acpi_timer.c revision 1.10.10.4 1 1.10.10.4 yamt /* $NetBSD: acpi_timer.c,v 1.10.10.4 2010/08/11 22:53:16 yamt Exp $ */
2 1.10.10.3 yamt
3 1.10.10.3 yamt /*-
4 1.10.10.3 yamt * Copyright (c) 2006 Matthias Drochner <drochner (at) NetBSD.org>
5 1.10.10.3 yamt * All rights reserved.
6 1.10.10.3 yamt *
7 1.10.10.3 yamt * Redistribution and use in source and binary forms, with or without
8 1.10.10.3 yamt * modification, are permitted provided that the following conditions
9 1.10.10.3 yamt * are met:
10 1.10.10.3 yamt * 1. Redistributions of source code must retain the above copyright
11 1.10.10.3 yamt * notice, this list of conditions and the following disclaimer.
12 1.10.10.3 yamt * 2. Redistributions in binary form must reproduce the above copyright
13 1.10.10.3 yamt * notice, this list of conditions and the following disclaimer in the
14 1.10.10.3 yamt * documentation and/or other materials provided with the distribution.
15 1.10.10.3 yamt *
16 1.10.10.3 yamt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 1.10.10.3 yamt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 1.10.10.3 yamt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 1.10.10.3 yamt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 1.10.10.3 yamt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 1.10.10.3 yamt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 1.10.10.3 yamt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 1.10.10.3 yamt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 1.10.10.3 yamt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 1.10.10.3 yamt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 1.10.10.3 yamt * POSSIBILITY OF SUCH DAMAGE.
27 1.10.10.3 yamt */
28 1.4 xtraeme
29 1.4 xtraeme #include <sys/cdefs.h>
30 1.10.10.4 yamt __KERNEL_RCSID(0, "$NetBSD: acpi_timer.c,v 1.10.10.4 2010/08/11 22:53:16 yamt Exp $");
31 1.1 drochner
32 1.1 drochner #include <sys/types.h>
33 1.1 drochner #include <sys/systm.h>
34 1.1 drochner #include <sys/time.h>
35 1.1 drochner #include <sys/timetc.h>
36 1.10.10.3 yamt
37 1.10.10.3 yamt #include <dev/acpi/acpivar.h>
38 1.10 joerg #include <dev/acpi/acpi_timer.h>
39 1.10.10.3 yamt
40 1.10.10.2 yamt #include <machine/acpi_machdep.h>
41 1.1 drochner
42 1.10.10.4 yamt static int acpitimer_test(void);
43 1.1 drochner
44 1.1 drochner static struct timecounter acpi_timecounter = {
45 1.2 drochner acpitimer_read_safe,
46 1.1 drochner 0,
47 1.1 drochner 0x00ffffff,
48 1.1 drochner PM_TIMER_FREQUENCY,
49 1.2 drochner "ACPI-Safe",
50 1.6 christos 900,
51 1.6 christos NULL,
52 1.6 christos NULL,
53 1.1 drochner };
54 1.1 drochner
55 1.1 drochner int
56 1.10.10.4 yamt acpitimer_init(struct acpi_softc *sc)
57 1.1 drochner {
58 1.10.10.4 yamt ACPI_STATUS res;
59 1.1 drochner uint32_t bits;
60 1.2 drochner int i, j;
61 1.1 drochner
62 1.1 drochner res = AcpiGetTimerResolution(&bits);
63 1.10.10.4 yamt
64 1.1 drochner if (res != AE_OK)
65 1.10.10.4 yamt return -1;
66 1.1 drochner
67 1.1 drochner if (bits == 32)
68 1.1 drochner acpi_timecounter.tc_counter_mask = 0xffffffff;
69 1.2 drochner
70 1.10.10.4 yamt for (i = j = 0; i < 10; i++)
71 1.2 drochner j += acpitimer_test();
72 1.3 xtraeme
73 1.2 drochner if (j >= 10) {
74 1.2 drochner acpi_timecounter.tc_name = "ACPI-Fast";
75 1.2 drochner acpi_timecounter.tc_get_timecount = acpitimer_read_fast;
76 1.2 drochner acpi_timecounter.tc_quality = 1000;
77 1.2 drochner }
78 1.10.10.4 yamt
79 1.1 drochner tc_init(&acpi_timecounter);
80 1.1 drochner
81 1.10.10.4 yamt aprint_debug_dev(sc->sc_dev,
82 1.10.10.4 yamt "%s %d-bit timer\n", acpi_timecounter.tc_name, bits);
83 1.10.10.4 yamt
84 1.10.10.4 yamt return 0;
85 1.2 drochner }
86 1.1 drochner
87 1.10.10.2 yamt int
88 1.10.10.2 yamt acpitimer_detach(void)
89 1.10.10.2 yamt {
90 1.10.10.4 yamt
91 1.10.10.2 yamt return tc_detach(&acpi_timecounter);
92 1.10.10.2 yamt }
93 1.10.10.2 yamt
94 1.10.10.4 yamt u_int
95 1.8 christos acpitimer_read_fast(struct timecounter *tc)
96 1.2 drochner {
97 1.2 drochner uint32_t t;
98 1.2 drochner
99 1.10.10.4 yamt (void)AcpiGetTimer(&t);
100 1.10.10.4 yamt
101 1.10.10.4 yamt return t;
102 1.1 drochner }
103 1.1 drochner
104 1.1 drochner /*
105 1.10.10.4 yamt * Some chipsets (PIIX4 variants) do not latch correctly;
106 1.10.10.4 yamt * there is a chance that a transition is hit.
107 1.1 drochner */
108 1.10.10.4 yamt u_int
109 1.8 christos acpitimer_read_safe(struct timecounter *tc)
110 1.1 drochner {
111 1.1 drochner uint32_t t1, t2, t3;
112 1.1 drochner
113 1.10.10.4 yamt (void)AcpiGetTimer(&t2);
114 1.10.10.4 yamt (void)AcpiGetTimer(&t3);
115 1.10.10.4 yamt
116 1.1 drochner do {
117 1.1 drochner t1 = t2;
118 1.1 drochner t2 = t3;
119 1.10.10.4 yamt
120 1.10.10.4 yamt (void)AcpiGetTimer(&t3);
121 1.10.10.4 yamt
122 1.1 drochner } while ((t1 > t2) || (t2 > t3));
123 1.10.10.4 yamt
124 1.10.10.4 yamt return t2;
125 1.1 drochner }
126 1.1 drochner
127 1.10.10.4 yamt uint32_t
128 1.2 drochner acpitimer_delta(uint32_t end, uint32_t start)
129 1.2 drochner {
130 1.10.10.4 yamt const u_int mask = acpi_timecounter.tc_counter_mask;
131 1.2 drochner uint32_t delta;
132 1.2 drochner
133 1.2 drochner if (end >= start)
134 1.2 drochner delta = end - start;
135 1.2 drochner else
136 1.2 drochner delta = ((mask - start) + end + 1) & mask;
137 1.2 drochner
138 1.10.10.4 yamt return delta;
139 1.2 drochner }
140 1.2 drochner
141 1.2 drochner #define N 2000
142 1.10.10.4 yamt
143 1.2 drochner static int
144 1.10.10.2 yamt acpitimer_test(void)
145 1.2 drochner {
146 1.2 drochner uint32_t last, this, delta;
147 1.2 drochner int minl, maxl, n;
148 1.2 drochner
149 1.2 drochner minl = 10000000;
150 1.2 drochner maxl = 0;
151 1.2 drochner
152 1.10.10.2 yamt acpi_md_OsDisableInterrupt();
153 1.10.10.4 yamt
154 1.10.10.4 yamt (void)AcpiGetTimer(&last);
155 1.10.10.4 yamt
156 1.2 drochner for (n = 0; n < N; n++) {
157 1.10.10.4 yamt
158 1.10.10.4 yamt (void)AcpiGetTimer(&this);
159 1.10.10.4 yamt
160 1.2 drochner delta = acpitimer_delta(this, last);
161 1.10.10.4 yamt
162 1.2 drochner if (delta > maxl)
163 1.2 drochner maxl = delta;
164 1.2 drochner else if (delta < minl)
165 1.2 drochner minl = delta;
166 1.10.10.4 yamt
167 1.2 drochner last = this;
168 1.2 drochner }
169 1.10.10.4 yamt
170 1.10.10.2 yamt acpi_md_OsEnableInterrupt();
171 1.2 drochner
172 1.2 drochner if (maxl - minl > 2 )
173 1.2 drochner n = 0;
174 1.2 drochner else if (minl < 0 || maxl == 0)
175 1.2 drochner n = 0;
176 1.2 drochner else
177 1.2 drochner n = 1;
178 1.2 drochner
179 1.10.10.4 yamt return n;
180 1.2 drochner }
181