[U-Boot] [PATCH 1/2] doc: FIT image: clarify usage of "compression" property

[Simon Goldschmidt]

Compressed images should have their compression property
set to "none" if U-Boot should leave them compressed.

This is especially the case for compressed ramdisks that
should be uncompressed by the kernel only.

Signed-off-by: Simon Goldschmidt <sgoldschmidt at de.pepperl-fuchs.com>
---

 doc/uImage.FIT/source_file_format.txt | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/doc/uImage.FIT/source_file_format.txt b/doc/uImage.FIT/source_file_format.txt
index d2793a195d..d701b9bb76 100644
--- a/doc/uImage.FIT/source_file_format.txt
+++ b/doc/uImage.FIT/source_file_format.txt
@@ -164,7 +164,9 @@ the '/images' node should have the following layout:
   - data : Path to the external file which contains this node's binary data.
   - compression : Compression used by included data. Supported compressions
     are "gzip" and "bzip2". If no compression is used compression property
-    should be set to "none".
+    should be set to "none". If the data is compressed but it should not be
+    uncompressed by U-Boot (e.g. compressed ramdisk), this should also be set
+    to "none".
 
   Conditionally mandatory property:
   - os : OS name, mandatory for types "kernel" and "ramdisk". Valid OS names
-- 
2.11.0