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

From: Anson Huang
Date: Tue Jun 25 2019 - 21:42:56 EST

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?