1 /* $OpenBSD: acpihpet.c,v 1.31 2023/02/04 19:19:37 cheloha Exp $ */
2 /*
3 * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include <sys/param.h>
19 #include <sys/systm.h>
20 #include <sys/device.h>
21 #include <sys/stdint.h>
22 #include <sys/timetc.h>
23
24 #include <machine/bus.h>
25 #include <machine/cpu.h>
26
27 #include <dev/acpi/acpireg.h>
28 #include <dev/acpi/acpivar.h>
29 #include <dev/acpi/acpidev.h>
30
31 int acpihpet_attached;
32
33 int acpihpet_match(struct device *, void *, void *);
34 void acpihpet_attach(struct device *, struct device *, void *);
35 int acpihpet_activate(struct device *, int);
36 void acpihpet_delay(int);
37 u_int acpihpet_gettime(struct timecounter *tc);
38
39 uint64_t acpihpet_r(bus_space_tag_t _iot, bus_space_handle_t _ioh,
40 bus_size_t _ioa);
41 void acpihpet_w(bus_space_tag_t _iot, bus_space_handle_t _ioh,
42 bus_size_t _ioa, uint64_t _val);
43
44 static struct timecounter hpet_timecounter = {
45 .tc_get_timecount = acpihpet_gettime,
46 .tc_counter_mask = 0xffffffff,
47 .tc_frequency = 0,
48 .tc_name = 0,
49 .tc_quality = 1000,
50 .tc_priv = NULL,
51 .tc_user = 0,
52 };
53
54 #define HPET_TIMERS 3
55 struct hpet_regs {
56 uint64_t configuration;
57 uint64_t interrupt_status;
58 uint64_t main_counter;
59 struct { /* timers */
60 uint64_t config;
61 uint64_t compare;
62 uint64_t interrupt;
63 } timers[HPET_TIMERS];
64 };
65
66 struct acpihpet_softc {
67 struct device sc_dev;
68
69 bus_space_tag_t sc_iot;
70 bus_space_handle_t sc_ioh;
71
72 uint32_t sc_conf;
73 struct hpet_regs sc_save;
74 };
75
76 const struct cfattach acpihpet_ca = {
77 sizeof(struct acpihpet_softc), acpihpet_match, acpihpet_attach,
78 NULL, acpihpet_activate
79 };
80
81 struct cfdriver acpihpet_cd = {
82 NULL, "acpihpet", DV_DULL
83 };
84
85 uint64_t
acpihpet_r(bus_space_tag_t iot,bus_space_handle_t ioh,bus_size_t ioa)86 acpihpet_r(bus_space_tag_t iot, bus_space_handle_t ioh, bus_size_t ioa)
87 {
88 uint64_t val;
89
90 val = bus_space_read_4(iot, ioh, ioa + 4);
91 val = val << 32;
92 val |= bus_space_read_4(iot, ioh, ioa);
93 return (val);
94 }
95
96 void
acpihpet_w(bus_space_tag_t iot,bus_space_handle_t ioh,bus_size_t ioa,uint64_t val)97 acpihpet_w(bus_space_tag_t iot, bus_space_handle_t ioh, bus_size_t ioa,
98 uint64_t val)
99 {
100 bus_space_write_4(iot, ioh, ioa + 4, val >> 32);
101 bus_space_write_4(iot, ioh, ioa, val & 0xffffffff);
102 }
103
104 int
acpihpet_activate(struct device * self,int act)105 acpihpet_activate(struct device *self, int act)
106 {
107 struct acpihpet_softc *sc = (struct acpihpet_softc *) self;
108
109 switch (act) {
110 case DVACT_SUSPEND:
111 delay_fini(acpihpet_delay);
112
113 /* stop, then save */
114 bus_space_write_4(sc->sc_iot, sc->sc_ioh,
115 HPET_CONFIGURATION, sc->sc_conf);
116
117 sc->sc_save.configuration = acpihpet_r(sc->sc_iot,
118 sc->sc_ioh, HPET_CONFIGURATION);
119 sc->sc_save.interrupt_status = acpihpet_r(sc->sc_iot,
120 sc->sc_ioh, HPET_INTERRUPT_STATUS);
121 sc->sc_save.main_counter = acpihpet_r(sc->sc_iot,
122 sc->sc_ioh, HPET_MAIN_COUNTER);
123 sc->sc_save.timers[0].config = acpihpet_r(sc->sc_iot,
124 sc->sc_ioh, HPET_TIMER0_CONFIG);
125 sc->sc_save.timers[0].interrupt = acpihpet_r(sc->sc_iot,
126 sc->sc_ioh, HPET_TIMER0_INTERRUPT);
127 sc->sc_save.timers[0].compare = acpihpet_r(sc->sc_iot,
128 sc->sc_ioh, HPET_TIMER0_COMPARE);
129 sc->sc_save.timers[1].config = acpihpet_r(sc->sc_iot,
130 sc->sc_ioh, HPET_TIMER1_CONFIG);
131 sc->sc_save.timers[1].interrupt = acpihpet_r(sc->sc_iot,
132 sc->sc_ioh, HPET_TIMER1_INTERRUPT);
133 sc->sc_save.timers[1].compare = acpihpet_r(sc->sc_iot,
134 sc->sc_ioh, HPET_TIMER1_COMPARE);
135 sc->sc_save.timers[2].config = acpihpet_r(sc->sc_iot,
136 sc->sc_ioh, HPET_TIMER2_CONFIG);
137 sc->sc_save.timers[2].interrupt = acpihpet_r(sc->sc_iot,
138 sc->sc_ioh, HPET_TIMER2_INTERRUPT);
139 sc->sc_save.timers[2].compare = acpihpet_r(sc->sc_iot,
140 sc->sc_ioh, HPET_TIMER2_COMPARE);
141 break;
142 case DVACT_RESUME:
143 /* stop, restore, then restart */
144 bus_space_write_4(sc->sc_iot, sc->sc_ioh,
145 HPET_CONFIGURATION, sc->sc_conf);
146
147 acpihpet_w(sc->sc_iot, sc->sc_ioh,
148 HPET_CONFIGURATION, sc->sc_save.configuration);
149 acpihpet_w(sc->sc_iot, sc->sc_ioh,
150 HPET_INTERRUPT_STATUS, sc->sc_save.interrupt_status);
151 acpihpet_w(sc->sc_iot, sc->sc_ioh,
152 HPET_MAIN_COUNTER, sc->sc_save.main_counter);
153 acpihpet_w(sc->sc_iot, sc->sc_ioh,
154 HPET_TIMER0_CONFIG, sc->sc_save.timers[0].config);
155 acpihpet_w(sc->sc_iot, sc->sc_ioh,
156 HPET_TIMER0_INTERRUPT, sc->sc_save.timers[0].interrupt);
157 acpihpet_w(sc->sc_iot, sc->sc_ioh,
158 HPET_TIMER0_COMPARE, sc->sc_save.timers[0].compare);
159 acpihpet_w(sc->sc_iot, sc->sc_ioh,
160 HPET_TIMER1_CONFIG, sc->sc_save.timers[1].config);
161 acpihpet_w(sc->sc_iot, sc->sc_ioh,
162 HPET_TIMER1_INTERRUPT, sc->sc_save.timers[1].interrupt);
163 acpihpet_w(sc->sc_iot, sc->sc_ioh,
164 HPET_TIMER1_COMPARE, sc->sc_save.timers[1].compare);
165 acpihpet_w(sc->sc_iot, sc->sc_ioh,
166 HPET_TIMER2_CONFIG, sc->sc_save.timers[2].config);
167 acpihpet_w(sc->sc_iot, sc->sc_ioh,
168 HPET_TIMER2_INTERRUPT, sc->sc_save.timers[2].interrupt);
169 acpihpet_w(sc->sc_iot, sc->sc_ioh,
170 HPET_TIMER2_COMPARE, sc->sc_save.timers[2].compare);
171 bus_space_write_4(sc->sc_iot, sc->sc_ioh,
172 HPET_CONFIGURATION, sc->sc_conf | 1);
173
174 delay_init(acpihpet_delay, 2000);
175 break;
176 }
177
178 return 0;
179 }
180
181 int
acpihpet_match(struct device * parent,void * match,void * aux)182 acpihpet_match(struct device *parent, void *match, void *aux)
183 {
184 struct acpi_attach_args *aaa = aux;
185 struct acpi_table_header *hdr;
186
187 /*
188 * If we do not have a table, it is not us; attach only once
189 */
190 if (acpihpet_attached || aaa->aaa_table == NULL)
191 return (0);
192
193 /*
194 * If it is an HPET table, we can attach
195 */
196 hdr = (struct acpi_table_header *)aaa->aaa_table;
197 if (memcmp(hdr->signature, HPET_SIG, sizeof(HPET_SIG) - 1) != 0)
198 return (0);
199
200 return (1);
201 }
202
203 void
acpihpet_attach(struct device * parent,struct device * self,void * aux)204 acpihpet_attach(struct device *parent, struct device *self, void *aux)
205 {
206 struct acpihpet_softc *sc = (struct acpihpet_softc *) self;
207 struct acpi_softc *psc = (struct acpi_softc *)parent;
208 struct acpi_attach_args *aaa = aux;
209 struct acpi_hpet *hpet = (struct acpi_hpet *)aaa->aaa_table;
210 uint64_t period, freq; /* timer period in femtoseconds (10^-15) */
211 uint32_t v1, v2;
212 int timeout;
213
214 if (acpi_map_address(psc, &hpet->base_address, 0, HPET_REG_SIZE,
215 &sc->sc_ioh, &sc->sc_iot)) {
216 printf(": can't map i/o space\n");
217 return;
218 }
219
220 /*
221 * Revisions 0x30 through 0x3a of the AMD SB700, with spread
222 * spectrum enabled, have an SMM based HPET emulation that's
223 * subtly broken. The hardware is initialized upon first
224 * access of the configuration register. Initialization takes
225 * some time during which the configuration register returns
226 * 0xffffffff.
227 */
228 timeout = 1000;
229 do {
230 if (bus_space_read_4(sc->sc_iot, sc->sc_ioh,
231 HPET_CONFIGURATION) != 0xffffffff)
232 break;
233 } while(--timeout > 0);
234
235 if (timeout == 0) {
236 printf(": disabled\n");
237 return;
238 }
239
240 /* enable hpet */
241 sc->sc_conf = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
242 HPET_CONFIGURATION) & ~1;
243 bus_space_write_4(sc->sc_iot, sc->sc_ioh, HPET_CONFIGURATION,
244 sc->sc_conf | 1);
245
246 /* make sure hpet is working */
247 v1 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER);
248 delay(1);
249 v2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER);
250 if (v1 == v2) {
251 printf(": counter not incrementing\n");
252 bus_space_write_4(sc->sc_iot, sc->sc_ioh,
253 HPET_CONFIGURATION, sc->sc_conf);
254 return;
255 }
256
257 period = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
258 HPET_CAPABILITIES + sizeof(uint32_t));
259
260 /* Period must be > 0 and less than 100ns (10^8 fs) */
261 if (period == 0 || period > HPET_MAX_PERIOD) {
262 printf(": invalid period\n");
263 bus_space_write_4(sc->sc_iot, sc->sc_ioh,
264 HPET_CONFIGURATION, sc->sc_conf);
265 return;
266 }
267 freq = 1000000000000000ull / period;
268 printf(": %lld Hz\n", freq);
269
270 hpet_timecounter.tc_frequency = freq;
271 hpet_timecounter.tc_priv = sc;
272 hpet_timecounter.tc_name = sc->sc_dev.dv_xname;
273 tc_init(&hpet_timecounter);
274
275 delay_init(acpihpet_delay, 2000);
276
277 #if defined(__amd64__)
278 extern void cpu_recalibrate_tsc(struct timecounter *);
279 cpu_recalibrate_tsc(&hpet_timecounter);
280 #endif
281 acpihpet_attached++;
282 }
283
284 void
acpihpet_delay(int usecs)285 acpihpet_delay(int usecs)
286 {
287 uint64_t count = 0, cycles;
288 struct acpihpet_softc *sc = hpet_timecounter.tc_priv;
289 uint32_t val1, val2;
290
291 val2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER);
292 cycles = usecs * hpet_timecounter.tc_frequency / 1000000;
293 while (count < cycles) {
294 CPU_BUSY_CYCLE();
295 val1 = val2;
296 val2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
297 HPET_MAIN_COUNTER);
298 count += val2 - val1;
299 }
300 }
301
302 u_int
acpihpet_gettime(struct timecounter * tc)303 acpihpet_gettime(struct timecounter *tc)
304 {
305 struct acpihpet_softc *sc = tc->tc_priv;
306
307 return (bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER));
308 }
309