xref: /freebsd/sys/dev/smbios/smbios.c (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2003 Matthew N. Dodd <winter@jurai.net>
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 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 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/socket.h>
37 #include <sys/efi.h>
38 
39 #include <sys/module.h>
40 #include <sys/bus.h>
41 
42 #include <machine/bus.h>
43 #include <machine/resource.h>
44 #include <sys/rman.h>
45 
46 #include <vm/vm.h>
47 #include <vm/vm_param.h>
48 #include <vm/pmap.h>
49 #include <machine/md_var.h>
50 #if defined(__amd64__) || defined(__i386__)
51 #include <machine/pc/bios.h>
52 #endif
53 #include <dev/smbios/smbios.h>
54 
55 /*
56  * System Management BIOS Reference Specification, v2.4 Final
57  * http://www.dmtf.org/standards/published_documents/DSP0134.pdf
58  */
59 
60 struct smbios_softc {
61 	device_t		dev;
62 	struct resource *	res;
63 	int			rid;
64 
65 	struct smbios_eps *	eps;
66 };
67 
68 #define	RES2EPS(res)	((struct smbios_eps *)rman_get_virtual(res))
69 
70 static devclass_t	smbios_devclass;
71 
72 static void	smbios_identify	(driver_t *, device_t);
73 static int	smbios_probe	(device_t);
74 static int	smbios_attach	(device_t);
75 static int	smbios_detach	(device_t);
76 static int	smbios_modevent	(module_t, int, void *);
77 
78 static int	smbios_cksum	(struct smbios_eps *);
79 
80 static void
81 smbios_identify (driver_t *driver, device_t parent)
82 {
83 #ifdef ARCH_MAY_USE_EFI
84 	struct uuid efi_smbios = EFI_TABLE_SMBIOS;
85 	void *addr_efi;
86 #endif
87 	struct smbios_eps *eps;
88 	device_t child;
89 	vm_paddr_t addr = 0;
90 	int length;
91 	int rid;
92 
93 	if (!device_is_alive(parent))
94 		return;
95 
96 #ifdef ARCH_MAY_USE_EFI
97 	if (!efi_get_table(&efi_smbios, &addr_efi))
98 		addr = (vm_paddr_t)addr_efi;
99 #endif
100 
101 #if defined(__amd64__) || defined(__i386__)
102 	if (addr == 0)
103 		addr = bios_sigsearch(SMBIOS_START, SMBIOS_SIG, SMBIOS_LEN,
104 		    SMBIOS_STEP, SMBIOS_OFF);
105 #endif
106 
107 	if (addr != 0) {
108 		eps = pmap_mapbios(addr, 0x1f);
109 		rid = 0;
110 		length = eps->length;
111 
112 		if (length != 0x1f) {
113 			u_int8_t major, minor;
114 
115 			major = eps->major_version;
116 			minor = eps->minor_version;
117 
118 			/* SMBIOS v2.1 implementation might use 0x1e. */
119 			if (length == 0x1e && major == 2 && minor == 1)
120 				length = 0x1f;
121 			else
122 				return;
123 		}
124 
125 		child = BUS_ADD_CHILD(parent, 5, "smbios", -1);
126 		device_set_driver(child, driver);
127 		bus_set_resource(child, SYS_RES_MEMORY, rid, addr, length);
128 		device_set_desc(child, "System Management BIOS");
129 		pmap_unmapbios((vm_offset_t)eps, 0x1f);
130 	}
131 
132 	return;
133 }
134 
135 static int
136 smbios_probe (device_t dev)
137 {
138 	struct resource *res;
139 	int rid;
140 	int error;
141 
142 	error = 0;
143 	rid = 0;
144 	res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
145 	if (res == NULL) {
146 		device_printf(dev, "Unable to allocate memory resource.\n");
147 		error = ENOMEM;
148 		goto bad;
149 	}
150 
151 	if (smbios_cksum(RES2EPS(res))) {
152 		device_printf(dev, "SMBIOS checksum failed.\n");
153 		error = ENXIO;
154 		goto bad;
155 	}
156 
157 bad:
158 	if (res)
159 		bus_release_resource(dev, SYS_RES_MEMORY, rid, res);
160 	return (error);
161 }
162 
163 static int
164 smbios_attach (device_t dev)
165 {
166 	struct smbios_softc *sc;
167 	int error;
168 
169 	sc = device_get_softc(dev);
170 	error = 0;
171 
172 	sc->dev = dev;
173 	sc->rid = 0;
174 	sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->rid,
175 		RF_ACTIVE);
176 	if (sc->res == NULL) {
177 		device_printf(dev, "Unable to allocate memory resource.\n");
178 		error = ENOMEM;
179 		goto bad;
180 	}
181 	sc->eps = RES2EPS(sc->res);
182 
183 	device_printf(dev, "Version: %u.%u",
184 	    sc->eps->major_version, sc->eps->minor_version);
185 	if (bcd2bin(sc->eps->BCD_revision))
186 		printf(", BCD Revision: %u.%u",
187 			bcd2bin(sc->eps->BCD_revision >> 4),
188 			bcd2bin(sc->eps->BCD_revision & 0x0f));
189 	printf("\n");
190 
191 	return (0);
192 bad:
193 	if (sc->res)
194 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid, sc->res);
195 	return (error);
196 }
197 
198 static int
199 smbios_detach (device_t dev)
200 {
201 	struct smbios_softc *sc;
202 
203 	sc = device_get_softc(dev);
204 
205 	if (sc->res)
206 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid, sc->res);
207 
208 	return (0);
209 }
210 
211 static int
212 smbios_modevent (mod, what, arg)
213         module_t        mod;
214         int             what;
215         void *          arg;
216 {
217 	device_t *	devs;
218 	int		count;
219 	int		i;
220 
221 	switch (what) {
222 	case MOD_LOAD:
223 		break;
224 	case MOD_UNLOAD:
225 		devclass_get_devices(smbios_devclass, &devs, &count);
226 		for (i = 0; i < count; i++) {
227 			device_delete_child(device_get_parent(devs[i]), devs[i]);
228 		}
229 		free(devs, M_TEMP);
230 		break;
231 	default:
232 		break;
233 	}
234 
235 	return (0);
236 }
237 
238 static device_method_t smbios_methods[] = {
239 	/* Device interface */
240 	DEVMETHOD(device_identify,      smbios_identify),
241 	DEVMETHOD(device_probe,         smbios_probe),
242 	DEVMETHOD(device_attach,        smbios_attach),
243 	DEVMETHOD(device_detach,        smbios_detach),
244 	{ 0, 0 }
245 };
246 
247 static driver_t smbios_driver = {
248 	"smbios",
249 	smbios_methods,
250 	sizeof(struct smbios_softc),
251 };
252 
253 DRIVER_MODULE(smbios, nexus, smbios_driver, smbios_devclass, smbios_modevent, 0);
254 #ifdef ARCH_MAY_USE_EFI
255 MODULE_DEPEND(smbios, efirt, 1, 1, 1);
256 #endif
257 MODULE_VERSION(smbios, 1);
258 
259 static int
260 smbios_cksum (struct smbios_eps *e)
261 {
262 	u_int8_t *ptr;
263 	u_int8_t cksum;
264 	int i;
265 
266 	ptr = (u_int8_t *)e;
267 	cksum = 0;
268 	for (i = 0; i < e->length; i++) {
269 		cksum += ptr[i];
270 	}
271 
272 	return (cksum);
273 }
274