From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> This reverts commit 4eaceea3a00f8e936a7f48dcd0c975a57f88930f. Several userspace clients (modesetting ddx and mutter+wayland at least) handle encoder.possible_crtcs incorrectly. What they essentially do is the following: possible_crtcs = ~0; for_each_possible_encoder(connector) possible_crtcs &= encoder->possible_crtcs; Ie. they calculate the intersection of the possible_crtcs for the connector when they really should be calculating the union instead. In our case each MST encoder now has just one unique bit set, and so the intersection is always zero. The end result is that MST connectors can't be lit up because no crtc can be found to drive them. I've submitted a fix for the modesetting ddx [1], and complained on #wayland about mutter, so hopefully the situation will improve in the future. In the meantime we have regression, and so must go back to the old way of misconfiguring possible_crtcs in the kernel. [1] https://gitlab.freedesktop.org/xorg/xserver/merge_requests/277 Cc: Jonas Ådahl <jadahl@xxxxxxxxx> Cc: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx> Cc: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx> Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111507 Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_dp_mst.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c index 6df240a01b8c..37366f81255b 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c @@ -615,7 +615,7 @@ intel_dp_create_fake_mst_encoder(struct intel_digital_port *intel_dig_port, enum intel_encoder->type = INTEL_OUTPUT_DP_MST; intel_encoder->power_domain = intel_dig_port->base.power_domain; intel_encoder->port = intel_dig_port->base.port; - intel_encoder->crtc_mask = BIT(pipe); + intel_encoder->crtc_mask = 0x7; intel_encoder->cloneable = 0; intel_encoder->compute_config = intel_dp_mst_compute_config; -- 2.21.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx