efi_selftest: check installation of the device tree

The unit test checks if a device tree is installed. It requires that the
'compatible' property of the root node exists. If available it prints the
'serial-number' property.

The serial-number property is derived from the environment variable
'serial#'. This can be used to check if the image_setup_libfdt() function
is executed.

A Python test is supplied. It sets a value for serial# and checks that the
selftest shows this as serial-number.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

2 files changed, 189 insertions, 0 deletions

diff --git a/lib/efi_selftest/Makefile b/lib/efi_selftest/Makefile
index c4bdbdf6c0..88c44840d5 100644
--- a/lib/efi_selftest/Makefile
+++ b/lib/efi_selftest/Makefile
@@ -19,6 +19,7 @@ efi_selftest_console.o \
 efi_selftest_devicepath.o \
 efi_selftest_events.o \
 efi_selftest_exitbootservices.o \
+efi_selftest_fdt.o \
 efi_selftest_gop.o \
 efi_selftest_manageprotocols.o \
 efi_selftest_snp.o \
diff --git a/lib/efi_selftest/efi_selftest_fdt.c b/lib/efi_selftest/efi_selftest_fdt.c
new file mode 100644
index 0000000000..24db0dcf7d
--- /dev/null
+++ b/lib/efi_selftest/efi_selftest_fdt.c
@@ -0,0 +1,188 @@
+/*
+ * efi_selftest_pos
+ *
+ * Copyright (c) 2018 Heinrich Schuchardt <xypron.glpk@gmx.de>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ *
+ * Test the EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.
+ *
+ * The following services are tested:
+ * OutputString, TestString, SetAttribute.
+ */
+
+#include <efi_selftest.h>
+#include <libfdt.h>
+
+static struct efi_boot_services *boottime;
+static const char *fdt;
+
+/* This should be sufficent for */
+#define BUFFERSIZE 0x100000
+
+static efi_guid_t fdt_guid = EFI_FDT_GUID;
+
+/*
+ * Convert FDT value to host endianness.
+ *
+ * @val		FDT value
+ * @return	converted value
+ */
+static uint32_t f2h(fdt32_t val)
+{
+	char *buf = (char *)&val;
+	char i;
+
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+	/* Swap the bytes */
+	i = buf[0]; buf[0] = buf[3]; buf[3] = i;
+	i = buf[1]; buf[1] = buf[2]; buf[2] = i;
+#endif
+	return *(uint32_t *)buf;
+}
+
+/*
+ * Return the value of a property of the FDT root node.
+ *
+ * @name	name of the property
+ * @return	value of the property
+ */
+static char *get_property(const u16 *property)
+{
+	struct fdt_header *header = (struct fdt_header *)fdt;
+	const fdt32_t *pos;
+	const char *strings;
+
+	if (!header)
+		return NULL;
+
+	if (f2h(header->magic) != FDT_MAGIC) {
+		printf("Wrong magic\n");
+		return NULL;
+	}
+
+	pos = (fdt32_t *)(fdt + f2h(header->off_dt_struct));
+	strings = fdt + f2h(header->off_dt_strings);
+
+	for (;;) {
+		switch (f2h(pos[0])) {
+		case FDT_BEGIN_NODE: {
+			char *c = (char *)&pos[1];
+			size_t i;
+
+			for (i = 0; c[i]; ++i)
+				;
+			pos = &pos[2 + (i >> 2)];
+			break;
+		}
+		case FDT_PROP: {
+			struct fdt_property *prop = (struct fdt_property *)pos;
+			const char *label = &strings[f2h(prop->nameoff)];
+			efi_status_t ret;
+
+			/* Check if this is the property to be returned */
+			if (!efi_st_strcmp_16_8(property, label)) {
+				char *str;
+				efi_uintn_t len = f2h(prop->len);
+
+				if (!len)
+					return NULL;
+				/*
+				 * The string might not be 0 terminated.
+				 * It is safer to make a copy.
+				 */
+				ret = boottime->allocate_pool(
+					EFI_LOADER_DATA, len + 1,
+					(void **)&str);
+				if (ret != EFI_SUCCESS) {
+					efi_st_printf("AllocatePool failed\n");
+					return NULL;
+				}
+				boottime->copy_mem(str, &pos[3], len);
+				str[len] = 0;
+
+				return str;
+			}
+
+			pos = &pos[3 + ((f2h(prop->len) + 3) >> 2)];
+			break;
+		}
+		case FDT_NOP:
+			pos = &pos[1];
+			break;
+		default:
+			return NULL;
+		}
+	}
+}
+
+/*
+ * Setup unit test.
+ *
+ * @handle:	handle of the loaded image
+ * @systable:	system table
+ * @return:	EFI_ST_SUCCESS for success
+ */
+static int setup(const efi_handle_t img_handle,
+		 const struct efi_system_table *systable)
+{
+	efi_uintn_t i;
+
+	boottime = systable->boottime;
+
+	/* Find configuration tables */
+	for (i = 0; i < systable->nr_tables; ++i) {
+		if (!efi_st_memcmp(&systable->tables[i].guid, &fdt_guid,
+				   sizeof(efi_guid_t)))
+			fdt = systable->tables[i].table;
+	}
+	if (!fdt) {
+		efi_st_error("Missing device tree\n");
+		return EFI_ST_FAILURE;
+	}
+
+	return EFI_ST_SUCCESS;
+}
+
+/*
+ * Execute unit test.
+ *
+ * @return:	EFI_ST_SUCCESS for success
+ */
+static int execute(void)
+{
+	char *str;
+	efi_status_t ret;
+
+	str = get_property(L"compatible");
+	if (str) {
+		efi_st_printf("compatible: %s\n", str);
+		ret = boottime->free_pool(str);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("FreePool failed\n");
+			return EFI_ST_FAILURE;
+		}
+	} else {
+		efi_st_printf("Missing property 'compatible'\n");
+		return EFI_ST_FAILURE;
+	}
+	str = get_property(L"serial-number");
+	if (str) {
+		efi_st_printf("serial-number: %s\n", str);
+		ret = boottime->free_pool(str);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("FreePool failed\n");
+			return EFI_ST_FAILURE;
+		}
+	}
+
+	return EFI_ST_SUCCESS;
+}
+
+EFI_UNIT_TEST(fdt) = {
+	.name = "device tree",
+	.phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
+	.setup = setup,
+	.execute = execute,
+	.on_request = true,
+};