Re: [PATCH v3 4/5] can: flexcan: update Kconfig to allow non-of cases

Geert Uytterhoeven
2021-06-22T06:52:32Z

Hi Marc,

On Mon, Jun 21, 2021 at 10:41 PM Marc Kleine-Budde <mkl@pengutronix.de> wrote:
> On 21.06.2021 22:22:50, Geert Uytterhoeven wrote:
> > On Mon, Jun 21, 2021 at 10:18 PM Marc Kleine-Budde <mkl@pengutronix.de> wrote:
> > > On 21.06.2021 22:11:58, Geert Uytterhoeven wrote:
> > > > On Mon, Jun 21, 2021 at 8:47 PM Angelo Dureghello
> > > > <angelo@kernel-space.org> wrote:
> > > > > Update flexcan to support architectures without fdt.
> > > > >
> > > > > Signed-off-by: Angelo Dureghello <angelo@kernel-space.org>

> > > > > --- a/drivers/net/can/Kconfig
> > > > > +++ b/drivers/net/can/Kconfig
> > > > > @@ -97,7 +97,7 @@ config CAN_AT91
> > > > >
> > > > > config CAN_FLEXCAN
> > > > > tristate "Support for Freescale FLEXCAN based chips"
> > > > > - depends on OF && HAS_IOMEM
> > > > > + depends on HAS_IOMEM
> > > >
> > > > I think you want to add a line
> > > >
> > > > depends on ARCH_LAYERSCAPE || ARCH_MXC || COLDFIRE ||
> > > > FSL_SOC_BOOKE || COMPILE_TEST
> > > >
> > > > (or PPC instead of FSL_SOC_BOOKE?)
> > > > so the question doesn't pop up when compiling a kernel for a system
> > > > that cannot have a Freescale FlexCAN IP block.
> > >
> > > Back in 2018 Pankaj Bansal replaced the "depends on ARM || PPC" by "OF
> > > && HAS_IOMEM", see:
> > >
> > > | 0f8af56f74cd can: flexcan: enable flexcan for all architectures
> >
> > Probably the real reason behind that was to enable it on ARM64
> > (more specifically ARCH_LAYERSCAPE || ARCH_MXC).
>
> Probably. What about the original proposed change: "(OF || M5441x) && HAS_IOMEM"?

Yeah, the Flexcan might pop up on RISC-V, too.
But any new platforms should use OF.
Given the Flexcan is probably present on more than just M5441x,
I'd go for:

depends on OF || COLDFIRE || COMPILE_TEST
depends on HAS_IOMEM

> > > So I think there won't be too many configs where the oldconfig question
> > > would pop up.
> >
> > Now it will, as Mr. Torvalds' main machine does not satisfy "ARM || PPC"
> > or "OF && HAS_IOMEM", but does "HAS_IOMEM" ;-)
>
> IC, that would be one question too much :)

I do doubt he has CONFIG_CAN enabled ;-)

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds