From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 8 Apr 2008 12:44:40 +1000 From: David Gibson To: Josh Boyer Subject: Re: [PATCH 2/3] [POWERPC][V3] Xilinx: of_serial support for Xilinx uart 16550. Message-ID: <20080408024440.GB17820@localhost.localdomain> References: <20080402232213.5D87515B8067@mail37-sin.bigfish.com> <200804030134.11437.arnd@arndb.de> <200804030616.09825.arnd@arndb.de> <1207406756.6809.2.camel@vader.jdub.homelinux.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1207406756.6809.2.camel@vader.jdub.homelinux.org> Cc: linuxppc-dev@ozlabs.org, paulus@samba.org, John Linn , Arnd Bergmann List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sat, Apr 05, 2008 at 09:45:56AM -0500, Josh Boyer wrote: > On Thu, 2008-04-03 at 06:16 +0200, Arnd Bergmann wrote: > > On Thursday 03 April 2008, Grant Likely wrote: > > > > > > > > Since it is not really compatible with ns16550, shouldn't you at least specify > > > > a different "compatible" property? That way, the driver won't do incorrect > > > > accesses when you try to use an old driver with a device tree that specifies > > > > one of these. > > > > > > Heh; we've gone back and forth on this issue. The problem is that we > > > have a common case of ns16550 like devices that require a little bit > > > of register address tweaking that spans a whole range of vendors (so > > > adding a compatible match with each of those vendor's prefixes is > > > probably non-scalable). So, if "ns16550" is not a good idea, then > > > what should be used? "sparse16550" has been suggested more than once. > > > > After another IRC discussion between Grant, Segher and myself, we concluded > > that we don't need to invent a new "compatible" value, as only new device > > trees with old kernels will have a problem with this, and they don't work > > in the first place. > > > > The devices will still have their specific "compatible" value, e.g. > > "xlnx,plb-uart16550-1.00.c", followed by "ns16550", and possibly > > "ns16450" and "i8250", although the last two do not have an effect > > on Linux. > > > > Josh, can you please forward all three patches in their latest version? > > > > Acked-by: Arnd Bergmann > > So is the discussion on reg-offset settled then? It seemed Paul and > David had some issues with that, and I'd like to make sure everyone is > agreed on that before I bring in patches 2 and 3. I didn't like it very much, but I don't really care enough to argue about it. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson