Allow appending values to a property instead of overriding the previous
values of property.
Currently, we have /delete-node/ and /delete-property/, but lack
/append-property/. Hence we end up having to repeat all existing values
when appending to a property (e.g. see [1] appending to clocks from
[2]).
This functionality is also important for creating a device tree based
implementation to support different types of addon-boards such as
mikroBUS, Grove [3], etc.
The annotate feature works similar to how it works for nodes. Here is a
small example:
base.dtsi
```
/dts-v1/;
/ {
prop = "0";
propa = <0>;
};
```
app1.dtsi
```
/dts-v1/;
/include/ "base.dtsi"
/ {
/append-property/ prop = "1";
};
```
app2.dts
```
/dts-v1/;
/include/ "app1.dtsi"
/ {
/append-property/ prop = "2";
/append-property/ propa = <2>;
};
```
Output:
```
❯ ../dtc -T -T -o temp.dts app2.dts
❯ cat temp.dts
/dts-v1/;
/ { /* base.dtsi:3:3-7:3, app1.dtsi:5:3-7:3, app2.dts:5:3-8:3 */
prop = "0", "1", "2"; /* base.dtsi:4:2-4:13, app1.dtsi:6:2-6:31, app2.dts:6:2-6:31 */
propa = <0x00>, <0x02>; /* base.dtsi:6:3-6:15, app2.dts:7:2-7:32 */
}; /* base.dtsi:3:3-7:3, app1.dtsi:5:3-7:3, app2.dts:5:3-8:3 */
```
[3] https://lore.kernel.org/linux-arm-kernel/20240702164403.29067-1-afd@xxxxxx/
[2] https://elixir.bootlin.com/linux/latest/source/arch/arm64/boot/dts/renesas/r8a77951-salvator-xs.dts#L39
[1] https://elixir.bootlin.com/linux/latest/source/arch/arm64/boot/dts/renesas/r8a77951.dtsi#L3334
Reviewed-by: Simon Glass <sjg@xxxxxxxxxxxx>
Signed-off-by: Ayush Singh <ayush@xxxxxxxxxxxxxxx>
---
dtc-lexer.l | 7 +++++++
dtc-parser.y | 6 ++++++
dtc.h | 5 +++++
livetree.c | 36 +++++++++++++++++++++++++++++-------
4 files changed, 47 insertions(+), 7 deletions(-)
diff --git a/dtc-lexer.l b/dtc-lexer.l
index de60a70b6bdbcb5ae4336ea4171ad6f645e91b36..5da4ca5bbacbababa43d00199d5bb3bc15c8ff6a 100644
--- a/dtc-lexer.l
+++ b/dtc-lexer.l
@@ -137,6 +137,13 @@ static void PRINTF(1, 2) lexical_error(const char *fmt, ...);
return DT_DEL_NODE;
}
+<*>"/append-property/" {
+ DPRINT("Keyword: /append-property/\n");
+ DPRINT("<PROPNODENAME>\n");
+ BEGIN(PROPNODENAME);
+ return DT_APP_PROP;
+ }
+
<*>"/omit-if-no-ref/" {
DPRINT("Keyword: /omit-if-no-ref/\n");
DPRINT("<PROPNODENAME>\n");
diff --git a/dtc-parser.y b/dtc-parser.y
index 4d5eece526243460203157464e3cd75f781e50e7..94ce405ab289ca82680a62bfe71e590f7b2e5e8e 100644
--- a/dtc-parser.y
+++ b/dtc-parser.y
@@ -58,6 +58,7 @@ static bool is_ref_relative(const char *ref)
%token DT_BITS
%token DT_DEL_PROP
%token DT_DEL_NODE
+%token DT_APP_PROP
%token DT_OMIT_NO_REF
%token <propnodename> DT_PROPNODENAME
%token <integer> DT_LITERAL
@@ -296,6 +297,11 @@ propdef:
$$ = build_property_delete($2);
free($2);
}
+ | DT_APP_PROP DT_PROPNODENAME '=' propdata ';'
+ {
+ $$ = build_property_append($2, $4, &@$);
+ free($2);
+ }
| DT_LABEL propdef
{
add_label(&$2->labels, $1);
diff --git a/dtc.h b/dtc.h
index 4c4aaca1fc417c9d93e904e64b2c40216ee1b093..3c9ba5aa92e90dd50995596b753e246d4fa52b24 100644
--- a/dtc.h
+++ b/dtc.h
@@ -205,6 +205,9 @@ struct bus_type {
struct property {
bool deleted;
+ /* Flag to indicate if the property value should be appended instead
+ * of being overwritten */
+ bool append;
char *name;
struct data val;
@@ -263,6 +266,8 @@ void delete_labels(struct label **labels);
struct property *build_property(const char *name, struct data val,
struct srcpos *srcpos);
struct property *build_property_delete(const char *name);
+struct property *build_property_append(const char *name, struct data val,
+ struct srcpos *srcpos);
struct property *chain_property(struct property *first, struct property *list);
struct property *reverse_properties(struct property *first);
diff --git a/livetree.c b/livetree.c
index 49f723002f855764452b30b5a979b6096730a33b..04f5014ab227f2458b8a93fcc6c8cb3a1388fd0d 100644
--- a/livetree.c
+++ b/livetree.c
@@ -62,6 +62,20 @@ struct property *build_property_delete(const char *name)
return new;
}
+struct property *build_property_append(const char *name, struct data val,
+ struct srcpos *srcpos)
+{
+ struct property *new = xmalloc(sizeof(*new));
+
+ memset(new, 0, sizeof(*new));
+ new->name = xstrdup(name);
+ new->append = true;
+ new->val = val;
+ new->srcpos = srcpos_copy(srcpos);
+
+ return new;
+}
+
struct property *chain_property(struct property *first, struct property *list)
{
assert(first->next == NULL);
@@ -151,8 +165,8 @@ struct node *merge_nodes(struct node *old_node, struct node *new_node)
for_each_label_withdel(new_node->labels, l)
add_label(&old_node->labels, l->label);
- /* Move properties from the new node to the old node. If there
- * is a collision, replace the old value with the new */
+ /* Move properties from the new node to the old node. If there
+ * is a collision, replace/append the old value with the new */
while (new_node->proplist) {
/* Pop the property off the list */
new_prop = new_node->proplist;
@@ -165,17 +179,25 @@ struct node *merge_nodes(struct node *old_node, struct node *new_node)
continue;
}
- /* Look for a collision, set new value if there is */
+ /* Look for a collision, set new value/append if there is */
for_each_property_withdel(old_node, old_prop) {
if (streq(old_prop->name, new_prop->name)) {
/* Add new labels to old property */
for_each_label_withdel(new_prop->labels, l)
add_label(&old_prop->labels, l->label);
- old_prop->val = new_prop->val;
- old_prop->deleted = 0;
- free(old_prop->srcpos);
- old_prop->srcpos = new_prop->srcpos;
+ if (new_prop->append) {
+ old_prop->val = data_merge(old_prop->val, new_prop->val);
+ old_prop->srcpos = srcpos_extend(old_prop->srcpos, new_prop->srcpos);
+ }
+ else {
+ old_prop->val = new_prop->val;
+ free(old_prop->srcpos);
+ old_prop->srcpos = new_prop->srcpos;
+ }
+
+ old_prop->deleted = false;
+ old_prop->append = false;
free(new_prop);
new_prop = NULL;
break;
--
2.47.0
