Subject: Re: [PATCH] Handle reg-shift property for of_serial ports

From: Arnd Bergmann <[email-masked]>
Date: Sat, 7 Jul 2007 14:10:14 +0200

On Saturday 07 July 2007, David Woodhouse wrote:
> 
> The MV64660 has reg-shift==2 for its otherwise 16550-compatible uarts.
> While the bootwrapper copes with this, of_serial.c doesn't. (The udbg
> code doesn't either, but I'll fix that later).
> 
> Signed-off-by: David Woodhouse <[email-masked]>

Acked-by: Arnd Bergmann <[email-masked]>

Given the existence of the boards, it looks correct to do this.
However, I wonder if it was correct for the MV64660 to claim
compatibily witn ns16550 if the programming model is not exactly
the same. The official OF serial port bindings don't mention the
reg-shift property, so it maybe would have been better to have
a different value for the "compatible" property, in order not
to confuse existing operating systems that implement the standard.

Also, what about etherboot and yaboot? Do they handle this
correctly?

	Arnd <><