Support ePAPR compliant phandle properties
David Gibson
david at gibson.dropbear.id.au
Thu Nov 26 15:37:13 EST 2009
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 at gibson.dropbear.id.au>
Index: dtc/libfdt/fdt_ro.c
===================================================================
--- dtc.orig/libfdt/fdt_ro.c 2009-11-26 15:15:55.027849347 +1100
+++ dtc/libfdt/fdt_ro.c 2009-11-26 15:25:59.130814590 +1100
@@ -274,9 +274,14 @@ uint32_t fdt_get_phandle(const void *fdt
const uint32_t *php;
int len;
- php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
- if (!php || (len != sizeof(*php)))
- return 0;
+ /* FIXME: This is a bit sub-optimal, since we potentially scan
+ * over all the properties twice. */
+ php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
+ if (!php || (len != sizeof(*php))) {
+ php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
+ if (!php || (len != sizeof(*php)))
+ return 0;
+ }
return fdt32_to_cpu(*php);
}
@@ -436,11 +441,27 @@ int fdt_node_offset_by_prop_value(const
int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
{
+ int offset;
+
if ((phandle == 0) || (phandle == -1))
return -FDT_ERR_BADPHANDLE;
- phandle = cpu_to_fdt32(phandle);
- return fdt_node_offset_by_prop_value(fdt, -1, "linux,phandle",
- &phandle, sizeof(phandle));
+
+ FDT_CHECK_HEADER(fdt);
+
+ /* FIXME: The algorithm here is pretty horrible: we
+ * potentially scan each property of a node in
+ * fdt_get_phandle(), then if that didn't find what
+ * we want, we scan over them again making our way to the next
+ * node. Still it's the easiest to implement approach;
+ * performance can come later. */
+ for (offset = fdt_next_node(fdt, -1, NULL);
+ offset >= 0;
+ offset = fdt_next_node(fdt, offset, NULL)) {
+ if (fdt_get_phandle(fdt, offset) == phandle)
+ return offset;
+ }
+
+ return offset; /* error from fdt_next_node() */
}
static int _fdt_stringlist_contains(const char *strlist, int listlen,
Index: dtc/checks.c
===================================================================
--- dtc.orig/checks.c 2009-11-26 15:15:55.123815523 +1100
+++ dtc/checks.c 2009-11-26 15:16:16.391814527 +1100
@@ -279,20 +279,19 @@ static void check_property_name_chars(st
PROP_CHECK(property_name_chars, PROPNODECHARS, ERROR);
static void check_explicit_phandles(struct check *c, struct node *root,
- struct node *node)
+ struct node *node, struct property *prop)
{
- struct property *prop;
struct marker *m;
struct node *other;
cell_t phandle;
- prop = get_property(node, "linux,phandle");
- if (! prop)
- return; /* No phandle, that's fine */
+ if (!streq(prop->name, "phandle")
+ && !streq(prop->name, "linux,phandle"))
+ return;
if (prop->val.len != sizeof(cell_t)) {
- FAIL(c, "%s has bad length (%d) linux,phandle property",
- node->fullpath, prop->val.len);
+ FAIL(c, "%s has bad length (%d) %s property",
+ node->fullpath, prop->val.len, prop->name);
return;
}
@@ -302,9 +301,11 @@ static void check_explicit_phandles(stru
if (node != get_node_by_ref(root, m->ref))
/* "Set this node's phandle equal to some
* other node's phandle". That's nonsensical
- * by construction. */
- FAIL(c, "linux,phandle in %s is a reference to another node",
- node->fullpath);
+ * by construction. */ {
+ FAIL(c, "%s in %s is a reference to another node",
+ prop->name, node->fullpath);
+ return;
+ }
/* But setting this node's phandle equal to its own
* phandle is allowed - that means allocate a unique
* phandle for this node, even if it's not otherwise
@@ -314,14 +315,19 @@ static void check_explicit_phandles(stru
}
phandle = propval_cell(prop);
+
if ((phandle == 0) || (phandle == -1)) {
- FAIL(c, "%s has invalid linux,phandle value 0x%x",
- node->fullpath, phandle);
+ FAIL(c, "%s has bad value (0x%x) in %s property",
+ node->fullpath, phandle, prop->name);
return;
}
+ if (node->phandle && (node->phandle != phandle))
+ FAIL(c, "%s has %s property which replaces existing phandle information",
+ node->fullpath, prop->name);
+
other = get_node_by_phandle(root, phandle);
- if (other) {
+ if (other && (other != node)) {
FAIL(c, "%s has duplicated phandle 0x%x (seen before at %s)",
node->fullpath, phandle, other->fullpath);
return;
@@ -329,7 +335,7 @@ static void check_explicit_phandles(stru
node->phandle = phandle;
}
-NODE_CHECK(explicit_phandles, NULL, ERROR);
+PROP_CHECK(explicit_phandles, NULL, ERROR);
static void check_name_properties(struct check *c, struct node *root,
struct node *node)
Index: dtc/tests/references.dts
===================================================================
--- dtc.orig/tests/references.dts 2009-11-26 15:15:55.163855038 +1100
+++ dtc/tests/references.dts 2009-11-26 15:16:16.391814527 +1100
@@ -8,7 +8,7 @@
lref = <&n2>;
};
n2: node2 {
- linux,phandle = <0x1>;
+ phandle = <0x1>;
ref = <&{/node1}>; /* reference after target */
lref = <&n1>;
};
@@ -29,5 +29,6 @@
* so check it actually works */
n5: node5 {
linux,phandle = <&n5>;
+ phandle = <&n5>;
};
};
Index: dtc/tests/test_tree1.dts
===================================================================
--- dtc.orig/tests/test_tree1.dts 2009-11-26 15:15:55.175815428 +1100
+++ dtc/tests/test_tree1.dts 2009-11-26 15:16:16.395816572 +1100
@@ -26,7 +26,7 @@
prop-int = <123456789>;
subsubnode at 0 {
- linux,phandle = <0x2001>;
+ phandle = <0x2001>;
compatible = "subsubnode2", "subsubnode";
prop-int = <0726746425>;
};
Index: dtc/tests/trees.S
===================================================================
--- dtc.orig/tests/trees.S 2009-11-26 15:15:55.295815042 +1100
+++ dtc/tests/trees.S 2009-11-26 15:16:16.395816572 +1100
@@ -103,7 +103,7 @@ test_tree1_struct:
END_NODE
BEGIN_NODE("subnode at 2")
- PROP_INT(test_tree1, phandle, PHANDLE_1)
+ PROP_INT(test_tree1, linux_phandle, PHANDLE_1)
PROP_INT(test_tree1, prop_int, TEST_VALUE_2)
BEGIN_NODE("subsubnode at 0")
@@ -125,7 +125,8 @@ test_tree1_strings:
STRING(test_tree1, compatible, "compatible")
STRING(test_tree1, prop_int, "prop-int")
STRING(test_tree1, prop_str, "prop-str")
- STRING(test_tree1, phandle, "linux,phandle")
+ STRING(test_tree1, linux_phandle, "linux,phandle")
+ STRING(test_tree1, phandle, "phandle")
test_tree1_strings_end:
test_tree1_end:
Index: dtc/tests/include1.dts
===================================================================
--- dtc.orig/tests/include1.dts 2009-11-26 15:15:55.275848258 +1100
+++ dtc/tests/include1.dts 2009-11-26 15:16:16.395816572 +1100
@@ -15,7 +15,7 @@
prop-int = <123456789>;
/include/ "include8.dts"
- linux,phandle = <0x2001>;
+ phandle = <0x2001>;
compatible = "subsubnode2", "subsubnode";
prop-int = <0726746425>;
};
Index: dtc/tests/sw_tree1.c
===================================================================
--- dtc.orig/tests/sw_tree1.c 2009-11-26 15:15:55.147815499 +1100
+++ dtc/tests/sw_tree1.c 2009-11-26 15:16:16.395816572 +1100
@@ -74,7 +74,7 @@ int main(int argc, char *argv[])
CHECK(fdt_property_cell(fdt, "linux,phandle", PHANDLE_1));
CHECK(fdt_property_cell(fdt, "prop-int", TEST_VALUE_2));
CHECK(fdt_begin_node(fdt, "subsubnode at 0"));
- CHECK(fdt_property_cell(fdt, "linux,phandle", PHANDLE_2));
+ CHECK(fdt_property_cell(fdt, "phandle", PHANDLE_2));
CHECK(fdt_property(fdt, "compatible", "subsubnode2\0subsubnode",
23));
CHECK(fdt_property_cell(fdt, "prop-int", TEST_VALUE_2));
Index: dtc/dtc.c
===================================================================
--- dtc.orig/dtc.c 2009-11-26 15:15:55.107848201 +1100
+++ dtc/dtc.c 2009-11-26 15:16:16.395816572 +1100
@@ -30,6 +30,7 @@ int quiet; /* Level of quietness */
int reservenum; /* Number of memory reservation slots */
int minsize; /* Minimum blob size */
int padsize; /* Additional padding to blob */
+int phandle_format = PHANDLE_BOTH; /* Use linux,phandle or phandle properties */
char *join_path(const char *path, const char *name)
{
@@ -106,6 +107,11 @@ static void __attribute__ ((noreturn))
fprintf(stderr, "\t\tForce - try to produce output even if the input tree has errors\n");
fprintf(stderr, "\t-v\n");
fprintf(stderr, "\t\tPrint DTC version and exit\n");
+ fprintf(stderr, "\t-H <phandle format>\n");
+ fprintf(stderr, "\t\tphandle formats are:\n");
+ fprintf(stderr, "\t\t\tlegacy - \"linux,phandle\" properties only\n");
+ fprintf(stderr, "\t\t\tepapr - \"phandle\" properties only\n");
+ fprintf(stderr, "\t\t\tboth - Both \"linux,phandle\" and \"phandle\" properties\n");
exit(3);
}
@@ -127,7 +133,7 @@ int main(int argc, char *argv[])
minsize = 0;
padsize = 0;
- while ((opt = getopt(argc, argv, "hI:O:o:V:R:S:p:fcqb:v")) != EOF) {
+ while ((opt = getopt(argc, argv, "hI:O:o:V:R:S:p:fcqb:vH:")) != EOF) {
switch (opt) {
case 'I':
inform = optarg;
@@ -165,6 +171,18 @@ int main(int argc, char *argv[])
case 'v':
printf("Version: %s\n", DTC_VERSION);
exit(0);
+ case 'H':
+ if (streq(optarg, "legacy"))
+ phandle_format = PHANDLE_LEGACY;
+ else if (streq(optarg, "epapr"))
+ phandle_format = PHANDLE_EPAPR;
+ else if (streq(optarg, "both"))
+ phandle_format = PHANDLE_BOTH;
+ else
+ die("Invalid argument \"%s\" to -H option\n",
+ optarg);
+ break;
+
case 'h':
default:
usage();
Index: dtc/dtc.h
===================================================================
--- dtc.orig/dtc.h 2009-11-26 15:15:55.067814971 +1100
+++ dtc/dtc.h 2009-11-26 15:16:16.395816572 +1100
@@ -52,6 +52,11 @@ extern int quiet; /* Level of quietness
extern int reservenum; /* Number of memory reservation slots */
extern int minsize; /* Minimum blob size */
extern int padsize; /* Additional padding to blob */
+extern int phandle_format; /* Use linux,phandle or phandle properties */
+
+#define PHANDLE_LEGACY 0x1
+#define PHANDLE_EPAPR 0x2
+#define PHANDLE_BOTH 0x3
typedef uint32_t cell_t;
Index: dtc/tests/Makefile.tests
===================================================================
--- dtc.orig/tests/Makefile.tests 2009-11-26 15:15:55.211848011 +1100
+++ dtc/tests/Makefile.tests 2009-11-26 15:16:16.395816572 +1100
@@ -10,7 +10,8 @@ LIB_TESTS_L = get_mem_rsv \
sw_tree1 \
move_and_save mangle-layout nopulate \
open_pack rw_tree1 set_name setprop del_property del_node \
- string_escapes references path-references boot-cpuid incbin \
+ string_escapes references path-references phandle_format \
+ boot-cpuid incbin \
extra-terminating-null \
dtbs_equal_ordered \
add_subnode_with_nops path_offset_aliases
Index: dtc/tests/phandle_format.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ dtc/tests/phandle_format.c 2009-11-26 15:16:16.395816572 +1100
@@ -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();
+}
Index: dtc/tests/run_tests.sh
===================================================================
--- dtc.orig/tests/run_tests.sh 2009-11-26 15:15:55.191814458 +1100
+++ dtc/tests/run_tests.sh 2009-11-26 15:19:32.986814978 +1100
@@ -219,6 +219,12 @@ dtc_tests () {
run_dtc_test -I dts -O dtb -o dtc_path-references.test.dtb path-references.dts
run_test path-references dtc_path-references.test.dtb
+ run_test phandle_format dtc_references.test.dtb both
+ for f in legacy epapr both; do
+ run_dtc_test -I dts -O dtb -H $f -o dtc_references.test.$f.dtb references.dts
+ run_test phandle_format dtc_references.test.$f.dtb $f
+ done
+
run_dtc_test -I dts -O dtb -o dtc_comments.test.dtb comments.dts
run_dtc_test -I dts -O dtb -o dtc_comments-cmp.test.dtb comments-cmp.dts
run_test dtbs_equal_ordered dtc_comments.test.dtb dtc_comments-cmp.test.dtb
Index: dtc/livetree.c
===================================================================
--- dtc.orig/livetree.c 2009-11-26 15:17:20.275849571 +1100
+++ dtc/livetree.c 2009-11-26 15:18:35.722814886 +1100
@@ -297,12 +297,22 @@ cell_t get_node_phandle(struct node *roo
phandle++;
node->phandle = phandle;
- if (!get_property(node, "linux,phandle"))
+
+ if (!get_property(node, "linux,phandle")
+ && (phandle_format & PHANDLE_LEGACY))
add_property(node,
build_property("linux,phandle",
data_append_cell(empty_data, phandle),
NULL));
- /* If the node *does* have a linux,phandle property, we must
+
+ if (!get_property(node, "phandle")
+ && (phandle_format & PHANDLE_EPAPR))
+ add_property(node,
+ build_property("phandle",
+ data_append_cell(empty_data, phandle),
+ NULL));
+
+ /* If the node *does* have a phandle property, we must
* be dealing with a self-referencing phandle, which will be
* fixed up momentarily in the caller */
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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