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2019-03-12PM / OPP: Update performance state when freq == old_freqViresh Kumar1-1/+1
At boot up, CPUFreq core performs a sanity check to see if the system is running at a frequency defined in the frequency table of the CPU. If so, we try to find a valid frequency (lowest frequency greater than the currently programmed frequency) from the table and set it. When the call reaches dev_pm_opp_set_rate(), it calls _find_freq_ceil(opp_table, &old_freq) to find the previously configured OPP and this call also updates the old_freq. This eventually sets the old_freq == freq (new target requested by cpufreq core) and we skip updating the performance state in this case. Fix this by also updating the performance state when the old_freq == freq. Fixes: ca1b5d77b1c6 ("OPP: Configure all required OPPs") Cc: v5.0 <stable@vger.kernel.org> # v5.0 Reported-by: Niklas Cassel <niklas.cassel@linaro.org> Tested-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-03-11OPP: Fix handling of multiple power domainsRajendra Nayak1-2/+14
We seem to rely on the number of phandles specified in the 'required-opps' property to identify cases where a device is associated with multiple power domains and hence would have multiple virtual devices that have to be dealt with. In cases where we do have devices with multiple power domains but with only one of them being scalable, this logic seems to fail. Instead read the number of power domains from DT to identify such cases. Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-03-06Merge tag 'pm-5.1-rc1' of ↵Linus Torvalds4-104/+142
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These are PM-runtime framework changes to use ktime instead of jiffies for accounting, new PM core flag to mark devices that don't need any form of power management, cpuidle updates including driver API documentation and a new governor, cpufreq updates including a new driver for Armada 8K, thermal cleanups and more, some energy-aware scheduling (EAS) enabling changes, new chips support in the intel_idle and RAPL drivers and assorted cleanups in some other places. Specifics: - Update the PM-runtime framework to use ktime instead of jiffies for accounting (Thara Gopinath, Vincent Guittot) - Optimize the autosuspend code in the PM-runtime framework somewhat (Ladislav Michl) - Add a PM core flag to mark devices that don't need any form of power management (Sudeep Holla) - Introduce driver API documentation for cpuidle and add a new cpuidle governor for tickless systems (Rafael Wysocki) - Add Jacobsville support to the intel_idle driver (Zhang Rui) - Clean up a cpuidle core header file and the cpuidle-dt and ACPI processor-idle drivers (Yangtao Li, Joseph Lo, Yazen Ghannam) - Add new cpufreq driver for Armada 8K (Gregory Clement) - Fix and clean up cpufreq core (Rafael Wysocki, Viresh Kumar, Amit Kucheria) - Add support for light-weight tear-down and bring-up of CPUs to the cpufreq core and use it in the cpufreq-dt driver (Viresh Kumar) - Fix cpu_cooling Kconfig dependencies, add support for CPU cooling auto-registration to the cpufreq core and use it in multiple cpufreq drivers (Amit Kucheria) - Fix some minor issues and do some cleanups in the davinci, e_powersaver, ap806, s5pv210, qcom and kryo cpufreq drivers (Bartosz Golaszewski, Gustavo Silva, Julia Lawall, Paweł Chmiel, Taniya Das, Viresh Kumar) - Add a Hisilicon CPPC quirk to the cppc_cpufreq driver (Xiongfeng Wang) - Clean up the intel_pstate and acpi-cpufreq drivers (Erwan Velu, Rafael Wysocki) - Clean up multiple cpufreq drivers (Yangtao Li) - Update cpufreq-related MAINTAINERS entries (Baruch Siach, Lukas Bulwahn) - Add support for exposing the Energy Model via debugfs and make multiple cpufreq drivers register an Energy Model to support energy-aware scheduling (Quentin Perret, Dietmar Eggemann, Matthias Kaehlcke) - Add Ice Lake mobile and Jacobsville support to the Intel RAPL power-capping driver (Gayatri Kammela, Zhang Rui) - Add a power estimation helper to the operating performance points (OPP) framework and clean up a core function in it (Quentin Perret, Viresh Kumar) - Make minor improvements in the generic power domains (genpd), OPP and system suspend frameworks and in the PM core (Aditya Pakki, Douglas Anderson, Greg Kroah-Hartman, Rafael Wysocki, Yangtao Li)" * tag 'pm-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (80 commits) cpufreq: kryo: Release OPP tables on module removal cpufreq: ap806: add missing of_node_put after of_device_is_available cpufreq: acpi-cpufreq: Report if CPU doesn't support boost technologies cpufreq: Pass updated policy to driver ->setpolicy() callback cpufreq: Fix two debug messages in cpufreq_set_policy() cpufreq: Reorder and simplify cpufreq_update_policy() cpufreq: Add kerneldoc comments for two core functions PM / core: Add support to skip power management in device/driver model cpufreq: intel_pstate: Rework iowait boosting to be less aggressive cpufreq: intel_pstate: Eliminate intel_pstate_get_base_pstate() cpufreq: intel_pstate: Avoid redundant initialization of local vars powercap/intel_rapl: add Ice Lake mobile ACPI / processor: Set P_LVL{2,3} idle state descriptions cpufreq / cppc: Work around for Hisilicon CPPC cpufreq ACPI / CPPC: Add a helper to get desired performance cpufreq: davinci: move configuration to include/linux/platform_data cpufreq: speedstep: convert BUG() to BUG_ON() cpufreq: powernv: fix missing check of return value in init_powernv_pstates() cpufreq: longhaul: remove unneeded semicolon cpufreq: pcc-cpufreq: remove unneeded semicolon ..
2019-02-15Merge tag 'qcom-drivers-for-5.1' of ↵Arnd Bergmann3-0/+22
git://git.kernel.org/pub/scm/linux/kernel/git/agross/linux into arm/drivers Qualcomm ARM Based Driver Updates for v5.1 * Add Qualcomm RPMh power domain driver and related changes * Fix issues with sleep/wake sets and batch API in RPMh * Update MAINTAINERS Qualcomm entry * Fixup RMTFS-mem sysfs and uevents * Fix error handling in GSBI * Add SMD-RPM compatible entry for SDM660 * tag 'qcom-drivers-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/agross/linux: soc: qcom: smd-rpm: Add sdm660 compatible soc: qcom: gsbi: Fix error handling in gsbi_probe() soc: qcom: rpmh: Avoid accessing freed memory from batch API drivers: qcom: rpmh: avoid sending sleep/wake sets immediately soc: qcom: rmtfs-mem: Make sysfs attributes world-readable soc: qcom: rmtfs-mem: Add class to enable uevents soc: qcom: update config dependencies for QCOM_RPMPD soc: qcom: rpmpd: Drop family A RPM dependency MAINTAINERS: update list of qcom drivers soc: qcom: rpmhpd: Mark mx as a parent for cx soc: qcom: rpmhpd: Add RPMh power domain driver soc: qcom: rpmpd: Add support for get/set performance state soc: qcom: rpmpd: Add a Power domain driver to model corners dt-bindings: power: Add qcom rpm power domain driver bindings OPP: Add support for parsing the 'opp-level' property dt-bindings: opp: Introduce opp-level bindings Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-02-12Merge branch 'opp/linux-next' of ↵Rafael J. Wysocki4-104/+142
git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm into pm-opp Pull operating performance points (OPP) framework updates for v5.1 from Viresh Kumar: "This pull request contains following changes: - Introduced new OPP helper for power-estimation and used it in several cpufreq drivers (Quentin Perret, Matthias Kaehlcke, Dietmar Eggemann, and Yangtao Li). - OPP Debugfs cleanup (Greg KH). - OPP core cleanup (Viresh Kumar)." * 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: cpufreq: OMAP: Register an Energy Model cpufreq: imx6q: Register an Energy Model opp: no need to check return value of debugfs_create functions cpufreq: mediatek: Register an Energy Model cpufreq: scmi: Register an Energy Model cpufreq: arm_big_little: Register an Energy Model cpufreq: scpi: Register an Energy Model cpufreq: dt: Register an Energy Model PM / OPP: Introduce a power estimation helper PM / OPP: Remove unused parameter of _generic_set_opp_clk_only()
2019-02-07opp: no need to check return value of debugfs_create functionsGreg Kroah-Hartman3-98/+38
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Cc: Viresh Kumar <vireshk@kernel.org> Cc: Nishanth Menon <nm@ti.com> Cc: Stephen Boyd <sboyd@kernel.org> Cc: linux-pm@vger.kernel.org Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-02-07PM / OPP: Introduce a power estimation helperQuentin Perret1-0/+99
The Energy Model (EM) framework provides an API to let drivers register the active power of CPUs. The drivers are expected to provide a callback method which estimates the power consumed by a CPU at each available performance levels. How exactly this should be implemented, however, depends on the platform. On some systems, PM_OPP knows the voltage and frequency at which CPUs can run. When coupled with the CPU 'capacitance' (as provided by the 'dynamic-power-coefficient' devicetree binding), it is possible to estimate the dynamic power consumption of a CPU as P = C * V^2 * f, with C its capacitance and V and f respectively the voltage and frequency of the OPP. The Intelligent Power Allocator (IPA) thermal governor already implements that estimation method, in the thermal framework. However, this power estimation method can be applied to any platform where all the parameters are known (C, V and f), and not only those suffering thermal issues. As such, the code implementing this feature can be re-used to also populate the EM framework now used by EAS. As a first step, introduce in PM_OPP a helper function which CPUFreq drivers can use to register into the EM framework. This duplicates the power estimation done in IPA until it can be migrated to using the EM framework. This will be done later, once the EM framework has support for at least all platforms currently supported by IPA. Signed-off-by: Quentin Perret <quentin.perret@arm.com> Tested-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-02-07PM / OPP: Remove unused parameter of _generic_set_opp_clk_only()Viresh Kumar1-6/+5
The previous frequency value isn't getting used in the routine _generic_set_opp_clk_only(), drop it. Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-01-23OPP: Add support for parsing the 'opp-level' propertyRajendra Nayak3-0/+22
Now that the OPP bindings are updated to include an optional 'opp-level' property, add support to parse it from device tree and store it as part of dev_pm_opp structure. Also add and export an helper 'dev_pm_opp_get_level()' that can be used to get the level value read from device tree when present. Reviewed-by: Stephen Boyd <swboyd@chromium.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Andy Gross <andy.gross@linaro.org>
2019-01-04cpufreq: scpi/scmi: Fix freeing of dynamic OPPsViresh Kumar1-5/+58
Since the commit 2a4eb7358aba "OPP: Don't remove dynamic OPPs from _dev_pm_opp_remove_table()", dynamically created OPP aren't automatically removed anymore by dev_pm_opp_cpumask_remove_table(). This affects the scpi and scmi cpufreq drivers which no longer free OPPs on failures or on invocations of the policy->exit() callback. Create a generic OPP helper dev_pm_opp_remove_all_dynamic() which can be called from these drivers instead of dev_pm_opp_cpumask_remove_table(). In dev_pm_opp_remove_all_dynamic(), we need to make sure that the opp_list isn't getting accessed simultaneously from other parts of the OPP core while the helper is freeing dynamic OPPs, i.e. we can't drop the opp_table->lock while traversing through the OPP list. And to accomplish that, this patch also creates _opp_kref_release_unlocked() which can be called from this new helper with the opp_table lock already held. Cc: 4.20 <stable@vger.kernel.org> # v4.20 Reported-by: Valentin Schneider <valentin.schneider@arm.com> Fixes: 2a4eb7358aba "OPP: Don't remove dynamic OPPs from _dev_pm_opp_remove_table()" Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-14Merge branch 'opp/genpd/propagation' into opp/linux-nextViresh Kumar3-111/+552
2018-12-14OPP: Don't return 0 on error from of_get_required_opp_performance_state()Viresh Kumar1-5/+5
of_get_required_opp_performance_state() returns 0 on errors currently and a positive performance state otherwise. Since 0 is a valid performance state (representing off), it would be better if this routine returns negative values on error. That will also make it behave similar to dev_pm_opp_xlate_performance_state(), which also returns performance states and returns negative values on error. Change the return type of the function to "int" in order to return negative values. This doesn't have any users for now and so no other part of the kernel will be impacted with this change. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-12-14OPP: Add dev_pm_opp_xlate_performance_state() helperViresh Kumar1-0/+63
dev_pm_genpd_set_performance_state() needs to handle performance state propagation going forward. Currently this routine only gets the required performance state of the device's genpd as an argument, but it doesn't know how to translate that to master genpd(s) of the device's genpd. Introduce a new helper dev_pm_opp_xlate_performance_state() which will be used to translate from performance state of a device (or genpd sub-domain) to another device (or master genpd). Normally the src_table (of genpd sub-domain) will have the "required_opps" property set to point to one of the OPPs in the dst_table (of master genpd), but in some cases the genpd and its master have one to one mapping of performance states and so none of them have the "required-opps" property set. Return the performance state of the src_table as it is in such cases. Tested-by: Rajendra Nayak <rnayak@codeaurora.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-12-14OPP: Improve _find_table_of_opp_np()Viresh Kumar1-4/+10
Make _find_table_of_opp_np() more efficient by using of_get_parent() to find the parent OPP table node. Tested-by: Rajendra Nayak <rnayak@codeaurora.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-12-11OPP: Fix missing debugfs supply directory for OPPsViresh Kumar3-9/+29
There is one case where we may end up with no "supply" directory for the OPPs in debugfs. That happens when the OPP core isn't managing the regulators for the device and the device's OPP do have microvolt property. It happens because the opp_table->regulator_count remains set to 0 and the debugfs routines don't add any supply directory in such a case. This commit fixes that by setting opp_table->regulator_count to 1 in that particular case. But to make everything work nicely and not break other parts of the core, regulator_count is defined as "int" now instead of "unsigned int" and it can have different special values now. It is set to -1 initially to mark it "uninitialized" and later only we set it to 0 or positive values after checking how many supplies are there. This also helps in finding the bugs where only few of the OPPs have the "opp-microvolt" property set and not all. Fixes: 1fae788ed640 ("PM / OPP: Don't create debugfs "supply-0" directory unnecessarily") Reported-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-12-11OPP: Use opp_table->regulators to verify no regulator caseViresh Kumar1-4/+7
The value of opp_table->regulator_count is not very consistent right now and it may end up being 0 while we do have a "opp-microvolt" property in the OPP table. It was kept that way as we used to check if any regulators are set with the OPP core for a device or not using value of regulator_count. Lets use opp_table->regulators for that purpose as the meaning of regulator_count is going to change in the later patches. Reported-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-23OPP: Fix parsing of multiple phandles in "operating-points-v2" propertyViresh Kumar1-4/+2
We currently return error if more than one phandle is present in the "operating-points-v2" property, which is incorrect. We only want to check the count of phandles here and set index to 0 if only one phandle is present. Fix it. Fixes: 5ed4cecd75e9 ("OPP: Pass OPP table to _of_add_opp_table_v{1|2}()") Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-22opp: ti-opp-supply: Fix platform_no_drv_owner.cocci warningsYueHaibing1-1/+0
Remove .owner field if calls are used which set it automatically Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-13opp: ti-opp-supply: Correct the supply in _get_optimal_vdd_voltage callKeerthy1-1/+1
_get_optimal_vdd_voltage call provides new_supply_vbb->u_volt as the reference voltage while it should be really new_supply_vdd->u_volt. Cc: 4.16+ <stable@vger.kernel.org> # v4.16+ Fixes: 9a835fa6e47 ("PM / OPP: Add ti-opp-supply driver") Signed-off-by: Keerthy <j-keerthy@ti.com> Acked-by: Dave Gerlach <d-gerlach@ti.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-13opp: ti-opp-supply: Dynamically update u_volt_minKeerthy1-0/+3
The voltage range (min, max) provided in the device tree is from the data manual and is pretty big, catering to a wide range of devices. On a i2c read/write failure the regulator_set_voltage_triplet function falls back to set voltage between min and max. The min value from Device Tree can be lesser than the optimal value and in that case that can lead to a hang or crash. Hence set the u_volt_min dynamically to the optimal voltage value. Cc: 4.16+ <stable@vger.kernel.org> # v4.16+ Fixes: 9a835fa6e47 ("PM / OPP: Add ti-opp-supply driver") Signed-off-by: Keerthy <j-keerthy@ti.com> Acked-by: Dave Gerlach <d-gerlach@ti.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Remove of_dev_pm_opp_find_required_opp()Viresh Kumar1-54/+0
This isn't used anymore, remove it. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Rename and relocate of_genpd_opp_to_performance_state()Viresh Kumar1-0/+44
The OPP core already has the performance state values for each of the genpd's OPPs and there is no need to call the genpd callback again to get the performance state for the case where the end device doesn't have an OPP table and has the "required-opps" property directly in its node. This commit renames of_genpd_opp_to_performance_state() as of_get_required_opp_performance_state() and moves it to the OPP core, as it is all about OPP stuff now. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Configure all required OPPsViresh Kumar2-50/+68
Now that all the infrastructure is in place to support multiple required OPPs, lets switch over to using it. A new internal routine _set_required_opps() takes care of updating performance state for all the required OPPs. With this the performance state updates are supported even when the end device needs to configure regulators as well, that wasn't the case earlier. The pstates were earlier stored in the end device's OPP structures, that also changes now as those values are stored in the genpd's OPP structures. And so we switch over to using pm_genpd_opp_to_performance_state() instead of of_genpd_opp_to_performance_state() to get performance state for the genpd OPPs. The routine _generic_set_opp_domain() is not required anymore and is removed. On errors we don't try to recover by reverting to old settings as things are really complex now and the calls here should never really fail unless there is a bug. There is no point increasing the complexity, for code which will never be executed. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Add dev_pm_opp_{set|put}_genpd_virt_dev() helperViresh Kumar3-1/+107
Multiple generic power domains for a consumer device are supported with the help of virtual devices, which are created for each consumer device - genpd pair. These are the device structures which are attached to the power domain and are required by the OPP core to set the performance state of the genpd. The helpers added by this commit are required to be called once for each of these virtual devices. These are required only if multiple domains are available for a device, otherwise the actual device structure will be used instead by the OPP core. The new helpers also support the complex cases where the consumer device wouldn't always require all the domains. For example, a camera may require only one power domain during normal operations but two during high resolution operations. The consumer driver can call dev_pm_opp_put_genpd_virt_dev(high_resolution_genpd_virt_dev) if it is currently operating in the normal mode and doesn't have any performance requirements from the genpd which manages high resolution power requirements. The consumer driver can later call dev_pm_opp_set_genpd_virt_dev(high_resolution_genpd_virt_dev) once it switches back to the high resolution mode. The new helpers differ from other OPP set/put helpers as the new ones can be called with OPPs initialized for the table as we may need to call them on the fly because of the complex case explained above. For this reason it is possible that the genpd virt_dev structure may be used in parallel while the new helpers are running and a new mutex is added to protect against that. We didn't use the existing opp_table->lock mutex as that is widely used in the OPP core and we will need this lock in the dev_pm_opp_set_rate() helper while changing OPP and we need to make sure there is not much contention while doing that as that's the hotpath. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Populate OPPs from "required-opps" propertyViresh Kumar3-2/+86
An earlier commit populated the OPP tables from the "required-opps" property, this commit populates the individual OPPs. This is repeated for each OPP in the OPP table and these populated OPPs will be used by later commits. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Populate required opp tables from "required-opps" propertyViresh Kumar3-0/+157
The current implementation works only for the case where a single phandle is present in the "required-opps" property, while DT allows multiple phandles to be present there. This patch adds new infrastructure to parse all the phandles present in "required-opps" property and save pointers of the required OPP's OPP tables. These will be used by later commits. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Separate out custom OPP handler specific codeViresh Kumar1-27/+40
Create a separate routine to take care of custom set_opp() handler specific stuff. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-11-05OPP: Identify and mark genpd OPP tablesViresh Kumar2-2/+6
We need to handle genpd OPP tables differently, this is already the case at one location and will be extended going forward. Add another field to the OPP table to check if the table belongs to a genpd or not. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-10-04PM / OPP: _of_add_opp_table_v2(): increment count only if OPP is addedDave Gerlach1-13/+20
Currently the _of_add_opp_table_v2 call loops through the OPP nodes in the operating-points-v2 table in the device tree and calls _opp_add_static_v2 for each to add them to the table. It counts each iteration through this loop as an added OPP, however there are cases where _opp_add_static_v2() returns 0 but no new OPP is added to the list. This can happen while adding duplicate OPP or if the OPP isn't supported by hardware. Because of this the count variable will contain the number of OPP nodes in the table in device tree but not necessarily the ones that are actually added. As this count value is what is checked to determine if there are any valid OPPs, if a platform has an operating-points-v2 table with all OPP nodes containing opp-supported-hw values that are not currently supported, then _of_add_opp_table_v2 will fail to abort as it should due to an empty table. Additionally, since commit 3ba98324e81a ("PM / OPP: Get performance state using genpd helper"), the same count variable is compared against the number of OPPs containing performance states and requires that either all or none have pstates set, however in the case of any opp table that has any entries that do not get added by _opp_add_static_v2 due to incompatible opp-supported-hw fields, these numbers will not match and _of_add_opp_table_v2 will incorrectly fail. We need to clearly identify all the three cases (success, failure, unsupported/duplicate OPPs) and then increment count only on success case. Change return type of _opp_add_static_v2() to return the pointer to the newly added OPP instead of an integer. This routine now returns a valid pointer if the OPP is really added, NULL for unsupported or duplicate OPPs, and error value cased as a pointer on errors. Ideally the fixes tag in this commit should point back to the commit that introduced OPP v2 initially, as that's where we started incorrectly accounting for duplicate OPPs: commit 274659029c9d ("PM / OPP: Add support to parse "operating-points-v2" bindings") But it wasn't a real problem until recently as the count was only used to check if any OPPs are added or not. And so this commit points to a rather recent commit where we added more code that depends on the value of "count". Fixes: 3ba98324e81a ("PM / OPP: Get performance state using genpd helper") Reported-by: Dave Gerlach <d-gerlach@ti.com> Reported-by: Niklas Cassel <niklas.cassel@linaro.org> Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Dave Gerlach <d-gerlach@ti.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-10-04OPP: Return error on error from dev_pm_opp_get_opp_count()Viresh Kumar1-1/+1
Return error number instead of 0 on failures. Fixes: a1e8c13600bf ("PM / OPP: "opp-hz" is optional for power domains") Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-10-04OPP: Improve error handling in dev_pm_opp_of_cpumask_add_table()Viresh Kumar1-6/+12
The error handling wasn't appropriate in dev_pm_opp_of_cpumask_add_table(). For example it returns 0 on success and also for the case where cpumask is empty or cpu_device wasn't found for any of the CPUs. It should really return error on such cases, so that the callers can be aware of the outcome. Fix it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-10-01OPP: Pass OPP table to _of_add_opp_table_v{1|2}()Viresh Kumar1-40/+28
Both _of_add_opp_table_v1() and _of_add_opp_table_v2() contain similar code to get the OPP table and their parent routine also parses the DT to find the OPP table's node pointer. This can be simplified by getting the OPP table in advance and then passing it as argument to these routines. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-10-01OPP: Prevent creating multiple OPP tables for devices sharing OPP nodesViresh Kumar3-25/+37
When two or more devices are sharing their clock and voltage rails, they share the same OPP table. But there are some corner cases where the OPP core incorrectly creates separate OPP tables for them. For example, CPU 0 and 1 share clock/voltage rails. The platform specific code calls dev_pm_opp_set_regulators() for CPU0 and the OPP core creates an OPP table for it (the individual OPPs aren't initialized as of now). The same is repeated for CPU1 then. Because _opp_get_opp_table() doesn't compare DT node pointers currently, it fails to find the link between CPU0 and CPU1 and so creates a new OPP table. Fix this by calling _managed_opp() from _opp_get_opp_table(). _managed_opp() gain an additional argument (index) to get the right node pointer. This resulted in simplifying code in _of_add_opp_table_v2() as well. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Use a single mechanism to free the OPP tableViresh Kumar3-53/+35
Currently there are two separate ways to free the OPP table based on how it is created in the first place. We call _dev_pm_opp_remove_table() to free the static and/or dynamic OPP, OPP list devices, etc. This is done for the case where the OPP table is added while initializing the OPPs, like via the path dev_pm_opp_of_add_table(). We also call dev_pm_opp_put_opp_table() in some cases which eventually frees the OPP table structure once the reference count reaches 0. This is used by the first case as well as other cases like dev_pm_opp_set_regulators() where the OPPs aren't necessarily initialized at this point. This whole thing is a bit unclear and messy and obstruct any further cleanup/fixup of OPP core. This patch tries to streamline this by keeping a single path for OPP table destruction, i.e. dev_pm_opp_put_opp_table(). All the cleanup happens in _opp_table_kref_release() now after the reference count reaches 0. _dev_pm_opp_remove_table() is removed as it isn't required anymore. We don't drop the reference to the OPP table after creating it from _of_add_opp_table_v{1|2}() anymore and the same is dropped only when we try to remove them. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Don't remove dynamic OPPs from _dev_pm_opp_remove_table()Viresh Kumar4-30/+17
Only one platform was depending on this feature and it is already updated now. Stop removing dynamic OPPs from _dev_pm_opp_remove_table(). This simplifies lot of paths and removes unnecessary parameters. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Create separate kref for static OPPs listViresh Kumar3-1/+42
The static OPPs don't always get freed with the OPP table, it can happen before that as well. For example, if the OPP table is first created using helpers like dev_pm_opp_set_supported_hw() and the OPPs are created at a later point. Now when the OPPs are removed, the OPP table stays until the time dev_pm_opp_put_supported_hw() is called. Later patches will streamline the freeing of OPP table and that requires the static OPPs to get freed with help of a separate kernel reference. This patch prepares for that by creating a separate kref for static OPPs list. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Don't take OPP table's kref for static OPPsViresh Kumar1-5/+6
The reference count is only required to be incremented for every call that may lead to adding the OPP table. For static OPPs the same should be done from the parent routine which adds all static OPPs together and so only one refcount for all static OPPs. Update code to reflect that. The refcount is incremented every time a dynamic OPP is created (as that can lead to creating the OPP table) and the same is dropped when the OPP is removed. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Parse OPP table's DT properties from _of_init_opp_table()Viresh Kumar2-31/+50
Parse the DT properties present in the OPP table from _of_init_opp_table(), which is a dedicated routine for DT parsing. Minor relocation of helpers is required for this. It is possible now for _managed_opp() to return a partially initialized OPP table if the OPP table is created via the helpers like dev_pm_opp_set_supported_hw() and we need another flag to indicate if the static OPP are already parsed or not to make sure we don't incorrectly skip initializing the static OPPs. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Pass index to _of_init_opp_table()Viresh Kumar3-11/+24
This is a preparatory patch required for the next commit which will start using OPP table's node pointer in _of_init_opp_table(), which requires the index in order to read the OPP table's phandle. This commit adds the index argument in the call chains in order to get it delivered to _of_init_opp_table(). Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Protect dev_list with opp_table lockViresh Kumar3-3/+22
The dev_list needs to be protected with a lock, else we may have simultaneous access (addition/removal) to it and that would be racy. Extend scope of the opp_table lock to protect dev_list as well. Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Don't try to remove all OPP tables on failureViresh Kumar3-5/+9
dev_pm_opp_of_cpumask_add_table() creates the OPP table for all CPUs present in the cpumask and on errors it should revert all changes it has done. It actually is doing a bit more than that. On errors, it tries to free all the OPP tables, even the one it hasn't created yet. This may also end up freeing the OPP tables which were created from separate path, like dev_pm_opp_set_supported_hw(). Reported-and-tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-09-20OPP: Free OPP table properly on performance state irregularitiesViresh Kumar1-0/+1
The OPP table was freed, but not the individual OPPs which is done from _dev_pm_opp_remove_table(). Fix it by calling _dev_pm_opp_remove_table() as well. Cc: 4.18 <stable@vger.kernel.org> # v4.18 Fixes: 3ba98324e81a ("PM / OPP: Get performance state using genpd helper") Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-06-19PM / OPP: Update voltage in case freq == old_freqWaldemar Rymarkiewicz1-1/+1
This commit fixes a rare but possible case when the clk rate is updated without update of the regulator voltage. At boot up, CPUfreq checks if the system is running at the right freq. This is a sanity check in case a bootloader set clk rate that is outside of freq table present with cpufreq core. In such cases system can be unstable so better to change it to a freq that is preset in freq-table. The CPUfreq takes next freq that is >= policy->cur and this is our target_freq that needs to be set now. dev_pm_opp_set_rate(dev, target_freq) checks the target_freq and the old_freq (a current rate). If these are equal it returns early. If not, it searches for OPP (old_opp) that fits best to old_freq (not listed in the table) and updates old_freq (!). Here, we can end up with old_freq = old_opp.rate = target_freq, which is not handled in _generic_set_opp_regulator(). It's supposed to update voltage only when freq > old_freq || freq > old_freq. if (freq > old_freq) { ret = _set_opp_voltage(dev, reg, new_supply); [...] if (freq < old_freq) { ret = _set_opp_voltage(dev, reg, new_supply); if (ret) It results in, no voltage update while clk rate is updated. Example: freq-table = { 1000MHz 1.15V 666MHZ 1.10V 333MHz 1.05V } boot-up-freq = 800MHz # not listed in freq-table freq = target_freq = 1GHz old_freq = 800Mhz old_opp = _find_freq_ceil(opp_table, &old_freq); #(old_freq is modified!) old_freq = 1GHz Fixes: 6a0712f6f199 ("PM / OPP: Add dev_pm_opp_set_rate()") Cc: 4.6+ <stable@vger.kernel.org> # v4.6+ Signed-off-by: Waldemar Rymarkiewicz <waldemar.rymarkiewicz@gmail.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-06-13treewide: kzalloc() -> kcalloc()Kees Cook1-2/+2
The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-05-30OPP: Allow same OPP table to be used for multiple genpdViresh Kumar1-2/+15
The OPP binding says: Property: operating-points-v2 ... This can contain more than one phandle for power domain providers that provide multiple power domains. That is, one phandle for each power domain. If only one phandle is available, then the same OPP table will be used for all power domains provided by the power domain provider. But the OPP core isn't allowing the same OPP table to be used for multiple domains. Update dev_pm_opp_of_add_table_indexed() to allow that. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Rajendra Nayak <rnayak@codeaurora.org>
2018-05-22PM / OPP: Fix shared OPP table support in dev_pm_opp_register_set_opp_helper()Viresh Kumar1-22/+5
It should be fine to call dev_pm_opp_register_set_opp_helper() for all possible CPUs, even if some of them share the OPP table as the caller may not be aware of sharing policy. Lets increment the reference count of the OPP table and return its pointer. The caller need to call dev_pm_opp_register_put_opp_helper() the same number of times later on to drop all the references. To avoid adding another counter to count how many times dev_pm_opp_register_set_opp_helper() is called for the same OPP table, dev_pm_opp_register_put_opp_helper() frees the resources on the very first call made to it, assuming that the caller would be calling it sequentially for all the CPUs. We can revisit that if that assumption is broken in the future. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-05-22PM / OPP: Fix shared OPP table support in dev_pm_opp_set_regulators()Viresh Kumar1-9/+6
It should be fine to call dev_pm_opp_set_regulators() for all possible CPUs, even if some of them share the OPP table as the caller may not be aware of sharing policy. Lets increment the reference count of the OPP table and return its pointer. The caller need to call dev_pm_opp_put_regulators() the same number of times later on to drop all the references. To avoid adding another counter to count how many times dev_pm_opp_set_regulators() is called for the same OPP table, dev_pm_opp_put_regulators() frees the resources on the very first call made to it, assuming that the caller would be calling it sequentially for all the CPUs. We can revisit that if that assumption is broken in the future. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-05-22PM / OPP: Fix shared OPP table support in dev_pm_opp_set_prop_name()Viresh Kumar1-20/+5
It should be fine to call dev_pm_opp_set_prop_name() for all possible CPUs, even if some of them share the OPP table as the caller may not be aware of sharing policy. Lets increment the reference count of the OPP table and return its pointer. The caller need to call dev_pm_opp_put_prop_name() the same number of times later on to drop all the references. To avoid adding another counter to count how many times dev_pm_opp_set_prop_name() is called for the same OPP table, dev_pm_opp_put_prop_name() frees the resources on the very first call made to it, assuming that the caller would be calling it sequentially for all the CPUs. We can revisit that if that assumption is broken in the future. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-05-22PM / OPP: Fix shared OPP table support in dev_pm_opp_set_supported_hw()Viresh Kumar1-21/+5
It should be fine to call dev_pm_opp_set_supported_hw() for all possible CPUs, even if some of them share the OPP table as the caller may not be aware of sharing policy. Lets increment the reference count of the OPP table and return its pointer. The caller need to call dev_pm_opp_put_supported_hw() the same number of times later on to drop all the references. To avoid adding another counter to count how many times dev_pm_opp_set_supported_hw() is called for the same OPP table, dev_pm_opp_put_supported_hw() frees the resources on the very first call made to it, assuming that the caller would be calling it sequentially for all the CPUs. We can revisit that if that assumption is broken in the future. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2018-05-16PM / OPP: silence an uninitialized variable warningDan Carpenter1-1/+1
Smatch complains that it's possible we print "rate" in the debug output when it hasn't been initialized. It should be zero on that path. Fixes: a1e8c13600bf ("PM / OPP: "opp-hz" is optional for power domains") [ Viresh: Added the Fixes tag ] Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>