* [PATCH v10 06/27] of: base: Add of_get_cpu_state_node() to get idle states for a CPU node [not found] <20181129174700.16585-1-ulf.hansson@linaro.org> @ 2018-11-29 17:46 ` Ulf Hansson 2018-12-19 11:05 ` Daniel Lezcano 0 siblings, 1 reply; 2+ messages in thread From: Ulf Hansson @ 2018-11-29 17:46 UTC (permalink / raw) To: Rafael J . Wysocki, Sudeep Holla, Lorenzo Pieralisi, Mark Rutland, Daniel Lezcano, linux-pm Cc: devicetree, Ulf Hansson, Vincent Guittot, Geert Uytterhoeven, Kevin Hilman, Stephen Boyd, Viresh Kumar, linux-kernel, Lina Iyer, Tony Lindgren, Rob Herring, linux-arm-msm, Raju P . L . S . S . S . N, linux-arm-kernel The CPU's idle state nodes are currently parsed at the common cpuidle DT library, but also when initializing back-end data for the arch specific CPU operations, as in the PSCI driver case. To avoid open-coding, let's introduce of_get_cpu_state_node(), which takes the device node for the CPU and the index to the requested idle state node, as in-parameters. In case a corresponding idle state node is found, it returns the node with the refcount incremented for it, else it returns NULL. Moreover, for ARM, there are two generic methods, to describe the CPU's idle states, either via the flattened description through the "cpu-idle-states" binding [1] or via the hierarchical layout, using the "power-domains" and the "domain-idle-states" bindings [2]. Hence, let's take both options into account. [1] Documentation/devicetree/bindings/arm/idle-states.txt [2] Documentation/devicetree/bindings/arm/psci.txt Cc: Rob Herring <robh+dt@kernel.org> Cc: devicetree@vger.kernel.org Cc: Lina Iyer <ilina@codeaurora.org> Suggested-by: Sudeep Holla <sudeep.holla@arm.com> Co-developed-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Rob Herring <robh@kernel.org> --- Changes in v10: - None. --- drivers/of/base.c | 35 +++++++++++++++++++++++++++++++++++ include/linux/of.h | 8 ++++++++ 2 files changed, 43 insertions(+) diff --git a/drivers/of/base.c b/drivers/of/base.c index 09692c9b32a7..8f6974a22006 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -429,6 +429,41 @@ int of_cpu_node_to_id(struct device_node *cpu_node) } EXPORT_SYMBOL(of_cpu_node_to_id); +/** + * of_get_cpu_state_node - Get CPU's idle state node at the given index + * + * @cpu_node: The device node for the CPU + * @index: The index in the list of the idle states + * + * Two generic methods can be used to describe a CPU's idle states, either via + * a flattened description through the "cpu-idle-states" binding or via the + * hierarchical layout, using the "power-domains" and the "domain-idle-states" + * bindings. This function check for both and returns the idle state node for + * the requested index. + * + * In case and idle state node is found at index, the refcount incremented for + * it, so call of_node_put() on it when done. Returns NULL if not found. + */ +struct device_node *of_get_cpu_state_node(struct device_node *cpu_node, + int index) +{ + struct of_phandle_args args; + int err; + + err = of_parse_phandle_with_args(cpu_node, "power-domains", + "#power-domain-cells", 0, &args); + if (!err) { + struct device_node *state_node = + of_parse_phandle(args.np, "domain-idle-states", index); + + of_node_put(args.np); + return state_node; + } + + return of_parse_phandle(cpu_node, "cpu-idle-states", index); +} +EXPORT_SYMBOL(of_get_cpu_state_node); + /** * __of_device_is_compatible() - Check if the node matches given constraints * @device: pointer to node diff --git a/include/linux/of.h b/include/linux/of.h index a5aee3c438ad..f9f0c65c095c 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -348,6 +348,8 @@ extern const void *of_get_property(const struct device_node *node, int *lenp); extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread); extern struct device_node *of_get_next_cpu_node(struct device_node *prev); +extern struct device_node *of_get_cpu_state_node(struct device_node *cpu_node, + int index); #define for_each_property_of_node(dn, pp) \ for (pp = dn->properties; pp != NULL; pp = pp->next) @@ -762,6 +764,12 @@ static inline struct device_node *of_get_next_cpu_node(struct device_node *prev) return NULL; } +static inline struct device_node *of_get_cpu_state_node(struct device_node *cpu_node, + int index) +{ + return NULL; +} + static inline int of_n_addr_cells(struct device_node *np) { return 0; -- 2.17.1 ^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH v10 06/27] of: base: Add of_get_cpu_state_node() to get idle states for a CPU node 2018-11-29 17:46 ` [PATCH v10 06/27] of: base: Add of_get_cpu_state_node() to get idle states for a CPU node Ulf Hansson @ 2018-12-19 11:05 ` Daniel Lezcano 0 siblings, 0 replies; 2+ messages in thread From: Daniel Lezcano @ 2018-12-19 11:05 UTC (permalink / raw) To: Ulf Hansson, Rafael J . Wysocki, Sudeep Holla, Lorenzo Pieralisi, Mark Rutland, linux-pm Cc: Raju P . L . S . S . S . N, Stephen Boyd, Tony Lindgren, Kevin Hilman, Lina Iyer, Viresh Kumar, Vincent Guittot, Geert Uytterhoeven, linux-arm-kernel, linux-arm-msm, linux-kernel, Rob Herring, devicetree On 29/11/2018 18:46, Ulf Hansson wrote: > The CPU's idle state nodes are currently parsed at the common cpuidle DT > library, but also when initializing back-end data for the arch specific CPU > operations, as in the PSCI driver case. > > To avoid open-coding, let's introduce of_get_cpu_state_node(), which takes > the device node for the CPU and the index to the requested idle state node, > as in-parameters. In case a corresponding idle state node is found, it > returns the node with the refcount incremented for it, else it returns > NULL. > > Moreover, for ARM, there are two generic methods, to describe the CPU's > idle states, either via the flattened description through the > "cpu-idle-states" binding [1] or via the hierarchical layout, using the > "power-domains" and the "domain-idle-states" bindings [2]. Hence, let's > take both options into account. > > [1] > Documentation/devicetree/bindings/arm/idle-states.txt > [2] > Documentation/devicetree/bindings/arm/psci.txt > > Cc: Rob Herring <robh+dt@kernel.org> > Cc: devicetree@vger.kernel.org > Cc: Lina Iyer <ilina@codeaurora.org> > Suggested-by: Sudeep Holla <sudeep.holla@arm.com> > Co-developed-by: Lina Iyer <lina.iyer@linaro.org> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> > Reviewed-by: Rob Herring <robh@kernel.org> Nitpicking some kerneldoc formatting below. Other than that: Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org> > --- > > Changes in v10: > - None. > > --- > drivers/of/base.c | 35 +++++++++++++++++++++++++++++++++++ > include/linux/of.h | 8 ++++++++ > 2 files changed, 43 insertions(+) > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 09692c9b32a7..8f6974a22006 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -429,6 +429,41 @@ int of_cpu_node_to_id(struct device_node *cpu_node) > } > EXPORT_SYMBOL(of_cpu_node_to_id); > > +/** > + * of_get_cpu_state_node - Get CPU's idle state node at the given index > + * > + * @cpu_node: The device node for the CPU > + * @index: The index in the list of the idle states > + * > + * Two generic methods can be used to describe a CPU's idle states, either via > + * a flattened description through the "cpu-idle-states" binding or via the > + * hierarchical layout, using the "power-domains" and the "domain-idle-states" > + * bindings. This function check for both and returns the idle state node for > + * the requested index. > + * > + * In case and idle state node is found at index, the refcount incremented for s/and/an/ s/index/@index/ > + * it, so call of_node_put() on it when done. Returns NULL if not found. The Return description must be in a separate section. > + */ > +struct device_node *of_get_cpu_state_node(struct device_node *cpu_node, > + int index) > +{ > + struct of_phandle_args args; > + int err; > + > + err = of_parse_phandle_with_args(cpu_node, "power-domains", > + "#power-domain-cells", 0, &args); > + if (!err) { > + struct device_node *state_node = > + of_parse_phandle(args.np, "domain-idle-states", index); > + > + of_node_put(args.np); > + return state_node; > + } > + > + return of_parse_phandle(cpu_node, "cpu-idle-states", index); > +} > +EXPORT_SYMBOL(of_get_cpu_state_node); > + > /** > * __of_device_is_compatible() - Check if the node matches given constraints > * @device: pointer to node > diff --git a/include/linux/of.h b/include/linux/of.h > index a5aee3c438ad..f9f0c65c095c 100644 > --- a/include/linux/of.h > +++ b/include/linux/of.h > @@ -348,6 +348,8 @@ extern const void *of_get_property(const struct device_node *node, > int *lenp); > extern struct device_node *of_get_cpu_node(int cpu, unsigned int *thread); > extern struct device_node *of_get_next_cpu_node(struct device_node *prev); > +extern struct device_node *of_get_cpu_state_node(struct device_node *cpu_node, > + int index); > > #define for_each_property_of_node(dn, pp) \ > for (pp = dn->properties; pp != NULL; pp = pp->next) > @@ -762,6 +764,12 @@ static inline struct device_node *of_get_next_cpu_node(struct device_node *prev) > return NULL; > } > > +static inline struct device_node *of_get_cpu_state_node(struct device_node *cpu_node, > + int index) > +{ > + return NULL; > +} > + > static inline int of_n_addr_cells(struct device_node *np) > { > return 0; > -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog ^ permalink raw reply [flat|nested] 2+ messages in thread
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2018-11-29 17:46 ` [PATCH v10 06/27] of: base: Add of_get_cpu_state_node() to get idle states for a CPU node Ulf Hansson
2018-12-19 11:05 ` Daniel Lezcano
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