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-rw-r--r--include/fdtdec.h47
-rw-r--r--lib/fdtdec.c116
2 files changed, 163 insertions, 0 deletions
diff --git a/include/fdtdec.h b/include/fdtdec.h
index d871cdd..492431c 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -126,3 +126,50 @@ int fdtdec_get_is_enabled(const void *blob, int node, int default_val);
* if not.
*/
int fdtdec_check_fdt(void);
+
+/**
+ * Find the nodes for a peripheral and return a list of them in the correct
+ * order. This is used to enumerate all the peripherals of a certain type.
+ *
+ * To use this, optionally set up a /aliases node with alias properties for
+ * a peripheral. For example, for usb you could have:
+ *
+ * aliases {
+ * usb0 = "/ehci@c5008000";
+ * usb1 = "/ehci@c5000000";
+ * };
+ *
+ * Pass "usb" as the name to this function and will return a list of two
+ * nodes offsets: /ehci@c5008000 and ehci@c5000000.
+ *
+ * All nodes returned will match the compatible ID, as it is assumed that
+ * all peripherals use the same driver.
+ *
+ * If no alias node is found, then the node list will be returned in the
+ * order found in the fdt. If the aliases mention a node which doesn't
+ * exist, then this will be ignored. If nodes are found with no aliases,
+ * they will be added in any order.
+ *
+ * If there is a gap in the aliases, then this function return a 0 node at
+ * that position. The return value will also count these gaps.
+ *
+ * This function checks node properties and will not return nodes which are
+ * marked disabled (status = "disabled").
+ *
+ * @param blob FDT blob to use
+ * @param name Root name of alias to search for
+ * @param id Compatible ID to look for
+ * @param node_list Place to put list of found nodes
+ * @param maxcount Maximum number of nodes to find
+ * @return number of nodes found on success, FTD_ERR_... on error
+ */
+int fdtdec_find_aliases_for_id(const void *blob, const char *name,
+ enum fdt_compat_id id, int *node_list, int maxcount);
+
+/*
+ * Get the name for a compatible ID
+ *
+ * @param id Compatible ID to look for
+ * @return compatible string for that id
+ */
+const char *fdtdec_get_compatible(enum fdt_compat_id id);
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 0f87163..55d5bdf 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -35,6 +35,13 @@ DECLARE_GLOBAL_DATA_PTR;
static const char * const compat_names[COMPAT_COUNT] = {
};
+const char *fdtdec_get_compatible(enum fdt_compat_id id)
+{
+ /* We allow reading of the 'unknown' ID for testing purposes */
+ assert(id >= 0 && id < COMPAT_COUNT);
+ return compat_names[id];
+}
+
/**
* Look in the FDT for an alias with the given name and return its node.
*
@@ -132,6 +139,115 @@ int fdtdec_next_alias(const void *blob, const char *name,
return err ? -FDT_ERR_NOTFOUND : node;
}
+/* TODO: Can we tighten this code up a little? */
+int fdtdec_find_aliases_for_id(const void *blob, const char *name,
+ enum fdt_compat_id id, int *node_list, int maxcount)
+{
+ int name_len = strlen(name);
+ int nodes[maxcount];
+ int num_found = 0;
+ int offset, node;
+ int alias_node;
+ int count;
+ int i, j;
+
+ /* find the alias node if present */
+ alias_node = fdt_path_offset(blob, "/aliases");
+
+ /*
+ * start with nothing, and we can assume that the root node can't
+ * match
+ */
+ memset(nodes, '\0', sizeof(nodes));
+
+ /* First find all the compatible nodes */
+ for (node = count = 0; node >= 0 && count < maxcount;) {
+ node = fdtdec_next_compatible(blob, node, id);
+ if (node >= 0)
+ nodes[count++] = node;
+ }
+ if (node >= 0)
+ debug("%s: warning: maxcount exceeded with alias '%s'\n",
+ __func__, name);
+
+ /* Now find all the aliases */
+ memset(node_list, '\0', sizeof(*node_list) * maxcount);
+
+ for (offset = fdt_first_property_offset(blob, alias_node);
+ offset > 0;
+ offset = fdt_next_property_offset(blob, offset)) {
+ const struct fdt_property *prop;
+ const char *path;
+ int number;
+ int found;
+
+ node = 0;
+ prop = fdt_get_property_by_offset(blob, offset, NULL);
+ path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
+ if (prop->len && 0 == strncmp(path, name, name_len))
+ node = fdt_path_offset(blob, prop->data);
+ if (node <= 0)
+ continue;
+
+ /* Get the alias number */
+ number = simple_strtoul(path + name_len, NULL, 10);
+ if (number < 0 || number >= maxcount) {
+ debug("%s: warning: alias '%s' is out of range\n",
+ __func__, path);
+ continue;
+ }
+
+ /* Make sure the node we found is actually in our list! */
+ found = -1;
+ for (j = 0; j < count; j++)
+ if (nodes[j] == node) {
+ found = j;
+ break;
+ }
+
+ if (found == -1) {
+ debug("%s: warning: alias '%s' points to a node "
+ "'%s' that is missing or is not compatible "
+ " with '%s'\n", __func__, path,
+ fdt_get_name(blob, node, NULL),
+ compat_names[id]);
+ continue;
+ }
+
+ /*
+ * Add this node to our list in the right place, and mark
+ * it as done.
+ */
+ if (fdtdec_get_is_enabled(blob, node)) {
+ node_list[number] = node;
+ if (number >= num_found)
+ num_found = number + 1;
+ }
+ nodes[j] = 0;
+ }
+
+ /* Add any nodes not mentioned by an alias */
+ for (i = j = 0; i < maxcount; i++) {
+ if (!node_list[i]) {
+ for (; j < maxcount; j++)
+ if (nodes[j] &&
+ fdtdec_get_is_enabled(blob, nodes[j]))
+ break;
+
+ /* Have we run out of nodes to add? */
+ if (j == maxcount)
+ break;
+
+ assert(!node_list[i]);
+ node_list[i] = nodes[j++];
+ if (i >= num_found)
+ num_found = i + 1;
+ }
+ }
+
+ return num_found;
+}
+
/*
* This function is a little odd in that it accesses global data. At some
* point if the architecture board.c files merge this will make more sense.