From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757366AbYKURRT (ORCPT ); Fri, 21 Nov 2008 12:17:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756234AbYKURQv (ORCPT ); Fri, 21 Nov 2008 12:16:51 -0500 Received: from relay2.sgi.com ([192.48.179.30]:42134 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756198AbYKURQu (ORCPT ); Fri, 21 Nov 2008 12:16:50 -0500 Date: Fri, 21 Nov 2008 11:16:49 -0600 From: Dimitri Sivanich To: "H. Peter Anvin" , Ingo Molnar , Andrew Morton Cc: Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/2 v3] SGI RTC: add clocksource/clockevent driver and generic timer vector Message-ID: <20081121171649.GB12370@sgi.com> References: <20081023163041.GA14574@sgi.com> <20081119212202.GA3377@sgi.com> <20081120095943.GF6885@elte.hu> <49261276.10408@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <49261276.10408@zytor.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 20, 2008 at 05:44:22PM -0800, H. Peter Anvin wrote: > Ingo Molnar wrote: > > * Dimitri Sivanich wrote: > > > >> The following patches provide a driver for synchronized RTC > >> clocksource and clockevents for SGI systems, as well as a generic > >> timer system interrupt. > >> > >> With these patches, a module can be installed that registers the > >> system-wide synchronized RTC clocksource and timers as both a > >> clocksource and clockevents device running in high resolution mode. > >> > >> [PATCH 1/2 v3] SGI RTC: add clocksource driver > >> [PATCH 2/2 v3] SGI RTC: add generic timer system interrupt > > > > Looks very clean and well-done to me. > > > > I had to take a good look at the rtc_timer_head->expires[] construct - > > but i guess that's the best approach, as the max number of entries is > > hard to judge at build time. (and we wont get any real limit > > protection from gcc anyway) > > > > Thomas, any objections? > > I have *extremely* serious reservations about reserving even more > hardware vectors for SGI only. This affects all systems, and quite > frankly should not be necessary at all. > > The SGI UV people have pushed this at a number of points in the past, > and we have told them to use an irqchip instead. This patch tries to > allocate yet another reserved vector, instead. I labeled the system vector as generic to indicate that this is available to other platforms. See my other email to you for the reasons why I did not use an irq instead.