doc: description of board_get_usable_ram_top()
Improve the description of function board_get_usable_ram_top().
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/include/init.h b/include/init.h
index 8873081..dc3c1f2 100644
--- a/include/init.h
+++ b/include/init.h
@@ -296,13 +296,18 @@
int show_board_info(void);
/**
- * Get the uppermost pointer that is valid to access
+ * board_get_usable_ram_top() - get uppermost address for U-Boot relocation
*
- * Some systems may not map all of their address space. This function allows
- * boards to indicate what their highest support pointer value is for DRAM
- * access.
+ * Some systems have reserved memory areas in high memory. By implementing this
+ * function boards can indicate the highest address value to be used when
+ * relocating U-Boot. The returned address is exclusive (i.e. 1 byte above the
+ * last usable address).
+ *
+ * Due to overflow on systems with 32bit phys_addr_t a value 0 is used instead
+ * of 4GiB.
*
- * @param total_size Size of U-Boot (unused?)
+ * @total_size: monitor length in bytes (size of U-Boot code)
+ * Return: uppermost address for U-Boot relocation
*/
phys_size_t board_get_usable_ram_top(phys_size_t total_size);