Many boards have a bug-free ns16550 compatible serial port, which we should
register as PORT_16550A. This introduces a new value "ns16550a" for the
compatible property of of_serial to let a firmware choose that model instead
of using the crippled PORT_16550 mode.
Reported-by: NAlon Ziv <alonz@nolaviz.org>
Signed-off-by: NMichal Simek <monstr@monstr.eu>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>