vbe: Add a test for VBE device tree fixups

When a FIT includes some OS requests, U-Boot should process these and add
the requested info to corresponding subnodes of the /chosen node. Add a
pytest for this, which sets up the FIT, runs bootm and then uses a C
unit test to check that everything looks OK.

The test needs to run on sandbox_flattree since we don't support
device tree fixups on sandbox (live tree) yet. So enable BOOTMETH_VBE and
disable bootflow_system(), since EFI is not supported on
sandbox_flattree.

Add a link to the initial documentation.

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

1 files changed, 59 insertions, 0 deletions

diff --git a/test/boot/vbe_fixup.c b/test/boot/vbe_fixup.c
new file mode 100644
index 00000000000..1b488e25ab6
--- /dev/null
+++ b/test/boot/vbe_fixup.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test for VBE device tree fix-ups
+ *
+ * Copyright 2022 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <common.h>
+#include <dm/ofnode.h>
+#include <linux/libfdt.h>
+#include <test/test.h>
+#include <test/ut.h>
+#include "bootstd_common.h"
+
+/* Basic test of reading nvdata and updating a fwupd node in the device tree */
+static int vbe_test_fixup(struct unit_test_state *uts)
+{
+	ofnode chosen, node;
+	const char *data;
+	oftree tree;
+	int size;
+
+	/*
+	 * This test works when called from test_vbe.py and it must use the
+	 * flat tree, since device tree fix-ups do not yet support live tree.
+	 */
+	if (!working_fdt)
+		return 0;
+
+	tree = oftree_from_fdt(working_fdt);
+	ut_assert(oftree_valid(tree));
+
+	chosen = oftree_path(tree, "/chosen");
+	ut_assert(ofnode_valid(chosen));
+
+	/* check the things set up for the FIT in test_vbe.py */
+	node = ofnode_find_subnode(chosen, "random");
+
+	/* ignore if this test is run on its own */
+	if (!ofnode_valid(node))
+		return 0;
+	data = ofnode_read_prop(node, "data", &size);
+	ut_asserteq(0x40, size);
+
+	node = ofnode_find_subnode(chosen, "aslr2");
+	ut_assert(ofnode_valid(node));
+	data = ofnode_read_prop(node, "data", &size);
+	ut_asserteq(4, size);
+
+	node = ofnode_find_subnode(chosen, "efi-runtime");
+	ut_assert(ofnode_valid(node));
+	data = ofnode_read_prop(node, "data", &size);
+	ut_asserteq(4, size);
+
+	return 0;
+}
+BOOTSTD_TEST(vbe_test_fixup,
+	     UT_TESTF_DM | UT_TESTF_SCAN_FDT | UT_TESTF_FLAT_TREE);