fmap: Add FMAP_AREA_PRESERVE

When updating firmware, we may need to preserve some sections like VPD,
calibration data, ... etc. The logic can be hard-coded in updater as a
list of known names, but a better solution is to have that directly
declared inside FMAP area flags.

To do that, the first step is to apply the changes in flash map
(http://crosreview.com/1493767). A new FMAP_AREA_PRESERVE is now
defined and will be set in future with new syntax in FMD parser.

BUG=chromium:936768
TEST=make; boots an x86 image.

Change-Id: Idba5c8d4a4c5d272f22be85d2054c6c0ce020b1b
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: https://review.coreboot.org/c/31676
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

payloads/libpayload/include/fmap_serialized.h

@@ -48,6 +48,7 @@ enum fmap_flags {
 	FMAP_AREA_STATIC	= 1 << 0,
 	FMAP_AREA_COMPRESSED	= 1 << 1,
 	FMAP_AREA_RO		= 1 << 2,
+	FMAP_AREA_PRESERVE	= 1 << 3,
 };
 
 /* Mapping of volatile and static regions in firmware binary */

src/commonlib/include/commonlib/fmap_serialized.h

@@ -48,6 +48,7 @@ enum fmap_flags {
 	FMAP_AREA_STATIC	= 1 << 0,
 	FMAP_AREA_COMPRESSED	= 1 << 1,
 	FMAP_AREA_RO		= 1 << 2,
+	FMAP_AREA_PRESERVE	= 1 << 3,
 };
 
 /* Mapping of volatile and static regions in firmware binary */

util/cbfstool/flashmap/fmap.c

@@ -59,6 +59,7 @@ const struct valstr flag_lut[] = {
 	{ FMAP_AREA_STATIC, "static" },
 	{ FMAP_AREA_COMPRESSED, "compressed" },
 	{ FMAP_AREA_RO, "ro" },
+	{ FMAP_AREA_PRESERVE, "preserve" },
 };
 
 /* returns size of fmap data structure if successful, <0 to indicate error */

util/cbfstool/flashmap/fmap.h

@@ -49,6 +49,7 @@ enum fmap_flags {
 	FMAP_AREA_STATIC	= 1 << 0,
 	FMAP_AREA_COMPRESSED	= 1 << 1,
 	FMAP_AREA_RO		= 1 << 2,
+	FMAP_AREA_PRESERVE	= 1 << 3,
 };
 
 /* Mapping of volatile and static regions in firmware binary */