Re: [PATCH v5 2/2] mfd: simple-mfd-i2c: add a reboot cell for the SpacemiT P1 chip

Aurelien Jarno
2026-03-02T20:09:10Z

Hi,

On 2026-03-01 23:16, Aurelien Jarno wrote:
> On 2026-02-27 13:29, Yanko Kaneti wrote:
> > On Thu, 2026-02-26 at 22:32 +0100, Aurelien Jarno wrote:
> > > Hi,
> > >
> > > On 2026-02-26 16:32, Yanko Kaneti wrote:
> > > > Hello,
> > > >
> > > > On Mon, 2025-11-03 at 00:02 +0100, Aurelien Jarno wrote:
> > > > > Add a "spacemit-p1-reboot" cell for the SpacemiT P1 chip.
> > > > >
> > > > > Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
> > > > > ---
> > > > > v5: no changes
> > > > >
> > > > > drivers/mfd/simple-mfd-i2c.c | 1 +
> > > > > 1 file changed, 1 insertion(+)
> > > > >
> > > > > diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
> > > > > index 0a607a1e3ca1d..542d378cdcd1f 100644
> > > > > --- a/drivers/mfd/simple-mfd-i2c.c
> > > > > +++ b/drivers/mfd/simple-mfd-i2c.c
> > > > > @@ -99,6 +99,7 @@ static const struct regmap_config spacemit_p1_regmap_config = {
> > > > > };
> > > > >
> > > > > static const struct mfd_cell spacemit_p1_cells[] = {
> > > > > + { .name = "spacemit-p1-reboot", },
> > > > > { .name = "spacemit-p1-regulator", },
> > > > > { .name = "spacemit-p1-rtc", },
> > > > > };
> > > >
> > > > Perhaps its safe to merge this one now that everything P1 and I2C is
> > > > already in linus tip ?
> > >
> > > Unfortunately, this patchset is still missing:
> > > https://lore.kernel.org/all/20260207-b4-k3-i2c-pio-v7-0-626942d94d91@linux.spacemit.com/
> > >
> > > This means the reboots work most of the time, but are not 100% reliable,
> > > and that's the reason why this patch got blocked from merging.
> >
> > I see. Thanks. Sounds to me like sometimes working compared to never
> > working is better , but anyway..
>
> I agree with that, but the decision was to hold on this patch until the
> I2C PIO part got merged.
>
> > FWIW with this patch and the pio patcheset I get this rcu splat on
> > reboot (which is still working). Similar splat is there without the pio
> > patcheset.
>
> I haven't been able to reproduce the issue here after 10+ reboots on a
> BPI-F3 board, but I tried the patch on top of 6.19. I'll try to build a
> 7.0.0-rc2 kernel and report back.

I have tried that, and I am still unable to reproduce the issue with a
7.0.0-rc2 kernel and a BPI-F3 board.

Regards
Aurelien

--
Aurelien Jarno GPG: 4096R/1DDD8C9B
aurelien@aurel32.net http://aurel32.net