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2024-01-10PM: sleep: Restore asynchronous device resume optimizationRafael J. Wysocki1-0/+1
Before commit 7839d0078e0d ("PM: sleep: Fix possible deadlocks in core system-wide PM code"), the resume of devices that were allowed to resume asynchronously was scheduled before starting the resume of the other devices, so the former did not have to wait for the latter unless functional dependencies were present. Commit 7839d0078e0d removed that optimization in order to address a correctness issue, but it can be restored with the help of a new device power management flag, so do that now. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
2023-10-26Merge branches 'pm-sleep', 'powercap' and 'pm-tools'Rafael J. Wysocki1-14/+29
Merge updates related to system sleep handling, one power capping update and one PM utility update for 6.7-rc1: - Use __get_safe_page() rather than touching the list in hibernation snapshot code (Brian Geffon). - Fix symbol export for _SIMPLE_ variants of _PM_OPS() (Raag Jadav). - Clean up sync_read handling in snapshot_write_next() (Brian Geffon). - Fix kerneldoc comments for swsusp_check() and swsusp_close() to better match code (Christoph Hellwig). - Downgrade BIOS locked limits pr_warn() in the Intel RAPL power capping driver to pr_debug() (Ville Syrjälä). - Change the minimum python version for the intel_pstate_tracer utility from 2.7 to 3.6 (Doug Smythies). * pm-sleep: PM: hibernate: fix the kerneldoc comment for swsusp_check() and swsusp_close() PM: hibernate: Clean up sync_read handling in snapshot_write_next() PM: sleep: Fix symbol export for _SIMPLE_ variants of _PM_OPS() PM: hibernate: Use __get_safe_page() rather than touching the list * powercap: powercap: intel_rapl: Downgrade BIOS locked limits pr_warn() to pr_debug() * pm-tools: tools/power/x86/intel_pstate_tracer: python minimum version
2023-10-06PM: domains: Introduce dev_pm_domain_set_performance_state()Ulf Hansson1-0/+2
The generic PM domain is currently the only PM domain variant that supports performance scaling. To allow performance scaling to be supported through a common interface, let's add an optional callback ->set_performance_state(), in the struct dev_pm_domain. Moreover, let's add a function, dev_pm_domain_set_performance_state(), that may be called by consumers to request a new performance state for a device through its PM domain. Note that, in most cases it's preferred that a consumer use the OPP library to request a new performance state for its device. Although, this requires some additional changes to be supported, which are being implemented from subsequent changes. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2023-09-26PM: sleep: Fix symbol export for _SIMPLE_ variants of _PM_OPS()Raag Jadav1-14/+29
Currently EXPORT_*_SIMPLE_DEV_PM_OPS() use EXPORT_*_DEV_PM_OPS() set of macros to export dev_pm_ops symbol, which export the symbol in case CONFIG_PM=y but don't take CONFIG_PM_SLEEP into consideration. Since _SIMPLE_ variants of _PM_OPS() do not include runtime PM handles and are only used in case CONFIG_PM_SLEEP=y, we should not be exporting dev_pm_ops symbol for them in case CONFIG_PM_SLEEP=n. This can be fixed by having two distinct set of export macros for both _RUNTIME_ and _SIMPLE_ variants of _PM_OPS(), such that the export of dev_pm_ops symbol used in each variant depends on CONFIG_PM and CONFIG_PM_SLEEP respectively. Introduce _DEV_SLEEP_PM_OPS() set of export macros for _SIMPLE_ variants of _PM_OPS(), which export dev_pm_ops symbol only in case CONFIG_PM_SLEEP=y and discard it otherwise. Fixes: 34e1ed189fab ("PM: Improve EXPORT_*_DEV_PM_OPS macros") Signed-off-by: Raag Jadav <raag.jadav@intel.com> Reviewed-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-08-21pm: Introduce DEFINE_NOIRQ_DEV_PM_OPS() helperAndy Shevchenko1-0/+9
_DEFINE_DEV_PM_OPS() helps to define PM operations for the system sleep and/or runtime PM cases. Some of the existing users want to have _noirq() variants to be set. For that purpose introduce a new helper which sets up _noirq() callbacks to be assigned and struct dev_pm_ops be provided. Acked-by: "Rafael J. Wysocki" <rafael@kernel.org> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20230717172821.62827-2-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2023-06-22linux/export.h: rename 'sec' argument to 'license'Masahiro Yamada1-3/+3
Now, EXPORT_SYMBOL() is populated in two stages. In the first stage, all of EXPORT_SYMBOL/EXPORT_SYMBOL_GPL go into the same section, '.export_symbol'. 'sec' does not make sense any more. Rename it to 'license'. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2023-06-22kbuild: generate KSYMTAB entries by modpostMasahiro Yamada1-2/+2
Commit 7b4537199a4a ("kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS") made modpost output CRCs in the same way whether the EXPORT_SYMBOL() is placed in *.c or *.S. For further cleanups, this commit applies a similar approach to the entire data structure of EXPORT_SYMBOL(). The EXPORT_SYMBOL() compilation is split into two stages. When a source file is compiled, EXPORT_SYMBOL() will be converted into a dummy symbol in the .export_symbol section. For example, EXPORT_SYMBOL(foo); EXPORT_SYMBOL_NS_GPL(bar, BAR_NAMESPACE); will be encoded into the following assembly code: .section ".export_symbol","a" __export_symbol_foo: .asciz "" /* license */ .asciz "" /* name space */ .balign 8 .quad foo /* symbol reference */ .previous .section ".export_symbol","a" __export_symbol_bar: .asciz "GPL" /* license */ .asciz "BAR_NAMESPACE" /* name space */ .balign 8 .quad bar /* symbol reference */ .previous They are mere markers to tell modpost the name, license, and namespace of the symbols. They will be dropped from the final vmlinux and modules because the *(.export_symbol) will go into /DISCARD/ in the linker script. Then, modpost extracts all the information about EXPORT_SYMBOL() from the .export_symbol section, and generates the final C code: KSYMTAB_FUNC(foo, "", ""); KSYMTAB_FUNC(bar, "_gpl", "BAR_NAMESPACE"); KSYMTAB_FUNC() (or KSYMTAB_DATA() if it is data) is expanded to struct kernel_symbol that will be linked to the vmlinux or a module. With this change, EXPORT_SYMBOL() works in the same way for *.c and *.S files, providing the following benefits. [1] Deprecate EXPORT_DATA_SYMBOL() In the old days, EXPORT_SYMBOL() was only available in C files. To export a symbol in *.S, EXPORT_SYMBOL() was placed in a separate *.c file. arch/arm/kernel/armksyms.c is one example written in the classic manner. Commit 22823ab419d8 ("EXPORT_SYMBOL() for asm") removed this limitation. Since then, EXPORT_SYMBOL() can be placed close to the symbol definition in *.S files. It was a nice improvement. However, as that commit mentioned, you need to use EXPORT_DATA_SYMBOL() for data objects on some architectures. In the new approach, modpost checks symbol's type (STT_FUNC or not), and outputs KSYMTAB_FUNC() or KSYMTAB_DATA() accordingly. There are only two users of EXPORT_DATA_SYMBOL: EXPORT_DATA_SYMBOL_GPL(empty_zero_page) (arch/ia64/kernel/head.S) EXPORT_DATA_SYMBOL(ia64_ivt) (arch/ia64/kernel/ivt.S) They are transformed as follows and output into .vmlinux.export.c KSYMTAB_DATA(empty_zero_page, "_gpl", ""); KSYMTAB_DATA(ia64_ivt, "", ""); The other EXPORT_SYMBOL users in ia64 assembly are output as KSYMTAB_FUNC(). EXPORT_DATA_SYMBOL() is now deprecated. [2] merge <linux/export.h> and <asm-generic/export.h> There are two similar header implementations: include/linux/export.h for .c files include/asm-generic/export.h for .S files Ideally, the functionality should be consistent between them, but they tend to diverge. Commit 8651ec01daed ("module: add support for symbol namespaces.") did not support the namespace for *.S files. This commit shifts the essential implementation part to C, which supports EXPORT_SYMBOL_NS() for *.S files. <asm/export.h> and <asm-generic/export.h> will remain as a wrapper of <linux/export.h> for a while. They will be removed after #include <asm/export.h> directives are all replaced with #include <linux/export.h>. [3] Implement CONFIG_TRIM_UNUSED_KSYMS in one-pass algorithm (by a later commit) When CONFIG_TRIM_UNUSED_KSYMS is enabled, Kbuild recursively traverses the directory tree to determine which EXPORT_SYMBOL to trim. If an EXPORT_SYMBOL turns out to be unused by anyone, Kbuild begins the second traverse, where some source files are recompiled with their EXPORT_SYMBOL() tuned into a no-op. We can do this better now; modpost can selectively emit KSYMTAB entries that are really used by modules. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2023-02-13PM: Add EXPORT macros for exporting PM functionsRichard Fitzgerald1-0/+4
Add a pair of macros for exporting functions only if CONFIG_PM is enabled. The naming follows the style of the standard EXPORT_SYMBOL_*() macros that they replace. Sometimes a module wants to export PM functions directly to other drivers, not a complete struct dev_pm_ops. A typical example is where a core library exports the generic (shared) implementation and calling code wraps one or more of these in custom code. Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-10-04PM: Improve EXPORT_*_DEV_PM_OPS macrosPaul Cercueil1-14/+23
Update the _EXPORT_DEV_PM_OPS() internal macro. It was not used anywhere outside pm.h and pm_runtime.h, so it is safe to update it. Before, this macro would take a few parameters to be used as sleep and runtime callbacks. This made it unsuitable to use with different callbacks, for instance the "noirq" ones. It is now semantically different: instead of creating a conditionally exported dev_pm_ops structure, it only contains part of the definition. This macro should however never be used directly (hence the trailing underscore). Instead, the following four macros are provided: - EXPORT_DEV_PM_OPS(name) - EXPORT_GPL_DEV_PM_OPS(name) - EXPORT_NS_DEV_PM_OPS(name, ns) - EXPORT_NS_GPL_DEV_PM_OPS(name, ns) For instance, it is now possible to conditionally export noirq suspend/resume PM functions like this: EXPORT_GPL_DEV_PM_OPS(foo_pm_ops) = { NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) }; The existing helper macros EXPORT_*_SIMPLE_DEV_PM_OPS() and EXPORT_*_RUNTIME_DEV_PM_OPS() have been updated to use these new macros. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-30Merge tag 'pm-5.19-rc1-2' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "These update the ARM cpufreq drivers and fix up the CPPC cpufreq driver after recent changes, update the OPP code and PM documentation and add power sequences support to the system reboot and power off code. Specifics: - Add Tegra234 cpufreq support (Sumit Gupta) - Clean up and enhance the Mediatek cpufreq driver (Wan Jiabing, Rex-BC Chen, and Jia-Wei Chang) - Fix up the CPPC cpufreq driver after recent changes (Zheng Bin, Pierre Gondois) - Minor update to dt-binding for Qcom's opp-v2-kryo-cpu (Yassine Oudjana) - Use list iterator only inside the list_for_each_entry loop (Xiaomeng Tong, and Jakob Koschel) - New APIs related to finding OPP based on interconnect bandwidth (Krzysztof Kozlowski) - Fix the missing of_node_put() in _bandwidth_supported() (Dan Carpenter) - Cleanups (Krzysztof Kozlowski, and Viresh Kumar) - Add Out of Band mode description to the intel-speed-select utility documentation (Srinivas Pandruvada) - Add power sequences support to the system reboot and power off code and make related platform-specific changes for multiple platforms (Dmitry Osipenko, Geert Uytterhoeven)" * tag 'pm-5.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (60 commits) cpufreq: CPPC: Fix unused-function warning cpufreq: CPPC: Fix build error without CONFIG_ACPI_CPPC_CPUFREQ_FIE Documentation: admin-guide: PM: Add Out of Band mode kernel/reboot: Change registration order of legacy power-off handler m68k: virt: Switch to new sys-off handler API kernel/reboot: Add devm_register_restart_handler() kernel/reboot: Add devm_register_power_off_handler() soc/tegra: pmc: Use sys-off handler API to power off Nexus 7 properly reboot: Remove pm_power_off_prepare() regulator: pfuze100: Use devm_register_sys_off_handler() ACPI: power: Switch to sys-off handler API memory: emif: Use kernel_can_power_off() mips: Use do_kernel_power_off() ia64: Use do_kernel_power_off() x86: Use do_kernel_power_off() sh: Use do_kernel_power_off() m68k: Switch to new sys-off handler API powerpc: Use do_kernel_power_off() xen/x86: Use do_kernel_power_off() parisc: Use do_kernel_power_off() ...
2022-05-28Merge tag 'cxl-for-5.19' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl Pull cxl updates from Dan Williams: "Compute Express Link (CXL) updates for this cycle. The highlight is new driver-core infrastructure and CXL subsystem changes for allowing lockdep to validate device_lock() usage. Thanks to PeterZ for setting me straight on the current capabilities of the lockdep API, and Greg acked it as well. On the CXL ACPI side this update adds support for CXL _OSC so that platform firmware knows that it is safe to still grant Linux native control of PCIe hotplug and error handling in the presence of CXL devices. A circular dependency problem was discovered between suspend and CXL memory for cases where the suspend image might be stored in CXL memory where that image also contains the PCI register state to restore to re-enable the device. Disable suspend for now until an architecture is defined to clarify that conflict. Lastly a collection of reworks, fixes, and cleanups to the CXL subsystem where support for snooping mailbox commands and properly handling the "mem_enable" flow are the highlights. Summary: - Add driver-core infrastructure for lockdep validation of device_lock(), and fixup a deadlock report that was previously hidden behind the 'lockdep no validate' policy. - Add CXL _OSC support for claiming native control of CXL hotplug and error handling. - Disable suspend in the presence of CXL memory unless and until a protocol is identified for restoring PCI device context from memory hosted on CXL PCI devices. - Add support for snooping CXL mailbox commands to protect against inopportune changes, like set-partition with the 'immediate' flag set. - Rework how the driver detects legacy CXL 1.1 configurations (CXL DVSEC / 'mem_enable') before enabling new CXL 2.0 decode configurations (CXL HDM Capability). - Miscellaneous cleanups and fixes from -next exposure" * tag 'cxl-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (47 commits) cxl/port: Enable HDM Capability after validating DVSEC Ranges cxl/port: Reuse 'struct cxl_hdm' context for hdm init cxl/port: Move endpoint HDM Decoder Capability init to port driver cxl/pci: Drop @info argument to cxl_hdm_decode_init() cxl/mem: Merge cxl_dvsec_ranges() and cxl_hdm_decode_init() cxl/mem: Skip range enumeration if mem_enable clear cxl/mem: Consolidate CXL DVSEC Range enumeration in the core cxl/pci: Move cxl_await_media_ready() to the core cxl/mem: Validate port connectivity before dvsec ranges cxl/mem: Fix cxl_mem_probe() error exit cxl/pci: Drop wait_for_valid() from cxl_await_media_ready() cxl/pci: Consolidate wait_for_media() and wait_for_media_ready() cxl/mem: Drop mem_enabled check from wait_for_media() nvdimm: Fix firmware activation deadlock scenarios device-core: Kill the lockdep_mutex nvdimm: Drop nd_device_lock() ACPI: NFIT: Drop nfit_device_lock() nvdimm: Replace lockdep_mutex with local lock classes cxl: Drop cxl_device_lock() cxl/acpi: Add root device lockdep validation ...
2022-05-25Merge back reboot/poweroff notifiers rework for 5.19-rc1.Rafael J. Wysocki1-1/+0
2022-05-19reboot: Remove pm_power_off_prepare()Dmitry Osipenko1-1/+0
All pm_power_off_prepare() users were converted to sys-off handler API. Remove the obsolete global callback variable. Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-23PM: CXL: Disable suspendDan Williams1-0/+9
The CXL specification claims S3 support at a hardware level, but at a system software level there are some missing pieces. Section 9.4 (CXL 2.0) rightly claims that "CXL mem adapters may need aux power to retain memory context across S3", but there is no enumeration mechanism for the OS to determine if a given adapter has that support. Moreover the save state and resume image for the system may inadvertantly end up in a CXL device that needs to be restored before the save state is recoverable. I.e. a circular dependency that is not resolvable without a third party save-area. Arrange for the cxl_mem driver to fail S3 attempts. This still nominaly allows for suspend, but requires unbinding all CXL memory devices before the suspend to ensure the typical DRAM flow is taken. The cxl_mem unbind flow is intended to also tear down all CXL memory regions associated with a given cxl_memdev. It is reasonable to assume that any device participating in a System RAM range published in the EFI memory map is covered by aux power and save-area outside the device itself. So this restriction can be minimized in the future once pre-existing region enumeration support arrives, and perhaps a spec update to clarify if the EFI memory map is sufficent for determining the range of devices managed by platform-firmware for S3 support. Per Rafael, if the CXL configuration prevents suspend then it should fail early before tasks are frozen, and mem_sleep should stop showing 'mem' as an option [1]. Effectively CXL augments the platform suspend ->valid() op since, for example, the ACPI ops are not aware of the CXL / PCI dependencies. Given the split role of platform firmware vs OS provisioned CXL memory it is up to the cxl_mem driver to determine if the CXL configuration has elements that platform firmware may not be prepared to restore. Link: https://lore.kernel.org/r/CAJZ5v0hGVN_=3iU8OLpHY3Ak35T5+JcBM-qs8SbojKrpd0VXsA@mail.gmail.com [1] Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Len Brown <len.brown@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/165066828317.3907920.5690432272182042556.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-04-05PM: core: Add NS varients of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and runtime pm equivJonathan Cameron1-5/+9
As more drivers start to use namespaces, we need to have varients of these useful macros that allow the export to be in a particular namespace. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-08PM: sleep: Add device name to suspend_report_result()Youngjin Jang1-4/+4
Currently, suspend_report_result() prints only function information. If any driver uses a common PM function, nobody knows who exactly called the failing function. A device pinter is needed to recognize the failing device. For example: PM: dpm_run_callback(): pnp_bus_suspend+0x0/0x10 returns 0 PM: dpm_run_callback(): pci_pm_suspend+0x0/0x150 returns 0 become after the change: serial 00:05: PM: dpm_run_callback(): pnp_bus_suspend+0x0/0x10 returns 0 pci 0000:00:01.3: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x150 returns 0 Signed-off-by: Youngjin Jang <yj84.jang@samsung.com> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-01-12PM: runtime: Add DEFINE_RUNTIME_DEV_PM_OPS() macroPaul Cercueil1-1/+2
A lot of drivers create a dev_pm_ops struct with the system sleep suspend/resume callbacks set to pm_runtime_force_suspend() and pm_runtime_force_resume(). These drivers can now use the DEFINE_RUNTIME_DEV_PM_OPS() macro, which will use pm_runtime_force_{suspend,resume}() as the system sleep callbacks, while having the same dead code removal characteristic that is already provided by DEFINE_SIMPLE_DEV_PM_OPS(). Signed-off-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-01-12PM: core: Add EXPORT[_GPL]_SIMPLE_DEV_PM_OPS macrosPaul Cercueil1-3/+32
These macros are defined conditionally, according to CONFIG_PM: - if CONFIG_PM is enabled, these macros resolve to DEFINE_SIMPLE_DEV_PM_OPS(), and the dev_pm_ops symbol will be exported. - if CONFIG_PM is disabled, these macros will result in a dummy static dev_pm_ops to be created with the __maybe_unused flag. The dev_pm_ops will then be discarded by the compiler, along with the provided callback functions if they are not used anywhere else. In the second case, the symbol is not exported, which should be perfectly fine - users of the symbol should all use the pm_ptr() or pm_sleep_ptr() macro, so the dev_pm_ops marked as "extern" in the client's code will never be accessed. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-01-12PM: core: Remove static qualifier in DEFINE_SIMPLE_DEV_PM_OPS macroPaul Cercueil1-1/+1
Keep this macro in line with the other ones. This makes it possible to use them in the cases where the underlying dev_pm_ops structure is exported. Restore the "static" qualifier in the two drivers where the DEFINE_SIMPLE_DEV_PM_OPS macro was used. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-01-12PM: core: Remove DEFINE_UNIVERSAL_DEV_PM_OPS() macroPaul Cercueil1-13/+8
The deprecated UNIVERSAL_DEV_PM_OPS() macro uses the provided callbacks for both runtime PM and system sleep, which is very likely to be a mistake, as a system sleep can be triggered while a given device is already PM-suspended, which would cause the suspend callback to be called twice. The amount of users of UNIVERSAL_DEV_PM_OPS() is also tiny (16 occurences) compared to the number of places where SET_SYSTEM_SLEEP_PM_OPS() is used with pm_runtime_force_suspend() and pm_runtime_force_resume(), which makes me think that none of these cases are actually valid. As the new macro DEFINE_UNIVERSAL_DEV_PM_OPS() which was introduced to replace UNIVERSAL_DEV_PM_OPS() is currently unused, remove it before someone starts to use it in yet another invalid case. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-17PM: runtime: Capture device status before disabling runtime PMRafael J. Wysocki1-0/+2
In some cases (for example, during system-wide suspend and resume of devices) it is useful to know whether or not runtime PM has ever been enabled for a given device and, if so, what the runtime PM status of it had been right before runtime PM was disabled for it last time. For this reason, introduce a new struct dev_pm_info field called last_status that will be used for capturing the runtime PM status of the device when its power.disable_depth counter changes from 0 to 1. The new field will be set to RPM_INVALID to start with and whenever power.disable_depth changes from 1 to 0, so it will be valid only when runtime PM of the device is currently disabled, but it has been enabled at least once. Immediately use power.last_status in rpm_resume() to make it handle the case when PM runtime is disabled for the device, but its runtime PM status is RPM_ACTIVE more consistently. Namely, make it return 1 if power.last_status is also equal to RPM_ACTIVE in that case (the idea being that if the status was RPM_ACTIVE last time when power.disable_depth was changing from 0 to 1 and it is still RPM_ACTIVE, it can be assumed to reflect what happened to the device last time when it was using runtime PM) and -EACCES otherwise. Update the documentation to provide a description of last_status and change the description of pm_runtime_resume() in it to reflect the new behavior of rpm_active(). While at it, rearrange the code in pm_runtime_enable() to be more straightforward and replace the WARN() macro in it with a pr_warn() invocation which is less disruptive. Link: https://lore.kernel.org/linux-pm/20211026222626.39222-1-ulf.hansson@linaro.org/t/#u Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-17PM: core: Add new *_PM_OPS macros, deprecate old onesPaul Cercueil1-24/+50
This commit introduces the following macros: SYSTEM_SLEEP_PM_OPS() LATE_SYSTEM_SLEEP_PM_OPS() NOIRQ_SYSTEM_SLEEP_PM_OPS() RUNTIME_PM_OPS() These new macros are very similar to their SET_*_PM_OPS() equivalent. They however differ in the fact that the callbacks they set will always be seen as referenced by the compiler. This means that the callback functions don't need to be wrapped with a #ifdef CONFIG_PM guard, or tagged with __maybe_unused, to prevent the compiler from complaining about unused static symbols. The compiler will then simply evaluate at compile time whether or not these symbols are dead code. The callbacks that are only useful with CONFIG_PM_SLEEP is enabled, are now also wrapped with a new pm_sleep_ptr() macro, which is inspired from pm_ptr(). This is needed for drivers that use different callbacks for sleep and runtime PM, to handle the case where CONFIG_PM is set and CONFIG_PM_SLEEP is not. This commit also deprecates the following macros: SIMPLE_DEV_PM_OPS() UNIVERSAL_DEV_PM_OPS() And introduces the following macros: DEFINE_SIMPLE_DEV_PM_OPS() DEFINE_UNIVERSAL_DEV_PM_OPS() These macros are similar to the functions they were created to replace, with the following differences: - They use the new macros introduced above, and as such always reference the provided callback functions. - They are not tagged with __maybe_unused. They are meant to be used with pm_ptr() or pm_sleep_ptr() for DEFINE_UNIVERSAL_DEV_PM_OPS() and DEFINE_SIMPLE_DEV_PM_OPS() respectively. - They declare the symbol static, since every driver seems to do that anyway; and if a non-static use-case is needed an indirection pointer could be used. The point of this change, is to progressively switch from a code model where PM callbacks are all protected behind CONFIG_PM guards, to a code model where the PM callbacks are always seen by the compiler, but discarded if not used. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-17PM: core: Redefine pm_ptr() macroPaul Cercueil1-5/+1
The pm_ptr() macro was previously conditionally defined, according to the value of the CONFIG_PM option. This meant that the pointed structure was either referenced (if CONFIG_PM was set), or never referenced (if CONFIG_PM was not set), causing it to be detected as unused by the compiler. This worked fine, but required the __maybe_unused compiler attribute to be used to every symbol pointed to by a pointer wrapped with pm_ptr(). We can do better. With this change, the pm_ptr() is now defined the same, independently of the value of CONFIG_PM. It now uses the (?:) ternary operator to conditionally resolve to its argument. Since the condition is known at compile time, the compiler will then choose to discard the unused symbols, which won't need to be tagged with __maybe_unused anymore. This pm_ptr() macro is usually used with pointers to dev_pm_ops structures created with SIMPLE_DEV_PM_OPS() or similar macros. These do use a __maybe_unused flag, which is now useless with this change, so it later can be removed. However in the meantime it causes no harm, and all the drivers still compile fine with the new pm_ptr() macro. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-05-10PM: runtime: Fix unpaired parent child_count for force_resumeTony Lindgren1-0/+1
As pm_runtime_need_not_resume() relies also on usage_count, it can return a different value in pm_runtime_force_suspend() compared to when called in pm_runtime_force_resume(). Different return values can happen if anything calls PM runtime functions in between, and causes the parent child_count to increase on every resume. So far I've seen the issue only for omapdrm that does complicated things with PM runtime calls during system suspend for legacy reasons: omap_atomic_commit_tail() for omapdrm.0 dispc_runtime_get() wakes up 58000000.dss as it's the dispc parent dispc_runtime_resume() rpm_resume() increases parent child_count dispc_runtime_put() won't idle, PM runtime suspend blocked pm_runtime_force_suspend() for 58000000.dss, !pm_runtime_need_not_resume() __update_runtime_status() system suspended pm_runtime_force_resume() for 58000000.dss, pm_runtime_need_not_resume() pm_runtime_enable() only called because of pm_runtime_need_not_resume() omap_atomic_commit_tail() for omapdrm.0 dispc_runtime_get() wakes up 58000000.dss as it's the dispc parent dispc_runtime_resume() rpm_resume() increases parent child_count dispc_runtime_put() won't idle, PM runtime suspend blocked ... rpm_suspend for 58000000.dss but parent child_count is now unbalanced Let's fix the issue by adding a flag for needs_force_resume and use it in pm_runtime_force_resume() instead of pm_runtime_need_not_resume(). Additionally omapdrm system suspend could be simplified later on to avoid lots of unnecessary PM runtime calls and the complexity it adds. The driver can just use internal functions that are shared between the PM runtime and system suspend related functions. Fixes: 4918e1f87c5f ("PM / runtime: Rework pm_runtime_force_suspend/resume()") Signed-off-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Cc: 4.16+ <stable@vger.kernel.org> # 4.16+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-07PM: core: Remove duplicate declaration from header fileWan Jiabing1-1/+0
struct device is declared twice, so remove the duplicate. Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-27PM: clk: make PM clock layer compatible with clocks that must sleepNicolas Pitre1-0/+2
The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-28PM: runtime: Fix timer_expires data type on 32-bit archesGrygorii Strashko1-1/+1
Commit 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") switched PM runtime autosuspend to use hrtimers and all related time accounting in ns, but missed to update the timer_expires data type in struct dev_pm_info to u64. This causes the timer_expires value to be truncated on 32-bit architectures when assignment is done from u64 values: rpm_suspend() |- dev->power.timer_expires = expires; Fix it by changing the timer_expires type to u64. Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Vincent Guittot <vincent.guittot@linaro.org> Cc: 5.0+ <stable@vger.kernel.org> # 5.0+ [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-07-27PM: Make *_DEV_PM_OPS macros use __maybe_unusedPaul Cercueil1-2/+2
This way, when the dev_pm_ops instance is not referenced anywhere, it will simply be dropped by the compiler without a warning. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-07-27PM: core: introduce pm_ptr() macroPaul Cercueil1-0/+6
This macro is analogous to the infamous of_match_ptr(). If CONFIG_PM is enabled, this macro will resolve to its argument, otherwise to NULL. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-24Documentation: PM: sleep: Update driver flags documentationRafael J. Wysocki1-19/+5
Update the documentation of the driver flags for system-wide power management to reflect the current code flows and be more consistent. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-24PM: sleep: core: Rename DPM_FLAG_LEAVE_SUSPENDEDRafael J. Wysocki1-3/+3
Rename DPM_FLAG_LEAVE_SUSPENDED to DPM_FLAG_MAY_SKIP_RESUME which matches its purpose more closely. No functional impact. Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> # for I2C Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24PM: sleep: core: Rename DPM_FLAG_NEVER_SKIPRafael J. Wysocki1-3/+3
Rename DPM_FLAG_NEVER_SKIP to DPM_FLAG_NO_DIRECT_COMPLETE which matches its purpose more closely. No functional impact. Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # for PCI parts Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Alex Deucher <alexander.deucher@amd.com>
2020-04-24PM: sleep: core: Rename dev_pm_smart_suspend_and_suspended()Rafael J. Wysocki1-1/+1
Because all callers of dev_pm_smart_suspend_and_suspended use it only for checking whether or not to skip driver suspend callbacks for a device, rename it to dev_pm_skip_suspend() in analogy with dev_pm_skip_resume(). No functional impact. Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24PM: sleep: core: Rename dev_pm_may_skip_resume()Rafael J. Wysocki1-1/+1
The name of dev_pm_may_skip_resume() may be easily confused with the power.may_skip_resume flag which is not checked by that function, so rename the former as dev_pm_skip_resume(). No functional impact. Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2019-11-13PM / Domains: Introduce dev_pm_domain_start()Ulf Hansson1-0/+2
For a subsystem/driver that either doesn't support runtime PM or makes use of pm_runtime_set_active() during ->probe(), may try to access its device when probing, even if it may not be fully powered on from the PM domain's point of view. This may be the case when the used PM domain is a genpd provider, that implements genpd's ->start|stop() device callbacks. There are cases where the subsystem/driver managed to avoid the above problem, simply by calling pm_runtime_enable() and pm_runtime_get_sync() during ->probe(). However, this approach comes with a drawback, especially if the subsystem/driver implements a ->runtime_resume() callback. More precisely, the subsystem/driver then needs to use a device flag, which is checked in its ->runtime_resume() callback, as to avoid powering on its resources the first time the callback is invoked. This is needed because the subsystem/driver has already powered on the resources for the device, during ->probe() and before it called pm_runtime_get_sync(). In a way to avoid this boilerplate code and the inefficient check for "if (first_time_suspend)" in the ->runtime_resume() callback for these subsystems/drivers, let's introduce and export a dev_pm_domain_start() function, that may be called during ->probe() instead. Moreover, let the dev_pm_domain_start() invoke an optional ->start() callback, added to the struct dev_pm_domain, as to allow a PM domain specific implementation. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-23PM: sleep: Drop dpm_noirq_begin() and dpm_noirq_end()Rafael J. Wysocki1-4/+0
Note that after previous changes dpm_noirq_begin() and dpm_noirq_end() each have only one caller, so move the code from them to their respective callers and drop them. Also note that dpm_noirq_resume_devices() and dpm_noirq_suspend_devices() need not be exported any more, so make them both static. This change is not expected to alter functionality. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de>
2019-07-16Merge tag 'pci-v5.3-changes' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Enumeration changes: - Evaluate PCI Boot Configuration _DSM to learn if firmware wants us to preserve its resource assignments (Benjamin Herrenschmidt) - Simplify resource distribution (Nicholas Johnson) - Decode 32 GT/s link speed (Gustavo Pimentel) Virtualization: - Fix incorrect caching of VF config space size (Alex Williamson) - Fix VF driver probing sysfs knobs (Alex Williamson) Peer-to-peer DMA: - Fix dma_virt_ops check (Logan Gunthorpe) Altera host bridge driver: - Allow building as module (Ley Foon Tan) Armada 8K host bridge driver: - add PHYs support (Miquel Raynal) DesignWare host bridge driver: - Export APIs to support removable loadable module (Vidya Sagar) - Enable Relaxed Ordering erratum workaround only on Tegra20 & Tegra30 (Vidya Sagar) Hyper-V host bridge driver: - Fix use-after-free in eject (Dexuan Cui) Mobiveil host bridge driver: - Clean up and fix many issues, including non-identify mapped windows, 64-bit windows, multi-MSI, class code, INTx clearing (Hou Zhiqiang) Qualcomm host bridge driver: - Use clk bulk API for 2.4.0 controllers (Bjorn Andersson) - Add QCS404 support (Bjorn Andersson) - Assert PERST for at least 100ms (Niklas Cassel) R-Car host bridge driver: - Add r8a774a1 DT support (Biju Das) Tegra host bridge driver: - Add support for Gen2, opportunistic UpdateFC and ACK (PCIe protocol details) AER, GPIO-based PERST# (Manikanta Maddireddy) - Fix many issues, including power-on failure cases, interrupt masking in suspend, UPHY settings, AFI dynamic clock gating, pending DLL transactions (Manikanta Maddireddy) Xilinx host bridge driver: - Fix NWL Multi-MSI programming (Bharat Kumar Gogada) Endpoint support: - Fix 64bit BAR support (Alan Mikhak) - Fix pcitest build issues (Alan Mikhak, Andy Shevchenko) Bug fixes: - Fix NVIDIA GPU multi-function power dependencies (Abhishek Sahu) - Fix NVIDIA GPU HDA enablement issue (Lukas Wunner) - Ignore lockdep for sysfs "remove" (Marek Vasut) Misc: - Convert docs to reST (Changbin Du, Mauro Carvalho Chehab)" * tag 'pci-v5.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (107 commits) PCI: Enable NVIDIA HDA controllers tools: PCI: Fix installation when `make tools/pci_install` PCI: dwc: pci-dra7xx: Fix compilation when !CONFIG_GPIOLIB PCI: Fix typos and whitespace errors PCI: mobiveil: Fix INTx interrupt clearing in mobiveil_pcie_isr() PCI: mobiveil: Fix infinite-loop in the INTx handling function PCI: mobiveil: Move PCIe PIO enablement out of inbound window routine PCI: mobiveil: Add upper 32-bit PCI base address setup in inbound window PCI: mobiveil: Add upper 32-bit CPU base address setup in outbound window PCI: mobiveil: Mask out hardcoded bits in inbound/outbound windows setup PCI: mobiveil: Clear the control fields before updating it PCI: mobiveil: Add configured inbound windows counter PCI: mobiveil: Fix the valid check for inbound and outbound windows PCI: mobiveil: Clean-up program_{ib/ob}_windows() PCI: mobiveil: Remove an unnecessary return value check PCI: mobiveil: Fix error return values PCI: mobiveil: Refactor the MEM/IO outbound window initialization PCI: mobiveil: Make some register updates more readable PCI: mobiveil: Reformat the code for readability dt-bindings: PCI: mobiveil: Change gpio_slave and apb_csr to optional ...
2019-07-04PM: sleep: Drop dev_pm_skip_next_resume_phases()Rafael J. Wysocki1-1/+0
After recent hibernation-related changes, there are no more callers of dev_pm_skip_next_resume_phases() except for the PM core itself in which it is more straightforward to run the statements from that function directly, so do that and drop it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-06-15docs: power: convert docs to ReST and rename to *.rstMauro Carvalho Chehab1-1/+1
Convert the PM documents to ReST, in order to allow them to build with Sphinx. The conversion is actually: - add blank lines and indentation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156Thomas Gleixner1-14/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-07PM-runtime: Call pm_runtime_active|suspended_time() from sysfsUlf Hansson1-1/+0
Avoid the open-coding of the accounted time acquisition in runtime_active|suspend_time_show() and make them call pm_runtime_active|suspended_time() instead. Note that this change also indirectly avoids holding dev->power.lock around the do_div() computation and the sprintf() call which is an additional improvement. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-02-19PM / core: Add support to skip power management in device/driver modelSudeep Holla1-0/+1
All device objects in the driver model contain fields that control the handling of various power management activities. However, it's not always useful. There are few instances where pseudo devices are added to the model just to take advantage of many other features like kobjects, udev events, and so on. One such example is cpu devices and their caches. The sysfs for the cpu caches are managed by adding devices with cpu as the parent in cpu_device_create() when secondary cpu is brought online. Generally when the secondary CPUs are hotplugged back in as part of resume from suspend-to-ram, we call cpu_device_create() from the cpu hotplug state machine while the cpu device associated with that CPU is not yet ready to be resumed as the device_resume() call happens bit later. It's not really needed to set the flag is_prepared for cpu devices as they are mostly pseudo device and hotplug framework deals with state machine and not managed through the cpu device. This often results in annoying warning when resuming: Enabling non-boot CPUs ... CPU1: Booted secondary processor cache: parent cpu1 should not be sleeping CPU1 is up CPU2: Booted secondary processor cache: parent cpu2 should not be sleeping CPU2 is up .... and so on. So in order to fix these kind of errors, we could just completely avoid doing any power management related initialisations and operations if they are not used by these devices. Add no_pm flags to indicate that the device doesn't require any sort of PM activities and all of them can be completely skipped. We can use the same flag to also avoid adding not used *power* sysfs entries for these devices. For now, lets use this for cpu cache devices. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-31PM-runtime: Replace jiffies-based accounting with ktime-based accountingThara Gopinath1-3/+3
Replace jiffies-based accounting for runtime_active_time and runtime_suspended_time with ktime-based accounting. This makes the runtime debug counters inline with genpd and other PM subsytems which use ktime-based accounting. Timekeeping is initialized before driver_init(). It's only at that time that PM-runtime can be enabled. Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org> [switch from ktime to raw nsec] Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-19PM-runtime: Switch autosuspend over to using hrtimersVincent Guittot1-2/+3
PM-runtime uses the timer infrastructure for autosuspend. This implies that the minimum time before autosuspending a device is in the range of 1 tick included to 2 ticks excluded -On arm64 this means between 4ms and 8ms with default jiffies configuration -And on arm, it is between 10ms and 20ms These values are quite high for embedded systems which sometimes want the duration to be in the range of 1 ms. It is possible to switch autosuspend over to using hrtimers to get finer granularity for short durations and take advantage of slack to retain some margins and get long timeouts with minimum wakeups. On an arm64 platform that uses 1ms for autosuspending timeout of its GPU, idle power is reduced by 10% with hrtimer. The latency impact on arm64 hikey octo cores is: - mark_last_busy: from 1.11 us to 1.25 us - rpm_suspend: from 15.54 us to 15.38 us [Only the code path of rpm_suspend() that starts hrtimer has been measured.] arm64 image (arm64 default defconfig) decreases by around 3KB with following details: $ size vmlinux-timer text data bss dec hex filename 12034646 6869268 386840 19290754 1265a82 vmlinux $ size vmlinux-hrtimer text data bss dec hex filename 12030550 6870164 387032 19287746 1264ec2 vmlinux The latency impact on arm 32bits snowball dual cores is : - mark_last_busy: from 0.31 us usec to 0.77 us - rpm_suspend: from 6.83 us to 6.67 usec The increase of the image for snowball platform that I used for testing performance impact, is neglictable (244B). $ size vmlinux-timer text data bss dec hex filename 7157961 2119580 264120 9541661 91981d build-ux500/vmlinux size vmlinux-hrtimer text data bss dec hex filename 7157773 2119884 264248 9541905 919911 vmlinux-hrtimer And arm 32bits image (multi_v7_defconfig) increases by around 1.7KB with following details: $ size vmlinux-timer text data bss dec hex filename 13304443 6803420 402768 20510631 138f7a7 vmlinux $ size vmlinux-hrtimer text data bss dec hex filename 13304299 6805276 402768 20512343 138fe57 vmlinux Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-16Merge back PM core material for v4.16.Rafael J. Wysocki1-4/+12
2017-12-11PM / sleep: Avoid excess pm_runtime_enable() calls in device_resume()Rafael J. Wysocki1-0/+1
Middle-layer code doing suspend-time optimizations for devices with the DPM_FLAG_SMART_SUSPEND flag set (currently, the PCI bus type and the ACPI PM domain) needs to make the core skip ->thaw_early and ->thaw callbacks for those devices in some cases and it sets the power.direct_complete flag for them for this purpose. However, it turns out that setting power.direct_complete outside of the PM core is a bad idea as it triggers an excess invocation of pm_runtime_enable() in device_resume(). For this reason, provide a helper to clear power.is_late_suspended and power.is_suspended to be invoked by the middle-layer code in question instead of setting power.direct_complete and make that code call the new helper. Fixes: c4b65157aeef (PCI / PM: Take SMART_SUSPEND driver flag into account) Fixes: 05087360fd7a (ACPI / PM: Take SMART_SUSPEND driver flag into account) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-27PM / core: Add LEAVE_SUSPENDED driver flagRafael J. Wysocki1-4/+12
Define and document a new driver flag, DPM_FLAG_LEAVE_SUSPENDED, to instruct the PM core and middle-layer (bus type, PM domain, etc.) code that it is desirable to leave the device in runtime suspend after system-wide transitions to the working state (for example, the device may be slow to resume and it may be better to avoid resuming it right away). Generally, the middle-layer code involved in the handling of the device is expected to indicate to the PM core whether or not the device may be left in suspend with the help of the device's power.may_skip_resume status bit. That has to happen in the "noirq" phase of the preceding system suspend (or analogous) transition. The middle layer is then responsible for handling the device as appropriate in its "noirq" resume callback which is executed regardless of whether or not the device may be left suspended, but the other resume callbacks (except for ->complete) will be skipped automatically by the core if the device really can be left in suspend. The additional power.must_resume status bit introduced for the implementation of this mechanisn is used internally by the PM core to track the requirement to resume the device (which may depend on its children etc). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-11-06PCI / PM: Take SMART_SUSPEND driver flag into accountRafael J. Wysocki1-0/+2
Make the PCI bus type take DPM_FLAG_SMART_SUSPEND into account in its system-wide PM callbacks and make sure that all code that should not run in parallel with pci_pm_runtime_resume() is executed in the "late" phases of system suspend, freeze and poweroff transitions. [Note that the pm_runtime_suspended() check in pci_dev_keep_suspended() is an optimization, because if is not passed, all of the subsequent checks may be skipped and some of them are much more overhead in general.] Also use the observation that if the device is in runtime suspend at the beginning of the "late" phase of a system-wide suspend-like transition, its state cannot change going forward (runtime PM is disabled for it at that time) until the transition is over and the subsequent system-wide PM callbacks should be skipped for it (as they generally assume the device to not be suspended), so add checks for that in pci_pm_suspend_late/noirq(), pci_pm_freeze_late/noirq() and pci_pm_poweroff_late/noirq(). Moreover, if pci_pm_resume_noirq() or pci_pm_restore_noirq() is called during the subsequent system-wide resume transition and if the device was left in runtime suspend previously, its runtime PM status needs to be changed to "active" as it is going to be put into the full-power state, so add checks for that too to these functions. In turn, if pci_pm_thaw_noirq() runs after the device has been left in runtime suspend, the subsequent "thaw" callbacks need to be skipped for it (as they may not work correctly with a suspended device), so set the power.direct_complete flag for the device then to make the PM core skip those callbacks. In addition to the above add a core helper for checking if DPM_FLAG_SMART_SUSPEND is set and the device runtime PM status is "suspended" at the same time, which is done quite often in the new code (and will be done elsewhere going forward too). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-06PM / core: Add SMART_SUSPEND driver flagRafael J. Wysocki1-0/+8
Define and document a SMART_SUSPEND flag to instruct bus types and PM domains that the system suspend callbacks provided by the driver can cope with runtime-suspended devices, so from the driver's perspective it should be safe to leave devices in runtime suspend during system suspend. Setting that flag may also cause middle-layer code (bus types, PM domains etc.) to skip invocations of the ->suspend_late and ->suspend_noirq callbacks provided by the driver if the device is in runtime suspend at the beginning of the "late" phase of the system-wide suspend transition, in which case the driver's system-wide resume callbacks may be invoked back-to-back with its ->runtime_suspend callback, so the driver has to be able to cope with that too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-11-06PM / core: Add NEVER_SKIP and SMART_PREPARE driver flagsRafael J. Wysocki1-0/+20
The motivation for this change is to provide a way to work around a problem with the direct-complete mechanism used for avoiding system suspend/resume handling for devices in runtime suspend. The problem is that some middle layer code (the PCI bus type and the ACPI PM domain in particular) returns positive values from its system suspend ->prepare callbacks regardless of whether the driver's ->prepare returns a positive value or 0, which effectively prevents drivers from being able to control the direct-complete feature. Some drivers need that control, however, and the PCI bus type has grown its own flag to deal with this issue, but since it is not limited to PCI, it is better to address it by adding driver flags at the core level. To that end, add a driver_flags field to struct dev_pm_info for flags that can be set by device drivers at the probe time to inform the PM core and/or bus types, PM domains and so on on the capabilities and/or preferences of device drivers. Also add two static inline helpers for setting that field and testing it against a given set of flags and make the driver core clear it automatically on driver remove and probe failures. Define and document two PM driver flags related to the direct- complete feature: NEVER_SKIP and SMART_PREPARE that can be used, respectively, to indicate to the PM core that the direct-complete mechanism should never be used for the device and to inform the middle layer code (bus types, PM domains etc) that it can only request the PM core to use the direct-complete mechanism for the device (by returning a positive value from its ->prepare callback) if it also has been requested by the driver. While at it, make the core check pm_runtime_suspended() when setting power.direct_complete so that it doesn't need to be checked by ->prepare callbacks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>