Time: new clocksource

[Daniel Lezcano]

Hi Sekhar,

On 03/12/2021 17:50, Muni Sekhar wrote:
> Hi All,
> 
> We have a Digital PLL with 64 bit timer counter hardware and the
> counter is accessible from the CPU over the PCIe bus.
> 
> Is it possible to add this timer counter hardware as new clocksource
> driver? To do this, can someone please point me to the existing
> reference source code(or patch) for this task.

You can refer to the drivers located in drivers/clocksource

git annotate on one of the driver can give you the initial commit where
recent submissions explain the timer internals.

> Suppose if it is possible to add a new clocksource driver for this
> hardware then does any userspace get_timestamp* API would get the time
> from this new hardware?

It should if the timer is selected as the clocksource


-- 
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog