test: Update tests to use the skip feature

Some tests currently return 0 when they want to be skipped. Update them to
return -EAGAIN instead, so they are counted as skipped.

A few tests are in two parts, with the latter part being skipped in
certain situations. Split these into two and use the correct condition for
the second part.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/test/boot/bootflow.c b/test/boot/bootflow.c
index 1e8ea75..e1e0708 100644
--- a/test/boot/bootflow.c
+++ b/test/boot/bootflow.c
@@ -330,7 +330,7 @@
 	struct udevice *dev;
 
 	if (!IS_ENABLED(CONFIG_CMD_BOOTEFI_BOOTMGR))
-		return 0;
+		return -EAGAIN;
 	ut_assertok(uclass_get_device_by_name(UCLASS_BOOTMETH, "efi_mgr",
 					      &dev));
 	sandbox_set_fake_efi_mgr_dev(dev, true);
@@ -395,7 +395,7 @@
 static int bootflow_scan_glob_bootmeth(struct unit_test_state *uts)
 {
 	if (!IS_ENABLED(CONFIG_BOOTMETH_GLOBAL))
-		return 0;
+		return -EAGAIN;
 
 	ut_assertok(bootstd_test_drop_bootdev_order(uts));
 
diff --git a/test/boot/bootmeth.c b/test/boot/bootmeth.c
index f0b5ab9..0098ef3 100644
--- a/test/boot/bootmeth.c
+++ b/test/boot/bootmeth.c
@@ -103,10 +103,17 @@
 	ut_asserteq_str("efi syslinux", env_get("bootmeths"));
 	ut_assert_console_end();
 
-	/* Try with global bootmeths */
-	if (!IS_ENABLED(CONFIG_BOOTMETH_GLOBAL))
-		return 0;
+	return 0;
+}
+BOOTSTD_TEST(bootmeth_cmd_order, UT_TESTF_DM | UT_TESTF_SCAN_FDT);
 
+/* Check 'bootmeth order' command with global bootmeths */
+static int bootmeth_cmd_order_glob(struct unit_test_state *uts)
+{
+	if (!IS_ENABLED(CONFIG_BOOTMETH_GLOBAL))
+		return -EAGAIN;
+
+	console_record_reset_enable();
 	ut_assertok(run_command("bootmeth order \"efi firmware0\"", 0));
 	ut_assert_console_end();
 	ut_assertok(run_command("bootmeth list", 0));
@@ -122,7 +129,7 @@
 
 	return 0;
 }
-BOOTSTD_TEST(bootmeth_cmd_order, UT_TESTF_DM | UT_TESTF_SCAN_FDT);
+BOOTSTD_TEST(bootmeth_cmd_order_glob, UT_TESTF_DM | UT_TESTF_SCAN_FDT);
 
 /* Check 'bootmeths' env var */
 static int bootmeth_env(struct unit_test_state *uts)
diff --git a/test/boot/vbe_fixup.c b/test/boot/vbe_fixup.c
index 1b488e2..7f0f809 100644
--- a/test/boot/vbe_fixup.c
+++ b/test/boot/vbe_fixup.c
@@ -26,7 +26,7 @@
 	 * flat tree, since device tree fix-ups do not yet support live tree.
 	 */
 	if (!working_fdt)
-		return 0;
+		return -EAGAIN;
 
 	tree = oftree_from_fdt(working_fdt);
 	ut_assert(oftree_valid(tree));
diff --git a/test/dm/of_platdata.c b/test/dm/of_platdata.c
index 7af798b..a241c42 100644
--- a/test/dm/of_platdata.c
+++ b/test/dm/of_platdata.c
@@ -150,7 +150,7 @@
 
 	/* Skip this test if there is no platform data */
 	if (!CONFIG_IS_ENABLED(OF_PLATDATA_DRIVER_RT))
-		return 0;
+		return -EAGAIN;
 
 	/* Record the indexes that are found */
 	memset(found, '\0', sizeof(found));
diff --git a/test/dm/ofnode.c b/test/dm/ofnode.c
index 41811ec..8077aff 100644
--- a/test/dm/ofnode.c
+++ b/test/dm/ofnode.c
@@ -753,10 +753,7 @@
 
 static int dm_test_ofnode_root(struct unit_test_state *uts)
 {
-	char fdt[256];
-	oftree tree;
 	ofnode node;
-	int ret;
 
 	/* Check that aliases work on the control FDT */
 	node = ofnode_get_aliases_node("ethernet3");
@@ -765,14 +762,22 @@
 
 	ut_assert(!oftree_valid(oftree_null()));
 
+	return 0;
+}
+DM_TEST(dm_test_ofnode_root, UT_TESTF_SCAN_FDT);
+
+static int dm_test_ofnode_root_mult(struct unit_test_state *uts)
+{
+	char fdt[256];
+	oftree tree;
+	ofnode node;
+
+	/* skip this test if multiple FDTs are not supported */
+	if (!IS_ENABLED(CONFIG_OFNODE_MULTI_TREE))
+		return -EAGAIN;
+
 	ut_assertok(make_ofnode_fdt(uts, fdt, sizeof(fdt), 0));
-	ret = get_oftree(uts, fdt, &tree);
-
-	/* skip the rest of this test if multiple FDTs are not supported */
-	if (ret == -EOVERFLOW)
-		return 0;
-
-	ut_assertok(ret);
+	ut_assertok(get_oftree(uts, fdt, &tree));
 	ut_assert(oftree_valid(tree));
 
 	/* Make sure they don't work on this new tree */
@@ -791,7 +796,7 @@
 
 	return 0;
 }
-DM_TEST(dm_test_ofnode_root, UT_TESTF_SCAN_FDT);
+DM_TEST(dm_test_ofnode_root_mult, UT_TESTF_SCAN_FDT);
 
 static int dm_test_ofnode_livetree_writing(struct unit_test_state *uts)
 {