xref: /openbsd/sys/dev/acpi/acpihpet.c (revision 264ca280)
1 /* $OpenBSD: acpihpet.c,v 1.21 2015/10/06 20:49:32 matthew 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 u_int64_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, u_int64_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 };
50 
51 #define HPET_TIMERS	3
52 struct hpet_regs {
53 	u_int64_t	configuration;
54 	u_int64_t	interrupt_status;
55 	u_int64_t	main_counter;
56 	struct {	/* timers */
57 		u_int64_t config;
58 		u_int64_t compare;
59 		u_int64_t interrupt;
60 	} timers[HPET_TIMERS];
61 };
62 
63 struct acpihpet_softc {
64 	struct device		sc_dev;
65 
66 	bus_space_tag_t		sc_iot;
67 	bus_space_handle_t	sc_ioh;
68 
69 	u_int32_t		sc_conf;
70 	struct hpet_regs	sc_save;
71 };
72 
73 struct cfattach acpihpet_ca = {
74 	sizeof(struct acpihpet_softc), acpihpet_match, acpihpet_attach,
75 	NULL, acpihpet_activate
76 };
77 
78 struct cfdriver acpihpet_cd = {
79 	NULL, "acpihpet", DV_DULL
80 };
81 
82 u_int64_t
83 acpihpet_r(bus_space_tag_t iot, bus_space_handle_t ioh, bus_size_t ioa)
84 {
85 	u_int64_t val;
86 
87 	val = bus_space_read_4(iot, ioh, ioa + 4);
88 	val = val << 32;
89 	val |= bus_space_read_4(iot, ioh, ioa);
90 	return (val);
91 }
92 
93 void
94 acpihpet_w(bus_space_tag_t iot, bus_space_handle_t ioh, bus_size_t ioa,
95     u_int64_t val)
96 {
97 	bus_space_write_4(iot, ioh, ioa + 4, val >> 32);
98 	bus_space_write_4(iot, ioh, ioa, val & 0xffffffff);
99 }
100 
101 int
102 acpihpet_activate(struct device *self, int act)
103 {
104 	struct acpihpet_softc *sc = (struct acpihpet_softc *) self;
105 
106 	switch (act) {
107 	case DVACT_SUSPEND:
108 		/* stop, then save */
109 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
110 		    HPET_CONFIGURATION, sc->sc_conf);
111 
112 		sc->sc_save.configuration = acpihpet_r(sc->sc_iot,
113 		    sc->sc_ioh, HPET_CONFIGURATION);
114 		sc->sc_save.interrupt_status = acpihpet_r(sc->sc_iot,
115 		    sc->sc_ioh, HPET_INTERRUPT_STATUS);
116 		sc->sc_save.main_counter = acpihpet_r(sc->sc_iot,
117 		    sc->sc_ioh, HPET_MAIN_COUNTER);
118 		sc->sc_save.timers[0].config = acpihpet_r(sc->sc_iot,
119 		    sc->sc_ioh, HPET_TIMER0_CONFIG);
120 		sc->sc_save.timers[0].interrupt = acpihpet_r(sc->sc_iot,
121 		    sc->sc_ioh, HPET_TIMER0_INTERRUPT);
122 		sc->sc_save.timers[0].compare = acpihpet_r(sc->sc_iot,
123 		    sc->sc_ioh, HPET_TIMER0_COMPARE);
124 		sc->sc_save.timers[1].config = acpihpet_r(sc->sc_iot,
125 		    sc->sc_ioh, HPET_TIMER1_CONFIG);
126 		sc->sc_save.timers[1].interrupt = acpihpet_r(sc->sc_iot,
127 		    sc->sc_ioh, HPET_TIMER1_INTERRUPT);
128 		sc->sc_save.timers[1].compare = acpihpet_r(sc->sc_iot,
129 		    sc->sc_ioh, HPET_TIMER1_COMPARE);
130 		sc->sc_save.timers[2].config = acpihpet_r(sc->sc_iot,
131 		    sc->sc_ioh, HPET_TIMER2_CONFIG);
132 		sc->sc_save.timers[2].interrupt = acpihpet_r(sc->sc_iot,
133 		    sc->sc_ioh, HPET_TIMER2_INTERRUPT);
134 		sc->sc_save.timers[2].compare = acpihpet_r(sc->sc_iot,
135 		    sc->sc_ioh, HPET_TIMER2_COMPARE);
136 		break;
137 	case DVACT_RESUME:
138 		/* stop, restore, then restart */
139 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
140 		    HPET_CONFIGURATION, sc->sc_conf);
141 
142 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
143 		    HPET_CONFIGURATION, sc->sc_save.configuration);
144 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
145 		    HPET_INTERRUPT_STATUS, sc->sc_save.interrupt_status);
146 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
147 		    HPET_MAIN_COUNTER, sc->sc_save.main_counter);
148 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
149 		    HPET_TIMER0_CONFIG, sc->sc_save.timers[0].config);
150 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
151 		    HPET_TIMER0_INTERRUPT, sc->sc_save.timers[0].interrupt);
152 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
153 		    HPET_TIMER0_COMPARE, sc->sc_save.timers[0].compare);
154 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
155 		    HPET_TIMER1_CONFIG, sc->sc_save.timers[1].config);
156 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
157 		    HPET_TIMER1_INTERRUPT, sc->sc_save.timers[1].interrupt);
158 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
159 		    HPET_TIMER1_COMPARE, sc->sc_save.timers[1].compare);
160 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
161 		    HPET_TIMER2_CONFIG, sc->sc_save.timers[2].config);
162 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
163 		    HPET_TIMER2_INTERRUPT, sc->sc_save.timers[2].interrupt);
164 		acpihpet_w(sc->sc_iot, sc->sc_ioh,
165 		    HPET_TIMER2_COMPARE, sc->sc_save.timers[2].compare);
166 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
167 		    HPET_CONFIGURATION, sc->sc_conf | 1);
168 		break;
169 	}
170 
171 	return 0;
172 }
173 
174 int
175 acpihpet_match(struct device *parent, void *match, void *aux)
176 {
177 	struct acpi_attach_args *aaa = aux;
178 	struct acpi_table_header *hdr;
179 
180 	/*
181 	 * If we do not have a table, it is not us; attach only once
182 	 */
183 	if (acpihpet_attached || aaa->aaa_table == NULL)
184 		return (0);
185 
186 	/*
187 	 * If it is an HPET table, we can attach
188 	 */
189 	hdr = (struct acpi_table_header *)aaa->aaa_table;
190 	if (memcmp(hdr->signature, HPET_SIG, sizeof(HPET_SIG) - 1) != 0)
191 		return (0);
192 
193 	return (1);
194 }
195 
196 void
197 acpihpet_attach(struct device *parent, struct device *self, void *aux)
198 {
199 	struct acpihpet_softc *sc = (struct acpihpet_softc *) self;
200 	struct acpi_softc *psc = (struct acpi_softc *)parent;
201 	struct acpi_attach_args *aaa = aux;
202 	struct acpi_hpet *hpet = (struct acpi_hpet *)aaa->aaa_table;
203 	u_int64_t period, freq;	/* timer period in femtoseconds (10^-15) */
204 	u_int32_t v1, v2;
205 	int timeout;
206 
207 	if (acpi_map_address(psc, &hpet->base_address, 0, HPET_REG_SIZE,
208 	    &sc->sc_ioh, &sc->sc_iot))	{
209 		printf(": can't map i/o space\n");
210 		return;
211 	}
212 
213 	/*
214 	 * Revisions 0x30 through 0x3a of the AMD SB700, with spread
215 	 * spectrum enabled, have an SMM based HPET emulation that's
216 	 * subtly broken.  The hardware is initialized upon first
217 	 * access of the configuration register.  Initialization takes
218 	 * some time during which the configuration register returns
219 	 * 0xffffffff.
220 	 */
221 	timeout = 1000;
222 	do {
223 		if (bus_space_read_4(sc->sc_iot, sc->sc_ioh,
224 		    HPET_CONFIGURATION) != 0xffffffff)
225 			break;
226 	} while(--timeout > 0);
227 
228 	if (timeout == 0) {
229 		printf(": disabled\n");
230 		return;
231 	}
232 
233 	/* enable hpet */
234 	sc->sc_conf = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
235 	    HPET_CONFIGURATION) & ~1;
236 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, HPET_CONFIGURATION,
237 	    sc->sc_conf | 1);
238 
239 	/* make sure hpet is working */
240 	v1 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER);
241 	delay(1);
242 	v2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER);
243 	if (v1 == v2) {
244 		printf(": counter not incrementing\n");
245 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
246 		    HPET_CONFIGURATION, sc->sc_conf);
247 		return;
248 	}
249 
250 	period = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
251 	    HPET_CAPABILITIES + sizeof(u_int32_t));
252 
253 	/* Period must be > 0 and less than 100ns (10^8 fs) */
254 	if (period == 0 || period > HPET_MAX_PERIOD) {
255 		printf(": invalid period\n");
256 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
257 		    HPET_CONFIGURATION, sc->sc_conf);
258 		return;
259 	}
260 	freq = 1000000000000000ull / period;
261 	printf(": %lld Hz\n", freq);
262 
263 	hpet_timecounter.tc_frequency = (u_int32_t)freq;
264 	hpet_timecounter.tc_priv = sc;
265 	hpet_timecounter.tc_name = sc->sc_dev.dv_xname;
266 	tc_init(&hpet_timecounter);
267 	acpihpet_attached++;
268 }
269 
270 u_int
271 acpihpet_gettime(struct timecounter *tc)
272 {
273 	struct acpihpet_softc *sc = tc->tc_priv;
274 
275 	return (bus_space_read_4(sc->sc_iot, sc->sc_ioh, HPET_MAIN_COUNTER));
276 }
277