doc: FIT image: Introduce "u-boot, fpga-legacy" property

Commit 4afc4f37c70e ("doc: FIT image: Clarify format and simplify
syntax") introduced a "compatible" property for loadable images.
It did not define its contents. Use "u-boot,fpga-legacy" compatible
string to specify that fpga_load() should be used to load the image.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

diff --git a/doc/uImage.FIT/source_file_format.txt b/doc/uImage.FIT/source_file_format.txt
index 00ed3eb..f93ac6d 100644 (file)
--- a/doc/uImage.FIT/source_file_format.txt
+++ b/doc/uImage.FIT/source_file_format.txt
@@ -184,6 +184,7 @@ the '/images' node should have the following layout:
     Mandatory for types: "firmware", and "kernel".
   - compatible : compatible method for loading image.
     Mandatory for types: "fpga", and images that do not specify a load address.
+    To use the generic fpga loading routine, use "u-boot,fpga-legacy".
 
   Optional nodes:
   - hash-1 : Each hash sub-node represents separate hash or checksum