1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2019 Ruslan Bukin <br@bsdpad.com>
5 *
6 * This software was developed by SRI International and the University of
7 * Cambridge Computer Laboratory (Department of Computer Science and
8 * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
9 * DARPA SSITH research programme.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
38 #include <sys/rman.h>
39
40 #include <machine/bus.h>
41
42 #include <dev/fdt/simplebus.h>
43 #include <dev/fdt/fdt_common.h>
44 #include <dev/ofw/ofw_bus_subr.h>
45
46 #include "dwgpio_if.h"
47
48 struct dwgpiobus_softc {
49 struct simplebus_softc simplebus_sc;
50 device_t dev;
51 struct resource *res[1];
52 };
53
54 static struct resource_spec dwgpio_spec[] = {
55 { SYS_RES_MEMORY, 0, RF_ACTIVE },
56 { -1, 0 }
57 };
58
59 static int
dwgpiobus_probe(device_t dev)60 dwgpiobus_probe(device_t dev)
61 {
62
63 if (!ofw_bus_is_compatible(dev, "snps,dw-apb-gpio"))
64 return (ENXIO);
65
66 if (!ofw_bus_status_okay(dev))
67 return (ENXIO);
68
69 device_set_desc(dev, "Synopsys® DesignWare® APB GPIO BUS");
70
71 return (BUS_PROBE_DEFAULT);
72 }
73
74 static int
dwgpiobus_attach(device_t dev)75 dwgpiobus_attach(device_t dev)
76 {
77 struct dwgpiobus_softc *sc;
78 phandle_t node;
79
80 sc = device_get_softc(dev);
81 sc->dev = dev;
82
83 node = ofw_bus_get_node(dev);
84 if (node == -1)
85 return (ENXIO);
86
87 if (bus_alloc_resources(dev, dwgpio_spec, sc->res)) {
88 device_printf(dev, "Could not allocate resources.\n");
89 return (ENXIO);
90 }
91
92 simplebus_init(dev, node);
93
94 /*
95 * Allow devices to identify.
96 */
97 bus_generic_probe(dev);
98
99 /*
100 * Now walk the OFW tree and attach top-level devices.
101 */
102 for (node = OF_child(node); node > 0; node = OF_peer(node))
103 simplebus_add_device(dev, node, 0, NULL, -1, NULL);
104
105 return (bus_generic_attach(dev));
106 }
107
108 static int
dwgpiobus_detach(device_t dev)109 dwgpiobus_detach(device_t dev)
110 {
111 struct dwgpiobus_softc *sc;
112
113 sc = device_get_softc(dev);
114
115 bus_release_resources(dev, dwgpio_spec, sc->res);
116
117 return (0);
118 }
119
120 static int
dwgpiobus_write(device_t dev,bus_size_t offset,int val)121 dwgpiobus_write(device_t dev, bus_size_t offset, int val)
122 {
123 struct dwgpiobus_softc *sc;
124
125 sc = device_get_softc(dev);
126
127 bus_write_4(sc->res[0], offset, val);
128
129 return (0);
130 };
131
132 static int
dwgpiobus_read(device_t dev,bus_size_t offset)133 dwgpiobus_read(device_t dev, bus_size_t offset)
134 {
135 struct dwgpiobus_softc *sc;
136 int val;
137
138 sc = device_get_softc(dev);
139
140 val = bus_read_4(sc->res[0], offset);
141
142 return (val);
143 };
144
145 static device_method_t dwgpiobus_methods[] = {
146 DEVMETHOD(device_probe, dwgpiobus_probe),
147 DEVMETHOD(device_attach, dwgpiobus_attach),
148 DEVMETHOD(device_detach, dwgpiobus_detach),
149
150 DEVMETHOD(dwgpio_write, dwgpiobus_write),
151 DEVMETHOD(dwgpio_read, dwgpiobus_read),
152
153 DEVMETHOD_END
154 };
155
156 DEFINE_CLASS_1(dwgpiobus, dwgpiobus_driver, dwgpiobus_methods,
157 sizeof(struct dwgpiobus_softc), simplebus_driver);
158
159 EARLY_DRIVER_MODULE(dwgpiobus, simplebus, dwgpiobus_driver, 0, 0,
160 BUS_PASS_INTERRUPT + BUS_PASS_ORDER_MIDDLE);
161 MODULE_VERSION(dwgpiobus, 1);
162