drm/nv50-/disp: allow dumping core channel state at first supervisor intr

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/core/engine/disp/nvd0.c b/drivers/gpu/drm/nouveau/core/engine/disp/nvd0.c
index 8d553dc..0eac17b 100644
--- a/drivers/gpu/drm/nouveau/core/engine/disp/nvd0.c
+++ b/drivers/gpu/drm/nouveau/core/engine/disp/nvd0.c
@@ -1174,6 +1174,7 @@
 {
 	struct nv50_disp_priv *priv =
 		container_of(work, struct nv50_disp_priv, supervisor);
+	struct nv50_disp_impl *impl = (void *)nv_object(priv)->oclass;
 	u32 mask[4];
 	int head;
 
@@ -1184,6 +1185,7 @@
 	}
 
 	if (priv->super & 0x00000001) {
+		nv50_disp_mthd_chan(priv, NV_DBG_DEBUG, 0, impl->mthd.core);
 		for (head = 0; head < priv->head.nr; head++) {
 			if (!(mask[head] & 0x00001000))
 				continue;