Re: [PATCH v1] riscv: dts: starfive: move timebase-frequency to .dtsi

[Conor Dooley]

On Fri, Dec 01, 2023 at 02:44:58PM +0100, Emil Renner Berthing wrote:
> Conor Dooley wrote:
> > From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> >
> > Properties fixed by the SoC should be defined in the $soc.dtsi, and the
> > timebase-frequency is not sourced directly from an off-chip oscillator.
> 
> Yes, according to the JH7100 docs[1] the mtime register is sourced from the
> osc_sys external oscillator through u74rtc_toggle. However I haven't yet found
> a place in the docs that describe where that clock is divided by 4 to get
> 6.25MHz from the 25MHz.
> 
> I expect the JH7110 mtime is set up in a similar way, but haven't yet dug into
> the available documentation.

Your other reply suggests that this is a fixed division for the jh7110,
in which case it makes sense to leave it as-is. mpfs is different in
that it is fixed to 1 MHz regardless of which of the permitted external
oscillator frequencies you use.

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