Re: [PATCH v1 15/30] clk: starfive: Use regmap APIs to operate registers

Hal Feng
2022-10-28T02:46:59Z

On Wed, 26 Oct 2022 18:26:03 -0700, Stephen Boyd wrote:
> Quoting Hal Feng (2022-10-22 21:11:41)
> > On Wed, 12 Oct 2022 16:05:23 -0700, Stephen Boyd wrote:
> > > I think we should use auxiliary bus and split the driver logically into
> > > a reset driver in drivers/reset and a clk driver in drivers/clk. That
> > > way the appropriate maintainers can review the code. There is only one
> > > platform device with a single reg property and node in DT, but there are
> > > two drivers.
> >
> > Yes, I agree that the reset driver and the clock driver should be split.
> > However, I think using auxiliary bus is a little bit complicated in this
> > case, because the reset is not a part of functionality of the clock in
> > JH7110. They just share a common register base address.
>
> That is why auxiliary bus exists.
>
> > I think it is
> > better to use ioremap for the same address, and the dt will be like
> >
> > syscrg_clk: clock-controller@13020000 {
> > compatible = "starfive,jh7110-clkgen-sys";
> > reg = <0x0 0x13020000 0x0 0x10000>;
> > ...
> > };
> > syscrg_rst: reset-controller@13020000 {
> > compatible = "starfive,jh7110-reset-sys";
> > reg = <0x0 0x13020000 0x0 0x10000>;
> > ...
> > };
> >
> > What do you think of this approach? I would appreciate your suggestions.
> >
>
> We shouldn't have two different nodes with the same reg property. Please
> ioremap in whatever driver probes and creates the auxiliary device(s)
> and then pass the void __iomem * to it.

Okay, I will use auxiliary bus for clock and reset driver on the next version.

Best regards,
Hal