xref: /freebsd/sys/dev/altera/avgen/altera_avgen.c (revision 3078531de10dcae44b253a35125c949ff4235284)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2012-2013, 2016 Robert N. M. Watson
5  * All rights reserved.
6  *
7  * This software was developed by SRI International and the University of
8  * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
9  * ("CTSRD"), as part of the DARPA CRASH research programme.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/bio.h>
38 #include <sys/bus.h>
39 #include <sys/condvar.h>
40 #include <sys/conf.h>
41 #include <sys/kernel.h>
42 #include <sys/lock.h>
43 #include <sys/malloc.h>
44 #include <sys/module.h>
45 #include <sys/mutex.h>
46 #include <sys/rman.h>
47 #include <sys/stat.h>
48 #include <sys/systm.h>
49 #include <sys/uio.h>
50 
51 #include <geom/geom_disk.h>
52 
53 #include <machine/bus.h>
54 #include <machine/resource.h>
55 
56 #include <vm/vm.h>
57 
58 #include <dev/altera/avgen/altera_avgen.h>
59 
60 /*
61  * Generic device driver for allowing read(), write(), and mmap() on
62  * memory-mapped, Avalon-attached devices.  There is no actual dependence on
63  * Avalon, so conceivably this should just be soc_dev or similar, since many
64  * system-on-chip bus environments would work fine with the same code.
65  */
66 
67 static d_mmap_t altera_avgen_mmap;
68 static d_read_t altera_avgen_read;
69 static d_write_t altera_avgen_write;
70 
71 #define	ALTERA_AVGEN_DEVNAME		"altera_avgen"
72 #define	ALTERA_AVGEN_DEVNAME_FMT	(ALTERA_AVGEN_DEVNAME "%d")
73 
74 static struct cdevsw avg_cdevsw = {
75 	.d_version =	D_VERSION,
76 	.d_mmap =	altera_avgen_mmap,
77 	.d_read =	altera_avgen_read,
78 	.d_write =	altera_avgen_write,
79 	.d_name =	ALTERA_AVGEN_DEVNAME,
80 };
81 
82 #define	ALTERA_AVGEN_SECTORSIZE	512	/* Not configurable at this time. */
83 
84 static int
85 altera_avgen_read(struct cdev *dev, struct uio *uio, int flag)
86 {
87 	struct altera_avgen_softc *sc;
88 	u_long offset, size;
89 #ifdef NOTYET
90 	uint64_t v8;
91 #endif
92 	uint32_t v4;
93 	uint16_t v2;
94 	uint8_t v1;
95 	u_int width;
96 	int error;
97 
98 	sc = dev->si_drv1;
99 	if ((sc->avg_flags & ALTERA_AVALON_FLAG_READ) == 0)
100 		return (EACCES);
101 	width = sc->avg_width;
102 	if (uio->uio_offset < 0 || uio->uio_offset % width != 0 ||
103 	    uio->uio_resid % width != 0)
104 		return (ENODEV);
105 	size = rman_get_size(sc->avg_res);
106 	if ((uio->uio_offset + uio->uio_resid < 0) ||
107 	    (uio->uio_offset + uio->uio_resid > size))
108 		return (ENODEV);
109 	while (uio->uio_resid > 0) {
110 		offset = uio->uio_offset;
111 		if (offset + width > size)
112 			return (ENODEV);
113 		switch (width) {
114 		case 1:
115 			v1 = bus_read_1(sc->avg_res, offset);
116 			error = uiomove(&v1, sizeof(v1), uio);
117 			break;
118 
119 		case 2:
120 			v2 = bus_read_2(sc->avg_res, offset);
121 			error = uiomove(&v2, sizeof(v2), uio);
122 			break;
123 
124 		case 4:
125 			v4 = bus_read_4(sc->avg_res, offset);
126 			error = uiomove(&v4, sizeof(v4), uio);
127 			break;
128 
129 #ifdef NOTYET
130 		case 8:
131 			v8 = bus_read_8(sc->avg_res, offset);
132 			error = uiomove(&v8, sizeof(v8), uio);
133 			break;
134 
135 #endif
136 
137 		default:
138 			panic("%s: unexpected widthment %u", __func__, width);
139 		}
140 		if (error)
141 			return (error);
142 	}
143 	return (0);
144 }
145 
146 static int
147 altera_avgen_write(struct cdev *dev, struct uio *uio, int flag)
148 {
149 	struct altera_avgen_softc *sc;
150 	u_long offset, size;
151 #ifdef NOTYET
152 	uint64_t v8;
153 #endif
154 	uint32_t v4;
155 	uint16_t v2;
156 	uint8_t v1;
157 	u_int width;
158 	int error;
159 
160 	sc = dev->si_drv1;
161 	if ((sc->avg_flags & ALTERA_AVALON_FLAG_WRITE) == 0)
162 		return (EACCES);
163 	width = sc->avg_width;
164 	if (uio->uio_offset < 0 || uio->uio_offset % width != 0 ||
165 	    uio->uio_resid % width != 0)
166 		return (ENODEV);
167 	size = rman_get_size(sc->avg_res);
168 	while (uio->uio_resid > 0) {
169 		offset = uio->uio_offset;
170 		if (offset + width > size)
171 			return (ENODEV);
172 		switch (width) {
173 		case 1:
174 			error = uiomove(&v1, sizeof(v1), uio);
175 			if (error)
176 				return (error);
177 			bus_write_1(sc->avg_res, offset, v1);
178 			break;
179 
180 		case 2:
181 			error = uiomove(&v2, sizeof(v2), uio);
182 			if (error)
183 				return (error);
184 			bus_write_2(sc->avg_res, offset, v2);
185 			break;
186 
187 		case 4:
188 			error = uiomove(&v4, sizeof(v4), uio);
189 			if (error)
190 				return (error);
191 			bus_write_4(sc->avg_res, offset, v4);
192 			break;
193 
194 #ifdef NOTYET
195 		case 8:
196 			error = uiomove(&v8, sizeof(v8), uio);
197 			if (error)
198 				return (error);
199 			bus_write_8(sc->avg_res, offset, v8);
200 			break;
201 #endif
202 
203 		default:
204 			panic("%s: unexpected width %u", __func__, width);
205 		}
206 	}
207 	return (0);
208 }
209 
210 static int
211 altera_avgen_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
212     int nprot, vm_memattr_t *memattr)
213 {
214 	struct altera_avgen_softc *sc;
215 
216 	sc = dev->si_drv1;
217 	if (nprot & VM_PROT_READ) {
218 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_READ) == 0)
219 			return (EACCES);
220 	}
221 	if (nprot & VM_PROT_WRITE) {
222 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_WRITE) == 0)
223 			return (EACCES);
224 	}
225 	if (nprot & VM_PROT_EXECUTE) {
226 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_EXEC) == 0)
227 			return (EACCES);
228 	}
229 	if (trunc_page(offset) == offset &&
230 	    offset + PAGE_SIZE > offset &&
231 	    rman_get_size(sc->avg_res) >= offset + PAGE_SIZE) {
232 		*paddr = rman_get_start(sc->avg_res) + offset;
233 		*memattr = VM_MEMATTR_UNCACHEABLE;
234 	} else
235 		return (ENODEV);
236 	return (0);
237 }
238 
239 /*
240  * NB: We serialise block reads and writes in case the OS is generating
241  * concurrent I/O against the same block, in which case we want one I/O (or
242  * another) to win.  This is not sufficient to provide atomicity for the
243  * sector in the presence of a fail stop -- however, we're just writing this
244  * to non-persistent DRAM .. right?
245  */
246 static void
247 altera_avgen_disk_strategy(struct bio *bp)
248 {
249 	struct altera_avgen_softc *sc;
250 	void *data;
251 	long bcount;
252 	daddr_t pblkno;
253 	int error;
254 
255 	sc = bp->bio_disk->d_drv1;
256 	data = bp->bio_data;
257 	bcount = bp->bio_bcount;
258 	pblkno = bp->bio_pblkno;
259 	error = 0;
260 
261 	/*
262 	 * Serialize block reads / writes.
263 	 */
264 	mtx_lock(&sc->avg_disk_mtx);
265 	switch (bp->bio_cmd) {
266 	case BIO_READ:
267 		if (!(sc->avg_flags & ALTERA_AVALON_FLAG_GEOM_READ)) {
268 			error = EROFS;
269 			break;
270 		}
271 		switch (sc->avg_width) {
272 		case 1:
273 			bus_read_region_1(sc->avg_res,
274 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
275 			    (uint8_t *)data, bcount);
276 			break;
277 
278 		case 2:
279 			bus_read_region_2(sc->avg_res,
280 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
281 			    (uint16_t *)data, bcount / 2);
282 			break;
283 
284 		case 4:
285 			bus_read_region_4(sc->avg_res,
286 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
287 			    (uint32_t *)data, bcount / 4);
288 			break;
289 
290 		default:
291 			panic("%s: unexpected width %u", __func__,
292 			    sc->avg_width);
293 		}
294 		break;
295 
296 	case BIO_WRITE:
297 		if (!(sc->avg_flags & ALTERA_AVALON_FLAG_GEOM_WRITE)) {
298 			biofinish(bp, NULL, EROFS);
299 			break;
300 		}
301 		switch (sc->avg_width) {
302 		case 1:
303 			bus_write_region_1(sc->avg_res,
304 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
305 			    (uint8_t *)data, bcount);
306 			break;
307 
308 		case 2:
309 			bus_write_region_2(sc->avg_res,
310 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
311 			    (uint16_t *)data, bcount / 2);
312 			break;
313 
314 		case 4:
315 			bus_write_region_4(sc->avg_res,
316 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
317 			    (uint32_t *)data, bcount / 4);
318 			break;
319 
320 		default:
321 			panic("%s: unexpected width %u", __func__,
322 			    sc->avg_width);
323 		}
324 		break;
325 
326 	default:
327 		error = EOPNOTSUPP;
328 		break;
329 	}
330 	mtx_unlock(&sc->avg_disk_mtx);
331 	biofinish(bp, NULL, error);
332 }
333 
334 static int
335 altera_avgen_process_options(struct altera_avgen_softc *sc,
336     const char *str_fileio, const char *str_geomio, const char *str_mmapio,
337     const char *str_devname, int devunit)
338 {
339 	const char *cp;
340 	device_t dev = sc->avg_dev;
341 
342 	/*
343 	 * Check for valid combinations of options.
344 	 */
345 	if (str_fileio == NULL && str_geomio == NULL && str_mmapio == NULL) {
346 		device_printf(dev,
347 		    "at least one of %s, %s, or %s must be specified\n",
348 		    ALTERA_AVALON_STR_FILEIO, ALTERA_AVALON_STR_GEOMIO,
349 		    ALTERA_AVALON_STR_MMAPIO);
350 		return (ENXIO);
351 	}
352 
353 	/*
354 	 * Validity check: a device can either be a GEOM device (in which case
355 	 * we use GEOM to register the device node), or a special device --
356 	 * but not both as that causes a collision in /dev.
357 	 */
358 	if (str_geomio != NULL && (str_fileio != NULL || str_mmapio != NULL)) {
359 		device_printf(dev,
360 		    "at most one of %s and (%s or %s) may be specified\n",
361 		    ALTERA_AVALON_STR_GEOMIO, ALTERA_AVALON_STR_FILEIO,
362 		    ALTERA_AVALON_STR_MMAPIO);
363 		return (ENXIO);
364 	}
365 
366 	/*
367 	 * Ensure that a unit is specified if a name is also specified.
368 	 */
369 	if (str_devname == NULL && devunit != -1) {
370 		device_printf(dev, "%s requires %s be specified\n",
371 		    ALTERA_AVALON_STR_DEVUNIT, ALTERA_AVALON_STR_DEVNAME);
372 		return (ENXIO);
373 	}
374 
375 	/*
376 	 * Extract, digest, and save values.
377 	 */
378 	switch (sc->avg_width) {
379 	case 1:
380 	case 2:
381 	case 4:
382 #ifdef NOTYET
383 	case 8:
384 #endif
385 		break;
386 
387 	default:
388 		device_printf(dev, "%s unsupported value %u\n",
389 		    ALTERA_AVALON_STR_WIDTH, sc->avg_width);
390 		return (ENXIO);
391 	}
392 	sc->avg_flags = 0;
393 	if (str_fileio != NULL) {
394 		for (cp = str_fileio; *cp != '\0'; cp++) {
395 			switch (*cp) {
396 			case ALTERA_AVALON_CHAR_READ:
397 				sc->avg_flags |= ALTERA_AVALON_FLAG_READ;
398 				break;
399 
400 			case ALTERA_AVALON_CHAR_WRITE:
401 				sc->avg_flags |= ALTERA_AVALON_FLAG_WRITE;
402 				break;
403 
404 			default:
405 				device_printf(dev,
406 				    "invalid %s character %c\n",
407 				    ALTERA_AVALON_STR_FILEIO, *cp);
408 				return (ENXIO);
409 			}
410 		}
411 	}
412 	if (str_geomio != NULL) {
413 		for (cp = str_geomio; *cp != '\0'; cp++){
414 			switch (*cp) {
415 			case ALTERA_AVALON_CHAR_READ:
416 				sc->avg_flags |= ALTERA_AVALON_FLAG_GEOM_READ;
417 				break;
418 
419 			case ALTERA_AVALON_CHAR_WRITE:
420 				sc->avg_flags |= ALTERA_AVALON_FLAG_GEOM_WRITE;
421 				break;
422 
423 			default:
424 				device_printf(dev,
425 				    "invalid %s character %c\n",
426 				    ALTERA_AVALON_STR_GEOMIO, *cp);
427 				return (ENXIO);
428 			}
429 		}
430 	}
431 	if (str_mmapio != NULL) {
432 		for (cp = str_mmapio; *cp != '\0'; cp++) {
433 			switch (*cp) {
434 			case ALTERA_AVALON_CHAR_READ:
435 				sc->avg_flags |= ALTERA_AVALON_FLAG_MMAP_READ;
436 				break;
437 
438 			case ALTERA_AVALON_CHAR_WRITE:
439 				sc->avg_flags |=
440 				    ALTERA_AVALON_FLAG_MMAP_WRITE;
441 				break;
442 
443 			case ALTERA_AVALON_CHAR_EXEC:
444 				sc->avg_flags |= ALTERA_AVALON_FLAG_MMAP_EXEC;
445 				break;
446 
447 			default:
448 				device_printf(dev,
449 				    "invalid %s character %c\n",
450 				    ALTERA_AVALON_STR_MMAPIO, *cp);
451 				return (ENXIO);
452 			}
453 		}
454 	}
455 	return (0);
456 }
457 
458 int
459 altera_avgen_attach(struct altera_avgen_softc *sc, const char *str_fileio,
460     const char *str_geomio, const char *str_mmapio, const char *str_devname,
461     int devunit)
462 {
463 	device_t dev = sc->avg_dev;
464 	int error;
465 
466 	error = altera_avgen_process_options(sc, str_fileio, str_geomio,
467 	    str_mmapio, str_devname, devunit);
468 	if (error)
469 		return (error);
470 
471 	if (rman_get_size(sc->avg_res) >= PAGE_SIZE || str_mmapio != NULL) {
472 		if (rman_get_size(sc->avg_res) % PAGE_SIZE != 0) {
473 			device_printf(dev,
474 			    "memory region not even multiple of page size\n");
475 			return (ENXIO);
476 		}
477 		if (rman_get_start(sc->avg_res) % PAGE_SIZE != 0) {
478 			device_printf(dev, "memory region not page-aligned\n");
479 			return (ENXIO);
480 		}
481 	}
482 
483 	/*
484 	 * If a GEOM permission is requested, then create the device via GEOM.
485 	 * Otherwise, create a special device.  We checked during options
486 	 * processing that both weren't requested a once.
487 	 */
488 	if (str_devname != NULL) {
489 		sc->avg_name = strdup(str_devname, M_TEMP);
490 		devunit = sc->avg_unit;
491 	} else
492 		sc->avg_name = strdup(ALTERA_AVGEN_DEVNAME, M_TEMP);
493 	if (sc->avg_flags & (ALTERA_AVALON_FLAG_GEOM_READ |
494 	    ALTERA_AVALON_FLAG_GEOM_WRITE)) {
495 		mtx_init(&sc->avg_disk_mtx, "altera_avgen_disk", NULL,
496 		    MTX_DEF);
497 		sc->avg_disk = disk_alloc();
498 		sc->avg_disk->d_drv1 = sc;
499 		sc->avg_disk->d_strategy = altera_avgen_disk_strategy;
500 		if (devunit == -1)
501 			devunit = 0;
502 		sc->avg_disk->d_name = sc->avg_name;
503 		sc->avg_disk->d_unit = devunit;
504 
505 		/*
506 		 * NB: As avg_res is a multiple of PAGE_SIZE, it is also a
507 		 * multiple of ALTERA_AVGEN_SECTORSIZE.
508 		 */
509 		sc->avg_disk->d_sectorsize = ALTERA_AVGEN_SECTORSIZE;
510 		sc->avg_disk->d_mediasize = rman_get_size(sc->avg_res);
511 		sc->avg_disk->d_maxsize = ALTERA_AVGEN_SECTORSIZE;
512 		disk_create(sc->avg_disk, DISK_VERSION);
513 	} else {
514 		/* Device node allocation. */
515 		if (str_devname == NULL) {
516 			str_devname = ALTERA_AVGEN_DEVNAME_FMT;
517 			devunit = sc->avg_unit;
518 		}
519 		if (devunit != -1)
520 			sc->avg_cdev = make_dev(&avg_cdevsw, sc->avg_unit,
521 			    UID_ROOT, GID_WHEEL, S_IRUSR | S_IWUSR, "%s%d",
522 			    str_devname, devunit);
523 		else
524 			sc->avg_cdev = make_dev(&avg_cdevsw, sc->avg_unit,
525 			    UID_ROOT, GID_WHEEL, S_IRUSR | S_IWUSR,
526 			    "%s", str_devname);
527 		if (sc->avg_cdev == NULL) {
528 			device_printf(sc->avg_dev, "%s: make_dev failed\n",
529 			    __func__);
530 			return (ENXIO);
531 		}
532 
533 		/* XXXRW: Slight race between make_dev(9) and here. */
534 		sc->avg_cdev->si_drv1 = sc;
535 	}
536 	return (0);
537 }
538 
539 void
540 altera_avgen_detach(struct altera_avgen_softc *sc)
541 {
542 
543 	KASSERT((sc->avg_disk != NULL) || (sc->avg_cdev != NULL),
544 	    ("%s: neither GEOM nor special device", __func__));
545 
546 	if (sc->avg_disk != NULL) {
547 		disk_gone(sc->avg_disk);
548 		disk_destroy(sc->avg_disk);
549 		free(sc->avg_name, M_TEMP);
550 		mtx_destroy(&sc->avg_disk_mtx);
551 	} else {
552 		destroy_dev(sc->avg_cdev);
553 	}
554 }
555