1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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/param.h> 31 #include <sys/systm.h> 32 #include <sys/bus.h> 33 #include <sys/cpu.h> 34 #include <sys/kernel.h> 35 #include <sys/limits.h> 36 #include <sys/module.h> 37 38 #include <dev/ofw/ofw_bus.h> 39 #include <dev/ofw/openfirm.h> 40 41 #include "cpufreq_if.h" 42 #include "powerpc/powermac/pmuvar.h" 43 44 struct pmufreq_softc { 45 device_t dev; 46 uint32_t minfreq; 47 uint32_t maxfreq; 48 uint32_t curfreq; 49 }; 50 51 static void pmufreq_identify(driver_t *driver, device_t parent); 52 static int pmufreq_probe(device_t dev); 53 static int pmufreq_attach(device_t dev); 54 static int pmufreq_settings(device_t dev, struct cf_setting *sets, int *count); 55 static int pmufreq_set(device_t dev, const struct cf_setting *set); 56 static int pmufreq_get(device_t dev, struct cf_setting *set); 57 static int pmufreq_type(device_t dev, int *type); 58 59 static device_method_t pmufreq_methods[] = { 60 /* Device interface */ 61 DEVMETHOD(device_identify, pmufreq_identify), 62 DEVMETHOD(device_probe, pmufreq_probe), 63 DEVMETHOD(device_attach, pmufreq_attach), 64 65 /* cpufreq interface */ 66 DEVMETHOD(cpufreq_drv_set, pmufreq_set), 67 DEVMETHOD(cpufreq_drv_get, pmufreq_get), 68 DEVMETHOD(cpufreq_drv_type, pmufreq_type), 69 DEVMETHOD(cpufreq_drv_settings, pmufreq_settings), 70 {0, 0} 71 }; 72 73 static driver_t pmufreq_driver = { 74 "pmufreq", 75 pmufreq_methods, 76 sizeof(struct pmufreq_softc) 77 }; 78 79 DRIVER_MODULE(pmufreq, cpu, pmufreq_driver, 0, 0); 80 81 static void 82 pmufreq_identify(driver_t *driver, device_t parent) 83 { 84 phandle_t node; 85 uint32_t min_freq; 86 87 node = ofw_bus_get_node(parent); 88 if (OF_getprop(node, "min-clock-frequency", &min_freq, sizeof(min_freq)) == -1) 89 return; 90 91 /* Make sure we're not being doubly invoked. */ 92 if (device_find_child(parent, "pmufreq", -1) != NULL) 93 return; 94 95 /* 96 * We attach a child for every CPU since settings need to 97 * be performed on every CPU in the SMP case. 98 */ 99 if (BUS_ADD_CHILD(parent, 10, "pmufreq", -1) == NULL) 100 device_printf(parent, "add pmufreq child failed\n"); 101 } 102 103 static int 104 pmufreq_probe(device_t dev) 105 { 106 phandle_t node; 107 uint32_t min_freq; 108 109 if (resource_disabled("pmufreq", 0)) 110 return (ENXIO); 111 112 node = ofw_bus_get_node(device_get_parent(dev)); 113 /* 114 * A scalable MPC7455 has min-clock-frequency/max-clock-frequency as OFW 115 * properties of the 'cpu' node. 116 */ 117 if (OF_getprop(node, "min-clock-frequency", &min_freq, sizeof(min_freq)) == -1) 118 return (ENXIO); 119 device_set_desc(dev, "PMU-based frequency scaling"); 120 return (0); 121 } 122 123 static int 124 pmufreq_attach(device_t dev) 125 { 126 struct pmufreq_softc *sc; 127 phandle_t node; 128 129 sc = device_get_softc(dev); 130 sc->dev = dev; 131 132 node = ofw_bus_get_node(device_get_parent(dev)); 133 OF_getprop(node, "min-clock-frequency", &sc->minfreq, sizeof(sc->minfreq)); 134 OF_getprop(node, "max-clock-frequency", &sc->maxfreq, sizeof(sc->maxfreq)); 135 OF_getprop(node, "rounded-clock-frequency", &sc->curfreq, sizeof(sc->curfreq)); 136 sc->minfreq /= 1000000; 137 sc->maxfreq /= 1000000; 138 sc->curfreq /= 1000000; 139 140 cpufreq_register(dev); 141 return (0); 142 } 143 144 static int 145 pmufreq_settings(device_t dev, struct cf_setting *sets, int *count) 146 { 147 struct pmufreq_softc *sc; 148 149 sc = device_get_softc(dev); 150 if (sets == NULL || count == NULL) 151 return (EINVAL); 152 if (*count < 2) 153 return (E2BIG); 154 155 /* Return a list of valid settings for this driver. */ 156 memset(sets, CPUFREQ_VAL_UNKNOWN, sizeof(*sets) * 2); 157 158 sets[0].freq = sc->maxfreq; sets[0].dev = dev; 159 sets[1].freq = sc->minfreq; sets[1].dev = dev; 160 /* Set high latency for CPU frequency changes, it's a tedious process. */ 161 sets[0].lat = INT_MAX; 162 sets[1].lat = INT_MAX; 163 *count = 2; 164 165 return (0); 166 } 167 168 static int 169 pmufreq_set(device_t dev, const struct cf_setting *set) 170 { 171 struct pmufreq_softc *sc; 172 int error, speed_sel; 173 174 if (set == NULL) 175 return (EINVAL); 176 177 sc = device_get_softc(dev); 178 179 if (set->freq == sc->maxfreq) 180 speed_sel = 0; 181 else 182 speed_sel = 1; 183 184 error = pmu_set_speed(speed_sel); 185 if (error == 0) 186 sc->curfreq = set->freq; 187 188 return (error); 189 } 190 191 static int 192 pmufreq_get(device_t dev, struct cf_setting *set) 193 { 194 struct pmufreq_softc *sc; 195 196 if (set == NULL) 197 return (EINVAL); 198 sc = device_get_softc(dev); 199 200 set->freq = sc->curfreq; 201 set->dev = dev; 202 203 return (0); 204 } 205 206 static int 207 pmufreq_type(device_t dev, int *type) 208 { 209 210 if (type == NULL) 211 return (EINVAL); 212 213 *type = CPUFREQ_TYPE_ABSOLUTE; 214 return (0); 215 } 216