xref: /openbsd/sys/dev/acpi/acpihpet.c (revision 09467b48)
1 /* $OpenBSD: acpihpet.c,v 1.24 2020/07/06 13:33:08 pirofti 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/timetc.h>
22 
23 #include <machine/bus.h>
24 
25 #include <dev/acpi/acpireg.h>
26 #include <dev/acpi/acpivar.h>
27 #include <dev/acpi/acpidev.h>
28 
29 int acpihpet_attached;
30 
31 int acpihpet_match(struct device *, void *, void *);
32 void acpihpet_attach(struct device *, struct device *, void *);
33 int acpihpet_activate(struct device *, int);
34 
35 u_int acpihpet_gettime(struct timecounter *tc);
36 
37 uint64_t	acpihpet_r(bus_space_tag_t _iot, bus_space_handle_t _ioh,
38 		    bus_size_t _ioa);
39 void		acpihpet_w(bus_space_tag_t _iot, bus_space_handle_t _ioh,
40 		    bus_size_t _ioa, uint64_t _val);
41 
42 static struct timecounter hpet_timecounter = {
43 	acpihpet_gettime,	/* get_timecount */
44 	0,			/* no poll_pps */
45 	0xffffffff,		/* counter_mask (32 bits) */
46 	0,			/* frequency */
47 	0,			/* name */
48 	1000,			/* quality */
49 	NULL,			/* private bits */
50 	0,			/* expose to user */
51 };
52 
53 #define HPET_TIMERS	3
54 struct hpet_regs {
55 	uint64_t	configuration;
56 	uint64_t	interrupt_status;
57 	uint64_t	main_counter;
58 	struct {	/* timers */
59 		uint64_t config;
60 		uint64_t compare;
61 		uint64_t interrupt;
62 	} timers[HPET_TIMERS];
63 };
64 
65 struct acpihpet_softc {
66 	struct device		sc_dev;
67 
68 	bus_space_tag_t		sc_iot;
69 	bus_space_handle_t	sc_ioh;
70 
71 	uint32_t		sc_conf;
72 	struct hpet_regs	sc_save;
73 };
74 
75 struct cfattach acpihpet_ca = {
76 	sizeof(struct acpihpet_softc), acpihpet_match, acpihpet_attach,
77 	NULL, acpihpet_activate
78 };
79 
80 struct cfdriver acpihpet_cd = {
81 	NULL, "acpihpet", DV_DULL
82 };
83 
84 uint64_t
85 acpihpet_r(bus_space_tag_t iot, bus_space_handle_t ioh, bus_size_t ioa)
86 {
87 	uint64_t val;
88 
89 	val = bus_space_read_4(iot, ioh, ioa + 4);
90 	val = val << 32;
91 	val |= bus_space_read_4(iot, ioh, ioa);
92 	return (val);
93 }
94 
95 void
96 acpihpet_w(bus_space_tag_t iot, bus_space_handle_t ioh, bus_size_t ioa,
97     uint64_t val)
98 {
99 	bus_space_write_4(iot, ioh, ioa + 4, val >> 32);
100 	bus_space_write_4(iot, ioh, ioa, val & 0xffffffff);
101 }
102 
103 int
104 acpihpet_activate(struct device *self, int act)
105 {
106 	struct acpihpet_softc *sc = (struct acpihpet_softc *) self;
107 
108 	switch (act) {
109 	case DVACT_SUSPEND:
110 		/* stop, then save */
111 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
112 		    HPET_CONFIGURATION, sc->sc_conf);
113 
114 		sc->sc_save.configuration = acpihpet_r(sc->sc_iot,
115 		    sc->sc_ioh, HPET_CONFIGURATION);
116 		sc->sc_save.interrupt_status = acpihpet_r(sc->sc_iot,
117 		    sc->sc_ioh, HPET_INTERRUPT_STATUS);
118 		sc->sc_save.main_counter = acpihpet_r(sc->sc_iot,
119 		    sc->sc_ioh, HPET_MAIN_COUNTER);
120 		sc->sc_save.timers[0].config = acpihpet_r(sc->sc_iot,
121 		    sc->sc_ioh, HPET_TIMER0_CONFIG);
122 		sc->sc_save.timers[0].interrupt = acpihpet_r(sc->sc_iot,
123 		    sc->sc_ioh, HPET_TIMER0_INTERRUPT);
124 		sc->sc_save.timers[0].compare = acpihpet_r(sc->sc_iot,
125 		    sc->sc_ioh, HPET_TIMER0_COMPARE);
126 		sc->sc_save.timers[1].config = acpihpet_r(sc->sc_iot,
127 		    sc->sc_ioh, HPET_TIMER1_CONFIG);
128 		sc->sc_save.timers[1].interrupt = acpihpet_r(sc->sc_iot,
129 		    sc->sc_ioh, HPET_TIMER1_INTERRUPT);
130 		sc->sc_save.timers[1].compare = acpihpet_r(sc->sc_iot,
131 		    sc->sc_ioh, HPET_TIMER1_COMPARE);
132 		sc->sc_save.timers[2].config = acpihpet_r(sc->sc_iot,
133 		    sc->sc_ioh, HPET_TIMER2_CONFIG);
134 		sc->sc_save.timers[2].interrupt = acpihpet_r(sc->sc_iot,
135 		    sc->sc_ioh, HPET_TIMER2_INTERRUPT);
136 		sc->sc_save.timers[2].compare = acpihpet_r(sc->sc_iot,
137 		    sc->sc_ioh, HPET_TIMER2_COMPARE);
138 		break;
139 	case DVACT_RESUME:
140 		/* stop, restore, then restart */
141 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
142 		    HPET_CONFIGURATION, sc->sc_conf);
143 
144 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
145 		    HPET_CONFIGURATION, sc->sc_save.configuration);
146 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
147 		    HPET_INTERRUPT_STATUS, sc->sc_save.interrupt_status);
148 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
149 		    HPET_MAIN_COUNTER, sc->sc_save.main_counter);
150 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
151 		    HPET_TIMER0_CONFIG, sc->sc_save.timers[0].config);
152 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
153 		    HPET_TIMER0_INTERRUPT, sc->sc_save.timers[0].interrupt);
154 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
155 		    HPET_TIMER0_COMPARE, sc->sc_save.timers[0].compare);
156 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
157 		    HPET_TIMER1_CONFIG, sc->sc_save.timers[1].config);
158 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
159 		    HPET_TIMER1_INTERRUPT, sc->sc_save.timers[1].interrupt);
160 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
161 		    HPET_TIMER1_COMPARE, sc->sc_save.timers[1].compare);
162 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
163 		    HPET_TIMER2_CONFIG, sc->sc_save.timers[2].config);
164 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
165 		    HPET_TIMER2_INTERRUPT, sc->sc_save.timers[2].interrupt);
166 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
167 		    HPET_TIMER2_COMPARE, sc->sc_save.timers[2].compare);
168 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
169 		    HPET_CONFIGURATION, sc->sc_conf | 1);
170 		break;
171 	}
172 
173 	return 0;
174 }
175 
176 int
177 acpihpet_match(struct device *parent, void *match, void *aux)
178 {
179 	struct acpi_attach_args *aaa = aux;
180 	struct acpi_table_header *hdr;
181 
182 	/*
183 	 * If we do not have a table, it is not us; attach only once
184 	 */
185 	if (acpihpet_attached || aaa->aaa_table == NULL)
186 		return (0);
187 
188 	/*
189 	 * If it is an HPET table, we can attach
190 	 */
191 	hdr = (struct acpi_table_header *)aaa->aaa_table;
192 	if (memcmp(hdr->signature, HPET_SIG, sizeof(HPET_SIG) - 1) != 0)
193 		return (0);
194 
195 	return (1);
196 }
197 
198 void
199 acpihpet_attach(struct device *parent, struct device *self, void *aux)
200 {
201 	struct acpihpet_softc *sc = (struct acpihpet_softc *) self;
202 	struct acpi_softc *psc = (struct acpi_softc *)parent;
203 	struct acpi_attach_args *aaa = aux;
204 	struct acpi_hpet *hpet = (struct acpi_hpet *)aaa->aaa_table;
205 	uint64_t period, freq;	/* timer period in femtoseconds (10^-15) */
206 	uint32_t v1, v2;
207 	int timeout;
208 
209 	if (acpi_map_address(psc, &hpet->base_address, 0, HPET_REG_SIZE,
210 	    &sc->sc_ioh, &sc->sc_iot))	{
211 		printf(": can't map i/o space\n");
212 		return;
213 	}
214 
215 	/*
216 	 * Revisions 0x30 through 0x3a of the AMD SB700, with spread
217 	 * spectrum enabled, have an SMM based HPET emulation that's
218 	 * subtly broken.  The hardware is initialized upon first
219 	 * access of the configuration register.  Initialization takes
220 	 * some time during which the configuration register returns
221 	 * 0xffffffff.
222 	 */
223 	timeout = 1000;
224 	do {
225 		if (bus_space_read_4(sc->sc_iot, sc->sc_ioh,
226 		    HPET_CONFIGURATION) != 0xffffffff)
227 			break;
228 	} while(--timeout > 0);
229 
230 	if (timeout == 0) {
231 		printf(": disabled\n");
232 		return;
233 	}
234 
235 	/* enable hpet */
236 	sc->sc_conf = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
237 	    HPET_CONFIGURATION) & ~1;
238 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, HPET_CONFIGURATION,
239 	    sc->sc_conf | 1);
240 
241 	/* make sure hpet is working */
242 	v1 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER);
243 	delay(1);
244 	v2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER);
245 	if (v1 == v2) {
246 		printf(": counter not incrementing\n");
247 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
248 		    HPET_CONFIGURATION, sc->sc_conf);
249 		return;
250 	}
251 
252 	period = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
253 	    HPET_CAPABILITIES + sizeof(uint32_t));
254 
255 	/* Period must be > 0 and less than 100ns (10^8 fs) */
256 	if (period == 0 || period > HPET_MAX_PERIOD) {
257 		printf(": invalid period\n");
258 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
259 		    HPET_CONFIGURATION, sc->sc_conf);
260 		return;
261 	}
262 	freq = 1000000000000000ull / period;
263 	printf(": %lld Hz\n", freq);
264 
265 	hpet_timecounter.tc_frequency = (uint32_t)freq;
266 	hpet_timecounter.tc_priv = sc;
267 	hpet_timecounter.tc_name = sc->sc_dev.dv_xname;
268 	tc_init(&hpet_timecounter);
269 #if defined(__amd64__)
270 	extern void cpu_recalibrate_tsc(struct timecounter *);
271 	cpu_recalibrate_tsc(&hpet_timecounter);
272 #endif
273 	acpihpet_attached++;
274 }
275 
276 u_int
277 acpihpet_gettime(struct timecounter *tc)
278 {
279 	struct acpihpet_softc *sc = tc->tc_priv;
280 
281 	return (bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER));
282 }
283