sandbox: test: Provide an easy way to use the other FDT

Add a test flag which indicates that the 'other' FDT should be set up
ready for use. Handle this by copying in the FDT, unflattening it for
livetree tests. Free the structures when the tests have run.

We cannot use the other FDT unless we are using live tree or
OFNODE_MULTI_TREE is enabled, since only one tree is supported by the
ofnode interface in that case. Add this condition into
ut_run_test_live_flat() and update the comments.

Signed-off-by: Simon Glass <sjg@chromium.org>

include/test/test.h

@@ -25,6 +25,7 @@
  * @fdt_size: Size of the device-tree copy
  * @other_fdt: Buffer for the other FDT (UT_TESTF_OTHER_FDT)
  * @other_fdt_size: Size of the other FDT (UT_TESTF_OTHER_FDT)
+ * @of_other: Live tree for the other FDT
  * @runs_per_test: Number of times to run each test (typically 1)
  * @expect_str: Temporary string used to hold expected string value
  * @actual_str: Temporary string used to hold actual string value
@@ -43,6 +44,7 @@ struct unit_test_state {
 	uint fdt_size;
 	void *other_fdt;
 	int other_fdt_size;
+	struct device_node *of_other;
 	int runs_per_test;
 	char expect_str[512];
 	char actual_str[512];
@@ -58,6 +60,7 @@ enum {
 	UT_TESTF_CONSOLE_REC	= BIT(5),	/* needs console recording */
 	/* do extra driver model init and uninit */
 	UT_TESTF_DM		= BIT(6),
+	UT_TESTF_OTHER_FDT	= BIT(7),	/* read in other device tree */
 };
 
 /**

test/test-main.c

@@ -9,6 +9,7 @@
 #include <cyclic.h>
 #include <dm.h>
 #include <event.h>
+#include <of_live.h>
 #include <os.h>
 #include <dm/root.h>
 #include <dm/test.h>
@@ -314,6 +315,20 @@ static int test_pre_run(struct unit_test_state *uts, struct unit_test *test)
 	    (test->flags & UT_TESTF_SCAN_FDT))
 		ut_assertok(dm_extended_scan(false));
 
+	if (IS_ENABLED(CONFIG_SANDBOX) && (test->flags & UT_TESTF_OTHER_FDT)) {
+		/* make sure the other FDT is available */
+		ut_assertok(test_load_other_fdt(uts));
+
+		/*
+		 * create a new live tree with it for every test, in case a
+		 * test modifies the tree
+		 */
+		if (of_live_active()) {
+			ut_assertok(unflatten_device_tree(uts->other_fdt,
+							  &uts->of_other));
+		}
+	}
+
 	if (test->flags & UT_TESTF_CONSOLE_REC) {
 		int ret = console_record_reset_enable();
 
@@ -342,6 +357,9 @@ static int test_post_run(struct unit_test_state *uts, struct unit_test *test)
 	ut_assertok(cyclic_uninit());
 	ut_assertok(event_uninit());
 
+	free(uts->of_other);
+	uts->of_other = NULL;
+
 	return 0;
 }
 
@@ -412,6 +430,9 @@ static int ut_run_test_live_flat(struct unit_test_state *uts,
 {
 	int runs;
 
+	if ((test->flags & UT_TESTF_OTHER_FDT) && !IS_ENABLED(CONFIG_SANDBOX))
+		return -EAGAIN;
+
 	/* Run with the live tree if possible */
 	runs = 0;
 	if (CONFIG_IS_ENABLED(OF_LIVE)) {
@@ -423,10 +444,20 @@ static int ut_run_test_live_flat(struct unit_test_state *uts,
 	}
 
 	/*
-	 * Run with the flat tree if we couldn't run it with live tree,
+	 * Run with the flat tree if:
-	 * or it is a core test.
+	 * - it is not marked for live tree only
+	 * - it doesn't require the 'other' FDT when OFNODE_MULTI_TREE_MAX is
+	 *   not enabled (since flat tree can only support a single FDT in that
+	 *   case
+	 * - we couldn't run it with live tree,
+	 * - it is a core test (dm tests except video)
+	 * - the FDT is still valid and has not been updated by an earlier test
+	 *   (for sandbox we handle this by copying the tree, but not for other
+	 *    boards)
 	 */
 	if (!(test->flags & UT_TESTF_LIVE_TREE) &&
+	    (CONFIG_IS_ENABLED(OFNODE_MULTI_TREE) ||
+	     !(test->flags & UT_TESTF_OTHER_FDT)) &&
 	    (!runs || ut_test_run_on_flattree(test)) &&
 	    !(gd->flags & GD_FLG_FDT_CHANGED)) {
 		uts->of_live = false;
@@ -529,8 +560,10 @@ int ut_run_list(const char *category, const char *prefix,
 	/* Best efforts only...ignore errors */
 	if (has_dm_tests)
 		dm_test_restore(uts.of_root);
-	if (IS_ENABLED(CONFIG_SANDBOX))
+	if (IS_ENABLED(CONFIG_SANDBOX)) {
 		os_free(uts.fdt_copy);
+		os_free(uts.other_fdt);
+	}
 
 	if (ret == -ENOENT)
 		printf("Test '%s' not found\n", select_name);