2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2015 Michal Meloun
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, 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
30 * This is a generic syscon driver, whose purpose is to provide access to
31 * various unrelated bits packed in a single register space. It is usually used
32 * as a fallback to more specific driver, but works well enough for simple
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 #include <sys/param.h>
39 #include <sys/systm.h>
41 #include <sys/kernel.h>
43 #include <sys/module.h>
46 #include <machine/bus.h>
48 #include <dev/ofw/ofw_bus.h>
49 #include <dev/ofw/ofw_bus_subr.h>
51 #include "syscon_if.h"
53 #include "syscon_generic.h"
55 MALLOC_DECLARE(M_SYSCON);
57 static uint32_t syscon_generic_read_4(struct syscon *syscon, bus_size_t offset);
58 static int syscon_generic_write_4(struct syscon *syscon, bus_size_t offset,
60 static int syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset,
61 uint32_t clear_bits, uint32_t set_bits);
64 * Generic syscon driver (FDT)
66 static struct ofw_compat_data compat_data[] = {
71 #define SYSCON_LOCK(_sc) mtx_lock_spin(&(_sc)->mtx)
72 #define SYSCON_UNLOCK(_sc) mtx_unlock_spin(&(_sc)->mtx)
73 #define SYSCON_LOCK_INIT(_sc) mtx_init(&(_sc)->mtx, \
74 device_get_nameunit((_sc)->dev), "syscon", MTX_SPIN)
75 #define SYSCON_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->mtx);
76 #define SYSCON_ASSERT_LOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_OWNED);
77 #define SYSCON_ASSERT_UNLOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_NOTOWNED);
79 static syscon_method_t syscon_generic_methods[] = {
80 SYSCONMETHOD(syscon_read_4, syscon_generic_read_4),
81 SYSCONMETHOD(syscon_write_4, syscon_generic_write_4),
82 SYSCONMETHOD(syscon_modify_4, syscon_generic_modify_4),
86 DEFINE_CLASS_1(syscon_generic, syscon_generic_class, syscon_generic_methods,
90 syscon_generic_read_4(struct syscon *syscon, bus_size_t offset)
92 struct syscon_generic_softc *sc;
95 sc = device_get_softc(syscon->pdev);
98 val = bus_read_4(sc->mem_res, offset);
104 syscon_generic_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val)
106 struct syscon_generic_softc *sc;
108 sc = device_get_softc(syscon->pdev);
111 bus_write_4(sc->mem_res, offset, val);
117 syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset,
118 uint32_t clear_bits, uint32_t set_bits)
120 struct syscon_generic_softc *sc;
123 sc = device_get_softc(syscon->pdev);
126 val = bus_read_4(sc->mem_res, offset);
129 bus_write_4(sc->mem_res, offset, val);
135 syscon_generic_probe(device_t dev)
138 if (!ofw_bus_status_okay(dev))
140 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
143 device_set_desc(dev, "syscon");
144 return (BUS_PROBE_GENERIC);
148 syscon_generic_attach(device_t dev)
150 struct syscon_generic_softc *sc;
153 sc = device_get_softc(dev);
157 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
159 if (sc->mem_res == NULL) {
160 device_printf(dev, "Cannot allocate memory resource\n");
164 SYSCON_LOCK_INIT(sc);
165 sc->syscon = syscon_create_ofw_node(dev, &syscon_generic_class,
166 ofw_bus_get_node(dev));
167 if (sc->syscon == NULL) {
168 device_printf(dev, "Failed to create/register syscon\n");
175 syscon_generic_detach(device_t dev)
177 struct syscon_generic_softc *sc;
179 sc = device_get_softc(dev);
180 if (sc->syscon != NULL) {
181 syscon_unregister(sc->syscon);
182 free(sc->syscon, M_SYSCON);
185 SYSCON_LOCK_DESTROY(sc);
187 if (sc->mem_res != NULL)
188 bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
192 static device_method_t syscon_generic_dmethods[] = {
193 /* Device interface */
194 DEVMETHOD(device_probe, syscon_generic_probe),
195 DEVMETHOD(device_attach, syscon_generic_attach),
196 DEVMETHOD(device_detach, syscon_generic_detach),
201 DEFINE_CLASS_0(syscon_generic, syscon_generic_driver, syscon_generic_dmethods,
202 sizeof(struct syscon_generic_softc));
203 static devclass_t syscon_generic_devclass;
205 EARLY_DRIVER_MODULE(syscon_generic, simplebus, syscon_generic_driver,
206 syscon_generic_devclass, 0, 0, BUS_PASS_DEFAULT);
207 MODULE_VERSION(syscon_generic, 1);