From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Ungerer Subject: Re: [PATCH] m68k/coldfire/pit: set ->min_delta_ticks and ->max_delta_ticks Date: Fri, 31 Mar 2017 11:10:46 +1000 Message-ID: <5b67c049-804b-403b-1799-60ba85483267__15522.2785113894$1490923212$gmane$org@linux-m68k.org> References: <20170326134403.16226-1-nicstange@gmail.com> <20170330194431.6978-1-nicstange@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170330194431.6978-1-nicstange@gmail.com> Sender: linux-m68k-owner@vger.kernel.org List-Id: linux-m68k@vger.kernel.org To: Nicolai Stange , Geert Uytterhoeven Cc: John Stultz , linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org Hi Nicolai, On 31/03/17 05:44, Nicolai Stange wrote: > In preparation for making the clockevents core NTP correction aware, > all clockevent device drivers must set ->min_delta_ticks and > ->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a > clockevent device's rate is going to change dynamically and thus, the > ratio of ns to ticks ceases to stay invariant. > > Make the m68k arch's coldfire clockevent driver initialize these fields > properly. > > This patch alone doesn't introduce any change in functionality as the > clockevents core still looks exclusively at the (untouched) ->min_delta_ns > and ->max_delta_ns. As soon as this has changed, a followup patch will > purge the initialization of ->min_delta_ns and ->max_delta_ns from this > driver. > > Signed-off-by: Nicolai Stange Looks ok to me. Acked-by: Greg Ungerer Are you pushing this through some other git tree? Or do you want me to push up to Linus? Regards Greg > --- > > Notes: > This prerequisite patch is part of a larger effort to feed NTP > corrections into the clockevent devices' frequencies and thus > avoiding their notion of time to diverge from the system's > one. If you're interested, the current state of the whole series > can be found at [1]. > > If you haven't got any objections and these prerequisites get > merged by 4.12 everywhere, I'll proceed with the remainder of > this series in 4.13. > > Applicable to next-20170324 as well as to John' Stultz tree [2]. > > [1] > git://nicst.de/linux.git cev-freq-adj.v10.fortglx-4.12-time > https://nicst.de/git/?p=linux.git;a=shortlog;h=refs/heads/cev-freq-adj.v10.fortglx-4.12-time > > [2] > https://git.linaro.org/people/john.stultz/linux.git fortglx/4.12/time > > arch/m68k/coldfire/pit.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/m68k/coldfire/pit.c b/arch/m68k/coldfire/pit.c > index 175553d5b8ed..6c0878018b44 100644 > --- a/arch/m68k/coldfire/pit.c > +++ b/arch/m68k/coldfire/pit.c > @@ -149,8 +149,10 @@ void hw_timer_init(irq_handler_t handler) > cf_pit_clockevent.mult = div_sc(FREQ, NSEC_PER_SEC, 32); > cf_pit_clockevent.max_delta_ns = > clockevent_delta2ns(0xFFFF, &cf_pit_clockevent); > + cf_pit_clockevent.max_delta_ticks = 0xFFFF; > cf_pit_clockevent.min_delta_ns = > clockevent_delta2ns(0x3f, &cf_pit_clockevent); > + cf_pit_clockevent.min_delta_ticks = 0x3f; > clockevents_register_device(&cf_pit_clockevent); > > setup_irq(MCF_IRQ_PIT1, &pit_irq); >