Am Mittwoch, dem 24.08.2022 um 15:30 +0200 schrieb Ulf Hansson: > On Mon, 22 Aug 2022 at 10:38, Martin Kepplinger > <martin.kepplinger@xxxxxxx> wrote: > > > > Am Freitag, dem 19.08.2022 um 16:53 +0200 schrieb Ulf Hansson: > > > On Fri, 19 Aug 2022 at 11:17, Martin Kepplinger > > > <martin.kepplinger@xxxxxxx> wrote: > > > > > > > > Am Dienstag, dem 26.07.2022 um 17:07 +0200 schrieb Ulf Hansson: > > > > > On Tue, 26 Jul 2022 at 10:33, Martin Kepplinger > > > > > <martin.kepplinger@xxxxxxx> wrote: > > > > > > > > > > > > If for example the power-domains' power-supply node > > > > > > (regulator) > > > > > > needs > > > > > > interrupts to work, the current setup with noirq callbacks > > > > > > cannot > > > > > > work; for example a pmic regulator on i2c, when suspending, > > > > > > usually > > > > > > already > > > > > > times out during suspend_noirq: > > > > > > > > > > > > [ 41.024193] buck4: failed to disable: -ETIMEDOUT > > > > > > > > > > > > So fix system suspend and resume for these power-domains by > > > > > > using > > > > > > the > > > > > > "outer" suspend/resume callbacks instead. Tested on the > > > > > > imx8mq- > > > > > > librem5 board, > > > > > > but by looking at the dts, this will fix imx8mq-evk and > > > > > > possibly > > > > > > many other > > > > > > boards too. > > > > > > > > > > > > This is designed so that genpd providers just say "this > > > > > > genpd > > > > > > needs > > > > > > interrupts" (by setting the flag) - without implying an > > > > > > implementation. > > > > > > > > > > > > Initially system suspend problems had been discussed at > > > > > > https://lore.kernel.org/linux-arm-kernel/20211002005954.1367653-8-l.stach@xxxxxxxxxxxxxx/ > > > > > > which led to discussing the pmic that contains the > > > > > > regulators > > > > > > which > > > > > > serve as power-domain power-supplies: > > > > > > https://lore.kernel.org/linux-pm/573166b75e524517782471c2b7f96e03fd93d175.camel@xxxxxxx/T/ > > > > > > > > > > > > Signed-off-by: Martin Kepplinger > > > > > > <martin.kepplinger@xxxxxxx> > > > > > > --- > > > > > > drivers/base/power/domain.c | 13 +++++++++++-- > > > > > > include/linux/pm_domain.h | 5 +++++ > > > > > > 2 files changed, 16 insertions(+), 2 deletions(-) > > > > > > > > > > > > diff --git a/drivers/base/power/domain.c > > > > > > b/drivers/base/power/domain.c > > > > > > index 5a2e0232862e..58376752a4de 100644 > > > > > > --- a/drivers/base/power/domain.c > > > > > > +++ b/drivers/base/power/domain.c > > > > > > @@ -130,6 +130,7 @@ static const struct genpd_lock_ops > > > > > > genpd_spin_ops = { > > > > > > #define genpd_is_active_wakeup(genpd) (genpd->flags & > > > > > > GENPD_FLAG_ACTIVE_WAKEUP) > > > > > > #define genpd_is_cpu_domain(genpd) (genpd->flags & > > > > > > GENPD_FLAG_CPU_DOMAIN) > > > > > > #define genpd_is_rpm_always_on(genpd) (genpd->flags & > > > > > > GENPD_FLAG_RPM_ALWAYS_ON) > > > > > > +#define genpd_irq_on(genpd) (genpd->flags & > > > > > > GENPD_FLAG_IRQ_ON) > > > > > > > > > > > > static inline bool irq_safe_dev_in_sleep_domain(struct > > > > > > device > > > > > > *dev, > > > > > > const struct generic_pm_domain *genpd) > > > > > > @@ -2065,8 +2066,15 @@ int pm_genpd_init(struct > > > > > > generic_pm_domain > > > > > > *genpd, > > > > > > genpd->domain.ops.runtime_suspend = > > > > > > genpd_runtime_suspend; > > > > > > genpd->domain.ops.runtime_resume = > > > > > > genpd_runtime_resume; > > > > > > genpd->domain.ops.prepare = genpd_prepare; > > > > > > - genpd->domain.ops.suspend_noirq = > > > > > > genpd_suspend_noirq; > > > > > > - genpd->domain.ops.resume_noirq = > > > > > > genpd_resume_noirq; > > > > > > + > > > > > > + if (genpd_irq_on(genpd)) { > > > > > > + genpd->domain.ops.suspend = > > > > > > genpd_suspend_noirq; > > > > > > + genpd->domain.ops.resume = > > > > > > genpd_resume_noirq; > > > > > > + } else { > > > > > > + genpd->domain.ops.suspend_noirq = > > > > > > genpd_suspend_noirq; > > > > > > + genpd->domain.ops.resume_noirq = > > > > > > genpd_resume_noirq; > > > > > > > > > > As we discussed previously, I am thinking that it may be > > > > > better > > > > > to > > > > > move to using genpd->domain.ops.suspend_late and > > > > > genpd->domain.ops.resume_early instead. > > > > > > > > Wouldn't that better be a separate patch (on top)? Do you > > > > really > > > > want > > > > me to change the current behaviour (default case) to from noirq > > > > to > > > > late? Then I'll resend this series with such a patch added. > > > > > > Sorry, I wasn't clear enough, the default behaviour should remain > > > as > > > is. > > > > > > What I meant was, when genpd_irq_on() is true, we should use the > > > genpd->domain.ops.suspend_late and genpd- > > > >domain.ops.resume_early. > > > > Testing that shows that this isn't working. I can provide the logs > > later, but suspend fails and I think it makes sense: "suspend_late" > > is > > simply already too late when i2c (or any needed driver) uses > > "suspend". > > Okay, I see. > > The reason why I suggested moving the callbacks to "suspend_late", > was > that I was worried that some of the attached devices to genpd could > use "suspend_late" themselves. This is the case for some drivers for > DMA/clock/gpio/pinctrl-controllers, for example. That said, I am > curious to look at the DT files for the platform you are running, > would you mind giving me a pointer? I'm running https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi with these (small) patches on top: https://source.puri.sm/martin.kepplinger/linux-next/-/commits/5.19.3/librem5 > > So, this made me think about this a bit more. In the end, just using > different levels (suspend, suspend_late, suspend_noirq) of callbacks > are just papering over the real *dependency* problem. true, it doesn't feel like a stable solution. > > What we need for the genpd provider driver, is to be asked to be > suspended under the following conditions: > 1. All consumer devices (and child-domains) for its corresponding PM > domain have been suspended. > 2. All its supplier devices supplies must remain resumed, until the > genpd provider has been suspended. > > Please allow me a few more days to think in more detail about this. Thanks a lot for thinking about this! > > In some way, it looks like we should be able to combine the > information genpd has about its devices and child-domains, use PM > callbacks for the genpd provider driver - so we can rely on the > depency-path the fw_devlinks would give us for its supplier devices. > > Kind regards > Uffe martin
