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