Commit 1ed04202 authored by Imre Deak's avatar Imre Deak
Browse files

drm/i915/dp_mst: Verify the link status always the same way 



The MST link status should be always verified from the same DPCD
registers after link training. Atm, both the legacy (0x202 - 0x205) and
the ESI (0x200C - 0x200F) link status registers are used. Use always the
latter ESI version of link status registers.

v2: Propagate error from intel_dp_read_link_status(). (Jani, Luca)

Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: default avatarLuca Coelho <luciano.coelho@intel.com>
Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260225164618.1261368-3-imre.deak@intel.com
parent c51348f0

drivers/gpu/drm/i915/display/intel_dp.c

+18 −2
Original line number Diff line number Diff line
@@ -5568,6 +5568,23 @@ intel_dp_handle_hdmi_link_status_change(struct intel_dp *intel_dp) 
	}

}



static int

intel_dp_read_link_status(struct intel_dp *intel_dp, u8 link_status[DP_LINK_STATUS_SIZE])

{

	int err;



	memset(link_status, 0, DP_LINK_STATUS_SIZE);



	if (intel_dp_mst_active_streams(intel_dp) > 0)

		err = drm_dp_dpcd_read_data(&intel_dp->aux, DP_LANE0_1_STATUS_ESI,

					    link_status, DP_LINK_STATUS_SIZE - 2);

	else

		err = drm_dp_dpcd_read_phy_link_status(&intel_dp->aux, DP_PHY_DPRX,

						       link_status);



	return err;

}



static bool

intel_dp_needs_link_retrain(struct intel_dp *intel_dp)

{
@@ -5590,8 +5607,7 @@ intel_dp_needs_link_retrain(struct intel_dp *intel_dp) 
	if (intel_dp->link.force_retrain)

		return true;



	if (drm_dp_dpcd_read_phy_link_status(&intel_dp->aux, DP_PHY_DPRX,

					     link_status) < 0)

	if (intel_dp_read_link_status(intel_dp, link_status) < 0)

		return false;



	/*