From mboxrd@z Thu Jan 1 00:00:00 1970 From: Scott Wood Subject: Re: [PATCH v5 3/5] arm64: arch_timer: Work around QorIQ Erratum A-008585 Date: Thu, 22 Sep 2016 03:34:39 -0500 Message-ID: <1474533279.4283.32.camel@buserror.net> References: <1473469413-11019-1-git-send-email-oss@buserror.net> <1473469413-11019-3-git-send-email-oss@buserror.net> <20160912113615.GA20804@leverpostej> <1474260085.15220.17.camel@buserror.net> <20160919165258.GA30584@leverpostej> <1474304489.4283.6.camel@buserror.net> <20160919170707.GC30584@leverpostej> <1474312560.4283.10.camel@buserror.net> <20160920093503.GA1045@leverpostej> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20160920093503.GA1045@leverpostej> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mark Rutland Cc: Catalin Marinas , Will Deacon , Marc Zyngier , Shawn Guo , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stuart.yoder-3arQi8VN3Tc@public.gmane.org, mike.caraman-3arQi8VN3Tc@public.gmane.org, Ding Tianhong List-Id: devicetree@vger.kernel.org On Tue, 2016-09-20 at 10:35 +0100, Mark Rutland wrote: > On Mon, Sep 19, 2016 at 02:16:00PM -0500, Scott Wood wrote: > > > > On Mon, 2016-09-19 at 18:07 +0100, Mark Rutland wrote: > > > > > > > > > > > > > > > > > Reconsidering my suggestion, I realise this will also affect the > > > > > MMIO > > > > > timers, so that doesn't work. > > > > > > > > > > So for the moment, I guess we have to keep > > > > > fsl_a008585_set_next_event(). > > > > What is the problem with MMIO timers?  needs_fsl_a008585_workaround() > > > > should > > > > always be false for them. > > > As suggested, needs_fsl_a008585_workaround() takes no parameter, and > > > set_next_event is called for both cp15/sysreg and MMIO timers. So it > > > would either be true for all, or false for all. > > > > > > If it's true for all, we'd end up calling fsl_a008585_set_next_event() > > > for the MMIO timers too. > > There should not be any MMIO timers on a system where > > fsl_a008585_set_next_event() returns true. > I'm generally not keen on relying on that. > > For reference, are no MMIO timers implemented at all, or are they simply > not listed in the DT today? As far as I can tell they're not implemented, but it's possible I'm just not looking at the right documentation.   I agree though that depending on that isn't particularly pretty.  I'll stick with the current approach for set_next_event(). -Scott -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html