Add some utilities to manipulate the reserved memory map.
diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c
index 2711324..af33336 100644
--- a/libfdt/fdt_ro.c
+++ b/libfdt/fdt_ro.c
@@ -329,3 +329,75 @@
return tag;
}
+
+/*
+ * Return the number of used reserve map entries and total slots available.
+ */
+int fdt_num_reservemap(void *fdt, int *used, int *total)
+{
+ struct fdt_reserve_entry *re;
+ int start;
+ int end;
+ int err = fdt_check_header(fdt);
+
+ if (err != 0)
+ return err;
+
+ start = fdt_off_mem_rsvmap(fdt);
+
+ /*
+ * Convention is that the reserve map is before the dt_struct,
+ * but it does not have to be.
+ */
+ end = fdt_totalsize(fdt);
+ if (end > fdt_off_dt_struct(fdt))
+ end = fdt_off_dt_struct(fdt);
+ if (end > fdt_off_dt_strings(fdt))
+ end = fdt_off_dt_strings(fdt);
+
+ /*
+ * Since the reserved area list is zero terminated, you get one fewer.
+ */
+ if (total)
+ *total = ((end - start) / sizeof(struct fdt_reserve_entry)) - 1;
+
+ if (used) {
+ *used = 0;
+ while (start < end) {
+ re = (struct fdt_reserve_entry *)(fdt + start);
+ if (re->size == 0)
+ return 0; /* zero size terminates the list */
+
+ *used += 1;
+ start += sizeof(struct fdt_reserve_entry);
+ }
+ /*
+ * If we get here, there was no zero size termination.
+ */
+ return -FDT_ERR_BADLAYOUT;
+ }
+ return 0;
+}
+
+/*
+ * Return the nth reserve map entry.
+ */
+int fdt_get_reservemap(void *fdt, int n, struct fdt_reserve_entry *re)
+{
+ int used;
+ int total;
+ int err;
+
+ err = fdt_num_reservemap(fdt, &used, &total);
+ if (err != 0)
+ return err;
+
+ if (n >= total)
+ return -FDT_ERR_NOSPACE;
+ if (re) {
+ *re = *(struct fdt_reserve_entry *)
+ _fdt_offset_ptr(fdt, n * sizeof(struct fdt_reserve_entry));
+ }
+ return 0;
+}
+
