1 files changed, 14 insertions, 0 deletions
diff --git a/tools/binman/etype/x86_start16.py b/tools/binman/etype/x86_start16.py
index 23d27f0704..7d32ecd321 100644
--- a/tools/binman/etype/x86_start16.py
+++ b/tools/binman/etype/x86_start16.py
@@ -9,6 +9,20 @@ from entry import Entry
 from blob import Entry_blob
 
 class Entry_x86_start16(Entry_blob):
+    """x86 16-bit start-up code for U-Boot
+
+    Properties / Entry arguments:
+        - filename: Filename of u-boot-x86-16bit.bin (default
+            'u-boot-x86-16bit.bin')
+
+    x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
+    must be placed at a particular address. This entry holds that code. It is
+    typically placed at offset CONFIG_SYS_X86_START16. The code is responsible
+    for changing to 32-bit mode and jumping to U-Boot's entry point, which
+    requires 32-bit mode (for 32-bit U-Boot).
+
+    For 64-bit U-Boot, the 'x86_start16_spl' entry type is used instead.
+    """
     def __init__(self, section, etype, node):
         Entry_blob.__init__(self, section, etype, node)