From b513a18cf1d705bd04efd91c417e79e4938be093 Mon Sep 17 00:00:00 2001
From: Lyude Paul <lyude@redhat.com>
Date: Mon, 28 Jan 2019 16:03:50 -0500
Subject: drm/nouveau: Don't WARN_ON VCPI allocation failures
Git-commit: b513a18cf1d705bd04efd91c417e79e4938be093
Patch-mainline: v5.1-rc1
References: bsc#1113722

This is much louder then we want. VCPI allocation failures are quite
normal, since they will happen if any part of the modesetting process is
interrupted by removing the DP MST topology in question. So just print a
debugging message on VCPI failures instead.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: f479c0ba4a17 ("drm/nouveau/kms/nv50: initial support for DP 1.2 multi-stream")
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/nouveau/dispnv50/disp.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -759,7 +759,8 @@ nv50_msto_enable(struct drm_encoder *enc
 
 	slots = drm_dp_find_vcpi_slots(&mstm->mgr, mstc->pbn);
 	r = drm_dp_mst_allocate_vcpi(&mstm->mgr, mstc->port, mstc->pbn, slots);
-	WARN_ON(!r);
+	if (!r)
+		DRM_DEBUG_KMS("Failed to allocate VCPI\n");
 
 	if (!mstm->links++)
 		nv50_outp_acquire(mstm->outp);