1 /*-
2 * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
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 BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
19 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
21 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
22 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: stable/12/sys/arm/allwinner/aw_reset.c 355174 2019-11-28 17:30:16Z manu $
27 */
28
29 /*
30 * Allwinner module software reset registers
31 */
32
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD: stable/12/sys/arm/allwinner/aw_reset.c 355174 2019-11-28 17:30:16Z manu $");
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 #include <sys/rman.h>
40 #include <sys/kernel.h>
41 #include <sys/module.h>
42 #include <machine/bus.h>
43
44 #include <dev/ofw/ofw_bus.h>
45 #include <dev/ofw/ofw_bus_subr.h>
46
47 #include <dev/extres/hwreset/hwreset.h>
48
49 #include "hwreset_if.h"
50
51 #define RESET_OFFSET(index) ((index / 32) * 4)
52 #define RESET_SHIFT(index) (index % 32)
53
54 static struct ofw_compat_data compat_data[] = {
55 { "allwinner,sun6i-a31-ahb1-reset", 1 },
56 { "allwinner,sun6i-a31-clock-reset", 1 },
57 { NULL, 0 }
58 };
59
60 struct aw_reset_softc {
61 struct resource *res;
62 struct mtx mtx;
63 };
64
65 static struct resource_spec aw_reset_spec[] = {
66 { SYS_RES_MEMORY, 0, RF_ACTIVE },
67 { -1, 0 }
68 };
69
70 #define RESET_READ(sc, reg) bus_read_4((sc)->res, (reg))
71 #define RESET_WRITE(sc, reg, val) bus_write_4((sc)->res, (reg), (val))
72
73 static int
aw_reset_assert(device_t dev,intptr_t id,bool reset)74 aw_reset_assert(device_t dev, intptr_t id, bool reset)
75 {
76 struct aw_reset_softc *sc;
77 uint32_t reg_value;
78
79 sc = device_get_softc(dev);
80
81 mtx_lock(&sc->mtx);
82 reg_value = RESET_READ(sc, RESET_OFFSET(id));
83 if (reset)
84 reg_value &= ~(1 << RESET_SHIFT(id));
85 else
86 reg_value |= (1 << RESET_SHIFT(id));
87 RESET_WRITE(sc, RESET_OFFSET(id), reg_value);
88 mtx_unlock(&sc->mtx);
89
90 return (0);
91 }
92
93 static int
aw_reset_is_asserted(device_t dev,intptr_t id,bool * reset)94 aw_reset_is_asserted(device_t dev, intptr_t id, bool *reset)
95 {
96 struct aw_reset_softc *sc;
97 uint32_t reg_value;
98
99 sc = device_get_softc(dev);
100
101 mtx_lock(&sc->mtx);
102 reg_value = RESET_READ(sc, RESET_OFFSET(id));
103 mtx_unlock(&sc->mtx);
104
105 *reset = (reg_value & (1 << RESET_SHIFT(id))) != 0 ? false : true;
106
107 return (0);
108 }
109
110 static int
aw_reset_probe(device_t dev)111 aw_reset_probe(device_t dev)
112 {
113 if (!ofw_bus_status_okay(dev))
114 return (ENXIO);
115
116 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
117 return (ENXIO);
118
119 device_set_desc(dev, "Allwinner Module Resets");
120 return (BUS_PROBE_DEFAULT);
121 }
122
123 static int
aw_reset_attach(device_t dev)124 aw_reset_attach(device_t dev)
125 {
126 struct aw_reset_softc *sc;
127
128 sc = device_get_softc(dev);
129
130 if (bus_alloc_resources(dev, aw_reset_spec, &sc->res) != 0) {
131 device_printf(dev, "cannot allocate resources for device\n");
132 return (ENXIO);
133 }
134
135 mtx_init(&sc->mtx, device_get_nameunit(dev), NULL, MTX_DEF);
136
137 hwreset_register_ofw_provider(dev);
138
139 return (0);
140 }
141
142 static device_method_t aw_reset_methods[] = {
143 /* Device interface */
144 DEVMETHOD(device_probe, aw_reset_probe),
145 DEVMETHOD(device_attach, aw_reset_attach),
146
147 /* Reset interface */
148 DEVMETHOD(hwreset_assert, aw_reset_assert),
149 DEVMETHOD(hwreset_is_asserted, aw_reset_is_asserted),
150
151 DEVMETHOD_END
152 };
153
154 static driver_t aw_reset_driver = {
155 "aw_reset",
156 aw_reset_methods,
157 sizeof(struct aw_reset_softc),
158 };
159
160 static devclass_t aw_reset_devclass;
161
162 EARLY_DRIVER_MODULE(aw_reset, simplebus, aw_reset_driver, aw_reset_devclass,
163 0, 0, BUS_PASS_RESOURCE + BUS_PASS_ORDER_MIDDLE);
164 MODULE_VERSION(aw_reset, 1);
165