From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 21 Sep 2007 16:43:21 +1000 From: David Gibson To: Paul Mackerras Subject: Re: [PATCH v2 2/4] Implement generic time of day clocksource for powerpc machines. Message-ID: <20070921064321.GA13740@localhost.localdomain> References: <20070921032603.07AF232C889@thor> <1190347546.15347.27.camel@imap.mvista.com> <18163.20403.967082.774118@cargo.ozlabs.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <18163.20403.967082.774118@cargo.ozlabs.ibm.com> Cc: Daniel Walker , Thomas Gleixner , Realtime Kernel , linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Sep 21, 2007 at 02:59:31PM +1000, Paul Mackerras wrote: > Daniel Walker writes: > > > I don't think the RTC frequency isn't the same as the timebase? Seems > > like the RTC only case about seconds at the lowest level. If that's the > > case then the jiffies clock might be better to use .. The other thing I > > wonder is if the __USE_RTC boards might have lower level clocks that > > could be used instead .. > > It's OK, the RTC isn't what you think it is, it's a pair of > CPU-internal registers which count seconds and nanoseconds. On > processors with the RTC, tb_ticks_per_sec is initialized to > 1000000000. Trust me, this code is OK. :) Indeed.. I'm wondering if we should do a s/rtc/ppc601rtc/ or something. Otherwise people will keep making this mistake and be confused. -- 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