Support ePAPR compliant phandle properties

Currently, the Linux kernel, libfdt and dtc, when using flattened
device trees encode a node's phandle into a property named
"linux,phandle".  The ePAPR specification, however - aiming as it is
to not be a Linux specific spec - requires that phandles be encoded in
a property named simply "phandle".

This patch adds support for this newer approach to dtc and libfdt.
Specifically:

	- fdt_get_phandle() will now return the correct phandle if it
          is supplied in either of these properties

	- fdt_node_offset_by_phandle() will correctly find a node with
          the given phandle encoded in either property.

	- By default, when auto-generating phandles, dtc will encode
          it into both properties for maximum compatibility.  A new -H
          option allows either only old-style or only new-style
          properties to be generated.

	- If phandle properties are explicitly supplied in the dts
	  file, dtc will not auto-generate ones in the alternate format.

	- If both properties are supplied, dtc will check that they
          have the same value.

	- Some existing testcases are updated to use a mix of old and
          new-style phandles, partially testing the changes.

	- A new phandle_format test further tests the libfdt support,
          and the -H option.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 78 insertions, 0 deletions

diff --git a/tests/phandle_format.c b/tests/phandle_format.c
new file mode 100644
index 0000000..7e4d816
--- /dev/null
+++ b/tests/phandle_format.c
@@ -0,0 +1,78 @@
+/*
+ * libfdt - Flat Device Tree manipulation
+ *	Testcase for phandle format options
+ * Copyright (C) 2009 David Gibson, IBM Corporation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include <fdt.h>
+#include <libfdt.h>
+
+#include "tests.h"
+#include "testdata.h"
+
+#define PHANDLE_LEGACY	0x1
+#define PHANDLE_EPAPR	0x2
+#define PHANDLE_BOTH	0x3
+
+int main(int argc, char *argv[])
+{
+	void *fdt;
+	int phandle_format;
+	int n4;
+	uint32_t h4;
+
+	if (argc != 3)
+		CONFIG("Usage: %s <dtb file> <legacy|epapr|both>\n", argv[0]);
+
+	test_init(argc, argv);
+	fdt = load_blob(argv[1]);
+
+	if (streq(argv[2], "legacy"))
+		phandle_format = PHANDLE_LEGACY;
+	else if (streq(argv[2], "epapr"))
+		phandle_format = PHANDLE_EPAPR;
+	else if (streq(argv[2], "both"))
+		phandle_format = PHANDLE_BOTH;
+	else
+		CONFIG("Usage: %s <dtb file> <legacy|epapr|both>\n", argv[0]);
+
+	n4 = fdt_path_offset(fdt, "/node4");
+	if (n4 < 0)
+		FAIL("fdt_path_offset(/node4): %s", fdt_strerror(n4));
+
+	h4 = fdt_get_phandle(fdt, n4);
+	if ((h4 == 0) || (h4 == -1))
+		FAIL("/node4 has bad phandle 0x%x\n", h4);
+
+	if (phandle_format & PHANDLE_LEGACY)
+		check_getprop_cell(fdt, n4, "linux,phandle", h4);
+	else
+		if (fdt_getprop(fdt, n4, "linux,phandle", NULL))
+			FAIL("linux,phandle property present in non-legacy mode");
+
+	if (phandle_format & PHANDLE_EPAPR)
+		check_getprop_cell(fdt, n4, "phandle", h4);
+	else
+		if (fdt_getprop(fdt, n4, "phandle", NULL))
+			FAIL("phandle property present in legacy-only mode");
+
+	PASS();
+}