| Message ID | 1501168218-26741-3-git-send-email-suzuki.poulose@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Please use get_maintainers and cc the right people/lists. +Frank, DT list On Thu, Jul 27, 2017 at 10:10 AM, Suzuki K Poulose <suzuki.poulose@arm.com> wrote: > Add a helper to map a device node to a logical CPU number to avoid > duplication. Currently this is open coded in different places (e.g > gic-v3, coresight). The helper tries to map device node to a "possible" > logical CPU id, which may not be online yet. It is the responsibility > of the user to make sure that the CPU is online. The helper uses > of_get_cpu_node() which uses arch specific backends to match the phyiscal > ids. > > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Sudeep Holla <sudeep.holla@arm.com> > Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > --- > drivers/of/base.c | 26 ++++++++++++++++++++++++++ > include/linux/of_device.h | 7 +++++++ > 2 files changed, 33 insertions(+) > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 686628d..0b01515 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -420,6 +420,32 @@ struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) > EXPORT_SYMBOL(of_get_cpu_node); > > /** > + * of_device_node_get_cpu: Get the logical CPU number for a given device_node > + * > + * @cpu_node: Pointer to the device_node for CPU. > + * > + * Returns the logical CPU number of the given CPU device_node. > + * Returns >= nr_cpu_ids if CPU is not found. Wouldn't negative be easier to test for? Then the caller doesn't need to know nr_cpu_ids. > + */ > +int of_device_node_get_cpu(struct device_node *cpu_node) of_device_* is for functions operating on struct device. So find another name. of_cpu_node_to_id perhaps. _get functions generally imply incrementing ref counts which you are not doing here. > +{ > + int cpu; > + bool found = false; > + struct device_node *np; > + > + for_each_possible_cpu(cpu) { > + np = of_get_cpu_node(cpu, NULL); > + found = (cpu_node == np); > + of_node_put(np); > + if (found) > + break; > + } > + > + return cpu; > +} > +EXPORT_SYMBOL(of_device_node_get_cpu); > + > +/** > * __of_device_is_compatible() - Check if the node matches given constraints > * @device: pointer to node > * @compat: required compatible string, NULL or "" for any match > diff --git a/include/linux/of_device.h b/include/linux/of_device.h > index b4ad8b4..00a4ba9 100644 > --- a/include/linux/of_device.h > +++ b/include/linux/of_device.h > @@ -40,6 +40,8 @@ extern int of_device_request_module(struct device *dev); > extern void of_device_uevent(struct device *dev, struct kobj_uevent_env *env); > extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env); > > +extern int of_device_node_get_cpu(struct device_node *np); > + Wrong place for this. > static inline void of_device_node_put(struct device *dev) > { > of_node_put(dev->of_node); > @@ -110,6 +112,11 @@ static inline int of_dma_configure(struct device *dev, struct device_node *np) > } > static inline void of_dma_deconfigure(struct device *dev) > {} > + > +static inline int of_device_node_get_cpu(struct device_node *np) > +{ > + return nr_cpu_ids; > +} > #endif /* CONFIG_OF */ > > #endif /* _LINUX_OF_DEVICE_H */ > -- > 2.7.5 >
On 27/07/17 16:48, Rob Herring wrote: > Please use get_maintainers and cc the right people/lists. > Sorry about that, will fix it. > +Frank, DT list > > On Thu, Jul 27, 2017 at 10:10 AM, Suzuki K Poulose > <suzuki.poulose@arm.com> wrote: >> Add a helper to map a device node to a logical CPU number to avoid >> duplication. Currently this is open coded in different places (e.g >> gic-v3, coresight). The helper tries to map device node to a "possible" >> logical CPU id, which may not be online yet. It is the responsibility >> of the user to make sure that the CPU is online. The helper uses >> of_get_cpu_node() which uses arch specific backends to match the phyiscal >> ids. >> >> Cc: Rob Herring <robh+dt@kernel.org> >> Cc: Mark Rutland <mark.rutland@arm.com> >> Cc: Sudeep Holla <sudeep.holla@arm.com> >> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> >> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> >> --- >> drivers/of/base.c | 26 ++++++++++++++++++++++++++ >> include/linux/of_device.h | 7 +++++++ >> 2 files changed, 33 insertions(+) >> >> diff --git a/drivers/of/base.c b/drivers/of/base.c >> index 686628d..0b01515 100644 >> --- a/drivers/of/base.c >> +++ b/drivers/of/base.c >> @@ -420,6 +420,32 @@ struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) >> EXPORT_SYMBOL(of_get_cpu_node); >> >> /** >> + * of_device_node_get_cpu: Get the logical CPU number for a given device_node >> + * >> + * @cpu_node: Pointer to the device_node for CPU. >> + * >> + * Returns the logical CPU number of the given CPU device_node. >> + * Returns >= nr_cpu_ids if CPU is not found. > > Wouldn't negative be easier to test for? Then the caller doesn't need > to know nr_cpu_ids. I followed the conventions used by cpu_mask upon error here. But, we could return -ENODEV upon failure here. > >> + */ >> +int of_device_node_get_cpu(struct device_node *cpu_node) > > of_device_* is for functions operating on struct device. So find > another name. of_cpu_node_to_id perhaps. > > _get functions generally imply incrementing ref counts which you are > not doing here. > OK, I can switch to of_cpu_node_to_id(). >> +{ >> + int cpu; >> + bool found = false; >> + struct device_node *np; >> + >> + for_each_possible_cpu(cpu) { >> + np = of_get_cpu_node(cpu, NULL); >> + found = (cpu_node == np); >> + of_node_put(np); >> + if (found) >> + break; >> + } >> + >> + return cpu; >> +} >> +EXPORT_SYMBOL(of_device_node_get_cpu); >> + >> +/** >> * __of_device_is_compatible() - Check if the node matches given constraints >> * @device: pointer to node >> * @compat: required compatible string, NULL or "" for any match >> diff --git a/include/linux/of_device.h b/include/linux/of_device.h >> index b4ad8b4..00a4ba9 100644 >> --- a/include/linux/of_device.h >> +++ b/include/linux/of_device.h >> @@ -40,6 +40,8 @@ extern int of_device_request_module(struct device *dev); >> extern void of_device_uevent(struct device *dev, struct kobj_uevent_env *env); >> extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env); >> >> +extern int of_device_node_get_cpu(struct device_node *np); >> + > > Wrong place for this. > How about include/linux/of.h ? Suzuki
diff --git a/drivers/of/base.c b/drivers/of/base.c index 686628d..0b01515 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -420,6 +420,32 @@ struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) EXPORT_SYMBOL(of_get_cpu_node); /** + * of_device_node_get_cpu: Get the logical CPU number for a given device_node + * + * @cpu_node: Pointer to the device_node for CPU. + * + * Returns the logical CPU number of the given CPU device_node. + * Returns >= nr_cpu_ids if CPU is not found. + */ +int of_device_node_get_cpu(struct device_node *cpu_node) +{ + int cpu; + bool found = false; + struct device_node *np; + + for_each_possible_cpu(cpu) { + np = of_get_cpu_node(cpu, NULL); + found = (cpu_node == np); + of_node_put(np); + if (found) + break; + } + + return cpu; +} +EXPORT_SYMBOL(of_device_node_get_cpu); + +/** * __of_device_is_compatible() - Check if the node matches given constraints * @device: pointer to node * @compat: required compatible string, NULL or "" for any match diff --git a/include/linux/of_device.h b/include/linux/of_device.h index b4ad8b4..00a4ba9 100644 --- a/include/linux/of_device.h +++ b/include/linux/of_device.h @@ -40,6 +40,8 @@ extern int of_device_request_module(struct device *dev); extern void of_device_uevent(struct device *dev, struct kobj_uevent_env *env); extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env); +extern int of_device_node_get_cpu(struct device_node *np); + static inline void of_device_node_put(struct device *dev) { of_node_put(dev->of_node); @@ -110,6 +112,11 @@ static inline int of_dma_configure(struct device *dev, struct device_node *np) } static inline void of_dma_deconfigure(struct device *dev) {} + +static inline int of_device_node_get_cpu(struct device_node *np) +{ + return nr_cpu_ids; +} #endif /* CONFIG_OF */ #endif /* _LINUX_OF_DEVICE_H */