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

[Alexander Stein]

Hi,

Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> Hi,
> 
> * Saravana Kannan <saravanak@xxxxxxxxxx> [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@xxxxxxxxxx>
> > ---
> > 
> >  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);