1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2005-2007 Nate Lawson (SDG) 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #ifndef _SYS_CPU_H_ 32 #define _SYS_CPU_H_ 33 34 #include <sys/eventhandler.h> 35 36 /* 37 * CPU device support. 38 */ 39 40 #define CPU_IVAR_PCPU 1 41 #define CPU_IVAR_NOMINAL_MHZ 2 42 #define CPU_IVAR_CPUID_SIZE 3 43 #define CPU_IVAR_CPUID 4 44 45 static __inline struct pcpu *cpu_get_pcpu(device_t dev) 46 { 47 uintptr_t v = 0; 48 BUS_READ_IVAR(device_get_parent(dev), dev, CPU_IVAR_PCPU, &v); 49 return ((struct pcpu *)v); 50 } 51 52 static __inline int32_t cpu_get_nominal_mhz(device_t dev) 53 { 54 uintptr_t v = 0; 55 if (BUS_READ_IVAR(device_get_parent(dev), dev, 56 CPU_IVAR_NOMINAL_MHZ, &v) != 0) 57 return (-1); 58 return ((int32_t)v); 59 } 60 61 static __inline const uint32_t *cpu_get_cpuid(device_t dev, size_t *count) 62 { 63 uintptr_t v = 0; 64 if (BUS_READ_IVAR(device_get_parent(dev), dev, 65 CPU_IVAR_CPUID_SIZE, &v) != 0) 66 return (NULL); 67 *count = (size_t)v; 68 69 if (BUS_READ_IVAR(device_get_parent(dev), dev, 70 CPU_IVAR_CPUID, &v) != 0) 71 return (NULL); 72 return ((const uint32_t *)v); 73 } 74 75 /* 76 * CPU frequency control interface. 77 */ 78 79 /* Each driver's CPU frequency setting is exported in this format. */ 80 struct cf_setting { 81 int freq; /* CPU clock in Mhz or 100ths of a percent. */ 82 int volts; /* Voltage in mV. */ 83 int power; /* Power consumed in mW. */ 84 int lat; /* Transition latency in us. */ 85 device_t dev; /* Driver providing this setting. */ 86 int spec[4];/* Driver-specific storage for non-standard info. */ 87 }; 88 89 /* Maximum number of settings a given driver can have. */ 90 #define MAX_SETTINGS 24 91 92 /* A combination of settings is a level. */ 93 struct cf_level { 94 struct cf_setting total_set; 95 struct cf_setting abs_set; 96 struct cf_setting rel_set[MAX_SETTINGS]; 97 int rel_count; 98 TAILQ_ENTRY(cf_level) link; 99 }; 100 101 TAILQ_HEAD(cf_level_lst, cf_level); 102 103 /* Drivers should set all unknown values to this. */ 104 #define CPUFREQ_VAL_UNKNOWN (-1) 105 106 /* 107 * Every driver offers a type of CPU control. Absolute levels are mutually 108 * exclusive while relative levels modify the current absolute level. There 109 * may be multiple absolute and relative drivers available on a given 110 * system. 111 * 112 * For example, consider a system with two absolute drivers that provide 113 * frequency settings of 100, 200 and 300, 400 and a relative driver that 114 * provides settings of 50%, 100%. The cpufreq core would export frequency 115 * levels of 50, 100, 150, 200, 300, 400. 116 * 117 * The "info only" flag signifies that settings returned by 118 * CPUFREQ_DRV_SETTINGS cannot be passed to the CPUFREQ_DRV_SET method and 119 * are only informational. This is for some drivers that can return 120 * information about settings but rely on another machine-dependent driver 121 * for actually performing the frequency transition (e.g., ACPI performance 122 * states of type "functional fixed hardware.") 123 */ 124 #define CPUFREQ_TYPE_MASK 0xffff 125 #define CPUFREQ_TYPE_RELATIVE (1<<0) 126 #define CPUFREQ_TYPE_ABSOLUTE (1<<1) 127 #define CPUFREQ_FLAG_INFO_ONLY (1<<16) 128 129 /* 130 * When setting a level, the caller indicates the priority of this request. 131 * Priorities determine, among other things, whether a level can be 132 * overridden by other callers. For example, if the user sets a level but 133 * the system thermal driver needs to override it for emergency cooling, 134 * the driver would use a higher priority. Once the event has passed, the 135 * driver would call cpufreq to resume any previous level. 136 */ 137 #define CPUFREQ_PRIO_HIGHEST 1000000 138 #define CPUFREQ_PRIO_KERN 1000 139 #define CPUFREQ_PRIO_USER 100 140 #define CPUFREQ_PRIO_LOWEST 0 141 142 /* 143 * Register and unregister a driver with the cpufreq core. Once a driver 144 * is registered, it must support calls to its CPUFREQ_GET, CPUFREQ_GET_LEVEL, 145 * and CPUFREQ_SET methods. It must also unregister before returning from 146 * its DEVICE_DETACH method. 147 */ 148 int cpufreq_register(device_t dev); 149 int cpufreq_unregister(device_t dev); 150 151 /* 152 * Notify the cpufreq core that the number of or values for settings have 153 * changed. 154 */ 155 int cpufreq_settings_changed(device_t dev); 156 157 /* 158 * Eventhandlers that are called before and after a change in frequency. 159 * The new level and the result of the change (0 is success) is passed in. 160 * If the driver wishes to revoke the change from cpufreq_pre_change, it 161 * stores a non-zero error code in the result parameter and the change will 162 * not be made. If the post-change eventhandler gets a non-zero result, 163 * no change was made and the previous level remains in effect. If a change 164 * is revoked, the post-change eventhandler is still called with the error 165 * value supplied by the revoking driver. This gives listeners who cached 166 * some data in preparation for a level change a chance to clean up. 167 */ 168 typedef void (*cpufreq_pre_notify_fn)(void *, const struct cf_level *, int *); 169 typedef void (*cpufreq_post_notify_fn)(void *, const struct cf_level *, int); 170 EVENTHANDLER_DECLARE(cpufreq_pre_change, cpufreq_pre_notify_fn); 171 EVENTHANDLER_DECLARE(cpufreq_post_change, cpufreq_post_notify_fn); 172 173 /* 174 * Eventhandler called when the available list of levels changed. 175 * The unit number of the device (i.e. "cpufreq0") whose levels changed 176 * is provided so the listener can retrieve the new list of levels. 177 */ 178 typedef void (*cpufreq_levels_notify_fn)(void *, int); 179 EVENTHANDLER_DECLARE(cpufreq_levels_changed, cpufreq_levels_notify_fn); 180 181 /* Allow values to be +/- a bit since sometimes we have to estimate. */ 182 #define CPUFREQ_CMP(x, y) (abs((x) - (y)) < 25) 183 184 /* 185 * Machine-dependent functions. 186 */ 187 188 /* Estimate the current clock rate for the given CPU id. */ 189 int cpu_est_clockrate(int cpu_id, uint64_t *rate); 190 191 #endif /* !_SYS_CPU_H_ */ 192