1/*-
2 * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
18 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
20 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
21 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 *
25 * $FreeBSD$
26 */
27
28/*
29 * Allwinner module software reset registers
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD$");
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/bus.h>
38#include <sys/rman.h>
39#include <sys/kernel.h>
40#include <sys/lock.h>
41#include <sys/module.h>
42#include <sys/mutex.h>
43#include <machine/bus.h>
44
45#include <dev/ofw/ofw_bus.h>
46#include <dev/ofw/ofw_bus_subr.h>
47
48#include <dev/extres/hwreset/hwreset.h>
49
50#include "hwreset_if.h"
51
52#define	RESET_OFFSET(index)	((index / 32) * 4)
53#define	RESET_SHIFT(index)	(index % 32)
54
55static struct ofw_compat_data compat_data[] = {
56	{ "allwinner,sun6i-a31-ahb1-reset",	1 },
57	{ "allwinner,sun6i-a31-clock-reset",	1 },
58	{ NULL,					0 }
59};
60
61struct aw_reset_softc {
62	struct resource		*res;
63	struct mtx		mtx;
64};
65
66static struct resource_spec aw_reset_spec[] = {
67	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
68	{ -1, 0 }
69};
70
71#define	RESET_READ(sc, reg)		bus_read_4((sc)->res, (reg))
72#define	RESET_WRITE(sc, reg, val)	bus_write_4((sc)->res, (reg), (val))
73
74static int
75aw_reset_assert(device_t dev, intptr_t id, bool reset)
76{
77	struct aw_reset_softc *sc;
78	uint32_t reg_value;
79
80	sc = device_get_softc(dev);
81
82	mtx_lock(&sc->mtx);
83	reg_value = RESET_READ(sc, RESET_OFFSET(id));
84	if (reset)
85		reg_value &= ~(1 << RESET_SHIFT(id));
86	else
87		reg_value |= (1 << RESET_SHIFT(id));
88	RESET_WRITE(sc, RESET_OFFSET(id), reg_value);
89	mtx_unlock(&sc->mtx);
90
91	return (0);
92}
93
94static int
95aw_reset_is_asserted(device_t dev, intptr_t id, bool *reset)
96{
97	struct aw_reset_softc *sc;
98	uint32_t reg_value;
99
100	sc = device_get_softc(dev);
101
102	mtx_lock(&sc->mtx);
103	reg_value = RESET_READ(sc, RESET_OFFSET(id));
104	mtx_unlock(&sc->mtx);
105
106	*reset = (reg_value & (1 << RESET_SHIFT(id))) != 0 ? false : true;
107
108	return (0);
109}
110
111static int
112aw_reset_probe(device_t dev)
113{
114	if (!ofw_bus_status_okay(dev))
115		return (ENXIO);
116
117	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
118		return (ENXIO);
119
120	device_set_desc(dev, "Allwinner Module Resets");
121	return (BUS_PROBE_DEFAULT);
122}
123
124static int
125aw_reset_attach(device_t dev)
126{
127	struct aw_reset_softc *sc;
128
129	sc = device_get_softc(dev);
130
131	if (bus_alloc_resources(dev, aw_reset_spec, &sc->res) != 0) {
132		device_printf(dev, "cannot allocate resources for device\n");
133		return (ENXIO);
134	}
135
136	mtx_init(&sc->mtx, device_get_nameunit(dev), NULL, MTX_DEF);
137
138	hwreset_register_ofw_provider(dev);
139
140	return (0);
141}
142
143static device_method_t aw_reset_methods[] = {
144	/* Device interface */
145	DEVMETHOD(device_probe,		aw_reset_probe),
146	DEVMETHOD(device_attach,	aw_reset_attach),
147
148	/* Reset interface */
149	DEVMETHOD(hwreset_assert,	aw_reset_assert),
150	DEVMETHOD(hwreset_is_asserted,	aw_reset_is_asserted),
151
152	DEVMETHOD_END
153};
154
155static driver_t aw_reset_driver = {
156	"aw_reset",
157	aw_reset_methods,
158	sizeof(struct aw_reset_softc),
159};
160
161static devclass_t aw_reset_devclass;
162
163EARLY_DRIVER_MODULE(aw_reset, simplebus, aw_reset_driver, aw_reset_devclass,
164    0, 0, BUS_PASS_RESOURCE + BUS_PASS_ORDER_MIDDLE);
165MODULE_VERSION(aw_reset, 1);
166