drm/nv50-nvc0: fix ramht entries for multiple evo channels

Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_ramht.c

@@ -114,7 +114,9 @@ nouveau_ramht_insert(struct nouveau_channel *chan, u32 handle,
 		      (gpuobj->engine << NV40_RAMHT_CONTEXT_ENGINE_SHIFT);
 	} else {
 		if (gpuobj->engine == NVOBJ_ENGINE_DISPLAY) {
-			ctx = (gpuobj->cinst << 10) | chan->id;
+			ctx = (gpuobj->cinst << 10) |
+			      (chan->id << 28) |
+			      chan->id; /* HASH_TAG */
 		} else {
 			ctx = (gpuobj->cinst >> 4) |
 			      ((gpuobj->engine <<