xref: /netbsd-src/sys/arch/arm/imx/imxclock.c (revision a536ee5124e62c9a0051a252f7833dc8f50f44c9)
1 /*	$NetBSD: imxclock.c,v 1.6 2012/05/20 14:08:18 matt Exp $ */
2 /*
3  * Copyright (c) 2009, 2010  Genetec corp.  All rights reserved.
4  * Written by Hashimoto Kenichi for Genetec corp.
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 GENETEC CORP. ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL GENETEC CORP.
19  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 /*
29  * common part for i.MX31 and i.MX51
30  */
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/evcnt.h>
36 #include <sys/atomic.h>
37 #include <sys/time.h>
38 #include <sys/timetc.h>
39 
40 #include <sys/types.h>
41 #include <sys/device.h>
42 
43 #include <machine/intr.h>
44 #include <sys/bus.h>
45 
46 #include <arm/cpu.h>
47 #include <arm/armreg.h>
48 #include <arm/cpufunc.h>
49 
50 #include <arm/imx/imxclockvar.h>
51 #include <arm/imx/imxepitreg.h>
52 
53 static u_int imx_epit_get_timecount(struct timecounter *);
54 static int imxclock_intr(void *);
55 
56 static struct timecounter imx_epit_timecounter = {
57 	imx_epit_get_timecount,	/* get_timecount */
58 	0,			/* no poll_pps */
59 	0xffffffff,		/* counter_mask */
60 	0,			/* frequency */
61 	"epit",			/* name */
62 	100,			/* quality */
63 	NULL,			/* prev */
64 	NULL,			/* next */
65 };
66 
67 static volatile uint32_t imxclock_base;
68 
69 void
70 cpu_initclocks(void)
71 {
72 	uint32_t reg;
73 	u_int freq;
74 
75 	if (!epit1_sc) {
76 		panic("%s: driver has not been initialized!", __FUNCTION__);
77 	}
78 
79 	freq = imxclock_get_timerfreq(epit1_sc);
80 	imx_epit_timecounter.tc_frequency = freq;
81 	tc_init(&imx_epit_timecounter);
82 
83 	aprint_verbose_dev(epit1_sc->sc_dev,
84 			   "timer clock frequency %d\n", freq);
85 
86 	epit1_sc->sc_reload_value = freq / hz - 1;
87 
88 	/* stop all timers */
89 	bus_space_write_4(epit1_sc->sc_iot, epit1_sc->sc_ioh, EPIT_EPITCR, 0);
90 	bus_space_write_4(epit2_sc->sc_iot, epit2_sc->sc_ioh, EPIT_EPITCR, 0);
91 
92 	aprint_normal("clock: hz=%d stathz = %d\n", hz, stathz);
93 
94 	bus_space_write_4(epit1_sc->sc_iot, epit1_sc->sc_ioh, EPIT_EPITLR,
95 			  epit1_sc->sc_reload_value);
96 	bus_space_write_4(epit1_sc->sc_iot, epit1_sc->sc_ioh, EPIT_EPITCMPR, 0);
97 
98 	reg = EPITCR_ENMOD | EPITCR_IOVW | EPITCR_RLD | epit1_sc->sc_clksrc;
99 	bus_space_write_4(epit1_sc->sc_iot, epit1_sc->sc_ioh,
100 	    EPIT_EPITCR, reg);
101 	reg |= EPITCR_EN | EPITCR_OCIEN | EPITCR_WAITEN | EPITCR_DOZEN |
102 		EPITCR_STOPEN;
103 	bus_space_write_4(epit1_sc->sc_iot, epit1_sc->sc_ioh,
104 	    EPIT_EPITCR, reg);
105 
106 	epit1_sc->sc_ih = intr_establish(epit1_sc->sc_intr, IPL_CLOCK,
107 	    IST_LEVEL, imxclock_intr, NULL);
108 }
109 
110 #if 0
111 void
112 microtime(struct timeval *tvp)
113 {
114 }
115 #endif
116 
117 void
118 setstatclockrate(int schz)
119 {
120 }
121 
122 static int
123 imxclock_intr(void *arg)
124 {
125 	struct imxclock_softc *sc = epit1_sc;
126 
127 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, EPIT_EPITSR, 1);
128 	atomic_add_32(&imxclock_base, sc->sc_reload_value);
129 
130 	hardclock((struct clockframe *)arg);
131 
132 	return 1;
133 }
134 
135 u_int
136 imx_epit_get_timecount(struct timecounter *tc)
137 {
138 	uint32_t counter;
139 	uint32_t base;
140 	u_int oldirqstate;
141 
142 	oldirqstate = disable_interrupts(I32_bit);
143 	counter = bus_space_read_4(epit1_sc->sc_iot, epit1_sc->sc_ioh, EPIT_EPITCNT);
144 	base = imxclock_base;
145 	restore_interrupts(oldirqstate);
146 
147 	return base - counter;
148 }
149