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PM: domains: Fixup QoS latency measurements for IRQ safe devices in genpd

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When an IRQ safe device is attached to a non-IRQ safe PM domain, genpd
needs to prevent the PM domain from being powered off. However, genpd still
allows the device to be runtime suspended/resumed, hence it's also
reasonable to think that a governor may be used to validate the QoS latency
constraints.

Unfortunately, genpd_runtime_resume() treats the configuration above, as a
reason to skip measuring the QoS resume latency for the device. This is a
legacy behaviour that was earlier correct, but should have been changed
when genpd was transformed into its current behaviour around how it manages
IRQ safe devices. Luckily, there's no report about problems, so let's just
fixup the behaviour.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Ulf Hansson 2022-05-11 16:56:59 +02:00 committed by Rafael J. Wysocki
parent 3b84bf3ce9
commit a294237aea
1 changed files with 1 additions and 3 deletions
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4
drivers/base/power/domain.c
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@ -970,10 +970,8 @@ static int genpd_runtime_resume(struct device *dev)
* As we don't power off a non IRQ safe domain, which holds
* an IRQ safe device, we don't need to restore power to it.
*/
if (irq_safe_dev_in_sleep_domain(dev, genpd)) {
timed = false;
if (irq_safe_dev_in_sleep_domain(dev, genpd))
goto out;
}
genpd_lock(genpd);
ret = genpd_power_on(genpd, 0);