+static void tb_test_credit_alloc_without_dp(struct kunit *test)
+{
+ struct tb_switch *host, *dev;
+ struct tb_port *up, *down;
+ struct tb_tunnel *tunnel;
+ struct tb_path *path;
+
+ host = alloc_host_usb4(test);
+ dev = alloc_dev_without_dp(test, host, 0x1, true);
+
+ /*
+ * The device has no DP therefore baMinDPmain = baMinDPaux = 0
+ *
+ * Create PCIe path with buffers less than baMaxPCIe.
+ *
+ * For a device with buffers configurations:
+ * baMaxUSB3 = 109
+ * baMinDPaux = 0
+ * baMinDPmain = 0
+ * baMaxPCIe = 30
+ * baMaxHI = 1
+ * Remaining Buffers = Total - (CP + DP) = 120 - (2 + 0) = 118
+ * PCIe Credits = Max(6, Min(baMaxPCIe, Remaining Buffers - baMaxUSB3)
+ * = Max(6, Min(30, 9) = 9
+ */
+ down = &host->ports[8];
+ up = &dev->ports[9];
+ tunnel = tb_tunnel_alloc_pci(NULL, up, down);
+ KUNIT_ASSERT_TRUE(test, tunnel != NULL);
+ KUNIT_ASSERT_EQ(test, tunnel->npaths, (size_t)2);
+
+ /* PCIe downstream path */
+ path = tunnel->paths[0];
+ KUNIT_ASSERT_EQ(test, path->path_length, 2);
+ KUNIT_EXPECT_EQ(test, path->hops[0].nfc_credits, 0U);
+ KUNIT_EXPECT_EQ(test, path->hops[0].initial_credits, 7U);
+ KUNIT_EXPECT_EQ(test, path->hops[1].nfc_credits, 0U);
+ KUNIT_EXPECT_EQ(test, path->hops[1].initial_credits, 9U);
+
+ /* PCIe upstream path */
+ path = tunnel->paths[1];
+ KUNIT_ASSERT_EQ(test, path->path_length, 2);
+ KUNIT_EXPECT_EQ(test, path->hops[0].nfc_credits, 0U);
+ KUNIT_EXPECT_EQ(test, path->hops[0].initial_credits, 7U);
+ KUNIT_EXPECT_EQ(test, path->hops[1].nfc_credits, 0U);
+ KUNIT_EXPECT_EQ(test, path->hops[1].initial_credits, 64U);
+
+ tb_tunnel_free(tunnel);
+}
+