pmufreq.c revision 285830
1/*- 2 * Copyright (c) 2011 Justin Hibbits 3 * Copyright (c) 2009 Nathan Whitehorn 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 20 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 21 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 22 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD: releng/10.2/sys/powerpc/cpufreq/pmufreq.c 260674 2014-01-15 06:17:15Z jhibbits $"); 30 31#include <sys/param.h> 32#include <sys/systm.h> 33#include <sys/bus.h> 34#include <sys/cpu.h> 35#include <sys/kernel.h> 36#include <sys/limits.h> 37#include <sys/module.h> 38 39#include <dev/ofw/ofw_bus.h> 40#include <dev/ofw/openfirm.h> 41 42#include "cpufreq_if.h" 43#include "powerpc/powermac/pmuvar.h" 44 45struct pmufreq_softc { 46 device_t dev; 47 uint32_t minfreq; 48 uint32_t maxfreq; 49 uint32_t curfreq; 50}; 51 52static void pmufreq_identify(driver_t *driver, device_t parent); 53static int pmufreq_probe(device_t dev); 54static int pmufreq_attach(device_t dev); 55static int pmufreq_settings(device_t dev, struct cf_setting *sets, int *count); 56static int pmufreq_set(device_t dev, const struct cf_setting *set); 57static int pmufreq_get(device_t dev, struct cf_setting *set); 58static int pmufreq_type(device_t dev, int *type); 59 60static device_method_t pmufreq_methods[] = { 61 /* Device interface */ 62 DEVMETHOD(device_identify, pmufreq_identify), 63 DEVMETHOD(device_probe, pmufreq_probe), 64 DEVMETHOD(device_attach, pmufreq_attach), 65 66 /* cpufreq interface */ 67 DEVMETHOD(cpufreq_drv_set, pmufreq_set), 68 DEVMETHOD(cpufreq_drv_get, pmufreq_get), 69 DEVMETHOD(cpufreq_drv_type, pmufreq_type), 70 DEVMETHOD(cpufreq_drv_settings, pmufreq_settings), 71 72 {0, 0} 73}; 74 75static driver_t pmufreq_driver = { 76 "pmufreq", 77 pmufreq_methods, 78 sizeof(struct pmufreq_softc) 79}; 80 81static devclass_t pmufreq_devclass; 82DRIVER_MODULE(pmufreq, cpu, pmufreq_driver, pmufreq_devclass, 0, 0); 83 84static void 85pmufreq_identify(driver_t *driver, device_t parent) 86{ 87 phandle_t node; 88 uint32_t min_freq; 89 90 node = ofw_bus_get_node(parent); 91 if (OF_getprop(node, "min-clock-frequency", &min_freq, sizeof(min_freq)) == -1) 92 return; 93 94 /* Make sure we're not being doubly invoked. */ 95 if (device_find_child(parent, "pmufreq", -1) != NULL) 96 return; 97 98 /* 99 * We attach a child for every CPU since settings need to 100 * be performed on every CPU in the SMP case. 101 */ 102 if (BUS_ADD_CHILD(parent, 10, "pmufreq", -1) == NULL) 103 device_printf(parent, "add pmufreq child failed\n"); 104} 105 106static int 107pmufreq_probe(device_t dev) 108{ 109 struct pmufreq_softc *sc; 110 phandle_t node; 111 uint32_t min_freq; 112 113 if (resource_disabled("pmufreq", 0)) 114 return (ENXIO); 115 116 sc = device_get_softc(dev); 117 node = ofw_bus_get_node(device_get_parent(dev)); 118 /* 119 * A scalable MPC7455 has min-clock-frequency/max-clock-frequency as OFW 120 * properties of the 'cpu' node. 121 */ 122 if (OF_getprop(node, "min-clock-frequency", &min_freq, sizeof(min_freq)) == -1) 123 return (ENXIO); 124 device_set_desc(dev, "PMU-based frequency scaling"); 125 return (0); 126} 127 128static int 129pmufreq_attach(device_t dev) 130{ 131 struct pmufreq_softc *sc; 132 phandle_t node; 133 134 sc = device_get_softc(dev); 135 sc->dev = dev; 136 137 node = ofw_bus_get_node(device_get_parent(dev)); 138 OF_getprop(node, "min-clock-frequency", &sc->minfreq, sizeof(sc->minfreq)); 139 OF_getprop(node, "max-clock-frequency", &sc->maxfreq, sizeof(sc->maxfreq)); 140 OF_getprop(node, "rounded-clock-frequency", &sc->curfreq, sizeof(sc->curfreq)); 141 sc->minfreq /= 1000000; 142 sc->maxfreq /= 1000000; 143 sc->curfreq /= 1000000; 144 145 cpufreq_register(dev); 146 return (0); 147} 148 149static int 150pmufreq_settings(device_t dev, struct cf_setting *sets, int *count) 151{ 152 struct pmufreq_softc *sc; 153 154 sc = device_get_softc(dev); 155 if (sets == NULL || count == NULL) 156 return (EINVAL); 157 if (*count < 2) 158 return (E2BIG); 159 160 /* Return a list of valid settings for this driver. */ 161 memset(sets, CPUFREQ_VAL_UNKNOWN, sizeof(*sets) * 2); 162 163 sets[0].freq = sc->maxfreq; sets[0].dev = dev; 164 sets[1].freq = sc->minfreq; sets[1].dev = dev; 165 /* Set high latency for CPU frequency changes, it's a tedious process. */ 166 sets[0].lat = INT_MAX; 167 sets[1].lat = INT_MAX; 168 *count = 2; 169 170 return (0); 171} 172 173static int 174pmufreq_set(device_t dev, const struct cf_setting *set) 175{ 176 struct pmufreq_softc *sc; 177 int error, speed_sel; 178 179 if (set == NULL) 180 return (EINVAL); 181 182 sc = device_get_softc(dev); 183 184 if (set->freq == sc->maxfreq) 185 speed_sel = 0; 186 else 187 speed_sel = 1; 188 189 error = pmu_set_speed(speed_sel); 190 if (error == 0) 191 sc->curfreq = set->freq; 192 193 return (error); 194} 195 196static int 197pmufreq_get(device_t dev, struct cf_setting *set) 198{ 199 struct pmufreq_softc *sc; 200 201 if (set == NULL) 202 return (EINVAL); 203 sc = device_get_softc(dev); 204 205 set->freq = sc->curfreq; 206 set->dev = dev; 207 208 return (0); 209} 210 211static int 212pmufreq_type(device_t dev, int *type) 213{ 214 215 if (type == NULL) 216 return (EINVAL); 217 218 *type = CPUFREQ_TYPE_ABSOLUTE; 219 return (0); 220} 221 222