xref: /openbsd/sys/dev/acpi/acpitimer.c (revision 3d8817e4)
1 /* $OpenBSD: acpitimer.c,v 1.9 2011/04/22 18:22:01 jordan 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/malloc.h>
22 #ifdef __HAVE_TIMECOUNTER
23 #include <sys/timetc.h>
24 #endif
25 
26 #include <machine/bus.h>
27 
28 #include <dev/acpi/acpireg.h>
29 #include <dev/acpi/acpivar.h>
30 
31 int acpitimermatch(struct device *, void *, void *);
32 void acpitimerattach(struct device *, struct device *, void *);
33 
34 #ifdef __HAVE_TIMECOUNTER
35 u_int acpi_get_timecount(struct timecounter *tc);
36 
37 static struct timecounter acpi_timecounter = {
38 	acpi_get_timecount,	/* get_timecount */
39 	0,			/* no poll_pps */
40 	0x00ffffff,		/* counter_mask (24 bits) */
41 	ACPI_FREQUENCY,		/* frequency */
42 	0,			/* name */
43 	1000			/* quality */
44 };
45 #endif
46 
47 struct acpitimer_softc {
48 	struct device		sc_dev;
49 
50 	bus_space_tag_t		sc_iot;
51 	bus_space_handle_t	sc_ioh;
52 };
53 
54 struct cfattach acpitimer_ca = {
55 	sizeof(struct acpitimer_softc), acpitimermatch, acpitimerattach
56 };
57 
58 struct cfdriver acpitimer_cd = {
59 	NULL, "acpitimer", DV_DULL
60 };
61 
62 int
63 acpitimermatch(struct device *parent, void *match, void *aux)
64 {
65 	struct acpi_attach_args *aa = aux;
66 	struct cfdata *cf = match;
67 
68 	/* sanity */
69 	if (aa->aaa_name == NULL ||
70 	    strcmp(aa->aaa_name, cf->cf_driver->cd_name) != 0 ||
71 	    aa->aaa_table != NULL)
72 		return (0);
73 
74 	return (1);
75 }
76 
77 void
78 acpitimerattach(struct device *parent, struct device *self, void *aux)
79 {
80 	struct acpitimer_softc *sc = (struct acpitimer_softc *) self;
81 	struct acpi_softc *psc = (struct acpi_softc *) parent;
82 	int rc;
83 
84 	if (psc->sc_fadt->hdr_revision >= 3 &&
85 	    psc->sc_fadt->x_pm_tmr_blk.address != 0)
86 		rc = acpi_map_address(psc, &psc->sc_fadt->x_pm_tmr_blk, 0,
87 		    psc->sc_fadt->pm_tmr_len, &sc->sc_ioh, &sc->sc_iot);
88 	else
89 		rc = acpi_map_address(psc, NULL, psc->sc_fadt->pm_tmr_blk,
90 		    psc->sc_fadt->pm_tmr_len, &sc->sc_ioh, &sc->sc_iot);
91 	if (rc) {
92 		printf(": can't map i/o space\n");
93 		return;
94 	}
95 
96 	printf(": %d Hz, %d bits\n", ACPI_FREQUENCY,
97 	    psc->sc_fadt->flags & FADT_TMR_VAL_EXT ? 32 : 24);
98 
99 #ifdef __HAVE_TIMECOUNTER
100 	if (psc->sc_fadt->flags & FADT_TMR_VAL_EXT)
101 		acpi_timecounter.tc_counter_mask = 0xffffffffU;
102 	acpi_timecounter.tc_priv = sc;
103 	acpi_timecounter.tc_name = sc->sc_dev.dv_xname;
104 	tc_init(&acpi_timecounter);
105 #endif
106 }
107 
108 
109 #ifdef __HAVE_TIMECOUNTER
110 u_int
111 acpi_get_timecount(struct timecounter *tc)
112 {
113 	struct acpitimer_softc *sc = tc->tc_priv;
114 	u_int u1, u2, u3;
115 
116 	u2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, 0);
117 	u3 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, 0);
118 	do {
119 		u1 = u2;
120 		u2 = u3;
121 		u3 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, 0);
122 	} while (u1 > u2 || u2 > u3);
123 
124 	return (u2);
125 }
126 #endif
127