[Intel-gfx] [PATCH 2/2] drm/i915/edp: Use max link rate and lane count if eDP EDID quirk

[Clinton Taylor]

On 4/2/19 2:52 PM, Manasi Navare wrote:
> Some eDP 1.4 panels cannot use the optimized fast and narrow pipe
> config approach, but they need to use th maximum supported lane count
> for the link training to succeed.
> There is a DRM EDID quirk for such panels that gets set after reading
> their corresponding EDID.
> So if it is set, this patch forces the max lane count in compute_config()
> hook to use max lane count for link training.
>
> Cc: Clint Taylor <Clinton.A.Taylor at intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Tested-by: Albert Astals Cid <aacid at kde.org>
> Tested-by: Emanuele Panigati <ilpanich at gmail.com>
> Tested-by: Ralgor <ralgorfdb at compuspex.org>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109959
> Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
> ---
>   drivers/gpu/drm/i915/intel_dp.c  | 5 ++++-
>   drivers/gpu/drm/i915/intel_drv.h | 3 +++
>   2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 72c49070ed14..421db00f5792 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -2028,7 +2028,8 @@ intel_dp_compute_link_config(struct intel_encoder *encoder,
>   	limits.min_bpp = 6 * 3;
>   	limits.max_bpp = intel_dp_compute_bpp(intel_dp, pipe_config);
>   
> -	if (intel_dp_is_edp(intel_dp) && intel_dp->edp_dpcd[0] < DP_EDP_14) {
> +	if (intel_dp->edp_force_max_lane_count || (intel_dp_is_edp(intel_dp) &&
> +						   intel_dp->edp_dpcd[0] < DP_EDP_14)) {
>   		/*
>   		 * Use the maximum clock and number of lanes the eDP panel
>   		 * advertizes being capable of. The eDP 1.3 and earlier panels
> @@ -7101,6 +7102,8 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
>   	edid = drm_get_edid(connector, &intel_dp->aux.ddc);
>   	if (edid) {
>   		if (drm_add_edid_modes(connector, edid)) {
> +			if (connector->display_info.force_max_lane_count)
> +				intel_dp->edp_force_max_lane_count = true;
>   			drm_connector_update_edid_property(connector,
>   								edid);
>   		} else {
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index f8c7b291fdc3..c67c3c518714 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1327,6 +1327,9 @@ struct intel_dp {
>   
>   	/* Display stream compression testing */
>   	bool force_dsc_en;
> +
> +	/* eDP 1.4 EDID quirk to use max lane count */
> +	bool edp_force_max_lane_count;
>   };
>   
>   enum lspcon_vendor {

Reviewed-by: Clint Taylor <Clinton.A.Taylor at intel.com>

-Clint