1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
5 * Copyright (c) 2020 Jessica Clarke <jrtc27@FreeBSD.org>
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 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
26 * SUCH DAMAGE.
27 */
28
29 /*
30 * RISC-V syscon driver. Used as a generic interface by QEMU's virt machine for
31 * describing the SiFive test finisher as a power and reset controller.
32 */
33
34 #include <sys/param.h>
35 #include <sys/bus.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
38 #include <sys/mutex.h>
39 #include <sys/rman.h>
40 #include <machine/bus.h>
41
42 #include <dev/ofw/openfirm.h>
43 #include <dev/ofw/ofw_bus.h>
44 #include <dev/ofw/ofw_bus_subr.h>
45
46 #include <dev/syscon/syscon.h>
47 #include <dev/syscon/syscon_generic.h>
48
49 static struct ofw_compat_data compat_data[] = {
50 {"sifive,test0", 1},
51 {"sifive,test1", 1},
52 {NULL, 0}
53 };
54
55 static int
riscv_syscon_probe(device_t dev)56 riscv_syscon_probe(device_t dev)
57 {
58
59 if (!ofw_bus_status_okay(dev))
60 return (ENXIO);
61 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
62 return (ENXIO);
63
64 device_set_desc(dev, "RISC-V syscon");
65 return (BUS_PROBE_DEFAULT);
66 }
67
68 static device_method_t riscv_syscon_methods[] = {
69 DEVMETHOD(device_probe, riscv_syscon_probe),
70
71 DEVMETHOD_END
72 };
73
74 DEFINE_CLASS_1(riscv_syscon, riscv_syscon_driver, riscv_syscon_methods,
75 sizeof(struct syscon_generic_softc), syscon_generic_driver);
76
77 /* riscv_syscon needs to attach prior to syscon_power */
78 EARLY_DRIVER_MODULE(riscv_syscon, simplebus, riscv_syscon_driver, 0, 0,
79 BUS_PASS_SCHEDULER + BUS_PASS_ORDER_LAST);
80 MODULE_VERSION(riscv_syscon, 1);
81