[PATCH v4 0/3] Variable sized array element support

[PATCH v4 0/3] Variable sized array element support

[Anton Staaf]

This patch set adds, tests, and documents support for variable sized elements in
arrays (known as cell lists when they could only support 32-bit entries).  The
new syntax is:

    property = /bits/ [8|16|32|64] <0x00 .... 0x12>;

So arrays of 8, 16, 32, or 64-bit elements can now be created.  No padding is
done on the resulting array.  So if three 8-bit elements are specified the
resulting property will contain three bytes.

Changes in v2:
- sized_data renamed to celllist
- celllist definition moved to dtc-parser.y
- celllist non-terminal renamed to celllistprefix
- references always appended as -1 masked to the size of the cell
- smaller test values derived from TEST_VALUE_1
- data_append_literal renamed to data_append_integer
- be_ removed from values in data_append_integer
- len renamed to bits in data_append_integer

Changes in v3:
- Renamed size to bits in docs, parser, commit messages, and celllist struct
- Remove die on overflow from data_append_integer
- Rewrite data_append_cell|addr in terms of data_append_integer
- Minor cosmetic change to property names in test case (added 'b' to last two)

Changes in v4:
- Only add phandle reference marker when element size is 32-bits
- Rename non-terminal celllistprefix to arrayprefix
- Rename semantic variable celllist to array
- Update documentation to use array and element instead of cell list and cell

Anton Staaf (3):
  libfdt: Add fdt16_to_cpu utility function
  dtc: Add data_append_integer function
  dtc: Add support for variable sized elements

 Documentation/dts-format.txt |   34 +++++++++++-----
 data.c                       |   39 ++++++++++++++++---
 dtc-lexer.l                  |    6 +++
 dtc-parser.y                 |   70 ++++++++++++++++++++++++-----------
 dtc.h                        |    1 +
 libfdt/libfdt_env.h          |    6 +++
 tests/.gitignore             |    1 +
 tests/Makefile.tests         |    1 +
 tests/run_tests.sh           |    3 +
 tests/sized_cells.c          |   84 ++++++++++++++++++++++++++++++++++++++++++
 tests/sized_cells.dts        |   11 +++++
 11 files changed, 216 insertions(+), 40 deletions(-)
 create mode 100644 tests/sized_cells.c
 create mode 100644 tests/sized_cells.dts

-- 
1.7.3.1

[PATCH v4 1/3] libfdt: Add fdt16_to_cpu utility function

[Anton Staaf]

This utility routine will be used in the variable size cell literal
append code.  It is a straightforward adaptation of the fdt32_to_cpu
function.

Signed-off-by: Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Cc: Jon Loeliger <jdl-CYoMK+44s/E@public.gmane.org>
Cc: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
Cc: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
---
 libfdt/libfdt_env.h |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/libfdt/libfdt_env.h b/libfdt/libfdt_env.h
index 449bf60..da952e7 100644
--- a/libfdt/libfdt_env.h
+++ b/libfdt/libfdt_env.h
@@ -6,6 +6,12 @@
 #include <string.h>
 
 #define _B(n)	((unsigned long long)((uint8_t *)&x)[n])
+static inline uint16_t fdt16_to_cpu(uint16_t x)
+{
+	return (_B(0) << 8) | _B(1);
+}
+#define cpu_to_fdt16(x) fdt16_to_cpu(x)
+
 static inline uint32_t fdt32_to_cpu(uint32_t x)
 {
 	return (_B(0) << 24) | (_B(1) << 16) | (_B(2) << 8) | _B(3);
-- 
1.7.3.1

[PATCH v4 2/3] dtc: Add data_append_integer function

[Anton Staaf]

This function deals with appending integers of various sizes (8, 16
32, and 64 bit currently).  It handles endianess conversions.  If the
integer will not fit in the requested number of bits of storage it
will have it's high bits ignored.

This patch also rewrites data_append_cell and data_append_addr to use
data_append_integer.

Signed-off-by: Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Cc: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
Cc: Jon Loeliger <jdl-CYoMK+44s/E@public.gmane.org>
Cc: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
---
 data.c |   39 ++++++++++++++++++++++++++++++++-------
 dtc.h  |    1 +
 2 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/data.c b/data.c
index b5f3066..4a40c5b 100644
--- a/data.c
+++ b/data.c
@@ -168,11 +168,33 @@ struct data data_merge(struct data d1, struct data d2)
 	return d;
 }
 
-struct data data_append_cell(struct data d, cell_t word)
+struct data data_append_integer(struct data d, uint64_t value, int bits)
 {
-	cell_t beword = cpu_to_fdt32(word);
-
-	return data_append_data(d, &beword, sizeof(beword));
+	uint8_t value_8;
+	uint16_t value_16;
+	uint32_t value_32;
+	uint64_t value_64;
+
+	switch (bits) {
+	case 8:
+		value_8 = value;
+		return data_append_data(d, &value_8, 1);
+
+	case 16:
+		value_16 = cpu_to_fdt16(value);
+		return data_append_data(d, &value_16, 2);
+
+	case 32:
+		value_32 = cpu_to_fdt32(value);
+		return data_append_data(d, &value_32, 4);
+
+	case 64:
+		value_64 = cpu_to_fdt64(value);
+		return data_append_data(d, &value_64, 8);
+
+	default:
+		die("Invalid literal size (%d)\n", bits);
+	}
 }
 
 struct data data_append_re(struct data d, const struct fdt_reserve_entry *re)
@@ -185,11 +207,14 @@ struct data data_append_re(struct data d, const struct fdt_reserve_entry *re)
 	return data_append_data(d, &bere, sizeof(bere));
 }
 
-struct data data_append_addr(struct data d, uint64_t addr)
+struct data data_append_cell(struct data d, cell_t word)
 {
-	uint64_t beaddr = cpu_to_fdt64(addr);
+	return data_append_integer(d, word, sizeof(word) * 8);
+}
 
-	return data_append_data(d, &beaddr, sizeof(beaddr));
+struct data data_append_addr(struct data d, uint64_t addr)
+{
+	return data_append_integer(d, addr, sizeof(addr) * 8);
 }
 
 struct data data_append_byte(struct data d, uint8_t byte)
diff --git a/dtc.h b/dtc.h
index f37c97e..7b4c65b 100644
--- a/dtc.h
+++ b/dtc.h
@@ -109,6 +109,7 @@ struct data data_insert_at_marker(struct data d, struct marker *m,
 				  const void *p, int len);
 struct data data_merge(struct data d1, struct data d2);
 struct data data_append_cell(struct data d, cell_t word);
+struct data data_append_integer(struct data d, uint64_t word, int bits);
 struct data data_append_re(struct data d, const struct fdt_reserve_entry *re);
 struct data data_append_addr(struct data d, uint64_t addr);
 struct data data_append_byte(struct data d, uint8_t byte);
-- 
1.7.3.1

[PATCH v4 3/3] dtc: Add support for variable sized elements

[Anton Staaf]

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-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Cc: Jon Loeliger <jdl-CYoMK+44s/E@public.gmane.org>
Cc: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
Cc: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
---
 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@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-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
 	-- Yoder Stuart <stuart.yoder-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
+	-- Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.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

Re: [PATCH v4 1/3] libfdt: Add fdt16_to_cpu utility function

[David Gibson]

On Tue, Sep 27, 2011 at 11:11:36AM -0700, Anton Staaf wrote:
> This utility routine will be used in the variable size cell literal
> append code.  It is a straightforward adaptation of the fdt32_to_cpu
> function.
> 
> Signed-off-by: Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>

Acked-by: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>

-- 
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

Re: [PATCH v4 2/3] dtc: Add data_append_integer function

[David Gibson]

On Tue, Sep 27, 2011 at 11:11:37AM -0700, Anton Staaf wrote:
> This function deals with appending integers of various sizes (8, 16
> 32, and 64 bit currently).  It handles endianess conversions.  If the
> integer will not fit in the requested number of bits of storage it
> will have it's high bits ignored.
> 
> This patch also rewrites data_append_cell and data_append_addr to use
> data_append_integer.
> 
> Signed-off-by: Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>

Acked-by: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>

-- 
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

Re: [PATCH v4 3/3] dtc: Add support for variable sized elements

[David Gibson]

On Tue, Sep 27, 2011 at 11:11:38AM -0700, Anton Staaf wrote:
> 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-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>

What the hell, I think I've convinced myself that /bits/ is good
enough.

Acked-by: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>

-- 
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

Re: [PATCH v4 3/3] dtc: Add support for variable sized elements

[Anton Staaf]

On Tue, Oct 11, 2011 at 7:44 AM, David Gibson
<david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org> wrote:
> On Tue, Sep 27, 2011 at 11:11:38AM -0700, Anton Staaf wrote:
>> 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-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
>
> What the hell, I think I've convinced myself that /bits/ is good
> enough.

Thanks David, I haven't thought of anything more appropriate either.
I'm looking forward to getting this landed.  :)

-Anton

> Acked-by: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
>
> --
> 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
>

Re: [PATCH v4 3/3] dtc: Add support for variable sized elements

[Jon Loeliger]

> >>
> >> Signed-off-by: Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
> >
> > What the hell, I think I've convinced myself that /bits/ is good
> > enough.
> 
> Thanks David, I haven't thought of anything more appropriate either.
> I'm looking forward to getting this landed.  :)

To facilitate that, could you post current patch set again?

Thanks,
jdl

Re: [PATCH v4 3/3] dtc: Add support for variable sized elements

[Anton Staaf]

On Tue, Oct 11, 2011 at 8:22 AM, Jon Loeliger <jdl-CYoMK+44s/E@public.gmane.org> wrote:
>> >>
>> >> Signed-off-by: Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
>> >
>> > What the hell, I think I've convinced myself that /bits/ is good
>> > enough.
>>
>> Thanks David, I haven't thought of anything more appropriate either.
>> I'm looking forward to getting this landed.  :)
>
> To facilitate that, could you post current patch set again?

Will do, v4 still applies so I'll just move David's Acks to it and repost it.

Thanks,
    Anton

> Thanks,
> jdl
>

[PATCH v4 1/3] libfdt: Add fdt16_to_cpu utility function

[Anton Staaf]

This utility routine will be used in the variable size cell literal
append code.  It is a straightforward adaptation of the fdt32_to_cpu
function.

Signed-off-by: Anton Staaf <robotboy-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Acked-by: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
Cc: Jon Loeliger <jdl-CYoMK+44s/E@public.gmane.org>
Cc: David Gibson <david-xT8FGy+AXnRB3Ne2BGzF6laj5H9X9Tb+@public.gmane.org>
Cc: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>
---
 libfdt/libfdt_env.h |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/libfdt/libfdt_env.h b/libfdt/libfdt_env.h
index 449bf60..da952e7 100644
--- a/libfdt/libfdt_env.h
+++ b/libfdt/libfdt_env.h
@@ -6,6 +6,12 @@
 #include <string.h>
 
 #define _B(n)	((unsigned long long)((uint8_t *)&x)[n])
+static inline uint16_t fdt16_to_cpu(uint16_t x)
+{
+	return (_B(0) << 8) | _B(1);
+}
+#define cpu_to_fdt16(x) fdt16_to_cpu(x)
+
 static inline uint32_t fdt32_to_cpu(uint32_t x)
 {
 	return (_B(0) << 24) | (_B(1) << 16) | (_B(2) << 8) | _B(3);
-- 
1.7.3.1