xref: /freebsd/sys/i386/bios/smapi.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
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/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 
37 #include <sys/module.h>
38 #include <sys/bus.h>
39 #include <sys/conf.h>
40 
41 #include <machine/bus.h>
42 #include <machine/resource.h>
43 #include <sys/rman.h>
44 
45 /* And all this for BIOS_PADDRTOVADDR() */
46 #include <vm/vm.h>
47 #include <vm/vm_param.h>
48 #include <vm/pmap.h>
49 #include <machine/md_var.h>
50 #include <machine/pc/bios.h>
51 
52 #include <machine/smapi.h>
53 
54 #define	SMAPI_START	0xf0000
55 #define	SMAPI_STEP	0x10
56 #define	SMAPI_OFF	0
57 #define	SMAPI_LEN	4
58 #define	SMAPI_SIG	"$SMB"
59 
60 #define	RES2HDR(res)	((struct smapi_bios_header *)rman_get_virtual(res))
61 #define	ADDR2HDR(addr)	((struct smapi_bios_header *)BIOS_PADDRTOVADDR(addr))
62 
63 struct smapi_softc {
64 	struct cdev *		cdev;
65 	device_t		dev;
66 	struct resource *	res;
67 	int			rid;
68 
69 	u_int32_t		smapi32_entry;
70 
71 	struct smapi_bios_header *header;
72 };
73 
74 extern u_long smapi32_offset;
75 extern u_short smapi32_segment;
76 
77 static d_ioctl_t smapi_ioctl;
78 
79 static struct cdevsw smapi_cdevsw = {
80 	.d_version =	D_VERSION,
81 	.d_ioctl =	smapi_ioctl,
82 	.d_name =	"smapi",
83 	.d_flags =	D_NEEDGIANT,
84 };
85 
86 static void	smapi_identify(driver_t *, device_t);
87 static int	smapi_probe(device_t);
88 static int	smapi_attach(device_t);
89 static int	smapi_detach(device_t);
90 static int	smapi_modevent(module_t, int, void *);
91 
92 static int	smapi_header_cksum(struct smapi_bios_header *);
93 
94 extern int	smapi32(struct smapi_bios_parameter *,
95 		    struct smapi_bios_parameter *);
96 extern int	smapi32_new(u_long, u_short,
97 		    struct smapi_bios_parameter *,
98 		    struct smapi_bios_parameter *);
99 
100 static int
101 smapi_ioctl (struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
102 {
103 	struct smapi_softc *sc = dev->si_drv1;
104 	int error;
105 
106 	switch (cmd) {
107 	case SMAPIOGHEADER:
108 		bcopy((caddr_t)sc->header, data,
109 				sizeof(struct smapi_bios_header));
110 		error = 0;
111 		break;
112 	case SMAPIOCGFUNCTION:
113 		smapi32_offset = sc->smapi32_entry;
114 		error = smapi32((struct smapi_bios_parameter *)data,
115 				(struct smapi_bios_parameter *)data);
116 		break;
117 	default:
118 		error = ENOTTY;
119 	}
120 
121 	return (error);
122 }
123 
124 static int
125 smapi_header_cksum (struct smapi_bios_header *header)
126 {
127 	u_int8_t *ptr;
128 	u_int8_t cksum;
129 	int i;
130 
131 	ptr = (u_int8_t *)header;
132 	cksum = 0;
133 	for (i = 0; i < header->length; i++) {
134 		cksum += ptr[i];
135 	}
136 
137 	return (cksum);
138 }
139 
140 static void
141 smapi_identify (driver_t *driver, device_t parent)
142 {
143 	device_t child;
144 	u_int32_t addr;
145 	int length;
146 	int rid;
147 
148 	if (!device_is_alive(parent))
149 		return;
150 
151 	addr = bios_sigsearch(SMAPI_START, SMAPI_SIG, SMAPI_LEN,
152                               SMAPI_STEP, SMAPI_OFF);
153 	if (addr != 0) {
154 		rid = 0;
155 		length = ADDR2HDR(addr)->length;
156 
157 		child = BUS_ADD_CHILD(parent, 5, "smapi", -1);
158 		device_set_driver(child, driver);
159 		bus_set_resource(child, SYS_RES_MEMORY, rid, addr, length);
160 		device_set_desc(child, "SMAPI BIOS");
161 	}
162 
163 	return;
164 }
165 
166 static int
167 smapi_probe (device_t dev)
168 {
169 	struct resource *res;
170 	int rid;
171 	int error;
172 
173 	error = 0;
174 	rid = 0;
175 	res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
176 	if (res == NULL) {
177 		device_printf(dev, "Unable to allocate memory resource.\n");
178 		error = ENOMEM;
179 		goto bad;
180 	}
181 
182 	if (smapi_header_cksum(RES2HDR(res))) {
183 		device_printf(dev, "SMAPI header checksum failed.\n");
184 		error = ENXIO;
185 		goto bad;
186 	}
187 
188 bad:
189 	if (res)
190 		bus_release_resource(dev, SYS_RES_MEMORY, rid, res);
191 	return (error);
192 }
193 
194 static int
195 smapi_attach (device_t dev)
196 {
197 	struct make_dev_args args;
198 	struct smapi_softc *sc;
199 	int error;
200 
201 	sc = device_get_softc(dev);
202 	error = 0;
203 
204 	sc->dev = dev;
205 	sc->rid = 0;
206 	sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->rid,
207 		 RF_ACTIVE);
208 	if (sc->res == NULL) {
209 		device_printf(dev, "Unable to allocate memory resource.\n");
210 		error = ENOMEM;
211 		goto bad;
212 	}
213 	sc->header = (struct smapi_bios_header *)rman_get_virtual(sc->res);
214 	sc->smapi32_entry = (u_int32_t)BIOS_PADDRTOVADDR(
215 					sc->header->prot32_segment +
216 					sc->header->prot32_offset);
217 
218 	make_dev_args_init(&args);
219 	args.mda_devsw = &smapi_cdevsw;
220 	args.mda_uid = UID_ROOT;
221 	args.mda_gid = GID_WHEEL;
222 	args.mda_mode = 0600;
223 	args.mda_si_drv1 = sc;
224         error = make_dev_s(&args, &sc->cdev, "%s%d",
225 			smapi_cdevsw.d_name,
226 			device_get_unit(sc->dev));
227 	if (error != 0)
228 		goto bad;
229 
230 	device_printf(dev, "Version: %d.%02d, Length: %d, Checksum: 0x%02x\n",
231 		bcd2bin(sc->header->version_major),
232 		bcd2bin(sc->header->version_minor),
233 		sc->header->length,
234 		sc->header->checksum);
235 	device_printf(dev, "Information=0x%b\n",
236 		sc->header->information,
237 		"\020"
238 		"\001REAL_VM86"
239 		"\002PROTECTED_16"
240 		"\003PROTECTED_32");
241 
242 	if (bootverbose) {
243 		if (sc->header->information & SMAPI_REAL_VM86)
244 			device_printf(dev, "Real/VM86 mode: Segment 0x%04x, Offset 0x%04x\n",
245 				sc->header->real16_segment,
246 				sc->header->real16_offset);
247 		if (sc->header->information & SMAPI_PROT_16BIT)
248 			device_printf(dev, "16-bit Protected mode: Segment 0x%08x, Offset 0x%04x\n",
249 				sc->header->prot16_segment,
250 				sc->header->prot16_offset);
251 		if (sc->header->information & SMAPI_PROT_32BIT)
252 			device_printf(dev, "32-bit Protected mode: Segment 0x%08x, Offset 0x%08x\n",
253 				sc->header->prot32_segment,
254 				sc->header->prot32_offset);
255 	}
256 
257 	return (0);
258 bad:
259 	if (sc->res)
260 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid, sc->res);
261 	return (error);
262 }
263 
264 static int
265 smapi_detach (device_t dev)
266 {
267 	struct smapi_softc *sc;
268 
269 	sc = device_get_softc(dev);
270 
271 	destroy_dev(sc->cdev);
272 
273 	if (sc->res)
274 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid, sc->res);
275 
276 	return (0);
277 }
278 
279 static device_method_t smapi_methods[] = {
280 	/* Device interface */
281 	DEVMETHOD(device_identify,      smapi_identify),
282 	DEVMETHOD(device_probe,         smapi_probe),
283 	DEVMETHOD(device_attach,        smapi_attach),
284 	DEVMETHOD(device_detach,        smapi_detach),
285 	{ 0, 0 }
286 };
287 
288 static driver_t smapi_driver = {
289 	"smapi",
290 	smapi_methods,
291 	sizeof(struct smapi_softc),
292 };
293 
294 static int
295 smapi_modevent (module_t mod, int what, void *arg)
296 {
297 	device_t *	devs;
298 	int		count;
299 	int		i;
300 
301 	switch (what) {
302 	case MOD_LOAD:
303 		break;
304 	case MOD_UNLOAD:
305 		devclass_get_devices(devclass_find(smapi_driver.name), &devs,
306 		    &count);
307 		for (i = 0; i < count; i++) {
308 			device_delete_child(device_get_parent(devs[i]), devs[i]);
309 		}
310 		free(devs, M_TEMP);
311 		break;
312 	default:
313 		break;
314 	}
315 
316 	return (0);
317 }
318 
319 DRIVER_MODULE(smapi, nexus, smapi_driver, smapi_modevent, NULL);
320 MODULE_VERSION(smapi, 1);
321