cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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cpu_pm.h (2433B)

      1/* SPDX-License-Identifier: GPL-2.0-only */
      2/*
      3 * Copyright (C) 2011 Google, Inc.
      4 *
      5 * Author:
      6 *	Colin Cross <ccross@android.com>
      7 */
      8
      9#ifndef _LINUX_CPU_PM_H
     10#define _LINUX_CPU_PM_H
     11
     12#include <linux/kernel.h>
     13#include <linux/notifier.h>
     14
     15/*
     16 * When a CPU goes to a low power state that turns off power to the CPU's
     17 * power domain, the contents of some blocks (floating point coprocessors,
     18 * interrupt controllers, caches, timers) in the same power domain can
     19 * be lost.  The cpm_pm notifiers provide a method for platform idle, suspend,
     20 * and hotplug implementations to notify the drivers for these blocks that
     21 * they may be reset.
     22 *
     23 * All cpu_pm notifications must be called with interrupts disabled.
     24 *
     25 * The notifications are split into two classes: CPU notifications and CPU
     26 * cluster notifications.
     27 *
     28 * CPU notifications apply to a single CPU and must be called on the affected
     29 * CPU.  They are used to save per-cpu context for affected blocks.
     30 *
     31 * CPU cluster notifications apply to all CPUs in a single power domain. They
     32 * are used to save any global context for affected blocks, and must be called
     33 * after all the CPUs in the power domain have been notified of the low power
     34 * state.
     35 */
     36
     37/*
     38 * Event codes passed as unsigned long val to notifier calls
     39 */
     40enum cpu_pm_event {
     41	/* A single cpu is entering a low power state */
     42	CPU_PM_ENTER,
     43
     44	/* A single cpu failed to enter a low power state */
     45	CPU_PM_ENTER_FAILED,
     46
     47	/* A single cpu is exiting a low power state */
     48	CPU_PM_EXIT,
     49
     50	/* A cpu power domain is entering a low power state */
     51	CPU_CLUSTER_PM_ENTER,
     52
     53	/* A cpu power domain failed to enter a low power state */
     54	CPU_CLUSTER_PM_ENTER_FAILED,
     55
     56	/* A cpu power domain is exiting a low power state */
     57	CPU_CLUSTER_PM_EXIT,
     58};
     59
     60#ifdef CONFIG_CPU_PM
     61int cpu_pm_register_notifier(struct notifier_block *nb);
     62int cpu_pm_unregister_notifier(struct notifier_block *nb);
     63int cpu_pm_enter(void);
     64int cpu_pm_exit(void);
     65int cpu_cluster_pm_enter(void);
     66int cpu_cluster_pm_exit(void);
     67
     68#else
     69
     70static inline int cpu_pm_register_notifier(struct notifier_block *nb)
     71{
     72	return 0;
     73}
     74
     75static inline int cpu_pm_unregister_notifier(struct notifier_block *nb)
     76{
     77	return 0;
     78}
     79
     80static inline int cpu_pm_enter(void)
     81{
     82	return 0;
     83}
     84
     85static inline int cpu_pm_exit(void)
     86{
     87	return 0;
     88}
     89
     90static inline int cpu_cluster_pm_enter(void)
     91{
     92	return 0;
     93}
     94
     95static inline int cpu_cluster_pm_exit(void)
     96{
     97	return 0;
     98}
     99#endif
    100#endif