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2023-10-12thermal: int340x: processor_thermal: Support power floor notificationsSrinivas Pandruvada1-0/+10
When the hardware reduces the power to the minimum possible, the power floor is notified via an interrupt. This can happen when user space requests a power limit via powercap RAPL interface, which forces the system to enter to the lowest power. This power floor indication can be used as a hint to resort to other methods of reducing power than via RAPL power limit. Before power floor status can be read or the firmware can trigger notifications regarding it, it needs to be configured via a mailbox command. The actual power floor status is read via bit 39 of MMIO offset 0x5B18 of the processor thermal PCI device. To show the current power floor status and get notification on a sysfs attribute, add 2 new attributes to /sys/bus/pci/devices/0000\:00\:04.0/power_limits/ power_floor_enable : This attribute is present when power floor notifications are supported. This attribute allows to enable/disable power floor notifications. power_floor_status : This attribute is present when power floor notifications are supported. When enabled via power_floor_enable, this attribute shows the current power floor status. The power floor implementation provides interfaces which are called from the sysfs callbacks to enable/disable and read power floor status. It also provides two additional interfaces to check if the current processor thermal device interrupt is for power floor status and to send notifications to user space. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [ rjw: Changelog and documentation changes edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-09-14thermal: int340x: processor_thermal: Add workload type hint interfaceSrinivas Pandruvada1-0/+54
Prior to Meteor Lake processor generation, user space can pass workload type request to the firmware. Then firmware can optimize power based on the indicated workload type. User space also uses workload type requests to implement its own heuristics. The firmware in Meteor Lake processor generation is capable of predicting workload type without software help. To avoid duplicate processing, add a sysfs interface allowing user space to obtain the workload hint from the firmware instead of trying to predict the workload type by itself. This workload hint is passed from the firmware via MMIO offset 0x5B18 of the processor thermal PCI device. Before workload hints can be produced by the firmware, it needs to be configured via a mailbox command. This mailbox command turns ON the workload hint and it allows to program a notification delay to control the rate of notifications. The notification delay can be changed from user space vis sysfs. Attribute group 'workload_hint' in sysfs is used for implementing the workload hints interface between user space and the kernel. It contains the following attributes: workload_type_enable: Enables/disables workload type hints from the firmware. notification_delay_ms: Notification delay in milliseconds. workload_type_index: The current workload type index predicted by the firmware (see the documentation changes below for supported index values and their meaning). Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [ rjw: Changelog edits, documentation edits, whitespace adjustments ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-04-18thermal: intel: int340x: Add DLVR support for RFIM controlSrinivas Pandruvada1-2/+44
Add support for DLVR (Digital Linear Voltage Regulator) attributes, which can be used to control RFIM. Here instead of "fivr" another directory "dlvr" is created with DLVR attributes: /sys/bus/pci/devices/0000:00:04.0/dlvr ├── dlvr_freq_mhz ├── dlvr_freq_select ├── dlvr_hardware_rev ├── dlvr_pll_busy ├── dlvr_rfim_enable └── dlvr_spread_spectrum_pct └── dlvr_control_mode └── dlvr_control_lock Attributes dlvr_freq_mhz (RO): Current DLVR PLL frequency in MHz. dlvr_freq_select (RW): Sets DLVR PLL clock frequency. dlvr_hardware_rev (RO): DLVR hardware revision. dlvr_pll_busy (RO): PLL can't accept frequency change when set. dlvr_rfim_enable (RW): 0: Disable RF frequency hopping, 1: Enable RF frequency hopping. dlvr_control_mode (RW): Specifies how frequencies are spread. 0: Down spread, 1: Spread in Center. dlvr_control_lock (RW): 1: future writes are ignored. dlvr_spread_spectrum_pct (RW) A write to this register updates the DLVR spread spectrum percent value. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-01-26thermal: intel: int340x: Add production mode attributeSrinivas Pandruvada1-0/+3
It is possible that the system manufacturer locks down thermal tuning beyond what is usually done on the given platform. In that case user space calibration tools should not try to adjust the thermal configuration of the system. To allow user space to check if that is the case, add a new sysfs attribute "production_mode" that will be present when the ACPI DCFG method is present under the INT3400 device object in the ACPI Namespace. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-05docs: driver-api/thermal/intel_dptf: Use copyright symbolAkira Yokosawa1-1/+1
Using a substitution pattern of "|copy|" without including isonum.txt causes a doc build warning. Using the symbol "©" itself is a better choice for those who read .rst sources. Reported by: Randy Dunlap <rdunlap@infradead.org> Fixes: 16c02447f3e1 ("Documentation: thermal: DPTF Documentation") Suggested-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: linux-pm@vger.kernel.org Cc: linux-doc@vger.kernel.org Acked-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-03-16Documentation: thermal: DPTF DocumentationSrinivas Pandruvada1-0/+272
Document Intel Dynamic Platform and Thermal Framework (DPTF) ABI. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>