drm/nouveau/gr/gf100: select a stream master to fixup tfb offset queries

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c b/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c
index c56a886..b2de290 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/gr/gf100.c
@@ -1832,6 +1832,8 @@
 
 	gf100_gr_mmio(gr, gr->func->mmio);
 
+	nvkm_mask(device, TPC_UNIT(0, 0, 0x05c), 0x00000001, 0x00000001);
+
 	memcpy(tpcnr, gr->tpc_nr, sizeof(gr->tpc_nr));
 	for (i = 0, gpc = -1; i < gr->tpc_total; i++) {
 		do {