drm/i915/dp_mst: Disable Panel Replay

[ Upstream commit f2687d3cc9f905505d7b510c50970176115066a2 ]

Disable Panel Replay on MST links until it's properly implemented. For
instance the required VSC SDP is not programmed on MST and FEC is not
enabled if Panel Replay is enabled.

Fixes: 3257e55d3ea7 ("drm/i915/panelreplay: enable/disable panel replay")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15174
Cc: Jouni Högander <jouni.hogander@intel.com>
Cc: Animesh Manna <animesh.manna@intel.com>
Cc: stable@vger.kernel.org # v6.8+
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20251107124141.911895-1-imre.deak@intel.com
(cherry picked from commit e109f644b871df8440c886a69cdce971ed533088)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
[ placed MST check at function start since DPCD read was moved to caller ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 136a0d6ca970724464f6296b4c79270c93f6be2b..34d61e44c6bd9356fe92c5642f06025461987436 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -591,6 +591,10 @@ static void _panel_replay_init_dpcd(struct intel_dp *intel_dp)
 {
        struct intel_display *display = to_intel_display(intel_dp);
 
+       /* TODO: Enable Panel Replay on MST once it's properly implemented. */
+       if (intel_dp->mst_detect == DRM_DP_MST)
+               return;
+
        if (intel_dp_is_edp(intel_dp)) {
                if (!intel_alpm_aux_less_wake_supported(intel_dp)) {
                        drm_dbg_kms(display->drm,