1/*- 2 * Copyright (c) 2005-2007 Nate Lawson (SDG) 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29#ifndef _SYS_CPU_H_ 30#define _SYS_CPU_H_ 31 32#include <sys/eventhandler.h> 33 34/* 35 * CPU device support. 36 */ 37 38#define CPU_IVAR_PCPU 1 39#define CPU_IVAR_NOMINAL_MHZ 2 40 41static __inline struct pcpu *cpu_get_pcpu(device_t dev) 42{ 43 uintptr_t v = 0; 44 BUS_READ_IVAR(device_get_parent(dev), dev, CPU_IVAR_PCPU, &v); 45 return ((struct pcpu *)v); 46} 47 48static __inline int32_t cpu_get_nominal_mhz(device_t dev) 49{ 50 uintptr_t v = 0; 51 if (BUS_READ_IVAR(device_get_parent(dev), dev, 52 CPU_IVAR_NOMINAL_MHZ, &v) != 0) 53 return (-1); 54 return ((int32_t)v); 55} 56 57/* 58 * CPU frequency control interface. 59 */ 60 61/* Each driver's CPU frequency setting is exported in this format. */ 62struct cf_setting { 63 int freq; /* CPU clock in Mhz or 100ths of a percent. */ 64 int volts; /* Voltage in mV. */ 65 int power; /* Power consumed in mW. */ 66 int lat; /* Transition latency in us. */ 67 device_t dev; /* Driver providing this setting. */ 68 int spec[4];/* Driver-specific storage for non-standard info. */ 69}; 70 71/* Maximum number of settings a given driver can have. */ 72#define MAX_SETTINGS 24 73 74/* A combination of settings is a level. */ 75struct cf_level { 76 struct cf_setting total_set; 77 struct cf_setting abs_set; 78 struct cf_setting rel_set[MAX_SETTINGS]; 79 int rel_count; 80 TAILQ_ENTRY(cf_level) link; 81}; 82 83TAILQ_HEAD(cf_level_lst, cf_level); 84 85/* Drivers should set all unknown values to this. */ 86#define CPUFREQ_VAL_UNKNOWN (-1) 87 88/* 89 * Every driver offers a type of CPU control. Absolute levels are mutually 90 * exclusive while relative levels modify the current absolute level. There 91 * may be multiple absolute and relative drivers available on a given 92 * system. 93 * 94 * For example, consider a system with two absolute drivers that provide 95 * frequency settings of 100, 200 and 300, 400 and a relative driver that 96 * provides settings of 50%, 100%. The cpufreq core would export frequency 97 * levels of 50, 100, 150, 200, 300, 400. 98 * 99 * The "info only" flag signifies that settings returned by 100 * CPUFREQ_DRV_SETTINGS cannot be passed to the CPUFREQ_DRV_SET method and 101 * are only informational. This is for some drivers that can return 102 * information about settings but rely on another machine-dependent driver 103 * for actually performing the frequency transition (e.g., ACPI performance 104 * states of type "functional fixed hardware.") 105 */ 106#define CPUFREQ_TYPE_MASK 0xffff 107#define CPUFREQ_TYPE_RELATIVE (1<<0) 108#define CPUFREQ_TYPE_ABSOLUTE (1<<1) 109#define CPUFREQ_FLAG_INFO_ONLY (1<<16) 110 111/* 112 * When setting a level, the caller indicates the priority of this request. 113 * Priorities determine, among other things, whether a level can be 114 * overridden by other callers. For example, if the user sets a level but 115 * the system thermal driver needs to override it for emergency cooling, 116 * the driver would use a higher priority. Once the event has passed, the 117 * driver would call cpufreq to resume any previous level. 118 */ 119#define CPUFREQ_PRIO_HIGHEST 1000000 120#define CPUFREQ_PRIO_KERN 1000 121#define CPUFREQ_PRIO_USER 100 122#define CPUFREQ_PRIO_LOWEST 0 123 124/* 125 * Register and unregister a driver with the cpufreq core. Once a driver 126 * is registered, it must support calls to its CPUFREQ_GET, CPUFREQ_GET_LEVEL, 127 * and CPUFREQ_SET methods. It must also unregister before returning from 128 * its DEVICE_DETACH method. 129 */ 130int cpufreq_register(device_t dev); 131int cpufreq_unregister(device_t dev); 132 133/* 134 * Notify the cpufreq core that the number of or values for settings have 135 * changed. 136 */ 137int cpufreq_settings_changed(device_t dev); 138 139/* 140 * Eventhandlers that are called before and after a change in frequency. 141 * The new level and the result of the change (0 is success) is passed in. 142 * If the driver wishes to revoke the change from cpufreq_pre_change, it 143 * stores a non-zero error code in the result parameter and the change will 144 * not be made. If the post-change eventhandler gets a non-zero result, 145 * no change was made and the previous level remains in effect. If a change 146 * is revoked, the post-change eventhandler is still called with the error 147 * value supplied by the revoking driver. This gives listeners who cached 148 * some data in preparation for a level change a chance to clean up. 149 */ 150typedef void (*cpufreq_pre_notify_fn)(void *, const struct cf_level *, int *); 151typedef void (*cpufreq_post_notify_fn)(void *, const struct cf_level *, int); 152EVENTHANDLER_DECLARE(cpufreq_pre_change, cpufreq_pre_notify_fn); 153EVENTHANDLER_DECLARE(cpufreq_post_change, cpufreq_post_notify_fn); 154 155/* 156 * Eventhandler called when the available list of levels changed. 157 * The unit number of the device (i.e. "cpufreq0") whose levels changed 158 * is provided so the listener can retrieve the new list of levels. 159 */ 160typedef void (*cpufreq_levels_notify_fn)(void *, int); 161EVENTHANDLER_DECLARE(cpufreq_levels_changed, cpufreq_levels_notify_fn); 162 163/* Allow values to be +/- a bit since sometimes we have to estimate. */ 164#define CPUFREQ_CMP(x, y) (abs((x) - (y)) < 25) 165 166/* 167 * Machine-dependent functions. 168 */ 169 170/* Estimate the current clock rate for the given CPU id. */ 171int cpu_est_clockrate(int cpu_id, uint64_t *rate); 172 173#endif /* !_SYS_CPU_H_ */ 174