RE: [PATCH V3 04/10] clk: imx: Support building SCU clock driver as module

[Anson Huang]

Hi, Arnd

> Subject: RE: [PATCH V3 04/10] clk: imx: Support building SCU clock driver as
> module
> 
> Hi, Arnd
> 
> > Subject: Re: [PATCH V3 04/10] clk: imx: Support building SCU clock
> > driver as module
> >
> > On Wed, Jul 1, 2020 at 9:19 AM Anson Huang <anson.huang@xxxxxxx>
> > wrote:
> > > > Subject: Re: [PATCH V3 04/10] clk: imx: Support building SCU clock
> > > > driver as module On Tue, Jun 30, 2020 at 5:16 AM Anson Huang
> > <anson.huang@xxxxxxx> wrote:
> > > >
> > > > SCU clock driver is a common driver for all SCU based platforms.
> > > > Current i.MX8QXP SCU clock driver will be extended to support all
> > > > future SCU based platforms.
> > > > So theoretically clk-scu.o and clk-imx8qxp.o can be combined. LPCG
> > > > is similar.
> > > > Maybe you can give a try as Arnd suggested.
> > > >
> > >
> > > Do we really need to link clk-scu and i.MX8QXP clock driver together
> > > just to
> > avoid some export?
> >
> > It was just meant to be easier than exporting a symbol and dealing
> > with module dependencies. If it's not easier, then don't.
> >
> > > I met some build issues if using this method, the i.MX8QXP module
> > > build is OK, but other platforms like
> > i.MX8MM/i.MX8MN/i.MX8MQ/i.MX8MP
> > > clock drivers are just skipped for build, even these i.MX8M clock
> > > config are existing in .config, anyone know why? Looks like the
> > > change in
> > Makefile for i.MX8QXP clock driver introduce this issue.
> >
> > You have a ":=" instead of "+=" typo, so all earlier "+=" are ignored:
> >
> > > obj-$(CONFIG_CLK_IMX8MM) += clk-imx8mm.o
> > > obj-$(CONFIG_CLK_IMX8MN) += clk-imx8mn.o
> > > obj-$(CONFIG_CLK_IMX8MP) += clk-imx8mp.o
> > > obj-$(CONFIG_CLK_IMX8MQ) += clk-imx8mq.o
> > >
> > > obj-$(CONFIG_MXC_CLK_SCU) := clk-imx-scu.o clk-imx-lpcg-scu.o
> >
> >                                    ^^^^^^^^
> 
> Thanks, I will give another try, I will make the common clk part all linked into
> each platform's clock driver, then many exports can be saved.

Just tried, it works for i.MX8QXP, andcorrect one thing, other platforms
need more complicated change if want to support them in the same way, so I
plan to ONLY do this change for i.MX8QXP if it is acceptable.

Thanks,
Anson