Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268501AbUIPQ7v (ORCPT ); Thu, 16 Sep 2004 12:59:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268368AbUIPQzk (ORCPT ); Thu, 16 Sep 2004 12:55:40 -0400 Received: from atlrel7.hp.com ([156.153.255.213]:13761 "EHLO atlrel7.hp.com") by vger.kernel.org with ESMTP id S268490AbUIPQzG (ORCPT ); Thu, 16 Sep 2004 12:55:06 -0400 From: Bjorn Helgaas To: Christoph Lameter Subject: Re: device driver for the SGI system clock, mmtimer Date: Thu, 16 Sep 2004 10:54:51 -0600 User-Agent: KMail/1.6.2 Cc: linux-kernel@vger.kernel.org, Jesse Barnes , Bob Picco , venkatesh.pallipadi@intel.com References: <200409161003.39258.bjorn.helgaas@hp.com> In-Reply-To: MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200409161054.51467.bjorn.helgaas@hp.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1463 Lines: 32 On Thursday 16 September 2004 10:32 am, Christoph Lameter wrote: > On Thu, 16 Sep 2004, Bjorn Helgaas wrote: > > Christoph Lameter wrote: > > > The timer hardware was designed around the multimedia timer specification by Intel > > > but to my knowledge only SGI has implemented that standard. The driver was written > > > by Jesse Barnes. > > > > As far as I can see, drivers/char/hpet.c talks to the same hardware. > > HP sx1000 machines (and probably others) also implement the HPET. > > The Intel Multimedia Standard is a earlier and different timer spec. I have a spec that's labelled "IA-PC Multimedia Timers", preliminary draft of June 2000, revision 0.97, which looks like the one mentioned in your patch. I also have something labelled "IA-PC HPET (High Precision Event Timers) Specification", draft of February 2002, revision 0.98, which is what drivers/char/hpet.c supports. I admit I haven't compared them in great detail, but they certainly *look* like they're close enough that the same driver could support both, and the 0.98 revision history only mentions fairly cosmetic changes (like the name :)). Is there something specific that drivers/char/hpet.c expects that your hardware doesn't implement? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/