You may define constants as follows:
/define/ TWO 2;
/define/ FOUR 4;
/define/ OTHER FOUR;
And properties may use these values as follows:
foo = <1 TWO 3 FOUR 5>;
Signed-off-by: Stephen Warren <swar...@nvidia.com>
---
I posted this back in early September. I'd like to ask again that this
feature be merged into dtc; there are many situations where it'd allow
.dts files to be simplified.
My earlier posting was blocked by a lack of consensus on the direction
of macro/expression support in dtc. I haven't seen any move to resolve
this since. Can we please move forward with simple expression support;
it seems to be the most immediately useful aspect of any macro/
expression support. The alternative is to either continue to suffer with
unreadable integer constants, or perhaps pre-process before passing the
.dts file to dtc, thus making any macro support in dtc moot.
dtc-lexer.l | 13 +++++++++
dtc-parser.y | 73 +++++++++++++++++++++++++++++++++++++++++++++++++
tests/Makefile.tests | 3 +-
tests/identifiers.c | 44 +++++++++++++++++++++++++++++
tests/identifiers.dts | 12 ++++++++
tests/run_tests.sh | 4 +++
6 files changed, 148 insertions(+), 1 deletions(-)
create mode 100644 tests/identifiers.c
create mode 100644 tests/identifiers.dts
diff --git a/dtc-lexer.l b/dtc-lexer.l
index e866ea5..60a0677 100644
--- a/dtc-lexer.l
+++ b/dtc-lexer.l
@@ -28,6 +28,7 @@
PROPNODECHAR [a-zA-Z0-9,._+*#?@-]
PATHCHAR ({PROPNODECHAR}|[/])
LABEL [a-zA-Z_][a-zA-Z0-9_]*
+IDENTIFIER [a-zA-Z_][a-zA-Z0-9_]*
STRING \"([^\\"]|\\.)*\"
WS [[:space:]]
COMMENT "/*"([^*]|\*+[^*/])*\*+"/"
@@ -96,6 +97,12 @@ static int pop_input_file(void);
return DT_MEMRESERVE;
}
+<*>"/define/" {
+ DPRINT("Keyword: /define/\n");
+ BEGIN_DEFAULT();
+ return DT_DEFINE;
+ }
+
<*>{LABEL}: {
DPRINT("Label: %s\n", yytext);
yylval.labelref = xstrdup(yytext);
@@ -103,6 +110,12 @@ static int pop_input_file(void);
return DT_LABEL;
}
+<V1>{IDENTIFIER} {
+ DPRINT("identifier: %s\n", yytext);
+ yylval.identifier = xstrdup(yytext);
+ return DT_IDENTIFIER;
+ }
+
<V1>[0-9]+|0[xX][0-9a-fA-F]+ {
yylval.literal = xstrdup(yytext);
DPRINT("Literal: '%s'\n", yylval.literal);
diff --git a/dtc-parser.y b/dtc-parser.y
index 5e84a67..0558c38 100644
--- a/dtc-parser.y
+++ b/dtc-parser.y
@@ -33,6 +33,9 @@ extern void yyerror(char const *s);
extern struct boot_info *the_boot_info;
extern int treesource_error;
+static struct identifier *get_identifier(const char *s);
+static void set_identifier(const char *name, unsigned long long value);
+static unsigned long long eval_identifier(const char *name);
static unsigned long long eval_literal(const char *s, int base, int bits);
%}
@@ -40,6 +43,7 @@ static unsigned long long eval_literal(const char *s, int
base, int bits);
char *propnodename;
char *literal;
char *labelref;
+ char *identifier;
unsigned int cbase;
uint8_t byte;
struct data data;
@@ -55,7 +59,9 @@ static unsigned long long eval_literal(const char *s, int
base, int bits);
%token DT_V1
%token DT_MEMRESERVE
+%token DT_DEFINE
%token <propnodename> DT_PROPNODENAME
+%token <identifier> DT_IDENTIFIER
%token <literal> DT_LITERAL
%token <cbase> DT_BASE
%token <byte> DT_BYTE
@@ -113,6 +119,13 @@ memreserve:
}
;
+define:
+ DT_DEFINE DT_IDENTIFIER cellval ';'
+ {
+ set_identifier($2, $3);
+ }
+ ;
+
addr:
DT_LITERAL
{
@@ -125,6 +138,10 @@ devicetree:
{
$$ = name_node($2, "");
}
+ | define
+ {
+ $$ = name_node(build_node(NULL, NULL), "");
+ }
| devicetree '/' nodedef
{
$$ = merge_nodes($1, $3);
@@ -139,6 +156,10 @@ devicetree:
print_error("label or path, '%s', not found",
$2);
$$ = $1;
}
+ | devicetree define
+ {
+ $$ = $1;
+ }
;
nodedef:
@@ -265,6 +286,10 @@ cellval:
{
$$ = eval_literal($1, 0, 32);
}
+ | DT_IDENTIFIER
+ {
+ $$ = eval_identifier($1);
+ }
;
bytestring:
@@ -327,6 +352,54 @@ void yyerror(char const *s) {
print_error("%s", s);
}
+struct identifier {
+ const char *name;
+ unsigned long long value;
+ struct identifier *next;
+};
+static struct identifier *identifiers;
+
+static struct identifier *get_identifier(const char *name)
+{
+ struct identifier *identifier = identifiers;
+
+ while (identifier != NULL) {
+ if (streq(name, identifier->name))
+ return identifier;
+ identifier = identifier->next;
+ }
+
+ return NULL;
+}
+
+static void set_identifier(const char *name, unsigned long long value)
+{
+ struct identifier *identifier;
+
+ if (get_identifier(name) != NULL) {
+ print_error("redefining %s", name);
+ return;
+ }
+
+ identifier = xmalloc(sizeof(*identifier));
+ identifier->name = name;
+ identifier->value = value;
+ identifier->next = identifiers;
+ identifiers = identifier;
+}
+
+unsigned long long eval_identifier(const char *name)
+{
+ struct identifier *identifier = get_identifier(name);
+
+ if (identifier == NULL) {
+ print_error("identifier %s does not exist", name);
+ return 0;
+ }
+
+ return identifier->value;
+}
+
static unsigned long long eval_literal(const char *s, int base, int bits)
{
unsigned long long val;
diff --git a/tests/Makefile.tests b/tests/Makefile.tests
index c564e72..25d2e3c 100644
--- a/tests/Makefile.tests
+++ b/tests/Makefile.tests
@@ -15,7 +15,8 @@ LIB_TESTS_L = get_mem_rsv \
extra-terminating-null \
dtbs_equal_ordered \
dtb_reverse dtbs_equal_unordered \
- add_subnode_with_nops path_offset_aliases
+ add_subnode_with_nops path_offset_aliases \
+ identifiers
LIB_TESTS = $(LIB_TESTS_L:%=$(TESTS_PREFIX)%)
LIBTREE_TESTS_L = truncated_property
diff --git a/tests/identifiers.c b/tests/identifiers.c
new file mode 100644
index 0000000..a013d00
--- /dev/null
+++ b/tests/identifiers.c
@@ -0,0 +1,44 @@
+/*
+ * libfdt - Flat Device Tree manipulation
+ * Testcase for /define/
+ * Copyright (C) 2011 NVIDIA, Inc.
+ * Derived from code:
+ * Copyright (C) 2006 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"
+
+int main(int argc, char *argv[])
+{
+ void *fdt;
+
+ test_init(argc, argv);
+ fdt = load_blob_arg(argc, argv);
+
+ check_property_cell(fdt, 0, "var1", TEST_VALUE_1);
+ check_property_cell(fdt, 0, "var2", TEST_VALUE_1);
+
+ PASS();
+}
diff --git a/tests/identifiers.dts b/tests/identifiers.dts
new file mode 100644
index 0000000..e8d8e23
--- /dev/null
+++ b/tests/identifiers.dts
@@ -0,0 +1,12 @@
+/dts-v1/;
+
+/define/ VAR1 0xdeadbeef;
+/define/ VAR2 VAR1;
+
+/ {
+ var1 = <VAR1>;
+ var2 = <VAR2>;
+};
+
+/define/ OTHER 0xdeadbeef;
+
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index 72dda32..e0da087 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -343,6 +343,10 @@ dtc_tests () {
run_dtc_test -I dtb -O dts -o stdin_odts_test_tree1.dtb.test.dts - <
test_tree1.dtb
run_wrap_test cmp stdin_odts_test_tree1.dtb.test.dts
odts_test_tree1.dtb.test.dts
+ # Test identifiers
+ run_dtc_test -I dts -O dtb -o identifiers.dtb identifiers.dts
+ run_test identifiers identifiers.dtb
+
# Check for graceful failure in some error conditions
run_sh_test dtc-fatal.sh -I dts -O dtb nosuchfile.dts
run_sh_test dtc-fatal.sh -I dtb -O dtb nosuchfile.dtb
--
1.7.0.4
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