| Message ID | 1466624209-27432-2-git-send-email-lina.iyer@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jun 22, 2016 at 01:36:36PM -0600, Lina Iyer wrote: > From: Axel Haslam <ahaslam+renesas@baylibre.com> > > This patch allows domains to define idle states in the DT. SoC's can > define domain idle states in DT using the "power-states" property of the > domain provider. Calling of_pm_genpd_init() will read the idle states > and initialize the genpd for the domain. > > In addition to the entry and exit latency for idle state, also add > residency and state-param properties. A domain idling in a state is only > power effecient if it stays idle for a certain period in that state. The > residency provides this minimum time for the idle state to provide power > benefits. The state-param is a state specific u32 value that the > platform may use for that idle state. > > Signed-off-by: Marc Titinger <mtitinger+renesas@baylibre.com> > Signed-off-by: Lina Iyer <lina.iyer@linaro.org> > [Lina: Added state properties, removed state names, wakeup-latency, > added of_pm_genpd_init() API, pruned commit text] > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> > [Ulf: Moved around code to make it compile properly, rebased on top of multiple > state support,changed to use pm_genpd_init()] > --- > drivers/base/power/domain.c | 84 ++++++++++++++++++++++++++++++++++++++++++++- > include/linux/pm_domain.h | 3 ++ > 2 files changed, 86 insertions(+), 1 deletion(-) > > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c > index a1f2aff..62ffabd 100644 > --- a/drivers/base/power/domain.c > +++ b/drivers/base/power/domain.c > @@ -1253,6 +1253,82 @@ out: > } > EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain); > > +static int genpd_of_get_power_state(struct genpd_power_state *genpd_state, > + struct device_node *state_node) > +{ > + int err = 0; > + u32 latency; > + u32 residency; > + u32 param; > + u32 entry_latency, exit_latency; > + > + err = of_property_read_u32(state_node, "entry-latency-us", > + &entry_latency); > + if (err) { > + pr_debug(" * %s missing entry-latency-us property\n", > + state_node->full_name); > + return -EINVAL; > + } > + > + err = of_property_read_u32(state_node, "exit-latency-us", > + &exit_latency); > + if (err) { > + pr_debug(" * %s missing exit-latency-us property\n", > + state_node->full_name); > + return -EINVAL; > + } > + > + err = of_property_read_u32(state_node, "residency-us", &residency); > + if (!err) > + genpd_state->residency_ns = 1000 * residency; > + > + err = of_property_read_u32(state_node, "state-param", ¶m); > + if (!err) > + genpd_state->param = param; > + > + latency = entry_latency + exit_latency; > + genpd_state->power_on_latency_ns = 1000 * latency; > + genpd_state->power_off_latency_ns = 1000 * entry_latency; > + > + return 0; > +} As with the binding, I would very much prefer that this were unfiied with the existing idle state parsing. I'm not keen on having two arbitrarily different idle state binidngs and parsers. Thanks, Mark.
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index a1f2aff..62ffabd 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1253,6 +1253,82 @@ out: } EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain); +static int genpd_of_get_power_state(struct genpd_power_state *genpd_state, + struct device_node *state_node) +{ + int err = 0; + u32 latency; + u32 residency; + u32 param; + u32 entry_latency, exit_latency; + + err = of_property_read_u32(state_node, "entry-latency-us", + &entry_latency); + if (err) { + pr_debug(" * %s missing entry-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + + err = of_property_read_u32(state_node, "exit-latency-us", + &exit_latency); + if (err) { + pr_debug(" * %s missing exit-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + + err = of_property_read_u32(state_node, "residency-us", &residency); + if (!err) + genpd_state->residency_ns = 1000 * residency; + + err = of_property_read_u32(state_node, "state-param", ¶m); + if (!err) + genpd_state->param = param; + + latency = entry_latency + exit_latency; + genpd_state->power_on_latency_ns = 1000 * latency; + genpd_state->power_off_latency_ns = 1000 * entry_latency; + + return 0; +} + +static int genpd_of_parse_power_states(struct generic_pm_domain *genpd) +{ + struct device_node *np; + int i, err = 0; + + for (i = 0; i < GENPD_MAX_NUM_STATES; i++) { + np = of_parse_phandle(genpd->of_node, "power-states", i); + if (!np) + break; + + err = genpd_of_get_power_state(&genpd->states[i], np); + if (err) { + pr_err + ("Parsing idle state node %s failed with err %d\n", + np->full_name, err); + err = -EINVAL; + break; + } + of_node_put(np); + } + + if (err) + return err; + + genpd->state_count = i; + return 0; +} + +static int genpd_of_parse(struct generic_pm_domain *genpd) +{ + if (!genpd->of_node) + return 0; + + return genpd_of_parse_power_states(genpd); +} + /** * pm_genpd_init - Initialize a generic I/O PM domain object. * @genpd: PM domain object to initialize. @@ -1262,8 +1338,10 @@ EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain); * Returns 0 on successful initialization, else a negative error code. */ int pm_genpd_init(struct generic_pm_domain *genpd, - struct dev_power_governor *gov, bool is_off) + struct dev_power_governor *gov, bool is_off) { + int ret; + if (IS_ERR_OR_NULL(genpd)) return -EINVAL; @@ -1306,6 +1384,10 @@ int pm_genpd_init(struct generic_pm_domain *genpd, genpd->dev_ops.start = pm_clk_resume; } + ret = genpd_of_parse(genpd); + if (ret) + return ret; + if (genpd->state_idx >= GENPD_MAX_NUM_STATES) { pr_warn("Initial state index out of bounds.\n"); genpd->state_idx = GENPD_MAX_NUM_STATES - 1; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 31fec85..a3ac52d 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -40,6 +40,8 @@ struct gpd_dev_ops { struct genpd_power_state { s64 power_off_latency_ns; s64 power_on_latency_ns; + s64 residency_ns; + u32 param; }; struct generic_pm_domain { @@ -51,6 +53,7 @@ struct generic_pm_domain { struct mutex lock; struct dev_power_governor *gov; struct work_struct power_off_work; + struct device_node *of_node; /* Device node of the PM domain */ const char *name; atomic_t sd_count; /* Number of subdomains with power "on" */ enum gpd_status status; /* Current state of the domain */