1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2020 Andrew Turner
5 *
6 * This work was supported by Innovate UK project 105694, "Digital Security
7 * by Design (DSbD) Technology Platform Prototype".
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/sysctl.h>
37
38 #include <dev/fdt/simplebus.h>
39
40 #include <dev/ofw/ofw_bus.h>
41 #include <dev/ofw/ofw_bus_subr.h>
42
43 #include <arm/broadcom/bcm2835/bcm2835_firmware.h>
44 #include <arm/broadcom/bcm2835/bcm2835_mbox.h>
45 #include <arm/broadcom/bcm2835/bcm2835_mbox_prop.h>
46 #include <arm/broadcom/bcm2835/bcm2835_vcbus.h>
47
48 struct bcm2835_firmware_softc {
49 struct simplebus_softc sc;
50 phandle_t sc_mbox;
51 };
52
53 static struct ofw_compat_data compat_data[] = {
54 {"raspberrypi,bcm2835-firmware", 1},
55 {NULL, 0}
56 };
57
58 static int sysctl_bcm2835_firmware_get_revision(SYSCTL_HANDLER_ARGS);
59
60 static int
bcm2835_firmware_probe(device_t dev)61 bcm2835_firmware_probe(device_t dev)
62 {
63 if (!ofw_bus_status_okay(dev))
64 return (ENXIO);
65
66 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
67 return (ENXIO);
68
69 device_set_desc(dev, "BCM2835 Firmware");
70 return (BUS_PROBE_DEFAULT);
71 }
72
73 static int
bcm2835_firmware_attach(device_t dev)74 bcm2835_firmware_attach(device_t dev)
75 {
76 struct bcm2835_firmware_softc *sc;
77 struct sysctl_ctx_list *ctx;
78 struct sysctl_oid *tree_node;
79 struct sysctl_oid_list *tree;
80 phandle_t node, mbox;
81 int rv;
82
83 sc = device_get_softc(dev);
84
85 node = ofw_bus_get_node(dev);
86 rv = OF_getencprop(node, "mboxes", &mbox, sizeof(mbox));
87 if (rv <= 0) {
88 device_printf(dev, "can't read mboxes property\n");
89 return (ENXIO);
90 }
91 sc->sc_mbox = mbox;
92
93 OF_device_register_xref(OF_xref_from_node(node), dev);
94
95 ctx = device_get_sysctl_ctx(dev);
96 tree_node = device_get_sysctl_tree(dev);
97 tree = SYSCTL_CHILDREN(tree_node);
98 SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "revision",
99 CTLTYPE_UINT | CTLFLAG_RD, sc, sizeof(*sc),
100 sysctl_bcm2835_firmware_get_revision, "IU",
101 "Firmware revision");
102
103 /* The firmwaare doesn't have a ranges property */
104 sc->sc.flags |= SB_FLAG_NO_RANGES;
105 return (simplebus_attach(dev));
106 }
107
108 int
bcm2835_firmware_property(device_t dev,uint32_t prop,void * data,size_t len)109 bcm2835_firmware_property(device_t dev, uint32_t prop, void *data, size_t len)
110 {
111 struct {
112 struct bcm2835_mbox_hdr hdr;
113 struct bcm2835_mbox_tag_hdr tag_hdr;
114 uint32_t data[];
115 } *msg_hdr;
116 size_t msg_len;
117 int err;
118
119 /*
120 * The message is processed in 32-bit chunks so must be a multiple
121 * of 32-bits.
122 */
123 if ((len & (sizeof(uint32_t) - 1)) != 0)
124 return (EINVAL);
125
126 msg_len = sizeof(*msg_hdr) + len + sizeof(uint32_t);
127 msg_hdr = malloc(sizeof(*msg_hdr) + msg_len + sizeof(uint32_t),
128 M_DEVBUF, M_WAITOK | M_ZERO);
129
130 msg_hdr->hdr.buf_size = msg_len;
131 msg_hdr->hdr.code = BCM2835_MBOX_CODE_REQ;
132 msg_hdr->tag_hdr.tag = prop;
133 msg_hdr->tag_hdr.val_buf_size = len;
134 memcpy(msg_hdr->data, data, len);
135 msg_hdr->data[len / sizeof(uint32_t)] = 0;
136
137 err = bcm2835_mbox_property(msg_hdr, msg_len);
138 if (err == 0) {
139 memcpy(data, msg_hdr->data, len);
140 }
141
142 free(msg_hdr, M_DEVBUF);
143
144 return (err);
145 }
146
147 static int
sysctl_bcm2835_firmware_get_revision(SYSCTL_HANDLER_ARGS)148 sysctl_bcm2835_firmware_get_revision(SYSCTL_HANDLER_ARGS)
149 {
150 struct bcm2835_firmware_softc *sc = arg1;
151 uint32_t rev;
152 int err;
153
154 if (bcm2835_firmware_property(sc->sc.dev,
155 BCM2835_MBOX_TAG_FIRMWARE_REVISION, &rev, sizeof(rev)) != 0)
156 return (ENXIO);
157
158 err = sysctl_handle_int(oidp, &rev, sizeof(rev), req);
159 if (err || !req->newptr) /* error || read request */
160 return (err);
161
162 /* write request */
163 return (EINVAL);
164 }
165
166 static device_method_t bcm2835_firmware_methods[] = {
167 /* Device interface */
168 DEVMETHOD(device_probe, bcm2835_firmware_probe),
169 DEVMETHOD(device_attach, bcm2835_firmware_attach),
170
171 DEVMETHOD_END
172 };
173
174 DEFINE_CLASS_1(bcm2835_firmware, bcm2835_firmware_driver,
175 bcm2835_firmware_methods, sizeof(struct bcm2835_firmware_softc),
176 simplebus_driver);
177
178 EARLY_DRIVER_MODULE(bcm2835_firmware, simplebus, bcm2835_firmware_driver, 0, 0,
179 BUS_PASS_BUS + BUS_PASS_ORDER_LATE);
180 MODULE_DEPEND(bcm2835_firmware, mbox, 1, 1, 1);
181