xref: /freebsd/sys/dev/acpica/acpi_timer.c (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
1 /*-
2  * Copyright (c) 2000 Michael Smith
3  * Copyright (c) 2000 BSDi
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  *	$FreeBSD$
28  */
29 
30 #include "opt_acpi.h"
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/bus.h>
34 
35 #include "acpi.h"
36 
37 #include <dev/acpica/acpivar.h>
38 
39 #define ACPITIMER_MAGIC 0x524d4954	/* "TIMR" */
40 
41 struct acpi_timer_softc {
42     device_t	tm_dev;
43 };
44 
45 static void	acpi_timer_identify(driver_t *driver, device_t parent);
46 static int	acpi_timer_probe(device_t dev);
47 static int	acpi_timer_attach(device_t dev);
48 
49 static device_method_t acpi_timer_methods[] = {
50     /* Device interface */
51     DEVMETHOD(device_identify,	acpi_timer_identify),
52     DEVMETHOD(device_probe,	acpi_timer_probe),
53     DEVMETHOD(device_attach,	acpi_timer_attach),
54 
55     {0, 0}
56 };
57 
58 static driver_t acpi_timer_driver = {
59     "acpi_timer",
60     acpi_timer_methods,
61     sizeof(struct acpi_timer_softc),
62 };
63 
64 devclass_t acpi_timer_devclass;
65 DRIVER_MODULE(acpi_timer, acpi, acpi_timer_driver, acpi_timer_devclass, 0, 0);
66 
67 static void
68 acpi_timer_identify(driver_t *driver, device_t parent)
69 {
70     static FIXED_ACPI_DESCRIPTION_TABLE	facp;
71     ACPI_BUFFER				buf;
72     ACPI_STATUS				status;
73     device_t				dev;
74     char				desc[40];
75 
76     buf.Pointer = &facp;
77     buf.Length = sizeof(facp);
78     if ((status = AcpiGetTable(ACPI_TABLE_FACP, 1, &buf)) != AE_OK) {
79 	device_printf(parent, "can't locate FACP - %s\n", acpi_strerror(status));
80 	return;
81     }
82     if (buf.Length != sizeof(facp)) {
83 	device_printf(parent, "invalid FACP\n");
84 	return;
85     }
86 
87     if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_timer", 0)) == NULL) {
88 	device_printf(parent, "could not add acpi_timer0\n");
89 	return;
90     }
91     if (acpi_set_magic(dev, ACPITIMER_MAGIC)) {
92 	device_printf(dev, "could not set magic\n");
93 	return;
94     }
95 
96     sprintf(desc, "%d-bit timer at 3.579545MHz", facp.TmrValExt ? 32 : 24);
97     device_set_desc_copy(dev, desc);
98 }
99 
100 static int
101 acpi_timer_probe(device_t dev)
102 {
103     if (acpi_get_magic(dev) == ACPITIMER_MAGIC)
104 	return(0);
105     return(ENXIO);
106 }
107 
108 static int
109 acpi_timer_attach(device_t dev)
110 {
111     struct acpi_timer_softc		*sc;
112 
113     sc = device_get_softc(dev);
114     sc->tm_dev = dev;
115 
116     return(0);
117 }
118