1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2019 Axiado Corporation.
5 * All rights reserved.
6 *
7 * This software was developed in part by Philip Paeps under contract for
8 * Axiado Corporation.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright notice,
14 * this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
20 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
29 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/limits.h>
36 #include <sys/module.h>
37 #include <sys/bus.h>
38 #include <sys/lock.h>
39 #include <sys/mutex.h>
40 #include <sys/rman.h>
41
42 #include <dev/clk/clk.h>
43
44 #include <dev/iicbus/iicbus.h>
45 #include <dev/iicbus/iiconf.h>
46
47 #include <dev/ofw/ofw_bus.h>
48 #include <dev/ofw/ofw_bus_subr.h>
49
50 #include "iicbus_if.h"
51 #include "iicoc.h"
52
53 static struct ofw_compat_data compat_data[] = {
54 { "opencores,i2c-ocores", 1 },
55 { "sifive,fu740-c000-i2c", 1 },
56 { "sifive,fu540-c000-i2c", 1 },
57 { "sifive,i2c0", 1 },
58 { NULL, 0 }
59 };
60
61 static struct resource_spec iicoc_spec[] = {
62 { SYS_RES_MEMORY, 0, RF_ACTIVE },
63 RESOURCE_SPEC_END
64 };
65
66 static phandle_t
iicoc_get_node(device_t bus,device_t dev)67 iicoc_get_node(device_t bus, device_t dev)
68 {
69
70 /* Share controller node with iicbus device. */
71 return (ofw_bus_get_node(bus));
72 }
73
74 static int
iicoc_attach(device_t dev)75 iicoc_attach(device_t dev)
76 {
77 struct iicoc_softc *sc;
78 phandle_t node;
79 clk_t clock;
80 uint64_t clockfreq;
81 int error;
82
83 sc = device_get_softc(dev);
84 sc->dev = dev;
85
86 mtx_init(&sc->sc_mtx, "iicoc", "iicoc", MTX_DEF);
87
88 error = bus_alloc_resources(dev, iicoc_spec, &sc->mem_res);
89 if (error) {
90 device_printf(dev, "Could not allocate bus resource.\n");
91 goto fail;
92 }
93
94 node = ofw_bus_get_node(dev);
95 sc->reg_shift = 0;
96 OF_getencprop(node, "reg-shift", &sc->reg_shift,
97 sizeof(sc->reg_shift));
98
99 error = clk_get_by_ofw_index(dev, 0, 0, &clock);
100 if (error) {
101 device_printf(dev, "Couldn't get clock\n");
102 goto fail;
103 }
104 error = clk_enable(clock);
105 if (error) {
106 device_printf(dev, "Couldn't enable clock\n");
107 goto fail1;
108 }
109 error = clk_get_freq(clock, &clockfreq);
110 if (error) {
111 device_printf(dev, "Couldn't get clock frequency\n");
112 goto fail1;
113 }
114 if (clockfreq > UINT_MAX) {
115 device_printf(dev, "Unsupported clock frequency\n");
116 goto fail1;
117 }
118 sc->clockfreq = (u_int)clockfreq;
119 sc->i2cfreq = XLP_I2C_FREQ;
120 iicoc_init(dev);
121
122 sc->iicbus = device_add_child(dev, "iicbus", DEVICE_UNIT_ANY);
123 if (sc->iicbus == NULL) {
124 device_printf(dev, "Could not allocate iicbus instance.\n");
125 error = ENXIO;
126 goto fail1;
127 }
128
129 /* Probe and attach the iicbus when interrupts are available. */
130 bus_delayed_attach_children(dev);
131
132 return (0);
133
134 fail1:
135 clk_disable(clock);
136
137 fail:
138 bus_release_resources(dev, iicoc_spec, &sc->mem_res);
139 mtx_destroy(&sc->sc_mtx);
140 return (error);
141 }
142
143 static int
iicoc_probe(device_t dev)144 iicoc_probe(device_t dev)
145 {
146
147 if (!ofw_bus_status_okay(dev))
148 return (ENXIO);
149
150 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
151 return (ENXIO);
152
153 device_set_desc(dev, "OpenCores I2C master controller");
154
155 return (BUS_PROBE_DEFAULT);
156 }
157
158 static device_method_t iicoc_methods[] = {
159 /* device interface */
160 DEVMETHOD(device_probe, iicoc_probe),
161 DEVMETHOD(device_attach, iicoc_attach),
162
163 /* ofw interface */
164 DEVMETHOD(ofw_bus_get_node, iicoc_get_node),
165
166 /* iicbus interface */
167 DEVMETHOD(iicbus_callback, iicbus_null_callback),
168 DEVMETHOD(iicbus_repeated_start, iicoc_iicbus_repeated_start),
169 DEVMETHOD(iicbus_start, iicoc_iicbus_start),
170 DEVMETHOD(iicbus_stop, iicoc_iicbus_stop),
171 DEVMETHOD(iicbus_reset, iicoc_iicbus_reset),
172 DEVMETHOD(iicbus_write, iicoc_iicbus_write),
173 DEVMETHOD(iicbus_read, iicoc_iicbus_read),
174 DEVMETHOD(iicbus_transfer, iicbus_transfer_gen),
175
176 DEVMETHOD_END
177 };
178
179 static driver_t iicoc_driver = {
180 "iicoc",
181 iicoc_methods,
182 sizeof(struct iicoc_softc),
183 };
184
185 SIMPLEBUS_PNP_INFO(compat_data);
186 DRIVER_MODULE(iicoc, simplebus, iicoc_driver, 0, 0);
187 DRIVER_MODULE(ofw_iicbus, iicoc, ofw_iicbus_driver, 0, 0);
188 MODULE_DEPEND(iicoc, iicbus, 1, 1, 1);
189 MODULE_DEPEND(iicoc, ofw_iicbus, 1, 1, 1);
190