diff options
| author | Ulf Hansson <ulf.hansson@linaro.org> | 2024-05-27 16:25:51 +0200 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2024-08-05 13:12:04 +0200 |
| commit | d7bdb8e6aabe218fd980768a1486434e42761539 (patch) | |
| tree | a04ca728f0b95fa0a8e12fa92aacabebdf2e0cef /drivers/pmdomain | |
| parent | 328fc9b29810819c4496c6e9fd74491ca458045e (diff) | |
pmdomain: core: Enable s2idle for CPU PM domains on PREEMPT_RT
To allow a genpd provider for a CPU PM domain to enter a domain-idle-state
during s2idle on a PREEMPT_RT based configuration, we can't use the regular
spinlock, as they are turned into sleepable locks on PREEMPT_RT.
To address this problem, let's convert into using the raw spinlock, but
only for genpd providers that have the GENPD_FLAG_CPU_DOMAIN bit set. In
this way, the lock can still be acquired/released in atomic context, which
is needed in the idle-path for PREEMPT_RT.
Do note that the genpd power-on/off notifiers may also be fired during
s2idle, but these are already prepared for PREEMPT_RT as they are based on
the raw notifiers. However, consumers of them may need to adopt accordingly
to work properly on PREEMPT_RT.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Raghavendra Kakarla <quic_rkakarla@quicinc.com> # qcm6490 with PREEMPT_RT set
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20240527142557.321610-2-ulf.hansson@linaro.org
Diffstat (limited to 'drivers/pmdomain')
| -rw-r--r-- | drivers/pmdomain/core.c | 47 |
1 files changed, 46 insertions, 1 deletions
diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c index 7a61aa88c061..8c798a46ffec 100644 --- a/drivers/pmdomain/core.c +++ b/drivers/pmdomain/core.c @@ -117,6 +117,48 @@ static const struct genpd_lock_ops genpd_spin_ops = { .unlock = genpd_unlock_spin, }; +static void genpd_lock_raw_spin(struct generic_pm_domain *genpd) + __acquires(&genpd->raw_slock) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&genpd->raw_slock, flags); + genpd->raw_lock_flags = flags; +} + +static void genpd_lock_nested_raw_spin(struct generic_pm_domain *genpd, + int depth) + __acquires(&genpd->raw_slock) +{ + unsigned long flags; + + raw_spin_lock_irqsave_nested(&genpd->raw_slock, flags, depth); + genpd->raw_lock_flags = flags; +} + +static int genpd_lock_interruptible_raw_spin(struct generic_pm_domain *genpd) + __acquires(&genpd->raw_slock) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&genpd->raw_slock, flags); + genpd->raw_lock_flags = flags; + return 0; +} + +static void genpd_unlock_raw_spin(struct generic_pm_domain *genpd) + __releases(&genpd->raw_slock) +{ + raw_spin_unlock_irqrestore(&genpd->raw_slock, genpd->raw_lock_flags); +} + +static const struct genpd_lock_ops genpd_raw_spin_ops = { + .lock = genpd_lock_raw_spin, + .lock_nested = genpd_lock_nested_raw_spin, + .lock_interruptible = genpd_lock_interruptible_raw_spin, + .unlock = genpd_unlock_raw_spin, +}; + #define genpd_lock(p) p->lock_ops->lock(p) #define genpd_lock_nested(p, d) p->lock_ops->lock_nested(p, d) #define genpd_lock_interruptible(p) p->lock_ops->lock_interruptible(p) @@ -2143,7 +2185,10 @@ static void genpd_free_data(struct generic_pm_domain *genpd) static void genpd_lock_init(struct generic_pm_domain *genpd) { - if (genpd_is_irq_safe(genpd)) { + if (genpd_is_cpu_domain(genpd)) { + raw_spin_lock_init(&genpd->raw_slock); + genpd->lock_ops = &genpd_raw_spin_ops; + } else if (genpd_is_irq_safe(genpd)) { spin_lock_init(&genpd->slock); genpd->lock_ops = &genpd_spin_ops; } else { |