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
43struct 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
52static int	syscon_match(device_t, cfdata_t, void *);
53static void	syscon_attach(device_t, device_t, void *);
54
55static const struct device_compatible_entry compat_data[] = {
56	{ .compat = "syscon" },
57	{ .compat = "simple-mfd" },
58	DEVICE_COMPAT_EOL
59};
60
61CFATTACH_DECL_NEW(syscon, sizeof(struct syscon_softc),
62	syscon_match, syscon_attach, NULL, NULL);
63
64static void
65syscon_generic_lock(void *priv)
66{
67	struct syscon_softc * const sc = priv;
68
69	mutex_enter(&sc->sc_lock);
70}
71
72static void
73syscon_generic_unlock(void *priv)
74{
75	struct syscon_softc * const sc = priv;
76
77	mutex_exit(&sc->sc_lock);
78}
79
80static uint32_t
81syscon_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
90static void
91syscon_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
100static int
101syscon_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
108static void
109syscon_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