summaryrefslogtreecommitdiffstats
path: root/sys/arm/allwinner/aw_reset.c
blob: 3f56e9fdd167d60ecf7eb652cbfd541140872f08 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
/*-
 * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */

/*
 * Allwinner module software reset registers
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/rman.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <machine/bus.h>

#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include <dev/extres/hwreset/hwreset.h>

#include "hwreset_if.h"

#define	RESET_OFFSET(index)	((index / 32) * 4)
#define	RESET_SHIFT(index)	(index % 32)

static struct ofw_compat_data compat_data[] = {
	{ "allwinner,sun6i-a31-ahb1-reset",	1 },
	{ "allwinner,sun6i-a31-clock-reset",	1 },
	{ NULL,					0 }
};

struct aw_reset_softc {
	struct resource		*res;
	struct mtx		mtx;
};

static struct resource_spec aw_reset_spec[] = {
	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
	{ -1, 0 }
};

#define	RESET_READ(sc, reg)		bus_read_4((sc)->res, (reg))
#define	RESET_WRITE(sc, reg, val)	bus_write_4((sc)->res, (reg), (val))

static int
aw_reset_assert(device_t dev, intptr_t id, bool reset)
{
	struct aw_reset_softc *sc;
	uint32_t reg_value;

	sc = device_get_softc(dev);

	mtx_lock(&sc->mtx);
	reg_value = RESET_READ(sc, RESET_OFFSET(id));
	if (reset)
		reg_value &= ~(1 << RESET_SHIFT(id));
	else
		reg_value |= (1 << RESET_SHIFT(id));
	RESET_WRITE(sc, RESET_OFFSET(id), reg_value);
	mtx_unlock(&sc->mtx);

	return (0);
}

static int
aw_reset_is_asserted(device_t dev, intptr_t id, bool *reset)
{
	struct aw_reset_softc *sc;
	uint32_t reg_value;

	sc = device_get_softc(dev);

	mtx_lock(&sc->mtx);
	reg_value = RESET_READ(sc, RESET_OFFSET(id));
	mtx_unlock(&sc->mtx);

	*reset = (reg_value & (1 << RESET_SHIFT(id))) != 0 ? false : true;

	return (0);
}

static int
aw_reset_probe(device_t dev)
{
	if (!ofw_bus_status_okay(dev))
		return (ENXIO);

	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
		return (ENXIO);

	device_set_desc(dev, "Allwinner Module Resets");
	return (BUS_PROBE_DEFAULT);
}

static int
aw_reset_attach(device_t dev)
{
	struct aw_reset_softc *sc;

	sc = device_get_softc(dev);

	if (bus_alloc_resources(dev, aw_reset_spec, &sc->res) != 0) {
		device_printf(dev, "cannot allocate resources for device\n");
		return (ENXIO);
	}

	mtx_init(&sc->mtx, device_get_nameunit(dev), NULL, MTX_DEF);

	hwreset_register_ofw_provider(dev);

	return (0);
}

static device_method_t aw_reset_methods[] = {
	/* Device interface */
	DEVMETHOD(device_probe,		aw_reset_probe),
	DEVMETHOD(device_attach,	aw_reset_attach),

	/* Reset interface */
	DEVMETHOD(hwreset_assert,	aw_reset_assert),
	DEVMETHOD(hwreset_is_asserted,	aw_reset_is_asserted),

	DEVMETHOD_END
};

static driver_t aw_reset_driver = {
	"aw_reset",
	aw_reset_methods,
	sizeof(struct aw_reset_softc),
};

static devclass_t aw_reset_devclass;

EARLY_DRIVER_MODULE(aw_reset, simplebus, aw_reset_driver, aw_reset_devclass,
    0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
MODULE_VERSION(aw_reset, 1);
OpenPOWER on IntegriCloud