From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from hermes.mvista.com (gateway-1237.mvista.com [12.44.186.158]) by ozlabs.org (Postfix) with ESMTP id 190D668423 for ; Tue, 4 Oct 2005 06:46:40 +1000 (EST) Date: Mon, 3 Oct 2005 13:46:08 -0700 From: "Mark A. Greer" To: Corey Minyard Message-ID: <20051003204608.GC29005@mag.az.mvista.com> References: <20050929183221.GA17292@i2.minyard.local> <20050929203647.GA6597@mag.az.mvista.com> <433D557C.4020301@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <433D557C.4020301@acm.org> Cc: linuxppc-dev@ozlabs.org Subject: Re: MV64x60 watchdog timer driver updates List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Sep 30, 2005 at 10:10:52AM -0500, Corey Minyard wrote: > Mark A. Greer wrote: > > >On Thu, Sep 29, 2005 at 01:32:21PM -0500, Corey Minyard wrote: > > > > > >>James looked at an earlier version and said it was ok, and suggested > >>a few changes. This has been tested against 2.6.14-rc2 on a Katana. > >> > >>Note that the bus_clk value from the platform information seems to > >>be in MHZ, but the actual frequency is generally 133,333,333, not > >>133,000,000. I don't think the inaccuracy matters here, but it seems > >>a little odd. > >> > >> > > > >Yes, it makes more sense to me to pass the actual frequency and not do > >the '* 1000000'. > > > > > The only trouble is if you go over 4GHZ... Maybe it should be in KHZ > instead of MHZ? or 64-bits? Or maybe we don't worry about >4GHZ busses? My vote is to worry about it when the time comes. IIRC, the fastest a Marvell bridge part can be clocked right now is 200 MHz so there's some time. > Also, how would one go about changing this? Would you need something like: > > if (bus_clk < 1000) > bus_clk *= 1000000 > > for backwards compatability? When I didn't see anyone passing that value in via platform_data so there's no compatibility issue. I could have missed something though... > >Also--I should have thought of this earlier--there should probably be a > >patch to add a default platform_data entry in arch/ppc/syslib/mv64x60.c > >and a patch for katana.c if the defaults in mv64x60.c aren't correct > >for the katana. At least, that's how things are done now. > > > > > I'm not sure I understand completely. How would you go about setting > the platform data? Look near the top of arch/ppc/syslib/mv64x60.c and you will see a bunch of default platform_data being set up for marvell bridges. They can then be tweaked by the platform specific code via the platform_notify() hook (see arch/ppc/platforms/katana.c:katana_platform_notify(), et. al.). Mark