Re: [PATCH 9/9] clocksource: import ARC timer driver

From	Daniel Lezcano <daniel.lezcano@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH 9/9] clocksource: import ARC timer driver
Date	2016-11-03 18:40 +0100
Message-ID	<szu9F-6WS-13@gated-at.bofh.it> (permalink)
References	<syp2h-5zh-25@gated-at.bofh.it> <sytyV-8o-5@gated-at.bofh.it> <sytyW-8o-33@gated-at.bofh.it> <syOal-57X-7@gated-at.bofh.it> <syOk1-5bc-3@gated-at.bofh.it>
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On Tue, Nov 01, 2016 at 01:57:05PM -0700, Vineet Gupta wrote:
> Hi Daniel,
> 
> On 11/01/2016 01:42 PM, Daniel Lezcano wrote:
> > Please stay consistent with the rest of the Kconfig.
> > 
> > config ARC_TIMER_RTC
> > 	bool "64-bit cycle counter in HS38 cores" if COMPILE_TEST
> > 	select CLKSRC_OF
> > 	help
> > 	  This counter provides 64-bit resolution vs. the 32-bit TIMER1.
> > 	  It is implemented inside the core thus can't be used in SMP systems.
> > 
> > config ARC_TIMER_GFRC
> > 	bool "64-bit cycle counter in ARConnect block in HS38x cores" if COMPILE_TEST
> > 	select CLKSRC_OF
> > 	help
> > 	  This counter can be used as clocksource in SMP HS38 SoCs.
> > 	  It sits outside the core thus can be used in SMP systems
> > 
> 
> Yes I did so already :-) Although I also added a default y if ARC to both, but as
> you say that is better done in ARC Kconfig.
> 
> > Then in the ARC's Kconfig you select ARC_TIMER_RTC or ARC_TIMER_GFRC depending
> > it is SMP or not.
> > 
> > One question:
> > 
> > Why ARC_TIMER_RTC can't be used in a SMP system ? Doesn't have each core its
> > own clocksource ? It seems you are assuming a clocksource can be used on SMP
> > only if the clocksource is unique and shared across the cores.
> 

As now the clksrc-probe is correctly handling the errors, if the rtc and the
gfrc are both defined in the DT, you can fail to init the rtc one with a simple
test in the init function:

	if (IS_DEFINED(CONFIG_SMP))
		return -EINVAL;

So, you can inconditionaly compile in both RTC and GFRC, no ? That would be
cleaner and prevent a different kernel config.

Thread

Re: [PATCH v2 3/3] clocksource: Add clockevent support to NPS400  driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-10-31 12:00 +0100
  Re: [PATCH v2 3/3] clocksource: Add clockevent support to NPS400  driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 19:00 +0100
    [PATCH 7/9] ARC: breakout timer stuff into a seperate header Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
      Re: [PATCH 7/9] ARC: breakout timer stuff into a seperate header Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:30 +0100
    [PATCH 5/9] ARC: breakout aux handling into a seperate header Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
      RE: [PATCH 5/9] ARC: breakout aux handling into a seperate header Noam Camus <noamca@mellanox.com> - 2016-11-01 10:30 +0100
    [PATCH 3/9] ARC: timer: gfrc: boot print alongside other timers Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
      Re: [PATCH 3/9] ARC: timer: gfrc: boot print alongside other timers Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:20 +0100
        Re: [PATCH 3/9] ARC: timer: gfrc: boot print alongside other timers Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-03 18:50 +0100
          Re: [PATCH 3/9] ARC: timer: gfrc: boot print alongside other timers Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 19:00 +0100
    [PATCH 1/9] ARC: timer: gfrc, rtc: Read BCR to detect whether hardware exists ... Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
      Re: [PATCH 1/9] ARC: timer: gfrc, rtc: Read BCR to detect whether  hardware exists ... Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:10 +0100
        Re: [PATCH 1/9] ARC: timer: gfrc, rtc: Read BCR to detect whether  hardware exists ... Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-03 18:50 +0100
    [PATCH 8/9] ARC: timer: rename config options Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
    [PATCH 0/9] Move ARC timer code into drivers/clocksource/ Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
      [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
        Re: [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-01 01:50 +0100
        Re: [PATCH 9/9] clocksource: import ARC timer driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-01 21:50 +0100
          Re: [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-01 22:00 +0100
            Re: [PATCH 9/9] clocksource: import ARC timer driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-02 01:30 +0100
              Re: [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-02 02:10 +0100
                Re: [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-03 17:50 +0100
                Re: [PATCH 9/9] clocksource: import ARC timer driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:00 +0100
                Re: [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-03 19:00 +0100
                Re: [PATCH 9/9] clocksource: import ARC timer driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 19:20 +0100
                Re: [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-03 19:50 +0100
            Re: [PATCH 9/9] clocksource: import ARC timer driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:40 +0100
              Re: [PATCH 9/9] clocksource: import ARC timer driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 19:20 +0100
              Re: [PATCH 9/9] clocksource: import ARC timer driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-03 20:00 +0100
      [PATCH 4/9] ARC: time: move time_init() out of the driver Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-10-31 23:50 +0100
        Re: [PATCH 4/9] ARC: time: move time_init() out of the driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:20 +0100
      [PATCH 6/9] ARC: move mcip.h into include/soc and adjust the includes Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-01 00:00 +0100
        Re: [PATCH 6/9] ARC: move mcip.h into include/soc and adjust the  includes Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:30 +0100
      [PATCH 2/9] ARC: timer: rtc: implement read loop in "C" vs. inline asm Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-01 00:00 +0100
        Re: [PATCH 2/9] ARC: timer: rtc: implement read loop in "C" vs.  inline asm Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:10 +0100
          Re: [PATCH 2/9] ARC: timer: rtc: implement read loop in "C" vs.  inline asm Vineet Gupta <Vineet.Gupta1@synopsys.com> - 2016-11-03 18:50 +0100
      Re: [PATCH 0/9] Move ARC timer code into drivers/clocksource/ Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-03 18:30 +0100
  RE: [PATCH v2 3/3] clocksource: Add clockevent support to NPS400  driver Noam Camus <noamca@mellanox.com> - 2016-11-01 01:40 +0100
    Re: [PATCH v2 3/3] clocksource: Add clockevent support to NPS400  driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-01 21:10 +0100
      RE: [PATCH v2 3/3] clocksource: Add clockevent support to NPS400  driver Noam Camus <noamca@mellanox.com> - 2016-11-08 12:10 +0100
        Re: [PATCH v2 3/3] clocksource: Add clockevent support to NPS400  driver Daniel Lezcano <daniel.lezcano@linaro.org> - 2016-11-10 11:40 +0100
          RE: [PATCH v2 3/3] clocksource: Add clockevent support to NPS400  driver Noam Camus <noamca@mellanox.com> - 2016-11-10 14:10 +0100

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