Message ID | 20191230144402.30195-1-ulf.hansson@linaro.org |
---|---|
Headers | show |
Series | cpuidle: psci: Support hierarchical CPU arrangement | expand |
On Mon, 30 Dec 2019 at 17:35, Sudeep Holla <sudeep.holla@arm.com> wrote: > > On Mon, Dec 30, 2019 at 03:43:57PM +0100, Ulf Hansson wrote: > > The per CPU variable psci_power_state, contains an array of fixed values, > > which reflects the corresponding arm,psci-suspend-param parsed from DT, for > > each of the available CPU idle states. > > > > This isn't sufficient when using the hierarchical CPU topology in DT, in > > combination with having PSCI OS initiated (OSI) mode enabled. More > > precisely, in OSI mode, Linux is responsible of telling the PSCI FW what > > idle state the cluster (a group of CPUs) should enter, while in PSCI > > Platform Coordinated (PC) mode, each CPU independently votes for an idle > > state of the cluster. > > > > For this reason, introduce a per CPU variable called domain_state and > > implement two helper functions to read/write its value. Then let the > > domain_state take precedence over the regular selected state, when entering > > and idle state. > > > > To avoid executing the above OSI specific code in the ->enter() callback, > > while operating in the default PSCI Platform Coordinated mode, let's also > > add a new enter-function and use it for OSI. > > > > Co-developed-by: Lina Iyer <lina.iyer@linaro.org> > > Signed-off-by: Lina Iyer <lina.iyer@linaro.org> > > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> > > --- > > > > Changes in v5: > > - None. > > > > --- > > drivers/cpuidle/cpuidle-psci.c | 56 ++++++++++++++++++++++++++++++---- > > 1 file changed, 50 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c > > index 6a87848be3c3..9600fe674a89 100644 > > --- a/drivers/cpuidle/cpuidle-psci.c > > +++ b/drivers/cpuidle/cpuidle-psci.c > > @@ -29,14 +29,47 @@ struct psci_cpuidle_data { > > }; > > > > static DEFINE_PER_CPU_READ_MOSTLY(struct psci_cpuidle_data, psci_cpuidle_data); > > +static DEFINE_PER_CPU(u32, domain_state); > > + > > +static inline void psci_set_domain_state(u32 state) > > +{ > > + __this_cpu_write(domain_state, state); > > +} > > + > > +static inline u32 psci_get_domain_state(void) > > +{ > > + return __this_cpu_read(domain_state); > > +} > > + > > +static inline int psci_enter_state(int idx, u32 state) > > +{ > > + return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, idx, state); > > +} > > + > > +static int psci_enter_domain_idle_state(struct cpuidle_device *dev, > > + struct cpuidle_driver *drv, int idx) > > +{ > > + struct psci_cpuidle_data *data = this_cpu_ptr(&psci_cpuidle_data); > > + u32 *states = data->psci_states; > > + u32 state = psci_get_domain_state(); > > + int ret; > > + > > + if (!state) > > + state = states[idx]; > > + > > + ret = psci_enter_state(idx, state); > > + > > + /* Clear the domain state to start fresh when back from idle. */ > > + psci_set_domain_state(0); > > + return ret; > > +} > > > > static int psci_enter_idle_state(struct cpuidle_device *dev, > > struct cpuidle_driver *drv, int idx) > > { > > u32 *state = __this_cpu_read(psci_cpuidle_data.psci_states); > > > > - return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, > > - idx, state[idx]); > > + return psci_enter_state(idx, state[idx]); > > } > > > > static struct cpuidle_driver psci_idle_driver __initdata = { > > @@ -79,7 +112,8 @@ static int __init psci_dt_parse_state_node(struct device_node *np, u32 *state) > > return 0; > > } > > > > -static int __init psci_dt_cpu_init_idle(struct device_node *cpu_node, > > +static int __init psci_dt_cpu_init_idle(struct cpuidle_driver *drv, > > + struct device_node *cpu_node, > > unsigned int state_count, int cpu) > > { > > int i, ret = 0; > > @@ -118,6 +152,15 @@ static int __init psci_dt_cpu_init_idle(struct device_node *cpu_node, > > ret = PTR_ERR(data->dev); > > goto free_mem; > > } > > + > > + /* > > + * Using the deepest state for the CPU to trigger a potential > > + * selection of a shared state for the domain, assumes the > > + * domain states are all deeper states. > > + */ > > + if (data->dev) > > Do we still need this check ? I thought we won't attach genpd if OSI is > not enabled. If possible, please drop the check. This check is still needed. psci_dt_attach_cpu() now returns NULL when OSI has not been enabled (see patch 14), as we agreed on during the discussions around the previous version. > > Other than that, looks good to me. > > Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Thanks! Kind regards Uffe
Rafael, On Mon, 30 Dec 2019 at 15:44, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > Changes in v5: > - Remove PM domains in the error path, when failing to enable OSI. > - Folded in a patch that adds a genpd OF helper to remove subdomains. > - Added reviewed-by tags. > > Changes in v4: > - Move the check for OSI support from psci_dt_attach_cpu() to the > caller's side of it. > - Add comment in the code about using the deepest idle state as the > triggering point for the domain state selection. > - Folded in a patch to enable support for CPU hotplug. > > Changes in v3: > - Take one step further to completely avoid executing any OSI specific > code from the ->enter() callback, while operating in the default PSCI > Platform Coordinated mode. > - Update example for the PSCI DT bindings to make it compile with > "make dt_binding_check" > > Changes in v2: > - Avoid to affect the non-OSI path with specific changes for OSI. This > forced me to re-order the series and a caused more or less minor changes > to most of the patches. > - Updated the DT bindings for PSCI to clarify and to include the "psci" > name of the PM domain to attach to. > - Replaced patch1 with another patch from Sudeep, solving the same > problem, but in a different way. > > This series enables initial support for hierarchical CPU arrangement, managed > by PSCI and its corresponding cpuidle driver. It's based on using the generic > PM domain (genpd), which nowadays also supports devices belonging to CPUs. > > The last DTS patch enables the hierarchical topology to be used for the Qcom > 410c Dragonboard, which supports the PSCI OS-initiated mode. > > More detailed background can be found from previous submissions [1]. > > The series is also available at: > git.linaro.org/people/ulf.hansson/linux-pm.git next > > Kind regards > Ulf Hansson > > [1] > https://lwn.net/Articles/788306/ > > Lina Iyer (1): > cpuidle: dt: Support hierarchical CPU idle states > > Sudeep Holla (1): > cpuidle: psci: Align psci_power_state count with idle state count > > Ulf Hansson (13): > dt: psci: Update DT bindings to support hierarchical PSCI states > firmware: psci: Export functions to manage the OSI mode > of: base: Add of_get_cpu_state_node() to get idle states for a CPU > node > cpuidle: psci: Simplify OF parsing of CPU idle state nodes > cpuidle: psci: Support hierarchical CPU idle states > cpuidle: psci: Add a helper to attach a CPU to its PM domain > cpuidle: psci: Attach CPU devices to their PM domains > cpuidle: psci: Prepare to use OS initiated suspend mode via PM domains > cpuidle: psci: Manage runtime PM in the idle path > cpuidle: psci: Support CPU hotplug for the hierarchical model > PM / Domains: Introduce a genpd OF helper that removes a subdomain > cpuidle: psci: Add support for PM domains by using genpd > arm64: dts: Convert to the hierarchical CPU topology layout for > MSM8916 > > .../devicetree/bindings/arm/cpus.yaml | 15 + > .../devicetree/bindings/arm/psci.yaml | 104 ++++++ > arch/arm64/boot/dts/qcom/msm8916.dtsi | 57 +++- > drivers/base/power/domain.c | 38 +++ > drivers/cpuidle/Makefile | 4 +- > drivers/cpuidle/cpuidle-psci-domain.c | 308 ++++++++++++++++++ > drivers/cpuidle/cpuidle-psci.c | 161 +++++++-- > drivers/cpuidle/cpuidle-psci.h | 17 + > drivers/cpuidle/dt_idle_states.c | 5 +- > drivers/firmware/psci/psci.c | 18 +- > drivers/of/base.c | 36 ++ > include/linux/cpuhotplug.h | 1 + > include/linux/of.h | 8 + > include/linux/pm_domain.h | 8 + > include/linux/psci.h | 2 + > 15 files changed, 747 insertions(+), 35 deletions(-) > create mode 100644 drivers/cpuidle/cpuidle-psci-domain.c > create mode 100644 drivers/cpuidle/cpuidle-psci.h > > -- > 2.17.1 > This series is ready to go (unless you have some objections of course), would you mind queuing it up? Of course, patch15 can be left for arm-soc. If you prefer a pull-request, just tell me. Kind regards Uffe
On Tue, 31 Dec 2019 at 11:43, Rafael J. Wysocki <rafael@kernel.org> wrote: > > On Tue, Dec 31, 2019 at 11:38 AM Ulf Hansson <ulf.hansson@linaro.org> wrote: > > > > Rafael, > > > > On Mon, 30 Dec 2019 at 15:44, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > > > > > Changes in v5: > > > - Remove PM domains in the error path, when failing to enable OSI. > > > - Folded in a patch that adds a genpd OF helper to remove subdomains. > > > - Added reviewed-by tags. > > > > > > Changes in v4: > > > - Move the check for OSI support from psci_dt_attach_cpu() to the > > > caller's side of it. > > > - Add comment in the code about using the deepest idle state as the > > > triggering point for the domain state selection. > > > - Folded in a patch to enable support for CPU hotplug. > > > > > > Changes in v3: > > > - Take one step further to completely avoid executing any OSI specific > > > code from the ->enter() callback, while operating in the default PSCI > > > Platform Coordinated mode. > > > - Update example for the PSCI DT bindings to make it compile with > > > "make dt_binding_check" > > > > > > Changes in v2: > > > - Avoid to affect the non-OSI path with specific changes for OSI. This > > > forced me to re-order the series and a caused more or less minor changes > > > to most of the patches. > > > - Updated the DT bindings for PSCI to clarify and to include the "psci" > > > name of the PM domain to attach to. > > > - Replaced patch1 with another patch from Sudeep, solving the same > > > problem, but in a different way. > > > > > > This series enables initial support for hierarchical CPU arrangement, managed > > > by PSCI and its corresponding cpuidle driver. It's based on using the generic > > > PM domain (genpd), which nowadays also supports devices belonging to CPUs. > > > > > > The last DTS patch enables the hierarchical topology to be used for the Qcom > > > 410c Dragonboard, which supports the PSCI OS-initiated mode. > > > > > > More detailed background can be found from previous submissions [1]. > > > > > > The series is also available at: > > > git.linaro.org/people/ulf.hansson/linux-pm.git next > > > > > > Kind regards > > > Ulf Hansson > > > > > > [1] > > > https://lwn.net/Articles/788306/ > > > > > > Lina Iyer (1): > > > cpuidle: dt: Support hierarchical CPU idle states > > > > > > Sudeep Holla (1): > > > cpuidle: psci: Align psci_power_state count with idle state count > > > > > > Ulf Hansson (13): > > > dt: psci: Update DT bindings to support hierarchical PSCI states > > > firmware: psci: Export functions to manage the OSI mode > > > of: base: Add of_get_cpu_state_node() to get idle states for a CPU > > > node > > > cpuidle: psci: Simplify OF parsing of CPU idle state nodes > > > cpuidle: psci: Support hierarchical CPU idle states > > > cpuidle: psci: Add a helper to attach a CPU to its PM domain > > > cpuidle: psci: Attach CPU devices to their PM domains > > > cpuidle: psci: Prepare to use OS initiated suspend mode via PM domains > > > cpuidle: psci: Manage runtime PM in the idle path > > > cpuidle: psci: Support CPU hotplug for the hierarchical model > > > PM / Domains: Introduce a genpd OF helper that removes a subdomain > > > cpuidle: psci: Add support for PM domains by using genpd > > > arm64: dts: Convert to the hierarchical CPU topology layout for > > > MSM8916 > > > > > > .../devicetree/bindings/arm/cpus.yaml | 15 + > > > .../devicetree/bindings/arm/psci.yaml | 104 ++++++ > > > arch/arm64/boot/dts/qcom/msm8916.dtsi | 57 +++- > > > drivers/base/power/domain.c | 38 +++ > > > drivers/cpuidle/Makefile | 4 +- > > > drivers/cpuidle/cpuidle-psci-domain.c | 308 ++++++++++++++++++ > > > drivers/cpuidle/cpuidle-psci.c | 161 +++++++-- > > > drivers/cpuidle/cpuidle-psci.h | 17 + > > > drivers/cpuidle/dt_idle_states.c | 5 +- > > > drivers/firmware/psci/psci.c | 18 +- > > > drivers/of/base.c | 36 ++ > > > include/linux/cpuhotplug.h | 1 + > > > include/linux/of.h | 8 + > > > include/linux/pm_domain.h | 8 + > > > include/linux/psci.h | 2 + > > > 15 files changed, 747 insertions(+), 35 deletions(-) > > > create mode 100644 drivers/cpuidle/cpuidle-psci-domain.c > > > create mode 100644 drivers/cpuidle/cpuidle-psci.h > > > > > > -- > > > 2.17.1 > > > > > > > This series is ready to go (unless you have some objections of > > course), would you mind queuing it up? > > > > Of course, patch15 can be left for arm-soc. > > > > If you prefer a pull-request, just tell me. > > So I would prefer arm-soc to take the whole lot if that's not a problem. Not really, I can send a PR to those guys within a day or two. Although, I assume you are aware that most of the changes are in drivers/cpuidle/ ...? > > Feel free to add ACKs from me to the patches for this purpose if that helps > > Thanks! Thanks! Kind regards Uffe