[PATCH V2 3/9] clk: imx: Support building SCU clock driver as module

[Stephen Boyd]

Quoting Arnd Bergmann (2020-06-29 01:19:44)
> On Mon, Jun 29, 2020 at 9:18 AM Dong Aisheng <dongas86 at gmail.com> wrote:
> > On Thu, Jun 25, 2020 at 6:43 AM Stephen Boyd <sboyd at kernel.org> wrote:
> > > Quoting Aisheng Dong (2020-06-23 19:59:09)
> > > Why aren't there options to enable clk-imx6q and clk-imx6sl in the
> > > clk/imx/Kconfig file? Those can be bool or tristate depending on if the
> > > SoC drivers use CLK_OF_DECLARE or not and depend on the mxc-clk library
> > > and SoC config we have in the makefile today.
> >
> > Yes, we can do that in clk/imx/Kconfig as follows theoretically.
> > config CLK_IMX6Q
> >         bool
> >         def_bool ARCH_MXC && ARM
> >         select MXC_CLK
> >
> > But we have totally 15 platforms that need to change.
> 
> I would make that
> 
> config CLK_IMX6Q
>          bool "Clock driver for NXP i.MX6Q"
>          depends on SOC_IMX6Q || COMPILE_TEST
>          default SOC_IMX6Q
>          select MXC_CLK

Yes, do this.

> 
> > e.g.
> > drivers/clk/imx/Makefile
> > obj-$(CONFIG_SOC_IMX1)   += clk-imx1.o
> > obj-$(CONFIG_SOC_IMX21)  += clk-imx21.o
> > obj-$(CONFIG_SOC_IMX25)  += clk-imx25.o
> > obj-$(CONFIG_SOC_IMX27)  += clk-imx27.o
> > obj-$(CONFIG_SOC_IMX31)  += clk-imx31.o
> > obj-$(CONFIG_SOC_IMX35)  += clk-imx35.o
> > obj-$(CONFIG_SOC_IMX5)   += clk-imx5.o
> > obj-$(CONFIG_SOC_IMX6Q)  += clk-imx6q.o
> > obj-$(CONFIG_SOC_IMX6SL) += clk-imx6sl.o
> > obj-$(CONFIG_SOC_IMX6SLL) += clk-imx6sll.o
> > obj-$(CONFIG_SOC_IMX6SX) += clk-imx6sx.o
> > obj-$(CONFIG_SOC_IMX6UL) += clk-imx6ul.o
> > obj-$(CONFIG_SOC_IMX7D)  += clk-imx7d.o
> > obj-$(CONFIG_SOC_IMX7ULP) += clk-imx7ulp.o
> > obj-$(CONFIG_SOC_VF610)  += clk-vf610.o
> >
> > Not sure if it's really worth to do that.
> > The easiest way to address this issue is just select it in
> > arch/arm/mach-imx/Kconfig,
> 
> Changing them can be a one or two patches, that's totally
> worth it IMHO.

Agreed.

> 
> I really don't like the 'select' in arch/arm/mach-imx/Kconfig: if
> you've done the work to make the imx8 clk driver modular,
> I would expect to see the same at least tried for the other
> ones.

Agreed.

> 
> For the clk drivers that cannot yet be 'tristate' because of the
> CLK_OF_DECLARE(), can you include a list of drivers
> that depend on the clocks being available during early
> boot?
>