efi_loader: TODO for the EFI file protocol

We currently only support EFI_FILE_PROTOCOL_REVISION while
UEFI specs 2.4 - 2.7 prescribe EFI_FILE_PROTOCOL_REVISION2.
Add a todo.

Add missing constants for the EFI file protocol revision.
Signed-off-by: NHeinrich Schuchardt <xypron.glpk@gmx.de>

doc/README.uefi

@@ -329,6 +329,9 @@ This driver is only available if U-Boot is configured with
   * persistence
   * runtime support
 
+* incompletely implemented protocols
+  * support version 0x00020000 of the EFI file protocol
+
 ## Links
 
 * [1](http://uefi.org/specifications)

include/efi_api.h

@@ -1322,7 +1322,9 @@ struct efi_pxe {
 #define EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID \
 	EFI_GUID(0x964e5b22, 0x6459, 0x11d2, \
 		 0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
-#define EFI_FILE_PROTOCOL_REVISION 0x00010000
+#define EFI_FILE_PROTOCOL_REVISION	0x00010000
+#define EFI_FILE_PROTOCOL_REVISION2	0x00020000
+#define EFI_FILE_PROTOCOL_LATEST_REVISION EFI_FILE_PROTOCOL_REVISION2
 
 struct efi_file_handle {
 	u64 rev;
@@ -1346,6 +1348,10 @@ struct efi_file_handle {
 			const efi_guid_t *info_type, efi_uintn_t buffer_size,
 			void *buffer);
 	efi_status_t (EFIAPI *flush)(struct efi_file_handle *file);
+	/*
+	 * TODO: We currently only support EFI file protocol revision 0x00010000
+	 *	 while UEFI specs 2.4 - 2.7 prescribe revision 0x00020000.
+	 */
 };
 
 #define EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_REVISION 0x00010000

lib/efi_loader/efi_file.c

@@ -628,6 +628,10 @@ static efi_status_t EFIAPI efi_file_flush(struct efi_file_handle *file)
 }
 
 static const struct efi_file_handle efi_file_handle_protocol = {
+	/*
+	 * TODO: We currently only support EFI file protocol revision 0x00010000
+	 *	 while UEFI specs 2.4 - 2.7 prescribe revision 0x00020000.
+	 */
 	.rev = EFI_FILE_PROTOCOL_REVISION,
 	.open = efi_file_open,
 	.close = efi_file_close,