fdt: Add a function to decode a variable-sized u32 array

Sometimes an array can be of variable size up to a maximum. Add a helper function to decode this. Signed-off-by: Simon Glass <sjg@chromium.org>

fdt: Add a function to decode a variable-sized u32 array
Sometimes an array can be of variable size up to a maximum. Add a helper function to decode this. Signed-off-by: Simon Glass <sjg@chromium.org>
Simon Glass
1 parent 768e0f52f2
Showing 2 changed files with 36 additions and 0 deletions Side-by-side Diff
include/fdtdec.h
lib/fdtdec.c
@@ -445,6 +445,22 @@
 		u32 *array, int count);
  
 /**
+ * Look up a property in a node and return its contents in an integer
+ * array of given length. The property must exist but may have less data that
+ * expected (4*count bytes). It may have more, but this will be ignored.
+ *
+ * @param blob		FDT blob
+ * @param node		node to examine
+ * @param prop_name	name of property to find
+ * @param array		array to fill with data
+ * @param count		number of array elements
+ * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
+ *		property is not found
+ */
+int fdtdec_get_int_array_count(const void *blob, int node,
+			       const char *prop_name, u32 *array, int count);
+
+/**
  * Look up a property in a node and return a pointer to its contents as a
  * unsigned int array of given length. The property must have at least enough
  * data for the array ('count' cells). It may have more, but this will be
@@ -485,6 +485,26 @@
 	return err;
 }
  
+int fdtdec_get_int_array_count(const void *blob, int node,
+			       const char *prop_name, u32 *array, int count)
+{
+	const u32 *cell;
+	int len, elems;
+	int i;
+
+	debug("%s: %s\n", __func__, prop_name);
+	cell = fdt_getprop(blob, node, prop_name, &len);
+	if (!cell)
+		return -FDT_ERR_NOTFOUND;
+	elems = len / sizeof(u32);
+	if (count > elems)
+		count = elems;
+	for (i = 0; i < count; i++)
+		array[i] = fdt32_to_cpu(cell[i]);
+
+	return count;
+}
+
 const u32 *fdtdec_locate_array(const void *blob, int node,
 			       const char *prop_name, int count)
 {
...	...	@@ -445,6 +445,22 @@
445	445	u32 *array, int count);
446	446
447	447	/**
	448	+ * Look up a property in a node and return its contents in an integer
	449	+ * array of given length. The property must exist but may have less data that
	450	+ * expected (4*count bytes). It may have more, but this will be ignored.
	451	+ *
	452	+ * @param blob FDT blob
	453	+ * @param node node to examine
	454	+ * @param prop_name name of property to find
	455	+ * @param array array to fill with data
	456	+ * @param count number of array elements
	457	+ * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
	458	+ * property is not found
	459	+ */
	460	+int fdtdec_get_int_array_count(const void *blob, int node,
	461	+ const char prop_name, u32 array, int count);
	462	+
	463	+/**
448	464	* Look up a property in a node and return a pointer to its contents as a
449	465	* unsigned int array of given length. The property must have at least enough
450	466	* data for the array ('count' cells). It may have more, but this will be
...	...	@@ -485,6 +485,26 @@
485	485	return err;
486	486	}
487	487
	488	+int fdtdec_get_int_array_count(const void *blob, int node,
	489	+ const char prop_name, u32 array, int count)
	490	+{
	491	+ const u32 *cell;
	492	+ int len, elems;
	493	+ int i;
	494	+
	495	+ debug("%s: %s\n", __func__, prop_name);
	496	+ cell = fdt_getprop(blob, node, prop_name, &len);
	497	+ if (!cell)
	498	+ return -FDT_ERR_NOTFOUND;
	499	+ elems = len / sizeof(u32);
	500	+ if (count > elems)
	501	+ count = elems;
	502	+ for (i = 0; i < count; i++)
	503	+ array[i] = fdt32_to_cpu(cell[i]);
	504	+
	505	+ return count;
	506	+}
	507	+
488	508	const u32 fdtdec_locate_array(const void blob, int node,
489	509	const char *prop_name, int count)
490	510	{