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linux/drivers/thermal/intel/intel_hfi.h
Ricardo Neri ab09b0744a thermal: intel: hfi: Enable notification interrupt
When hardware wants to inform the operating system about updates in the HFI
table, it issues a package-level thermal event interrupt. For this,
hardware has new interrupt and status bits in the IA32_PACKAGE_THERM_
INTERRUPT and IA32_PACKAGE_THERM_STATUS registers. The existing thermal
throttle driver already handles thermal event interrupts: it initializes
the thermal vector of the local APIC as well as per-CPU and package-level
interrupt reporting. It also provides routines to service such interrupts.
Extend its functionality to also handle HFI interrupts.

The frequency of the thermal HFI interrupt is specific to each processor
model. On some processors, a single interrupt happens as soon as the HFI is
enabled and hardware will never update HFI capabilities afterwards. On
other processors, thermal and power constraints may cause thermal HFI
interrupts every tens of milliseconds.

To not overwhelm consumers of the HFI data, use delayed work to throttle
the rate at which HFI updates are processed. Use a dedicated workqueue to
not overload system_wq if hardware issues many HFI updates.

Reviewed-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-02-03 19:50:49 +01:00

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610 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _INTEL_HFI_H
#define _INTEL_HFI_H
#if defined(CONFIG_INTEL_HFI_THERMAL)
void __init intel_hfi_init(void);
void intel_hfi_online(unsigned int cpu);
void intel_hfi_offline(unsigned int cpu);
void intel_hfi_process_event(__u64 pkg_therm_status_msr_val);
#else
static inline void intel_hfi_init(void) { }
static inline void intel_hfi_online(unsigned int cpu) { }
static inline void intel_hfi_offline(unsigned int cpu) { }
static inline void intel_hfi_process_event(__u64 pkg_therm_status_msr_val) { }
#endif /* CONFIG_INTEL_HFI_THERMAL */
#endif /* _INTEL_HFI_H */