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

Fu Wei fu.wei at linaro.org
Mon Mar 20 04:09:56 PDT 2017


Hi Mark,

On 20 March 2017 at 18:41, Mark Rutland <mark.rutland at arm.com> wrote:
> On Mon, Mar 20, 2017 at 05:43:29PM +0800, Fu Wei wrote:
>> On 20 March 2017 at 15:36, Fu Wei <fu.wei at linaro.org> wrote:
>> > On 18 March 2017 at 02:05, Mark Rutland <mark.rutland at arm.com> wrote:
>> >> On Tue, Feb 07, 2017 at 02:50:03AM +0800, fu.wei at linaro.org wrote:
>
>> >>> +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
>> >
>> > sorry, May I guess that is
>> > "s/arch_timer_get_mmio_freq/arch_timer_get_mmio_cntfrq/"
>> > or
>> > "s/arch_timer_get_mmio_freq/arch_timer_mem_get_cntfrq/"
>> >
>> > which one do you prefer? :-)
>>
>> keeping using arch_timer_get_cntfrq();  for per-CPU arch timer, then
>>
>> +static u32 arch_timer_mem_get_cntfrq(void __iomem *cntbase)
>> +{
>> +       return readl_relaxed(cntbase + CNTFRQ);
>> +}
>> +
>
> That looks perfect to me.
>
> Sorry for the confusion above!

Great, thanks , doing this way :-)

>
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat



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