files changed, 21 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
> index c42b9e7d0dce..d701854dc429 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -1367,18 +1367,26 @@ parse_edp(struct drm_i915_private *i915,
>
> panel->vbt.edp.pps = *edp_pps;
>
> - switch (edp_link_params->rate) {
> - case EDP_RATE_1_62:
> - panel->vbt.edp.rate = DP_LINK_BW_1_62;
> - break;
> - case EDP_RATE_2_7:
> - panel->vbt.edp.rate = DP_LINK_BW_2_7;
> - break;
> - default:
> - drm_dbg_kms(&i915->drm,
> - "VBT has unknown eDP link rate value %u\n",
> - edp_link_params->rate);
> - break;
> + if (i915->vbt.version >= 224) {
> + panel->vbt.edp.rate =
> + edp->edp_fast_link_training_rate[panel_type] * 2;
So this is in units of 200 kHz.
> + } else {
> + switch (edp_link_params->rate) {
> + case EDP_RATE_1_62:
> + panel->vbt.edp.rate = DP_LINK_BW_1_62;
However the DP_LINK_BW_* stuff are the values to be written to DPCD. So
different things end up in panel->vbt.edp.rate depending on VBT
version. It's a mess. Should probably have the rate there and throw out
the DP_LINK_BW_* macros.
Otherwise, the logic seems fine.
BR,
Jani.
> + break;
> + case EDP_RATE_2_7:
> + panel->vbt.edp.rate = DP_LINK_BW_2_7;
> + break;
> + case EDP_RATE_5_4:
> + panel->vbt.edp.rate = DP_LINK_BW_5_4;
> + break;
> + default:
> + drm_dbg_kms(&i915->drm,
> + "VBT has unknown eDP link rate value %u\n",
> + edp_link_params->rate);
> + break;
> + }
> }
>
> switch (edp_link_params->lanes) {
> diff --git a/drivers/gpu/drm/i915/display/intel_vbt_defs.h b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> index 14f1e1cc92c5..58aee0a040cf 100644
> --- a/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> +++ b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> @@ -638,6 +638,7 @@ struct bdb_sdvo_panel_dtds {
> #define EDP_30BPP 2
> #define EDP_RATE_1_62 0
> #define EDP_RATE_2_7 1
> +#define EDP_RATE_5_4 2
> #define EDP_LANE_1 0
> #define EDP_LANE_2 1
> #define EDP_LANE_4 3
--
Jani Nikula, Intel Open Source Graphics Center
