drm/nouveau/nvif: helper to match against supported class list

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

drivers/gpu/drm/nouveau/include/nvif/object.h

@@ -66,6 +66,35 @@ void nvif_object_unmap(struct nvif_object *);
 
 #define nvif_mthd(a,b,c,d) nvif_object_mthd((a), (b), (c), (d))
 
+struct nvif_mclass {
+	s32 oclass;
+	int version;
+};
+
+#define nvif_mclass(o,m) ({                                                    \
+	struct nvif_object *object = (o);                                      \
+	struct nvif_sclass *sclass;                                            \
+	const typeof(m[0]) *mclass = (m);                                      \
+	int ret = -ENODEV;                                                     \
+	int cnt, i, j;                                                         \
+                                                                               \
+	cnt = nvif_object_sclass_get(object, &sclass);                         \
+	if (cnt >= 0) {                                                        \
+		for (i = 0; ret < 0 && mclass[i].oclass; i++) {                \
+			for (j = 0; j < cnt; j++) {                            \
+				if (mclass[i].oclass  == sclass[j].oclass &&   \
+				    mclass[i].version >= sclass[j].minver &&   \
+				    mclass[i].version <= sclass[j].maxver) {   \
+					ret = i;                               \
+					break;                                 \
+				}                                              \
+			}                                                      \
+		}                                                              \
+		nvif_object_sclass_put(&sclass);                               \
+	}                                                                      \
+	ret;                                                                   \
+})
+
 /*XXX*/
 #include <core/object.h>
 #define nvxx_object(a) ({                                                      \