Currently QoS resume latencies are only considered for runtime PM
transitions of pmdomains, which remains the default.
In order to also support QoS resume latencies during system-wide PM,
add a new flag to indicate a resume latency should be used for
system-wide PM *in addition to* runtime PM.
If a user requires a different latency value for system-wide PM
compared to runtime PM, then the runtime PM value can be set for
normal operations, and the system-wide value (and flag) can be set by
during suspend (for example in a drivers ->prepare() hook) and the
runtime PM value can be restored after resume (for example, in a
driver's ->complete() hook.)
To: Rafael J. Wysocki <rafael@kernel.org>
To: Ulf Hansson <ulf.hansson@linaro.org>
To: linux-pm@vger.kernel.org
Signed-off-by: Kevin Hilman (TI) <khilman@baylibre.com>
---
Changes in v3:
- rebased to v7.0
- fix PREEMPT_RT: add new helper for lockless read of flags for atomic contexts
- update kerneldoc for genpd_for_each_child() as requested by Ulf
- Link to v2: https://patch.msgid.link/20260205-topic-lpm-pmdomain-device-constraints-v2-0-61f7be7d35ac@baylibre.com
Changes in v2:
- drop the userspace interface
- add genpd helper to iterate over all devices in domain and child domains
- new flag means latency applies to runtime PM *and* system-wide PM
- Link to v1: https://patch.msgid.link/20260120-topic-lpm-pmdomain-device-constraints-v1-0-108fc4cfafce@baylibre.com
---
Kevin Hilman (TI) (4):
PM / QoS: add flag to indicate latency applies system-wide
PM / QoS: add lockless read for flags
pmdomain: core: add genpd_for_each_child() helper
pmdomain: add support system-wide resume latency constraints
drivers/pmdomain/core.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
drivers/pmdomain/core.h | 17 +++++++++++++++++
drivers/pmdomain/governor.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/pm_qos.h | 9 +++++++++
4 files changed, 127 insertions(+)
---
base-commit: 3131ff5a117498bb4b9db3a238bb311cbf8383ce
change-id: 20260120-topic-lpm-pmdomain-device-constraints-e5e78ce48502
Best regards,
--
Kevin Hilman (TI) <khilman@baylibre.com>