[PATCH v4 3/3] dtc: Add support for variable sized elements
Anton Staaf
robotboy at chromium.org
Wed Sep 28 04:11:38 EST 2011
Elements of size 8, 16, 32, and 64 bits are supported. The new
/bits/ syntax was selected so as to not pollute the reserved
keyword space with uint8/uint16/... type names.
With this patch the following property assignment:
property = /bits/ 16 <0x1234 0x5678 0x0 0xffff>;
is equivalent to:
property = <0x12345678 0x0000ffff>;
It is now also possible to directly specify a 64 bit literal in a
cell list, also known as an array using:
property = /bits/ 64 <0xdeadbeef00000000>;
It is an error to attempt to store a literal into an element that is
too small to hold the literal, and the compiler will generate an
error when it detects this. For instance:
property = /bits/ 8 <256>;
Will fail to compile. It is also an error to attempt to place a
reference in a non 32-bit element.
The documentation has been changed to reflect that the cell list
is now an array of elements that can be of sizes other than the
default 32-bit cell size.
The sized_cells test tests the creation and access of 8, 16, 32,
and 64-bit sized elements. It also tests that the creation of two
properties, one with 16 bit elements and one with 32 bit elements
result in the same property contents.
Signed-off-by: Anton Staaf <robotboy at chromium.org>
Cc: Jon Loeliger <jdl at jdl.com>
Cc: David Gibson <david at gibson.dropbear.id.au>
Cc: Grant Likely <grant.likely at secretlab.ca>
---
Documentation/dts-format.txt | 34 +++++++++++-----
dtc-lexer.l | 6 +++
dtc-parser.y | 70 ++++++++++++++++++++++++-----------
tests/.gitignore | 1 +
tests/Makefile.tests | 1 +
tests/run_tests.sh | 3 +
tests/sized_cells.c | 84 ++++++++++++++++++++++++++++++++++++++++++
tests/sized_cells.dts | 11 +++++
8 files changed, 177 insertions(+), 33 deletions(-)
create mode 100644 tests/sized_cells.c
create mode 100644 tests/sized_cells.dts
diff --git a/Documentation/dts-format.txt b/Documentation/dts-format.txt
index 555bd89..8aaa27d 100644
--- a/Documentation/dts-format.txt
+++ b/Documentation/dts-format.txt
@@ -29,18 +29,28 @@ except for properties with empty (zero length) value which have the
form:
[label:] property-name;
-Property values may be defined as an array of 32-bit integer cells, as
-NUL-terminated strings, as bytestrings or a combination of these.
+Property values may be defined as an array of 8, 16, 32, or 64-bit integer
+elements, as NUL-terminated strings, as bytestrings or a combination of these.
-* Arrays of cells are represented by angle brackets surrounding a
- space separated list of C-style integers or character literals.
+* Arrays are represented by angle brackets surrounding a space separated list
+ of C-style integers or character literals. Array elements default to 32-bits
+ in size. An array of 32-bit elements is also known as a cell list or a list
+ of cells. A cell being an unsigned 32-bit integer.
e.g. interrupts = <17 0xc>;
-* A 64-bit value is represented with two 32-bit cells.
+* A 64-bit value can be represented with two 32-bit elements.
e.g. clock-frequency = <0x00000001 0x00000000>;
+* The storage size of an element can be changed using the /bits/ prefix. The
+ /bits/ prefix allows for the creation of 8, 16, 32, and 64-bit elements.
+ The resulting array will not be padded to a multiple of the default 32-bit
+ element size.
+
+ e.g. interrupts = /bits/ 8 <17 0xc>;
+ e.g. clock-frequency = /bits/ 64 <0x0000000100000000>;
+
* A NUL-terminated string value is represented using double quotes
(the property value is considered to include the terminating NUL
character).
@@ -60,19 +70,20 @@ NUL-terminated strings, as bytestrings or a combination of these.
e.g. compatible = "ns16550", "ns8250";
example = <0xf00f0000 19>, "a strange property format";
-* In a cell array a reference to another node will be expanded to that
- node's phandle. References may by '&' followed by a node's label:
+* In an array a reference to another node will be expanded to that node's
+ phandle. References may by '&' followed by a node's label:
e.g. interrupt-parent = < &mpic >;
or they may be '&' followed by a node's full path in braces:
e.g. interrupt-parent = < &{/soc/interrupt-controller at 40000} >;
+ References are only permitted in arrays that have an element size of
+ 32-bits.
-* Outside a cell array, a reference to another node will be expanded
- to that node's full path.
+* Outside an array, a reference to another node will be expanded to that
+ node's full path.
e.g. ethernet0 = &EMAC0;
* Labels may also appear before or after any component of a property
- value, or between cells of a cell array, or between bytes of a
- bytestring.
+ value, or between elements of an array, or between bytes of a bytestring.
e.g. reg = reglabel: <0 sizelabel: 0x1000000>;
e.g. prop = [ab cd ef byte4: 00 ff fe];
e.g. str = start: "string value" end: ;
@@ -109,3 +120,4 @@ Version 1 DTS files have the overall layout:
-- David Gibson <david at gibson.dropbear.id.au>
-- Yoder Stuart <stuart.yoder at freescale.com>
+ -- Anton Staaf <robotboy at chromium.org>
diff --git a/dtc-lexer.l b/dtc-lexer.l
index 494e342..73d190c 100644
--- a/dtc-lexer.l
+++ b/dtc-lexer.l
@@ -97,6 +97,12 @@ static int pop_input_file(void);
return DT_MEMRESERVE;
}
+<*>"/bits/" {
+ DPRINT("Keyword: /bits/\n");
+ BEGIN_DEFAULT();
+ return DT_BITS;
+ }
+
<*>{LABEL}: {
DPRINT("Label: %s\n", yytext);
yylval.labelref = xstrdup(yytext);
diff --git a/dtc-parser.y b/dtc-parser.y
index bc05a24..f89f928 100644
--- a/dtc-parser.y
+++ b/dtc-parser.y
@@ -45,8 +45,12 @@ static unsigned char eval_char_literal(const char *s);
uint8_t byte;
struct data data;
+ struct {
+ struct data data;
+ int bits;
+ } array;
+
uint64_t addr;
- cell_t cell;
struct property *prop;
struct property *proplist;
struct node *node;
@@ -56,6 +60,7 @@ static unsigned char eval_char_literal(const char *s);
%token DT_V1
%token DT_MEMRESERVE
+%token DT_BITS
%token <propnodename> DT_PROPNODENAME
%token <literal> DT_LITERAL
%token <literal> DT_CHAR_LITERAL
@@ -71,8 +76,7 @@ static unsigned char eval_char_literal(const char *s);
%type <re> memreserve
%type <re> memreserves
%type <addr> addr
-%type <data> celllist
-%type <cell> cellval
+%type <array> arrayprefix
%type <data> bytestring
%type <prop> propdef
%type <proplist> proplist
@@ -182,9 +186,9 @@ propdata:
{
$$ = data_merge($1, $2);
}
- | propdataprefix '<' celllist '>'
+ | propdataprefix arrayprefix '>'
{
- $$ = data_merge($1, $3);
+ $$ = data_merge($1, $2.data);
}
| propdataprefix '[' bytestring ']'
{
@@ -242,34 +246,56 @@ propdataprefix:
}
;
-celllist:
- /* empty */
+arrayprefix:
+ DT_BITS DT_LITERAL '<'
{
- $$ = empty_data;
+ $$.data = empty_data;
+ $$.bits = eval_literal($2, 0, 7);
+
+ if (($$.bits != 8) &&
+ ($$.bits != 16) &&
+ ($$.bits != 32) &&
+ ($$.bits != 64))
+ {
+ print_error("Only 8, 16, 32 and 64-bit elements"
+ " are currently supported");
+ $$.bits = 32;
+ }
}
- | celllist cellval
+ | '<'
{
- $$ = data_append_cell($1, $2);
+ $$.data = empty_data;
+ $$.bits = 32;
}
- | celllist DT_REF
+ | arrayprefix DT_LITERAL
{
- $$ = data_append_cell(data_add_marker($1, REF_PHANDLE,
- $2), -1);
+ uint64_t val = eval_literal($2, 0, $1.bits);
+
+ $$.data = data_append_integer($1.data, val, $1.bits);
}
- | celllist DT_LABEL
+ | arrayprefix DT_CHAR_LITERAL
{
- $$ = data_add_marker($1, LABEL, $2);
- }
- ;
+ uint64_t val = eval_char_literal($2);
-cellval:
- DT_LITERAL
+ $$.data = data_append_integer($1.data, val, $1.bits);
+ }
+ | arrayprefix DT_REF
{
- $$ = eval_literal($1, 0, 32);
+ uint64_t val = ~0ULL >> (64 - $1.bits);
+
+ if ($1.bits == 32)
+ $1.data = data_add_marker($1.data,
+ REF_PHANDLE,
+ $2);
+ else
+ print_error("References are only allowed in "
+ "arrays with 32-bit elements.");
+
+ $$.data = data_append_integer($1.data, val, $1.bits);
}
- | DT_CHAR_LITERAL
+ | arrayprefix DT_LABEL
{
- $$ = eval_char_literal($1);
+ $$.data = data_add_marker($1.data, LABEL, $2);
}
;
diff --git a/tests/.gitignore b/tests/.gitignore
index a3e9bd1..9e062c3 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -40,6 +40,7 @@
/set_name
/setprop
/setprop_inplace
+/sized_cells
/string_escapes
/subnode_offset
/supernode_atdepth_offset
diff --git a/tests/Makefile.tests b/tests/Makefile.tests
index cae8390..215a8c5 100644
--- a/tests/Makefile.tests
+++ b/tests/Makefile.tests
@@ -6,6 +6,7 @@ LIB_TESTS_L = get_mem_rsv \
node_check_compatible node_offset_by_compatible \
get_alias \
char_literal \
+ sized_cells \
notfound \
setprop_inplace nop_property nop_node \
sw_tree1 \
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index e2c3046..da6f970 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -209,6 +209,9 @@ dtc_tests () {
run_dtc_test -I dts -O dtb -o dtc_char_literal.test.dtb char_literal.dts
run_test char_literal dtc_char_literal.test.dtb
+ run_dtc_test -I dts -O dtb -o dtc_sized_cells.test.dtb sized_cells.dts
+ run_test sized_cells dtc_sized_cells.test.dtb
+
run_dtc_test -I dts -O dtb -o dtc_extra-terminating-null.test.dtb extra-terminating-null.dts
run_test extra-terminating-null dtc_extra-terminating-null.test.dtb
diff --git a/tests/sized_cells.c b/tests/sized_cells.c
new file mode 100644
index 0000000..847ec96
--- /dev/null
+++ b/tests/sized_cells.c
@@ -0,0 +1,84 @@
+/*
+ * libfdt - Flat Device Tree manipulation
+ * Testcase for variable sized cells in dtc
+ * Copyright (C) 2006 David Gibson, IBM Corporation.
+ * Copyright (C) 2011 The Chromium Authors. All rights reserved.
+ *
+ * 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"
+
+static void check_compare_properties(void *fdt,
+ char const *name_one,
+ char const *name_two)
+{
+ const void *propval;
+ int proplen;
+
+ propval = fdt_getprop(fdt, 0, name_one, &proplen);
+
+ if (!propval)
+ FAIL("fdt_getprop(\"%s\"): %s",
+ name_one,
+ fdt_strerror(proplen));
+
+ check_getprop(fdt, 0, name_two, proplen, propval);
+}
+
+int main(int argc, char *argv[])
+{
+ void *fdt;
+ uint8_t expected_8[6] = {TEST_CHAR1,
+ TEST_CHAR2,
+ TEST_CHAR3,
+ TEST_CHAR4,
+ TEST_CHAR5,
+ TEST_VALUE_1 >> 24};
+ uint16_t expected_16[6];
+ uint32_t expected_32[6];
+ uint64_t expected_64[6];
+ int i;
+
+ for (i = 0; i < 5; ++i) {
+ expected_16[i] = cpu_to_fdt16(expected_8[i]);
+ expected_32[i] = cpu_to_fdt32(expected_8[i]);
+ expected_64[i] = cpu_to_fdt64(expected_8[i]);
+ }
+
+ expected_16[5] = cpu_to_fdt16(TEST_VALUE_1 >> 16);
+ expected_32[5] = cpu_to_fdt32(TEST_VALUE_1);
+ expected_64[5] = cpu_to_fdt64(TEST_ADDR_1);
+
+ test_init(argc, argv);
+ fdt = load_blob_arg(argc, argv);
+
+ check_getprop(fdt, 0, "cells-8b", sizeof(expected_8), expected_8);
+ check_getprop(fdt, 0, "cells-16b", sizeof(expected_16), expected_16);
+ check_getprop(fdt, 0, "cells-32b", sizeof(expected_32), expected_32);
+ check_getprop(fdt, 0, "cells-64b", sizeof(expected_64), expected_64);
+
+ check_compare_properties(fdt, "cells-one-16b", "cells-one-32b");
+
+ PASS();
+}
diff --git a/tests/sized_cells.dts b/tests/sized_cells.dts
new file mode 100644
index 0000000..efea9f5
--- /dev/null
+++ b/tests/sized_cells.dts
@@ -0,0 +1,11 @@
+/dts-v1/;
+
+/ {
+ cells-8b = /bits/ 8 <'\r' 'b' '\0' '\'' '\xff' 0xde>;
+ cells-16b = /bits/ 16 <'\r' 'b' '\0' '\'' '\xff' 0xdead>;
+ cells-32b = /bits/ 32 <'\r' 'b' '\0' '\'' '\xff' 0xdeadbeef>;
+ cells-64b = /bits/ 64 <'\r' 'b' '\0' '\'' '\xff' 0xdeadbeef00000000>;
+
+ cells-one-16b = /bits/ 16 <0x1234 0x5678 0x0 0xffff>;
+ cells-one-32b = <0x12345678 0x0000ffff>;
+};
--
1.7.3.1
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