imx23_digctl.c revision 1.1 
1/* $Id: imx23_digctl.c,v 1.1 2013/10/07 17:36:40 matt Exp $ */
2
3/*
4* Copyright (c) 2013 The NetBSD Foundation, Inc.
5* All rights reserved.
6*
7* This code is derived from software contributed to The NetBSD Foundation
8* by Petri Laakso.
9*
10* Redistribution and use in source and binary forms, with or without
11* modification, are permitted provided that the following conditions
12* are met:
13* 1. Redistributions of source code must retain the above copyright
14*    notice, this list of conditions and the following disclaimer.
15* 2. Redistributions in binary form must reproduce the above copyright
16*    notice, this list of conditions and the following disclaimer in the
17*    documentation and/or other materials provided with the distribution.
18*
19* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29* POSSIBILITY OF SUCH DAMAGE.
30*/
31
32#include <sys/param.h>
33#include <sys/types.h>
34#include <sys/bus.h>
35#include <sys/cdefs.h>
36#include <sys/device.h>
37#include <sys/errno.h>
38#include <sys/timetc.h>
39
40#include <arm/imx/imx23_digctlreg.h>
41#include <arm/imx/imx23_digctlvar.h>
42#include <arm/imx/imx23var.h>
43
44typedef struct digctl_softc {
45	device_t sc_dev;
46	bus_space_tag_t sc_iot;
47	bus_space_handle_t sc_hdl;
48} *digctl_softc_t;
49
50static int	digctl_match(device_t, cfdata_t, void *);
51static void	digctl_attach(device_t, device_t, void *);
52static int	digctl_activate(device_t, enum devact);
53
54static void     digctl_reset(struct digctl_softc *);
55static void     digctl_init(struct digctl_softc *);
56
57/* timecounter. */
58static u_int digctl_tc_get_timecount(struct timecounter *);
59
60static digctl_softc_t _sc = NULL;
61
62CFATTACH_DECL3_NEW(digctl,
63        sizeof(struct digctl_softc),
64        digctl_match,
65        digctl_attach,
66        NULL,
67        digctl_activate,
68        NULL,
69        NULL,
70        0
71);
72
73static struct timecounter tc_useconds;
74
75#define DCTL_RD(sc, reg)                                                 \
76        bus_space_read_4(sc->sc_iot, sc->sc_hdl, (reg))
77#define DCTL_WR(sc, reg, val)                                            \
78        bus_space_write_4(sc->sc_iot, sc->sc_hdl, (reg), (val))
79
80static int
81digctl_match(device_t parent, cfdata_t match, void *aux)
82{
83	struct apb_attach_args *aa = aux;
84
85	if ((aa->aa_addr == HW_DIGCTL_BASE) && (aa->aa_size == HW_DIGCTL_SIZE))
86		return 1;
87
88	return 0;
89}
90
91static void
92digctl_attach(device_t parent, device_t self, void *aux)
93{
94	struct digctl_softc *sc = device_private(self);
95	struct apb_attach_args *aa = aux;
96	static int digctl_attached = 0;
97
98	sc->sc_dev = self;
99	sc->sc_iot = aa->aa_iot;
100
101	if (digctl_attached) {
102		aprint_error_dev(sc->sc_dev, "already attached\n");
103		return;
104	}
105
106	if (bus_space_map(sc->sc_iot, aa->aa_addr, aa->aa_size, 0,
107	    &sc->sc_hdl))
108	{
109		aprint_error_dev(sc->sc_dev, "Unable to map bus space\n");
110		return;
111	}
112
113	digctl_reset(sc);
114	digctl_init(sc);
115
116	aprint_normal("\n");
117
118	/*
119	 * Setup timecounter to use digctl microseconds counter.
120	 */
121	tc_useconds.tc_get_timecount = digctl_tc_get_timecount;
122	tc_useconds.tc_poll_pps = NULL;
123	tc_useconds.tc_counter_mask = 0xffffffff; /* 32bit counter. */
124	tc_useconds.tc_frequency = 1000000;       /* @ 1MHz */
125	tc_useconds.tc_name = "digctl";
126	tc_useconds.tc_quality = 100;
127
128	/* Enable counter. */
129	DCTL_WR(sc, HW_DIGCTL_CTRL_CLR, HW_DIGCTL_CTRL_XTAL24M_GATE);
130
131	tc_init(&tc_useconds);
132
133	digctl_attached = 1;
134
135	return;
136}
137
138static int
139digctl_activate(device_t self, enum devact act)
140{
141
142	return EOPNOTSUPP;
143}
144
145/*
146 * Inspired by i.MX23 RM "39.3.10 Correct Way to Soft Reset a Block"
147 */
148static void
149digctl_reset(struct digctl_softc *sc)
150{
151        return;
152}
153
154static void
155digctl_init(struct digctl_softc *sc)
156{
157	_sc = sc;
158	return;
159}
160
161/*
162 * Control USB controller clocks.
163 */
164void
165digctl_usb_clkgate(int value)
166{
167	struct digctl_softc *sc = _sc;
168
169	if (sc == NULL) {
170		aprint_error("digctl is not initalized");
171		return;
172	}
173
174	if (value) {
175		/* Clocks OFF. */
176		DCTL_WR(sc, HW_DIGCTL_CTRL_SET, HW_DIGCTL_CTRL_USB_CLKGATE);
177	} else {
178		/* Clocks ON. */
179		DCTL_WR(sc, HW_DIGCTL_CTRL_CLR, HW_DIGCTL_CTRL_USB_CLKGATE);
180	}
181
182	return;
183}
184
185/*
186 *
187 */
188static u_int
189digctl_tc_get_timecount(struct timecounter *tc)
190{
191	struct digctl_softc *sc = _sc;
192	return DCTL_RD(sc, HW_DIGCTL_MICROSECONDS);
193}
194