Provide the RW boot device operations for the common cbfs
SPI wrapper. The RW region_device is the same as the read-only
one. As noted in the boot_device_rw() introduction patch the
mmap() support should not be used in conjuction with writing
as that results in incoherent operations. That's fine as the
current mmap() support is only used in the cbfs layer which
does not support writing, i.e. no cbfs regions would be
written to with any previous or outstanding mmap() calls.
BUG=chrome-os-partner:56151
Change-Id: I7cc7309a68ad23b30208ac961b1999a79626b307
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/16199
Tested-by: build bot (Jenkins)
Reviewed-by: Furquan Shaikh <furquan@google.com>
504b8f2da2