xref: /freebsd/sys/dev/pci/pci_user.c (revision 3642298923e528d795e3a30ec165d2b469e28b40)
1 /*-
2  * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_bus.h"	/* XXX trim includes */
31 #include "opt_compat.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/malloc.h>
36 #include <sys/module.h>
37 #include <sys/linker.h>
38 #include <sys/fcntl.h>
39 #include <sys/conf.h>
40 #include <sys/kernel.h>
41 #include <sys/proc.h>
42 #include <sys/queue.h>
43 #include <sys/types.h>
44 
45 #include <vm/vm.h>
46 #include <vm/pmap.h>
47 #include <vm/vm_extern.h>
48 
49 #include <sys/bus.h>
50 #include <machine/bus.h>
51 #include <sys/rman.h>
52 #include <machine/resource.h>
53 
54 #include <sys/pciio.h>
55 #include <dev/pci/pcireg.h>
56 #include <dev/pci/pcivar.h>
57 
58 #include "pcib_if.h"
59 #include "pci_if.h"
60 
61 /*
62  * This is the user interface to PCI configuration space.
63  */
64 
65 static d_open_t 	pci_open;
66 static d_close_t	pci_close;
67 static int	pci_conf_match(struct pci_match_conf *matches, int num_matches,
68 			       struct pci_conf *match_buf);
69 static d_ioctl_t	pci_ioctl;
70 
71 struct cdevsw pcicdev = {
72 	.d_version =	D_VERSION,
73 	.d_flags =	D_NEEDGIANT,
74 	.d_open =	pci_open,
75 	.d_close =	pci_close,
76 	.d_ioctl =	pci_ioctl,
77 	.d_name =	"pci",
78 };
79 
80 static int
81 pci_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
82 {
83 	int error;
84 
85 	if (oflags & FWRITE) {
86 		error = securelevel_gt(td->td_ucred, 0);
87 		if (error)
88 			return (error);
89 	}
90 
91 	return (0);
92 }
93 
94 static int
95 pci_close(struct cdev *dev, int flag, int devtype, struct thread *td)
96 {
97 	return 0;
98 }
99 
100 /*
101  * Match a single pci_conf structure against an array of pci_match_conf
102  * structures.  The first argument, 'matches', is an array of num_matches
103  * pci_match_conf structures.  match_buf is a pointer to the pci_conf
104  * structure that will be compared to every entry in the matches array.
105  * This function returns 1 on failure, 0 on success.
106  */
107 static int
108 pci_conf_match(struct pci_match_conf *matches, int num_matches,
109 	       struct pci_conf *match_buf)
110 {
111 	int i;
112 
113 	if ((matches == NULL) || (match_buf == NULL) || (num_matches <= 0))
114 		return(1);
115 
116 	for (i = 0; i < num_matches; i++) {
117 		/*
118 		 * I'm not sure why someone would do this...but...
119 		 */
120 		if (matches[i].flags == PCI_GETCONF_NO_MATCH)
121 			continue;
122 
123 		/*
124 		 * Look at each of the match flags.  If it's set, do the
125 		 * comparison.  If the comparison fails, we don't have a
126 		 * match, go on to the next item if there is one.
127 		 */
128 		if (((matches[i].flags & PCI_GETCONF_MATCH_BUS) != 0)
129 		 && (match_buf->pc_sel.pc_bus != matches[i].pc_sel.pc_bus))
130 			continue;
131 
132 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEV) != 0)
133 		 && (match_buf->pc_sel.pc_dev != matches[i].pc_sel.pc_dev))
134 			continue;
135 
136 		if (((matches[i].flags & PCI_GETCONF_MATCH_FUNC) != 0)
137 		 && (match_buf->pc_sel.pc_func != matches[i].pc_sel.pc_func))
138 			continue;
139 
140 		if (((matches[i].flags & PCI_GETCONF_MATCH_VENDOR) != 0)
141 		 && (match_buf->pc_vendor != matches[i].pc_vendor))
142 			continue;
143 
144 		if (((matches[i].flags & PCI_GETCONF_MATCH_DEVICE) != 0)
145 		 && (match_buf->pc_device != matches[i].pc_device))
146 			continue;
147 
148 		if (((matches[i].flags & PCI_GETCONF_MATCH_CLASS) != 0)
149 		 && (match_buf->pc_class != matches[i].pc_class))
150 			continue;
151 
152 		if (((matches[i].flags & PCI_GETCONF_MATCH_UNIT) != 0)
153 		 && (match_buf->pd_unit != matches[i].pd_unit))
154 			continue;
155 
156 		if (((matches[i].flags & PCI_GETCONF_MATCH_NAME) != 0)
157 		 && (strncmp(matches[i].pd_name, match_buf->pd_name,
158 			     sizeof(match_buf->pd_name)) != 0))
159 			continue;
160 
161 		return(0);
162 	}
163 
164 	return(1);
165 }
166 
167 static int
168 pci_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td)
169 {
170 	device_t pcidev;
171 	struct pci_io *io;
172 	const char *name;
173 	int error;
174 
175 	if (!(flag & FWRITE) && cmd != PCIOCGETCONF)
176 		return EPERM;
177 
178 	switch(cmd) {
179 	case PCIOCGETCONF:
180 		{
181 		struct pci_devinfo *dinfo;
182 		struct pci_conf_io *cio;
183 		struct devlist *devlist_head;
184 		struct pci_match_conf *pattern_buf;
185 		int num_patterns;
186 		size_t iolen;
187 		int ionum, i;
188 
189 		cio = (struct pci_conf_io *)data;
190 
191 		num_patterns = 0;
192 		dinfo = NULL;
193 
194 		/*
195 		 * If the user specified an offset into the device list,
196 		 * but the list has changed since they last called this
197 		 * ioctl, tell them that the list has changed.  They will
198 		 * have to get the list from the beginning.
199 		 */
200 		if ((cio->offset != 0)
201 		 && (cio->generation != pci_generation)){
202 			cio->num_matches = 0;
203 			cio->status = PCI_GETCONF_LIST_CHANGED;
204 			error = 0;
205 			break;
206 		}
207 
208 		/*
209 		 * Check to see whether the user has asked for an offset
210 		 * past the end of our list.
211 		 */
212 		if (cio->offset >= pci_numdevs) {
213 			cio->num_matches = 0;
214 			cio->status = PCI_GETCONF_LAST_DEVICE;
215 			error = 0;
216 			break;
217 		}
218 
219 		/* get the head of the device queue */
220 		devlist_head = &pci_devq;
221 
222 		/*
223 		 * Determine how much room we have for pci_conf structures.
224 		 * Round the user's buffer size down to the nearest
225 		 * multiple of sizeof(struct pci_conf) in case the user
226 		 * didn't specify a multiple of that size.
227 		 */
228 		iolen = min(cio->match_buf_len -
229 			    (cio->match_buf_len % sizeof(struct pci_conf)),
230 			    pci_numdevs * sizeof(struct pci_conf));
231 
232 		/*
233 		 * Since we know that iolen is a multiple of the size of
234 		 * the pciconf union, it's okay to do this.
235 		 */
236 		ionum = iolen / sizeof(struct pci_conf);
237 
238 		/*
239 		 * If this test is true, the user wants the pci_conf
240 		 * structures returned to match the supplied entries.
241 		 */
242 		if ((cio->num_patterns > 0) && (cio->num_patterns < pci_numdevs)
243 		 && (cio->pat_buf_len > 0)) {
244 			/*
245 			 * pat_buf_len needs to be:
246 			 * num_patterns * sizeof(struct pci_match_conf)
247 			 * While it is certainly possible the user just
248 			 * allocated a large buffer, but set the number of
249 			 * matches correctly, it is far more likely that
250 			 * their kernel doesn't match the userland utility
251 			 * they're using.  It's also possible that the user
252 			 * forgot to initialize some variables.  Yes, this
253 			 * may be overly picky, but I hazard to guess that
254 			 * it's far more likely to just catch folks that
255 			 * updated their kernel but not their userland.
256 			 */
257 			if ((cio->num_patterns *
258 			    sizeof(struct pci_match_conf)) != cio->pat_buf_len){
259 				/* The user made a mistake, return an error*/
260 				cio->status = PCI_GETCONF_ERROR;
261 				cio->num_matches = 0;
262 				error = EINVAL;
263 				break;
264 			}
265 
266 			/*
267 			 * Allocate a buffer to hold the patterns.
268 			 */
269 			pattern_buf = malloc(cio->pat_buf_len, M_TEMP,
270 					     M_WAITOK);
271 			error = copyin(cio->patterns, pattern_buf,
272 				       cio->pat_buf_len);
273 			if (error != 0) {
274 				error = EINVAL;
275 				goto getconfexit;
276 			}
277 			num_patterns = cio->num_patterns;
278 
279 		} else if ((cio->num_patterns > 0)
280 			|| (cio->pat_buf_len > 0)) {
281 			/*
282 			 * The user made a mistake, spit out an error.
283 			 */
284 			cio->status = PCI_GETCONF_ERROR;
285 			cio->num_matches = 0;
286 			error = EINVAL;
287 			break;
288 		} else
289 			pattern_buf = NULL;
290 
291 		/*
292 		 * Go through the list of devices and copy out the devices
293 		 * that match the user's criteria.
294 		 */
295 		for (cio->num_matches = 0, error = 0, i = 0,
296 		     dinfo = STAILQ_FIRST(devlist_head);
297 		     (dinfo != NULL) && (cio->num_matches < ionum)
298 		     && (error == 0) && (i < pci_numdevs) && (dinfo != NULL);
299 		     dinfo = STAILQ_NEXT(dinfo, pci_links), i++) {
300 
301 			if (i < cio->offset)
302 				continue;
303 
304 			/* Populate pd_name and pd_unit */
305 			name = NULL;
306 			if (dinfo->cfg.dev && dinfo->conf.pd_name[0] == '\0')
307 				name = device_get_name(dinfo->cfg.dev);
308 			if (name) {
309 				strncpy(dinfo->conf.pd_name, name,
310 					sizeof(dinfo->conf.pd_name));
311 				dinfo->conf.pd_name[PCI_MAXNAMELEN] = 0;
312 				dinfo->conf.pd_unit =
313 					device_get_unit(dinfo->cfg.dev);
314 			}
315 
316 			if ((pattern_buf == NULL) ||
317 			    (pci_conf_match(pattern_buf, num_patterns,
318 					    &dinfo->conf) == 0)) {
319 
320 				/*
321 				 * If we've filled up the user's buffer,
322 				 * break out at this point.  Since we've
323 				 * got a match here, we'll pick right back
324 				 * up at the matching entry.  We can also
325 				 * tell the user that there are more matches
326 				 * left.
327 				 */
328 				if (cio->num_matches >= ionum)
329 					break;
330 
331 				/* only if can copy it out do we count it */
332 				if (!(error = copyout(&dinfo->conf,
333 				    &cio->matches[cio->num_matches],
334 				    sizeof(struct pci_conf)))) {
335 					cio->num_matches++;
336 				}
337 			}
338 		}
339 
340 		/*
341 		 * Set the pointer into the list, so if the user is getting
342 		 * n records at a time, where n < pci_numdevs,
343 		 */
344 		cio->offset = i;
345 
346 		/*
347 		 * Set the generation, the user will need this if they make
348 		 * another ioctl call with offset != 0.
349 		 */
350 		cio->generation = pci_generation;
351 
352 		/*
353 		 * If this is the last device, inform the user so he won't
354 		 * bother asking for more devices.  If dinfo isn't NULL, we
355 		 * know that there are more matches in the list because of
356 		 * the way the traversal is done.
357 		 */
358 		if (dinfo == NULL)
359 			cio->status = PCI_GETCONF_LAST_DEVICE;
360 		else
361 			cio->status = PCI_GETCONF_MORE_DEVS;
362 
363 getconfexit:
364 		if (pattern_buf != NULL)
365 			free(pattern_buf, M_TEMP);
366 
367 		break;
368 		}
369 
370 	case PCIOCREAD:
371 	case PCIOCWRITE:
372 		io = (struct pci_io *)data;
373 		switch(io->pi_width) {
374 		case 4:
375 		case 2:
376 		case 1:
377 			/* make sure register is in bounds and aligned */
378 			if (cmd == PCIOCREAD || cmd == PCIOCWRITE)
379 				if (io->pi_reg < 0 ||
380 				    io->pi_reg + io->pi_width > PCI_REGMAX ||
381 				    io->pi_reg & (io->pi_width - 1))
382 					error = EINVAL;
383 			/*
384 			 * Assume that the user-level bus number is
385 			 * in fact the physical PCI bus number.
386 			 * Look up the grandparent, i.e. the bridge device,
387 			 * so that we can issue configuration space cycles.
388 			 */
389 			pcidev = pci_find_bsf(io->pi_sel.pc_bus,
390 			    io->pi_sel.pc_dev, io->pi_sel.pc_func);
391 			if (pcidev) {
392 				device_t busdev, brdev;
393 
394 				busdev = device_get_parent(pcidev);
395 				brdev = device_get_parent(busdev);
396 
397 				if (cmd == PCIOCWRITE)
398 					PCIB_WRITE_CONFIG(brdev,
399 							  io->pi_sel.pc_bus,
400 							  io->pi_sel.pc_dev,
401 							  io->pi_sel.pc_func,
402 							  io->pi_reg,
403 							  io->pi_data,
404 							  io->pi_width);
405 				else
406 					io->pi_data =
407 						PCIB_READ_CONFIG(brdev,
408 							  io->pi_sel.pc_bus,
409 							  io->pi_sel.pc_dev,
410 							  io->pi_sel.pc_func,
411 							  io->pi_reg,
412 							  io->pi_width);
413 				error = 0;
414 			} else {
415 #ifdef COMPAT_FREEBSD4
416 				if (cmd == PCIOCREAD) {
417 					io->pi_data = -1;
418 					error = 0;
419 				} else
420 #endif
421 					error = ENODEV;
422 			}
423 			break;
424 		default:
425 			error = EINVAL;
426 			break;
427 		}
428 		break;
429 
430 	default:
431 		error = ENOTTY;
432 		break;
433 	}
434 
435 	return (error);
436 }
437