selftests: mlxsw: Test offloadability of root TBF

TBF can be used as a root qdisc, with the usual ETS/RED/TBF hierarchy below
it. This use should now be offloaded. Add a test that verifies that it is.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

tools/testing/selftests/drivers/net/mlxsw/sch_offload.sh

@@ -6,7 +6,9 @@
 
 ALL_TESTS="
 	test_root
+	test_port_tbf
 	test_etsprio
+	test_etsprio_port_tbf
 "
 NUM_NETIFS=1
 lib_dir=$(dirname $0)/../../../net/forwarding
@@ -221,6 +223,12 @@ test_root()
 	do_test_combinations 1 0
 }
 
+test_port_tbf()
+{
+	with_tbf 1: root \
+		do_test_combinations 8 1
+}
+
 do_test_etsprio()
 {
 	local parent=$1; shift
@@ -264,6 +272,12 @@ test_etsprio()
 	do_test_etsprio root ""
 }
 
+test_etsprio_port_tbf()
+{
+	with_tbf 1: root \
+		do_test_etsprio "parent 1:1" "-TBF"
+}
+
 cleanup()
 {
 	tc qdisc del dev $h1 root &>/dev/null