libfdt: overlay: Refactor overlay_fixup_phandle
Refactored overlay_fixup_phandle to optimize efficiency by moving the
phandle lookup logic based on label outside the overlay_fixup_one_phandle call.
This avoids redundant phandle lookups when a single label is associated with multiple modifications.
Signed-off-by: Zheng Guangyuan <1628513611@qq.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
diff --git a/libfdt/fdt_overlay.c b/libfdt/fdt_overlay.c
index f500f2d..e19506f 100644
--- a/libfdt/fdt_overlay.c
+++ b/libfdt/fdt_overlay.c
@@ -315,7 +315,7 @@
* @name: Name of the property holding the phandle reference in the overlay
* @name_len: number of name characters to consider
* @poffset: Offset within the overlay property where the phandle is stored
- * @label: Label of the node referenced by the phandle
+ * @phandle: Phandle referencing the node
*
* overlay_fixup_one_phandle() resolves an overlay phandle pointing to
* a node in the base device tree.
@@ -332,30 +332,14 @@
int symbols_off,
const char *path, uint32_t path_len,
const char *name, uint32_t name_len,
- int poffset, const char *label)
+ int poffset, uint32_t phandle)
{
- const char *symbol_path;
- uint32_t phandle;
fdt32_t phandle_prop;
- int symbol_off, fixup_off;
- int prop_len;
+ int fixup_off;
if (symbols_off < 0)
return symbols_off;
- symbol_path = fdt_getprop(fdt, symbols_off, label,
- &prop_len);
- if (!symbol_path)
- return prop_len;
-
- symbol_off = fdt_path_offset(fdt, symbol_path);
- if (symbol_off < 0)
- return symbol_off;
-
- phandle = fdt_get_phandle(fdt, symbol_off);
- if (!phandle)
- return -FDT_ERR_NOTFOUND;
-
fixup_off = fdt_path_offset_namelen(fdto, path, path_len);
if (fixup_off == -FDT_ERR_NOTFOUND)
return -FDT_ERR_BADOVERLAY;
@@ -394,6 +378,10 @@
const char *value;
const char *label;
int len;
+ const char *symbol_path;
+ int prop_len;
+ int symbol_off;
+ uint32_t phandle;
value = fdt_getprop_by_offset(fdto, property,
&label, &len);
@@ -404,6 +392,18 @@
return len;
}
+ symbol_path = fdt_getprop(fdt, symbols_off, label, &prop_len);
+ if (!symbol_path)
+ return prop_len;
+
+ symbol_off = fdt_path_offset(fdt, symbol_path);
+ if (symbol_off < 0)
+ return symbol_off;
+
+ phandle = fdt_get_phandle(fdt, symbol_off);
+ if (!phandle)
+ return -FDT_ERR_NOTFOUND;
+
do {
const char *path, *name, *fixup_end;
const char *fixup_str = value;
@@ -445,7 +445,7 @@
ret = overlay_fixup_one_phandle(fdt, fdto, symbols_off,
path, path_len, name, name_len,
- poffset, label);
+ poffset, phandle);
if (ret)
return ret;
} while (len > 0);
