Re: [PATCH v2 1/9] PM: domains: Delete usage of driver_deferred_probe_check_state()

Alexander Stein
2022-06-23T12:08:47Z

Hi,

Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> Hi,
>
> * Saravana Kannan <saravanak@google.com> [700101 02:00]:
> > Now that fw_devlink=on by default and fw_devlink supports
> > "power-domains" property, the execution will never get to the point
> > where driver_deferred_probe_check_state() is called before the supplier
> > has probed successfully or before deferred probe timeout has expired.
> >
> > So, delete the call and replace it with -ENODEV.
>
> Looks like this causes omaps to not boot in Linux next. With this
> simple-pm-bus fails to probe initially as the power-domain is not
> yet available. On platform_probe() genpd_get_from_provider() returns
> -ENOENT.
>
> Seems like other stuff is potentially broken too, any ideas on
> how to fix this?

I think I'm hit by this as well, although I do not get a lockup.
In my case I'm using arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts
and probing of 38320000.blk-ctrl fails as the power-domain is not (yet)
registed. See the (filtered) dmesg output:

> [ 0.744245] PM: Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@0 [ 0.744756] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@2 [ 0.745012] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@3 [ 0.745268] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@4 [ 0.746121] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@7 [ 0.746400] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@8 [ 0.746665] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@9 [ 0.746927] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@a [ 0.748870]
> imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV: failed to attach bus power
> domain [ 1.265279] PM: Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@5 [ 1.265861] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@6

blk-ctrl@38320000 requires the power-domain 'pgc_vpu', which is power-domain@6
in pgc.

Best regards,
Alexander

> > Signed-off-by: Saravana Kannan <saravanak@google.com>
> > ---
> >
> > drivers/base/power/domain.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> > index 739e52cd4aba..3e86772d5fac 100644
> > --- a/drivers/base/power/domain.c
> > +++ b/drivers/base/power/domain.c
> > @@ -2730,7 +2730,7 @@ static int __genpd_dev_pm_attach(struct device *dev,
> > struct device *base_dev,>
> > mutex_unlock(&gpd_list_lock);
> > dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
> >
> > __func__, PTR_ERR(pd));
> >
> > - return driver_deferred_probe_check_state(base_dev);
> > + return -ENODEV;
> >
> > }
> >
> > dev_dbg(dev, "adding to PM domain %s\n", pd->name);