1 /*-
2 * Copyright (c) 2015 Oleksandr Tymoshenko <gonzo@freebsd.org>
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 AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, 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
27 #include <sys/cdefs.h>
28 /*
29 * System Reset Control for iMX6
30 */
31
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/bus.h>
37 #include <sys/rman.h>
38
39 #include <dev/ofw/ofw_bus.h>
40 #include <dev/ofw/ofw_bus_subr.h>
41
42 #include <machine/bus.h>
43
44 #include <arm/freescale/imx/imx6_src.h>
45
46 #define SRC_SCR 0
47 #define SW_IPU1_RST (1 << 3)
48
49 struct src_softc {
50 device_t dev;
51 struct resource *mem_res;
52 };
53
54 static struct src_softc *src_sc;
55
56 static inline uint32_t
RD4(struct src_softc * sc,bus_size_t off)57 RD4(struct src_softc *sc, bus_size_t off)
58 {
59
60 return (bus_read_4(sc->mem_res, off));
61 }
62
63 static inline void
WR4(struct src_softc * sc,bus_size_t off,uint32_t val)64 WR4(struct src_softc *sc, bus_size_t off, uint32_t val)
65 {
66
67 bus_write_4(sc->mem_res, off, val);
68 }
69
70 int
src_reset_ipu(void)71 src_reset_ipu(void)
72 {
73 uint32_t reg;
74 int timeout = 10000;
75
76 if (src_sc == NULL)
77 return (-1);
78
79 reg = RD4(src_sc, SRC_SCR);
80 reg |= SW_IPU1_RST;
81 WR4(src_sc, SRC_SCR, reg);
82
83 while (timeout-- > 0) {
84 reg = RD4(src_sc, SRC_SCR);
85 if (reg & SW_IPU1_RST)
86 DELAY(1);
87 else
88 break;
89 }
90
91 if (timeout < 0)
92 return (-1);
93 else
94 return (0);
95 }
96
97 static int
src_detach(device_t dev)98 src_detach(device_t dev)
99 {
100 struct src_softc *sc;
101
102 sc = device_get_softc(dev);
103
104 if (sc->mem_res != NULL)
105 bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
106
107 return (0);
108 }
109
110 static int
src_attach(device_t dev)111 src_attach(device_t dev)
112 {
113 struct src_softc *sc;
114 int err, rid;
115
116 sc = device_get_softc(dev);
117 err = 0;
118
119 /* Allocate bus_space resources. */
120 rid = 0;
121 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
122 RF_ACTIVE);
123 if (sc->mem_res == NULL) {
124 device_printf(dev, "Cannot allocate memory resources\n");
125 err = ENXIO;
126 goto out;
127 }
128
129 src_sc = sc;
130
131 err = 0;
132
133 out:
134
135 if (err != 0)
136 src_detach(dev);
137
138 return (err);
139 }
140
141 static int
src_probe(device_t dev)142 src_probe(device_t dev)
143 {
144
145 if ((ofw_bus_is_compatible(dev, "fsl,imx6q-src") == 0) &&
146 (ofw_bus_is_compatible(dev, "fsl,imx6-src") == 0))
147 return (ENXIO);
148
149 device_set_desc(dev, "Freescale i.MX6 System Reset Controller");
150
151 return (BUS_PROBE_DEFAULT);
152 }
153
154 static device_method_t src_methods[] = {
155 /* Device interface */
156 DEVMETHOD(device_probe, src_probe),
157 DEVMETHOD(device_attach, src_attach),
158 DEVMETHOD(device_detach, src_detach),
159
160 DEVMETHOD_END
161 };
162
163 static driver_t src_driver = {
164 "src",
165 src_methods,
166 sizeof(struct src_softc)
167 };
168
169 DRIVER_MODULE(src, simplebus, src_driver, 0, 0);
170