dm: core: Add a function to decode a memory region

Add a way to decode a memory region, including the memory type (sram or
sdram) and its start address and size.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 45 insertions, 0 deletions

diff --git a/include/dm/of_extra.h b/include/dm/of_extra.h
index e1540c1..97988b6 100644
--- a/include/dm/of_extra.h
+++ b/include/dm/of_extra.h
@@ -40,4 +40,49 @@ struct fmap_entry {
  */
 int ofnode_read_fmap_entry(ofnode node, struct fmap_entry *entry);
 
+/**
+ * ofnode_decode_region() - Decode a memory region from a node
+ *
+ * Look up a property in a node which contains a memory region address and
+ * size. Then return a pointer to this address.
+ *
+ * The property must hold one address with a length. This is only tested on
+ * 32-bit machines.
+ *
+ * @param node		ofnode to examine
+ * @param prop_name	name of property to find
+ * @param basep		Returns base address of region
+ * @param size		Returns size of region
+ * @return 0 if ok, -1 on error (property not found)
+ */
+int ofnode_decode_region(ofnode node, const char *prop_name, fdt_addr_t *basep,
+			 fdt_size_t *sizep);
+
+/**
+ * ofnode_decode_memory_region()- Decode a named region within a memory bank
+ *
+ * This function handles selection of a memory region. The region is
+ * specified as an offset/size within a particular type of memory.
+ *
+ * The properties used are:
+ *
+ *	<mem_type>-memory<suffix> for the name of the memory bank
+ *	<mem_type>-offset<suffix> for the offset in that bank
+ *
+ * The property value must have an offset and a size. The function checks
+ * that the region is entirely within the memory bank.5
+ *
+ * @param node		ofnode containing the properties (-1 for /config)
+ * @param mem_type	Type of memory to use, which is a name, such as
+ *			"u-boot" or "kernel".
+ * @param suffix	String to append to the memory/offset
+ *			property names
+ * @param basep		Returns base of region
+ * @param sizep		Returns size of region
+ * @return 0 if OK, -ive on error
+ */
+int ofnode_decode_memory_region(ofnode config_node, const char *mem_type,
+				const char *suffix, fdt_addr_t *basep,
+				fdt_size_t *sizep);
+
 #endif