xref: /freebsd/sys/i386/bios/smapi.c (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/malloc.h>
33 
34 #include <sys/module.h>
35 #include <sys/bus.h>
36 #include <sys/conf.h>
37 
38 #include <machine/bus.h>
39 #include <machine/resource.h>
40 #include <sys/rman.h>
41 
42 /* And all this for BIOS_PADDRTOVADDR() */
43 #include <vm/vm.h>
44 #include <vm/vm_param.h>
45 #include <vm/pmap.h>
46 #include <machine/md_var.h>
47 #include <machine/pc/bios.h>
48 
49 #include <machine/smapi.h>
50 
51 #define	SMAPI_START	0xf0000
52 #define	SMAPI_STEP	0x10
53 #define	SMAPI_OFF	0
54 #define	SMAPI_LEN	4
55 #define	SMAPI_SIG	"$SMB"
56 
57 #define	RES2HDR(res)	((struct smapi_bios_header *)rman_get_virtual(res))
58 #define	ADDR2HDR(addr)	((struct smapi_bios_header *)BIOS_PADDRTOVADDR(addr))
59 
60 struct smapi_softc {
61 	struct cdev *		cdev;
62 	device_t		dev;
63 	struct resource *	res;
64 	int			rid;
65 
66 	u_int32_t		smapi32_entry;
67 
68 	struct smapi_bios_header *header;
69 };
70 
71 extern u_long smapi32_offset;
72 extern u_short smapi32_segment;
73 
74 static d_ioctl_t smapi_ioctl;
75 
76 static struct cdevsw smapi_cdevsw = {
77 	.d_version =	D_VERSION,
78 	.d_ioctl =	smapi_ioctl,
79 	.d_name =	"smapi",
80 	.d_flags =	D_NEEDGIANT,
81 };
82 
83 static void	smapi_identify(driver_t *, device_t);
84 static int	smapi_probe(device_t);
85 static int	smapi_attach(device_t);
86 static int	smapi_detach(device_t);
87 static int	smapi_modevent(module_t, int, void *);
88 
89 static int	smapi_header_cksum(struct smapi_bios_header *);
90 
91 extern int	smapi32(struct smapi_bios_parameter *,
92 		    struct smapi_bios_parameter *);
93 extern int	smapi32_new(u_long, u_short,
94 		    struct smapi_bios_parameter *,
95 		    struct smapi_bios_parameter *);
96 
97 static int
98 smapi_ioctl (struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
99 {
100 	struct smapi_softc *sc = dev->si_drv1;
101 	int error;
102 
103 	switch (cmd) {
104 	case SMAPIOGHEADER:
105 		bcopy((caddr_t)sc->header, data,
106 				sizeof(struct smapi_bios_header));
107 		error = 0;
108 		break;
109 	case SMAPIOCGFUNCTION:
110 		smapi32_offset = sc->smapi32_entry;
111 		error = smapi32((struct smapi_bios_parameter *)data,
112 				(struct smapi_bios_parameter *)data);
113 		break;
114 	default:
115 		error = ENOTTY;
116 	}
117 
118 	return (error);
119 }
120 
121 static int
122 smapi_header_cksum (struct smapi_bios_header *header)
123 {
124 	u_int8_t *ptr;
125 	u_int8_t cksum;
126 	int i;
127 
128 	ptr = (u_int8_t *)header;
129 	cksum = 0;
130 	for (i = 0; i < header->length; i++) {
131 		cksum += ptr[i];
132 	}
133 
134 	return (cksum);
135 }
136 
137 static void
138 smapi_identify (driver_t *driver, device_t parent)
139 {
140 	device_t child;
141 	u_int32_t addr;
142 	int length;
143 	int rid;
144 
145 	if (!device_is_alive(parent))
146 		return;
147 
148 	addr = bios_sigsearch(SMAPI_START, SMAPI_SIG, SMAPI_LEN,
149                               SMAPI_STEP, SMAPI_OFF);
150 	if (addr != 0) {
151 		rid = 0;
152 		length = ADDR2HDR(addr)->length;
153 
154 		child = BUS_ADD_CHILD(parent, 5, "smapi", -1);
155 		device_set_driver(child, driver);
156 		bus_set_resource(child, SYS_RES_MEMORY, rid, addr, length);
157 		device_set_desc(child, "SMAPI BIOS");
158 	}
159 
160 	return;
161 }
162 
163 static int
164 smapi_probe (device_t dev)
165 {
166 	struct resource *res;
167 	int rid;
168 	int error;
169 
170 	error = 0;
171 	rid = 0;
172 	res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
173 	if (res == NULL) {
174 		device_printf(dev, "Unable to allocate memory resource.\n");
175 		error = ENOMEM;
176 		goto bad;
177 	}
178 
179 	if (smapi_header_cksum(RES2HDR(res))) {
180 		device_printf(dev, "SMAPI header checksum failed.\n");
181 		error = ENXIO;
182 		goto bad;
183 	}
184 
185 bad:
186 	if (res)
187 		bus_release_resource(dev, SYS_RES_MEMORY, rid, res);
188 	return (error);
189 }
190 
191 static int
192 smapi_attach (device_t dev)
193 {
194 	struct make_dev_args args;
195 	struct smapi_softc *sc;
196 	int error;
197 
198 	sc = device_get_softc(dev);
199 	error = 0;
200 
201 	sc->dev = dev;
202 	sc->rid = 0;
203 	sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->rid,
204 		 RF_ACTIVE);
205 	if (sc->res == NULL) {
206 		device_printf(dev, "Unable to allocate memory resource.\n");
207 		error = ENOMEM;
208 		goto bad;
209 	}
210 	sc->header = (struct smapi_bios_header *)rman_get_virtual(sc->res);
211 	sc->smapi32_entry = (u_int32_t)BIOS_PADDRTOVADDR(
212 					sc->header->prot32_segment +
213 					sc->header->prot32_offset);
214 
215 	make_dev_args_init(&args);
216 	args.mda_devsw = &smapi_cdevsw;
217 	args.mda_uid = UID_ROOT;
218 	args.mda_gid = GID_WHEEL;
219 	args.mda_mode = 0600;
220 	args.mda_si_drv1 = sc;
221         error = make_dev_s(&args, &sc->cdev, "%s%d",
222 			smapi_cdevsw.d_name,
223 			device_get_unit(sc->dev));
224 	if (error != 0)
225 		goto bad;
226 
227 	device_printf(dev, "Version: %d.%02d, Length: %d, Checksum: 0x%02x\n",
228 		bcd2bin(sc->header->version_major),
229 		bcd2bin(sc->header->version_minor),
230 		sc->header->length,
231 		sc->header->checksum);
232 	device_printf(dev, "Information=0x%b\n",
233 		sc->header->information,
234 		"\020"
235 		"\001REAL_VM86"
236 		"\002PROTECTED_16"
237 		"\003PROTECTED_32");
238 
239 	if (bootverbose) {
240 		if (sc->header->information & SMAPI_REAL_VM86)
241 			device_printf(dev, "Real/VM86 mode: Segment 0x%04x, Offset 0x%04x\n",
242 				sc->header->real16_segment,
243 				sc->header->real16_offset);
244 		if (sc->header->information & SMAPI_PROT_16BIT)
245 			device_printf(dev, "16-bit Protected mode: Segment 0x%08x, Offset 0x%04x\n",
246 				sc->header->prot16_segment,
247 				sc->header->prot16_offset);
248 		if (sc->header->information & SMAPI_PROT_32BIT)
249 			device_printf(dev, "32-bit Protected mode: Segment 0x%08x, Offset 0x%08x\n",
250 				sc->header->prot32_segment,
251 				sc->header->prot32_offset);
252 	}
253 
254 	return (0);
255 bad:
256 	if (sc->res)
257 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid, sc->res);
258 	return (error);
259 }
260 
261 static int
262 smapi_detach (device_t dev)
263 {
264 	struct smapi_softc *sc;
265 
266 	sc = device_get_softc(dev);
267 
268 	destroy_dev(sc->cdev);
269 
270 	if (sc->res)
271 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid, sc->res);
272 
273 	return (0);
274 }
275 
276 static device_method_t smapi_methods[] = {
277 	/* Device interface */
278 	DEVMETHOD(device_identify,      smapi_identify),
279 	DEVMETHOD(device_probe,         smapi_probe),
280 	DEVMETHOD(device_attach,        smapi_attach),
281 	DEVMETHOD(device_detach,        smapi_detach),
282 	{ 0, 0 }
283 };
284 
285 static driver_t smapi_driver = {
286 	"smapi",
287 	smapi_methods,
288 	sizeof(struct smapi_softc),
289 };
290 
291 static int
292 smapi_modevent (module_t mod, int what, void *arg)
293 {
294 	device_t *	devs;
295 	int		count;
296 	int		i;
297 
298 	switch (what) {
299 	case MOD_LOAD:
300 		break;
301 	case MOD_UNLOAD:
302 		devclass_get_devices(devclass_find(smapi_driver.name), &devs,
303 		    &count);
304 		for (i = 0; i < count; i++) {
305 			device_delete_child(device_get_parent(devs[i]), devs[i]);
306 		}
307 		free(devs, M_TEMP);
308 		break;
309 	default:
310 		break;
311 	}
312 
313 	return (0);
314 }
315 
316 DRIVER_MODULE(smapi, nexus, smapi_driver, smapi_modevent, NULL);
317 MODULE_VERSION(smapi, 1);
318