1 /* $NetBSD: syscon.c,v 1.5 2021/01/27 03:10:21 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: syscon.c,v 1.5 2021/01/27 03:10:21 thorpej Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/systm.h>
36 #include <sys/sysctl.h>
37 #include <sys/kmem.h>
38 #include <sys/gpio.h>
39
40 #include <dev/fdt/fdtvar.h>
41 #include <dev/fdt/syscon.h>
42
43 struct syscon_softc {
44 device_t sc_dev;
45 bus_space_tag_t sc_bst;
46 bus_space_handle_t sc_bsh;
47 kmutex_t sc_lock;
48
49 struct syscon sc_syscon;
50 };
51
52 static int syscon_match(device_t, cfdata_t, void *);
53 static void syscon_attach(device_t, device_t, void *);
54
55 static const struct device_compatible_entry compat_data[] = {
56 { .compat = "syscon" },
57 { .compat = "simple-mfd" },
58 DEVICE_COMPAT_EOL
59 };
60
61 CFATTACH_DECL_NEW(syscon, sizeof(struct syscon_softc),
62 syscon_match, syscon_attach, NULL, NULL);
63
64 static void
syscon_generic_lock(void * priv)65 syscon_generic_lock(void *priv)
66 {
67 struct syscon_softc * const sc = priv;
68
69 mutex_enter(&sc->sc_lock);
70 }
71
72 static void
syscon_generic_unlock(void * priv)73 syscon_generic_unlock(void *priv)
74 {
75 struct syscon_softc * const sc = priv;
76
77 mutex_exit(&sc->sc_lock);
78 }
79
80 static uint32_t
syscon_generic_read_4(void * priv,bus_size_t reg)81 syscon_generic_read_4(void *priv, bus_size_t reg)
82 {
83 struct syscon_softc * const sc = priv;
84
85 KASSERT(mutex_owned(&sc->sc_lock));
86
87 return bus_space_read_4(sc->sc_bst, sc->sc_bsh, reg);
88 }
89
90 static void
syscon_generic_write_4(void * priv,bus_size_t reg,uint32_t val)91 syscon_generic_write_4(void *priv, bus_size_t reg, uint32_t val)
92 {
93 struct syscon_softc * const sc = priv;
94
95 KASSERT(mutex_owned(&sc->sc_lock));
96
97 bus_space_write_4(sc->sc_bst, sc->sc_bsh, reg, val);
98 }
99
100 static int
syscon_match(device_t parent,cfdata_t cf,void * aux)101 syscon_match(device_t parent, cfdata_t cf, void *aux)
102 {
103 struct fdt_attach_args * const faa = aux;
104
105 return of_compatible_match(faa->faa_phandle, compat_data);
106 }
107
108 static void
syscon_attach(device_t parent,device_t self,void * aux)109 syscon_attach(device_t parent, device_t self, void *aux)
110 {
111 struct syscon_softc * const sc = device_private(self);
112 struct fdt_attach_args * const faa = aux;
113 const int phandle = faa->faa_phandle;
114 bus_addr_t addr;
115 bus_size_t size;
116 int child;
117
118 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
119 aprint_error(": couldn't get registers\n");
120 return;
121 }
122
123 sc->sc_dev = self;
124 sc->sc_bst = faa->faa_bst;
125 if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) {
126 aprint_error(": couldn't map registers\n");
127 return;
128 }
129 mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM);
130 sc->sc_syscon.priv = sc;
131 sc->sc_syscon.lock = syscon_generic_lock;
132 sc->sc_syscon.unlock = syscon_generic_unlock;
133 sc->sc_syscon.read_4 = syscon_generic_read_4;
134 sc->sc_syscon.write_4 = syscon_generic_write_4;
135
136 aprint_naive("\n");
137 aprint_normal(": System Controller Registers\n");
138
139 fdtbus_register_syscon(self, phandle, &sc->sc_syscon);
140
141 fdt_add_bus(self, phandle, faa);
142
143 child = of_find_firstchild_byname(phandle, "clocks");
144 if (child > 0)
145 fdt_add_bus(self, child, faa);
146 }
147