Re: [RFC PATCH 2/2] PM / devfreq: rk3399_dmc: Block PMU during transitions

[Chanwoo Choi]

On 22. 4. 14. 08:13, Chanwoo Choi wrote:
> On 22. 4. 14. 07:45, Heiko Stübner wrote:
> > Hi,
> >
> > Am Donnerstag, 14. April 2022, 00:14:40 CEST schrieb Chanwoo Choi:
> > > On 22. 4. 6. 10:48, Brian Norris wrote:
> > > > See the previous patch ("soc: rockchip: power-domain: Manage resource
> > > > conflicts with firmware") for a thorough explanation of the conflicts.
> > > > While ARM Trusted Firmware may be modifying memory controller and
> > > > power-domain states, we need to block the kernel's power-domain driver.
> > > >
> > > > If the power-domain driver is disabled, there is no resource conflict
> > > > and this becomes a no-op.
> > > >
> > > > Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
> > > > ---
> > > >
> > > >    drivers/devfreq/rk3399_dmc.c | 13 +++++++++++++
> > > >    1 file changed, 13 insertions(+)
> > > >
> > > > diff --git a/drivers/devfreq/rk3399_dmc.c 
> > > > b/drivers/devfreq/rk3399_dmc.c
> > > > index e494d1497d60..daff40702615 100644
> > > > --- a/drivers/devfreq/rk3399_dmc.c
> > > > +++ b/drivers/devfreq/rk3399_dmc.c
> > > > @@ -21,6 +21,7 @@
> > > >    #include <linux/rwsem.h>
> > > >    #include <linux/suspend.h>
> > > > +#include <soc/rockchip/pm_domains.h>
> > > >    #include <soc/rockchip/rk3399_grf.h>
> > > >    #include <soc/rockchip/rockchip_sip.h>
> > > > @@ -93,6 +94,16 @@ static int rk3399_dmcfreq_target(struct device 
> > > > *dev, unsigned long *freq,
> > > >        mutex_lock(&dmcfreq->lock);
> > > > +    /*
> > > > +     * Ensure power-domain transitions don't interfere with ARM 
> > > > Trusted
> > > > +     * Firmware power-domain idling.
> > > > +     */
> > > > +    err = rockchip_pmu_block();
> > > > +    if (err) {
> > > > +        dev_err(dev, "Failed to block PMU: %d\n", err);
> > > > +        goto out_unlock;
> > > > +    }
> > > > +
> > > >        /*
> > > >         * Some idle parameters may be based on the DDR controller 
> > > > clock, which
> > > >         * is half of the DDR frequency.
> > > > @@ -198,6 +209,8 @@ static int rk3399_dmcfreq_target(struct device 
> > > > *dev, unsigned long *freq,
> > > >        dmcfreq->volt = target_volt;
> > > >    out:
> > > > +    rockchip_pmu_unblock();
> > > > +out_unlock:
> > > >        mutex_unlock(&dmcfreq->lock);
> > > >        return err;
> > > >    }
> > >
> > > Acked-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> >
> > so I guess you're ok with me picking up both patches, right?
> > [Just making sure :-) ]
>
> This patch have the dependency of latest devfreq-next branch.
> So that need to make the immutable branch between rockchip and devfreq.

Hi Heiko and Brian,

Is there any other progress?

IMHO, if rockchip maintainer reply the acked-by from patch1
and then agree these patches to be applied to devfreq.git,
I can take them.

--
Best Regards,
Samsung Electronics
Chanwoo Choi