am335x: Add struct `am335x_uart` for uart registers

Add a struct for referencing UART registers. The layout is quite
strange on this chip, as the entire register space can take on three
different meanings depending on the line control settings (in the LCR
register) And to make things more confusing, some offsets reference
different registers depending on if a read or a write operation is
used.

Change-Id: Ie62af9c0e0edafd01b81686a0fe5c5c1d4fa06c4
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/3319
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
1 file changed