Re: [PATCH v3] pinctrl: spacemit: enable config option

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

Hi Yixun,

On Mon, 17 Mar 2025 at 14:30, Yixun Lan <dlan@xxxxxxxxxx> wrote:
> On 13:59 Mon 17 Mar     , Geert Uytterhoeven wrote:
> > On Mon, 17 Mar 2025 at 13:41, Yixun Lan <dlan@xxxxxxxxxx> wrote:
> > > On 09:18 Mon 17 Mar     , Geert Uytterhoeven wrote:
> > > > Thanks for your patch, which is now commit 7ff4faba63571c51
> > > > ("pinctrl: spacemit: enable config option") in v6.14-rc7.
> > > >
> > > > On Tue, 18 Feb 2025 at 01:32, Yixun Lan <dlan@xxxxxxxxxx> wrote:
> > > > > Pinctrl is an essential driver for SpacemiT's SoC,
> > > > > The uart driver requires it, same as sd card driver,
> > > > > so let's enable it by default for this SoC.
> > > > >
> > > > > The CONFIG_PINCTRL_SPACEMIT_K1 isn't enabled when using
> > > > > 'make defconfig' to select kernel configuration options.
> > > > > This result in a broken uart driver where fail at probe()
> > > > > stage due to no pins found.
> > > >
> > > > Perhaps this is an issue with the uart driver?
> > > > I just disabled CONFIG_PINCTRL_RZA2 on RZA2MEVB (which is one of the
> > > > few Renesas platforms where the pin control driver is not enabled by
> > > > default, for saving memory), and the system booted fine into a Debian
> > > > nfsroot.  Probe order of some devices did change, and "Trying to
> > > > probe devices needed for running init" was printed.
> > > >
> > > my problem was CONFIG_PINCTRL_SPACEMIT_K1 isn't enabled, result as
> > > # CONFIG_PINCTRL_SPACEMIT_K1 is not set
> > >
> > > for your case, is CONFIG_PINCTRL_RZA2 built as module?
> > > it should work for uart driver with deferred probe mechanism..
> >
> > No, CONFIG_PINCTRL_RZA2 was disabled in my testing.
> >
> emm, this is interesting, there might be problem that uart driver
> fail to have correct pin settings without pre initialization..
>
> which uart driver is used in RZA2MEVB platform? any pinctrl dts property?
> different hardware may vary..

It indeed depends on both hardware and firmware.
RZA2MEVB uses the sh-sci driver, and its serial console is set up
by the boot loader.

Does your serial console work with "earlycon"?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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