Always read the flash chip before writing

This will allow flashrom to skip erase of already-erased blocks and to
skip write of blocks which already have the wanted contents.

Avoid emergency messages by checking if the chip contents after a failed
write operation (erase/write) are unchanged.

Keep the emergency messages after a failed pure erase. That part is
debatable because if someone wants erase, he pretty sure doesn't care
about the flash contents anymore.

Please note that this introduces additional overhead of a full chip read
before write. This is frowned upon by people with slow programmers. A
followup patch will make this configurable.

Corresponding to flashrom svn r1215.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Stefan Reinauer <stepan@coreboot.org>
3 files changed