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/cdefs.h> 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 45 struct pmufreq_softc { 46 device_t dev; 47 uint32_t minfreq; 48 uint32_t maxfreq; 49 uint32_t curfreq; 50 }; 51 52 static void pmufreq_identify(driver_t *driver, device_t parent); 53 static int pmufreq_probe(device_t dev); 54 static int pmufreq_attach(device_t dev); 55 static int pmufreq_settings(device_t dev, struct cf_setting *sets, int *count); 56 static int pmufreq_set(device_t dev, const struct cf_setting *set); 57 static int pmufreq_get(device_t dev, struct cf_setting *set); 58 static int pmufreq_type(device_t dev, int *type); 59 60 static 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 {0, 0} 72 }; 73 74 static driver_t pmufreq_driver = { 75 "pmufreq", 76 pmufreq_methods, 77 sizeof(struct pmufreq_softc) 78 }; 79 80 DRIVER_MODULE(pmufreq, cpu, pmufreq_driver, 0, 0); 81 82 static void 83 pmufreq_identify(driver_t *driver, device_t parent) 84 { 85 phandle_t node; 86 uint32_t min_freq; 87 88 node = ofw_bus_get_node(parent); 89 if (OF_getprop(node, "min-clock-frequency", &min_freq, sizeof(min_freq)) == -1) 90 return; 91 92 /* Make sure we're not being doubly invoked. */ 93 if (device_find_child(parent, "pmufreq", -1) != NULL) 94 return; 95 96 /* 97 * We attach a child for every CPU since settings need to 98 * be performed on every CPU in the SMP case. 99 */ 100 if (BUS_ADD_CHILD(parent, 10, "pmufreq", -1) == NULL) 101 device_printf(parent, "add pmufreq child failed\n"); 102 } 103 104 static int 105 pmufreq_probe(device_t dev) 106 { 107 phandle_t node; 108 uint32_t min_freq; 109 110 if (resource_disabled("pmufreq", 0)) 111 return (ENXIO); 112 113 node = ofw_bus_get_node(device_get_parent(dev)); 114 /* 115 * A scalable MPC7455 has min-clock-frequency/max-clock-frequency as OFW 116 * properties of the 'cpu' node. 117 */ 118 if (OF_getprop(node, "min-clock-frequency", &min_freq, sizeof(min_freq)) == -1) 119 return (ENXIO); 120 device_set_desc(dev, "PMU-based frequency scaling"); 121 return (0); 122 } 123 124 static int 125 pmufreq_attach(device_t dev) 126 { 127 struct pmufreq_softc *sc; 128 phandle_t node; 129 130 sc = device_get_softc(dev); 131 sc->dev = dev; 132 133 node = ofw_bus_get_node(device_get_parent(dev)); 134 OF_getprop(node, "min-clock-frequency", &sc->minfreq, sizeof(sc->minfreq)); 135 OF_getprop(node, "max-clock-frequency", &sc->maxfreq, sizeof(sc->maxfreq)); 136 OF_getprop(node, "rounded-clock-frequency", &sc->curfreq, sizeof(sc->curfreq)); 137 sc->minfreq /= 1000000; 138 sc->maxfreq /= 1000000; 139 sc->curfreq /= 1000000; 140 141 cpufreq_register(dev); 142 return (0); 143 } 144 145 static int 146 pmufreq_settings(device_t dev, struct cf_setting *sets, int *count) 147 { 148 struct pmufreq_softc *sc; 149 150 sc = device_get_softc(dev); 151 if (sets == NULL || count == NULL) 152 return (EINVAL); 153 if (*count < 2) 154 return (E2BIG); 155 156 /* Return a list of valid settings for this driver. */ 157 memset(sets, CPUFREQ_VAL_UNKNOWN, sizeof(*sets) * 2); 158 159 sets[0].freq = sc->maxfreq; sets[0].dev = dev; 160 sets[1].freq = sc->minfreq; sets[1].dev = dev; 161 /* Set high latency for CPU frequency changes, it's a tedious process. */ 162 sets[0].lat = INT_MAX; 163 sets[1].lat = INT_MAX; 164 *count = 2; 165 166 return (0); 167 } 168 169 static int 170 pmufreq_set(device_t dev, const struct cf_setting *set) 171 { 172 struct pmufreq_softc *sc; 173 int error, speed_sel; 174 175 if (set == NULL) 176 return (EINVAL); 177 178 sc = device_get_softc(dev); 179 180 if (set->freq == sc->maxfreq) 181 speed_sel = 0; 182 else 183 speed_sel = 1; 184 185 error = pmu_set_speed(speed_sel); 186 if (error == 0) 187 sc->curfreq = set->freq; 188 189 return (error); 190 } 191 192 static int 193 pmufreq_get(device_t dev, struct cf_setting *set) 194 { 195 struct pmufreq_softc *sc; 196 197 if (set == NULL) 198 return (EINVAL); 199 sc = device_get_softc(dev); 200 201 set->freq = sc->curfreq; 202 set->dev = dev; 203 204 return (0); 205 } 206 207 static int 208 pmufreq_type(device_t dev, int *type) 209 { 210 211 if (type == NULL) 212 return (EINVAL); 213 214 *type = CPUFREQ_TYPE_ABSOLUTE; 215 return (0); 216 } 217