Re: [PATCH v21 01/13] clocksource: arm_arch_timer: introduce two functions to get the frequency from mmio and sysreg.

From	Mark Rutland <mark.rutland@arm.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v21 01/13] clocksource: arm_arch_timer: introduce two functions to get the frequency from mmio and sysreg.
Date	2017-03-17 19:10 +0100
Message-ID	<tm4u6-21N-33@gated-at.bofh.it> (permalink)
References	<t7WG5-ld-3@gated-at.bofh.it> <t7WG6-ld-19@gated-at.bofh.it>
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On Tue, Feb 07, 2017 at 02:50:03AM +0800, fu.wei@linaro.org wrote:
> +static u32 arch_timer_get_sysreg_freq(void)
> +{
> +	/*
> +	 * Try to get the frequency from the CNTFRQ of sysreg.
> +	 */
> +	return arch_timer_get_cntfrq();
> +}

We already have arch_timer_get_cntfrq(), so I don't see the point in
this wrapper.

> +static u32 arch_timer_get_mmio_freq(void __iomem *cntbase)
> +{
> +	/*
> +	 * Try to get the frequency from the CNTFRQ of timer frame registers.
> +	 * Note: please verify cntbase in caller.
> +	 */
> +	return readl_relaxed(cntbase + CNTFRQ);
> +}

Wrapping the MMIO read makes sense if we're going to do this in more
than one place, so I'm happy with this wrapper.

If you can s/arch_timer_get_mmio_freq/arch_timer_get_cntfrq/, and drop
the comments, then this looks fine to me.

Thanks,
Mark.

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Re: [PATCH v21 01/13] clocksource: arm_arch_timer: introduce two  functions to get the frequency from mmio and sysreg. Mark Rutland <mark.rutland@arm.com> - 2017-03-17 19:10 +0100
  Re: [PATCH v21 01/13] clocksource: arm_arch_timer: introduce two  functions to get the frequency from mmio and sysreg. Fu Wei <fu.wei@linaro.org> - 2017-03-20 08:40 +0100
    Re: [PATCH v21 01/13] clocksource: arm_arch_timer: introduce two  functions to get the frequency from mmio and sysreg. Fu Wei <fu.wei@linaro.org> - 2017-03-20 10:50 +0100
      Re: [PATCH v21 01/13] clocksource: arm_arch_timer: introduce two  functions to get the frequency from mmio and sysreg. Mark Rutland <mark.rutland@arm.com> - 2017-03-20 11:50 +0100
        Re: [PATCH v21 01/13] clocksource: arm_arch_timer: introduce two  functions to get the frequency from mmio and sysreg. Fu Wei <fu.wei@linaro.org> - 2017-03-20 12:20 +0100

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