1 /*-
2 * Copyright (c) 2002 by Thomas Moestl <tmm@FreeBSD.org>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
18 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
20 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
21 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
22 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
23 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * $FreeBSD: releng/5.2/sys/sparc64/sparc64/counter.c 111119 2003-02-19 05:47:46Z imp $
26 */
27
28 #include <sys/param.h>
29 #include <sys/bus.h>
30 #include <sys/malloc.h>
31 #include <sys/systm.h>
32 #include <sys/time.h>
33 #include <sys/timetc.h>
34
35 #include <machine/bus.h>
36 #include <machine/bus_common.h>
37
38 #define COUNTER_MASK ((1 << 29) - 1)
39 #define COUNTER_FREQ 1000000
40
41 /* Bits in the limit register. */
42 #define CTLR_INTEN (1U << 31) /* Enable timer interrupts */
43 #define CTLR_RELOAD (1U << 30) /* Zero counter on write to limit reg */
44 #define CTLR_PERIODIC (1U << 29) /* Wrap to 0 if limit is reached */
45
46 /* Offsets of the registers for the two counters. */
47 #define CTR_CT0 0x00
48 #define CTR_CT1 0x10
49
50 /* Register offsets from the base address. */
51 #define CTR_COUNT 0x00
52 #define CTR_LIMIT 0x08
53
54
55 static unsigned counter_get_timecount(struct timecounter *tc);
56
57 struct ct_softc {
58 bus_space_tag_t sc_tag;
59 bus_space_handle_t sc_handle;
60 bus_addr_t sc_offset;
61 };
62
63
64 /*
65 * This is called from the psycho and sbus drivers. It does not directly attach
66 * to the nexus because it shares register space with the bridge in question.
67 */
68 void
69 sparc64_counter_init(bus_space_tag_t tag, bus_space_handle_t handle,
70 bus_addr_t offset)
71 {
72 struct timecounter *tc;
73 struct ct_softc *sc;
74
75 printf("initialializing counter-timer\n");
76 /*
77 * Turn off interrupts from both counters. Set the limit to the maximum
78 * value (although that should not change anything with CTLR_INTEN and
79 * CTLR_PERIODIC off).
80 */
81 bus_space_write_8(tag, handle, offset + CTR_CT0 + CTR_LIMIT
82 , COUNTER_MASK);
83 bus_space_write_8(tag, handle, offset + CTR_CT1 + CTR_LIMIT,
84 COUNTER_MASK);
85 /* Register as a time counter. */
86 tc = malloc(sizeof(*tc), M_DEVBUF, M_WAITOK);
87 sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK);
88 sc->sc_tag = tag;
89 sc->sc_handle = handle;
90 sc->sc_offset = offset + CTR_CT0;
91 tc->tc_get_timecount = counter_get_timecount;
92 tc->tc_poll_pps = NULL;
93 tc->tc_counter_mask = COUNTER_MASK;
94 tc->tc_frequency = COUNTER_FREQ;
95 tc->tc_name = "counter-timer";
96 tc->tc_priv = sc;
97 tc_init(tc);
98 }
99
100 static unsigned
101 counter_get_timecount(struct timecounter *tc)
102 {
103 struct ct_softc *sc;
104
105 sc = tc->tc_priv;
106 return (bus_space_read_8(sc->sc_tag, sc->sc_handle, sc->sc_offset) &
107 COUNTER_MASK);
108 }
109
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