Re: [PATCH RESEND V2 1/3] clocksource/drivers/sysctr: Add optional clock-frequency property

From: Daniel Lezcano
Date: Wed Jun 26 2019 - 06:38:17 EST


On 26/06/2019 03:42, Anson Huang wrote:
> Hi, Daniel
>
>> On 23/06/2019 14:38, Anson.Huang@xxxxxxx wrote:
>>> From: Anson Huang <Anson.Huang@xxxxxxx>
>>>
>>> Systems which use platform driver model for clock driver require the
>>> clock frequency to be supplied via device tree when system counter
>>> driver is enabled.
>>>
>>> This is necessary as in the platform driver model the of_clk
>>> operations do not work correctly because system counter driver is
>>> initialized in early phase of system boot up, and clock driver using
>>> platform driver model is NOT ready at that time, it will cause system
>>> counter driver initialization failed.
>>>
>>> Add the optinal clock-frequency to the device tree bindings of the NXP
>>> system counter, so the frequency can be handed in and the of_clk
>>> operations can be skipped.
>>
>> Isn't it possible to create a fixed-clock and refer to it? So no need to create a
>> specific action before calling timer_of_init() ?
>>
>
> As the clock must be ready before the TIMER_OF_DECLARE, so adding a CLK_OF_DECLARE_DRIVER in
> clock driver to ONLY register a fixed-clock? The system counter's frequency are different on different
> platforms, so adding fixed clock in system counter driver is NOT a good idea, ONLY the DT node or the
> clock driver can create this fixed clock according to platforms, can you advise where to create this fixed
> clock is better?

Can you point me to a DT with the "nxp,sysctr-timer" ?


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