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
pmufreq_identify(driver_t * driver,device_t parent)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
pmufreq_probe(device_t dev)108 pmufreq_probe(device_t dev)
109 {
110 struct pmufreq_softc *sc;
111 phandle_t node;
112 uint32_t min_freq;
113
114 if (resource_disabled("pmufreq", 0))
115 return (ENXIO);
116
117 sc = device_get_softc(dev);
118 node = ofw_bus_get_node(device_get_parent(dev));
119 /*
120 * A scalable MPC7455 has min-clock-frequency/max-clock-frequency as OFW
121 * properties of the 'cpu' node.
122 */
123 if (OF_getprop(node, "min-clock-frequency", &min_freq, sizeof(min_freq)) == -1)
124 return (ENXIO);
125 device_set_desc(dev, "PMU-based frequency scaling");
126 return (0);
127 }
128
129 static int
pmufreq_attach(device_t dev)130 pmufreq_attach(device_t dev)
131 {
132 struct pmufreq_softc *sc;
133 phandle_t node;
134
135 sc = device_get_softc(dev);
136 sc->dev = dev;
137
138 node = ofw_bus_get_node(device_get_parent(dev));
139 OF_getprop(node, "min-clock-frequency", &sc->minfreq, sizeof(sc->minfreq));
140 OF_getprop(node, "max-clock-frequency", &sc->maxfreq, sizeof(sc->maxfreq));
141 OF_getprop(node, "rounded-clock-frequency", &sc->curfreq, sizeof(sc->curfreq));
142 sc->minfreq /= 1000000;
143 sc->maxfreq /= 1000000;
144 sc->curfreq /= 1000000;
145
146 cpufreq_register(dev);
147 return (0);
148 }
149
150 static int
pmufreq_settings(device_t dev,struct cf_setting * sets,int * count)151 pmufreq_settings(device_t dev, struct cf_setting *sets, int *count)
152 {
153 struct pmufreq_softc *sc;
154
155 sc = device_get_softc(dev);
156 if (sets == NULL || count == NULL)
157 return (EINVAL);
158 if (*count < 2)
159 return (E2BIG);
160
161 /* Return a list of valid settings for this driver. */
162 memset(sets, CPUFREQ_VAL_UNKNOWN, sizeof(*sets) * 2);
163
164 sets[0].freq = sc->maxfreq; sets[0].dev = dev;
165 sets[1].freq = sc->minfreq; sets[1].dev = dev;
166 /* Set high latency for CPU frequency changes, it's a tedious process. */
167 sets[0].lat = INT_MAX;
168 sets[1].lat = INT_MAX;
169 *count = 2;
170
171 return (0);
172 }
173
174 static int
pmufreq_set(device_t dev,const struct cf_setting * set)175 pmufreq_set(device_t dev, const struct cf_setting *set)
176 {
177 struct pmufreq_softc *sc;
178 int error, speed_sel;
179
180 if (set == NULL)
181 return (EINVAL);
182
183 sc = device_get_softc(dev);
184
185 if (set->freq == sc->maxfreq)
186 speed_sel = 0;
187 else
188 speed_sel = 1;
189
190 error = pmu_set_speed(speed_sel);
191 if (error == 0)
192 sc->curfreq = set->freq;
193
194 return (error);
195 }
196
197 static int
pmufreq_get(device_t dev,struct cf_setting * set)198 pmufreq_get(device_t dev, struct cf_setting *set)
199 {
200 struct pmufreq_softc *sc;
201
202 if (set == NULL)
203 return (EINVAL);
204 sc = device_get_softc(dev);
205
206 set->freq = sc->curfreq;
207 set->dev = dev;
208
209 return (0);
210 }
211
212 static int
pmufreq_type(device_t dev,int * type)213 pmufreq_type(device_t dev, int *type)
214 {
215
216 if (type == NULL)
217 return (EINVAL);
218
219 *type = CPUFREQ_TYPE_ABSOLUTE;
220 return (0);
221 }
222