xref: /freebsd/sys/dev/altera/avgen/altera_avgen.c (revision 580744621f33383027108364dcadad718df46ffe)
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 devclass_t altera_avgen_devclass;
68 
69 static d_mmap_t altera_avgen_mmap;
70 static d_read_t altera_avgen_read;
71 static d_write_t altera_avgen_write;
72 
73 #define	ALTERA_AVGEN_DEVNAME		"altera_avgen"
74 #define	ALTERA_AVGEN_DEVNAME_FMT	(ALTERA_AVGEN_DEVNAME "%d")
75 
76 static struct cdevsw avg_cdevsw = {
77 	.d_version =	D_VERSION,
78 	.d_mmap =	altera_avgen_mmap,
79 	.d_read =	altera_avgen_read,
80 	.d_write =	altera_avgen_write,
81 	.d_name =	ALTERA_AVGEN_DEVNAME,
82 };
83 
84 #define	ALTERA_AVGEN_SECTORSIZE	512	/* Not configurable at this time. */
85 
86 static int
87 altera_avgen_read(struct cdev *dev, struct uio *uio, int flag)
88 {
89 	struct altera_avgen_softc *sc;
90 	u_long offset, size;
91 #ifdef NOTYET
92 	uint64_t v8;
93 #endif
94 	uint32_t v4;
95 	uint16_t v2;
96 	uint8_t v1;
97 	u_int width;
98 	int error;
99 
100 	sc = dev->si_drv1;
101 	if ((sc->avg_flags & ALTERA_AVALON_FLAG_READ) == 0)
102 		return (EACCES);
103 	width = sc->avg_width;
104 	if (uio->uio_offset < 0 || uio->uio_offset % width != 0 ||
105 	    uio->uio_resid % width != 0)
106 		return (ENODEV);
107 	size = rman_get_size(sc->avg_res);
108 	if ((uio->uio_offset + uio->uio_resid < 0) ||
109 	    (uio->uio_offset + uio->uio_resid > size))
110 		return (ENODEV);
111 	while (uio->uio_resid > 0) {
112 		offset = uio->uio_offset;
113 		if (offset + width > size)
114 			return (ENODEV);
115 		switch (width) {
116 		case 1:
117 			v1 = bus_read_1(sc->avg_res, offset);
118 			error = uiomove(&v1, sizeof(v1), uio);
119 			break;
120 
121 		case 2:
122 			v2 = bus_read_2(sc->avg_res, offset);
123 			error = uiomove(&v2, sizeof(v2), uio);
124 			break;
125 
126 		case 4:
127 			v4 = bus_read_4(sc->avg_res, offset);
128 			error = uiomove(&v4, sizeof(v4), uio);
129 			break;
130 
131 #ifdef NOTYET
132 		case 8:
133 			v8 = bus_read_8(sc->avg_res, offset);
134 			error = uiomove(&v8, sizeof(v8), uio);
135 			break;
136 
137 #endif
138 
139 		default:
140 			panic("%s: unexpected widthment %u", __func__, width);
141 		}
142 		if (error)
143 			return (error);
144 	}
145 	return (0);
146 }
147 
148 static int
149 altera_avgen_write(struct cdev *dev, struct uio *uio, int flag)
150 {
151 	struct altera_avgen_softc *sc;
152 	u_long offset, size;
153 #ifdef NOTYET
154 	uint64_t v8;
155 #endif
156 	uint32_t v4;
157 	uint16_t v2;
158 	uint8_t v1;
159 	u_int width;
160 	int error;
161 
162 	sc = dev->si_drv1;
163 	if ((sc->avg_flags & ALTERA_AVALON_FLAG_WRITE) == 0)
164 		return (EACCES);
165 	width = sc->avg_width;
166 	if (uio->uio_offset < 0 || uio->uio_offset % width != 0 ||
167 	    uio->uio_resid % width != 0)
168 		return (ENODEV);
169 	size = rman_get_size(sc->avg_res);
170 	while (uio->uio_resid > 0) {
171 		offset = uio->uio_offset;
172 		if (offset + width > size)
173 			return (ENODEV);
174 		switch (width) {
175 		case 1:
176 			error = uiomove(&v1, sizeof(v1), uio);
177 			if (error)
178 				return (error);
179 			bus_write_1(sc->avg_res, offset, v1);
180 			break;
181 
182 		case 2:
183 			error = uiomove(&v2, sizeof(v2), uio);
184 			if (error)
185 				return (error);
186 			bus_write_2(sc->avg_res, offset, v2);
187 			break;
188 
189 		case 4:
190 			error = uiomove(&v4, sizeof(v4), uio);
191 			if (error)
192 				return (error);
193 			bus_write_4(sc->avg_res, offset, v4);
194 			break;
195 
196 #ifdef NOTYET
197 		case 8:
198 			error = uiomove(&v8, sizeof(v8), uio);
199 			if (error)
200 				return (error);
201 			bus_write_8(sc->avg_res, offset, v8);
202 			break;
203 #endif
204 
205 		default:
206 			panic("%s: unexpected width %u", __func__, width);
207 		}
208 	}
209 	return (0);
210 }
211 
212 static int
213 altera_avgen_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
214     int nprot, vm_memattr_t *memattr)
215 {
216 	struct altera_avgen_softc *sc;
217 
218 	sc = dev->si_drv1;
219 	if (nprot & VM_PROT_READ) {
220 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_READ) == 0)
221 			return (EACCES);
222 	}
223 	if (nprot & VM_PROT_WRITE) {
224 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_WRITE) == 0)
225 			return (EACCES);
226 	}
227 	if (nprot & VM_PROT_EXECUTE) {
228 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_EXEC) == 0)
229 			return (EACCES);
230 	}
231 	if (trunc_page(offset) == offset &&
232 	    offset + PAGE_SIZE > offset &&
233 	    rman_get_size(sc->avg_res) >= offset + PAGE_SIZE) {
234 		*paddr = rman_get_start(sc->avg_res) + offset;
235 		*memattr = VM_MEMATTR_UNCACHEABLE;
236 	} else
237 		return (ENODEV);
238 	return (0);
239 }
240 
241 /*
242  * NB: We serialise block reads and writes in case the OS is generating
243  * concurrent I/O against the same block, in which case we want one I/O (or
244  * another) to win.  This is not sufficient to provide atomicity for the
245  * sector in the presence of a fail stop -- however, we're just writing this
246  * to non-persistent DRAM .. right?
247  */
248 static void
249 altera_avgen_disk_strategy(struct bio *bp)
250 {
251 	struct altera_avgen_softc *sc;
252 	void *data;
253 	long bcount;
254 	daddr_t pblkno;
255 	int error;
256 
257 	sc = bp->bio_disk->d_drv1;
258 	data = bp->bio_data;
259 	bcount = bp->bio_bcount;
260 	pblkno = bp->bio_pblkno;
261 	error = 0;
262 
263 	/*
264 	 * Serialize block reads / writes.
265 	 */
266 	mtx_lock(&sc->avg_disk_mtx);
267 	switch (bp->bio_cmd) {
268 	case BIO_READ:
269 		if (!(sc->avg_flags & ALTERA_AVALON_FLAG_GEOM_READ)) {
270 			error = EROFS;
271 			break;
272 		}
273 		switch (sc->avg_width) {
274 		case 1:
275 			bus_read_region_1(sc->avg_res,
276 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
277 			    (uint8_t *)data, bcount);
278 			break;
279 
280 		case 2:
281 			bus_read_region_2(sc->avg_res,
282 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
283 			    (uint16_t *)data, bcount / 2);
284 			break;
285 
286 		case 4:
287 			bus_read_region_4(sc->avg_res,
288 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
289 			    (uint32_t *)data, bcount / 4);
290 			break;
291 
292 		default:
293 			panic("%s: unexpected width %u", __func__,
294 			    sc->avg_width);
295 		}
296 		break;
297 
298 	case BIO_WRITE:
299 		if (!(sc->avg_flags & ALTERA_AVALON_FLAG_GEOM_WRITE)) {
300 			biofinish(bp, NULL, EROFS);
301 			break;
302 		}
303 		switch (sc->avg_width) {
304 		case 1:
305 			bus_write_region_1(sc->avg_res,
306 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
307 			    (uint8_t *)data, bcount);
308 			break;
309 
310 		case 2:
311 			bus_write_region_2(sc->avg_res,
312 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
313 			    (uint16_t *)data, bcount / 2);
314 			break;
315 
316 		case 4:
317 			bus_write_region_4(sc->avg_res,
318 			    bp->bio_pblkno * ALTERA_AVGEN_SECTORSIZE,
319 			    (uint32_t *)data, bcount / 4);
320 			break;
321 
322 		default:
323 			panic("%s: unexpected width %u", __func__,
324 			    sc->avg_width);
325 		}
326 		break;
327 
328 	default:
329 		error = EOPNOTSUPP;
330 		break;
331 	}
332 	mtx_unlock(&sc->avg_disk_mtx);
333 	biofinish(bp, NULL, error);
334 }
335 
336 static int
337 altera_avgen_process_options(struct altera_avgen_softc *sc,
338     const char *str_fileio, const char *str_geomio, const char *str_mmapio,
339     const char *str_devname, int devunit)
340 {
341 	const char *cp;
342 	device_t dev = sc->avg_dev;
343 
344 	/*
345 	 * Check for valid combinations of options.
346 	 */
347 	if (str_fileio == NULL && str_geomio == NULL && str_mmapio == NULL) {
348 		device_printf(dev,
349 		    "at least one of %s, %s, or %s must be specified\n",
350 		    ALTERA_AVALON_STR_FILEIO, ALTERA_AVALON_STR_GEOMIO,
351 		    ALTERA_AVALON_STR_MMAPIO);
352 		return (ENXIO);
353 	}
354 
355 	/*
356 	 * Validity check: a device can either be a GEOM device (in which case
357 	 * we use GEOM to register the device node), or a special device --
358 	 * but not both as that causes a collision in /dev.
359 	 */
360 	if (str_geomio != NULL && (str_fileio != NULL || str_mmapio != NULL)) {
361 		device_printf(dev,
362 		    "at most one of %s and (%s or %s) may be specified\n",
363 		    ALTERA_AVALON_STR_GEOMIO, ALTERA_AVALON_STR_FILEIO,
364 		    ALTERA_AVALON_STR_MMAPIO);
365 		return (ENXIO);
366 	}
367 
368 	/*
369 	 * Ensure that a unit is specified if a name is also specified.
370 	 */
371 	if (str_devname == NULL && devunit != -1) {
372 		device_printf(dev, "%s requires %s be specified\n",
373 		    ALTERA_AVALON_STR_DEVUNIT, ALTERA_AVALON_STR_DEVNAME);
374 		return (ENXIO);
375 	}
376 
377 	/*
378 	 * Extract, digest, and save values.
379 	 */
380 	switch (sc->avg_width) {
381 	case 1:
382 	case 2:
383 	case 4:
384 #ifdef NOTYET
385 	case 8:
386 #endif
387 		break;
388 
389 	default:
390 		device_printf(dev, "%s unsupported value %u\n",
391 		    ALTERA_AVALON_STR_WIDTH, sc->avg_width);
392 		return (ENXIO);
393 	}
394 	sc->avg_flags = 0;
395 	if (str_fileio != NULL) {
396 		for (cp = str_fileio; *cp != '\0'; cp++) {
397 			switch (*cp) {
398 			case ALTERA_AVALON_CHAR_READ:
399 				sc->avg_flags |= ALTERA_AVALON_FLAG_READ;
400 				break;
401 
402 			case ALTERA_AVALON_CHAR_WRITE:
403 				sc->avg_flags |= ALTERA_AVALON_FLAG_WRITE;
404 				break;
405 
406 			default:
407 				device_printf(dev,
408 				    "invalid %s character %c\n",
409 				    ALTERA_AVALON_STR_FILEIO, *cp);
410 				return (ENXIO);
411 			}
412 		}
413 	}
414 	if (str_geomio != NULL) {
415 		for (cp = str_geomio; *cp != '\0'; cp++){
416 			switch (*cp) {
417 			case ALTERA_AVALON_CHAR_READ:
418 				sc->avg_flags |= ALTERA_AVALON_FLAG_GEOM_READ;
419 				break;
420 
421 			case ALTERA_AVALON_CHAR_WRITE:
422 				sc->avg_flags |= ALTERA_AVALON_FLAG_GEOM_WRITE;
423 				break;
424 
425 			default:
426 				device_printf(dev,
427 				    "invalid %s character %c\n",
428 				    ALTERA_AVALON_STR_GEOMIO, *cp);
429 				return (ENXIO);
430 			}
431 		}
432 	}
433 	if (str_mmapio != NULL) {
434 		for (cp = str_mmapio; *cp != '\0'; cp++) {
435 			switch (*cp) {
436 			case ALTERA_AVALON_CHAR_READ:
437 				sc->avg_flags |= ALTERA_AVALON_FLAG_MMAP_READ;
438 				break;
439 
440 			case ALTERA_AVALON_CHAR_WRITE:
441 				sc->avg_flags |=
442 				    ALTERA_AVALON_FLAG_MMAP_WRITE;
443 				break;
444 
445 			case ALTERA_AVALON_CHAR_EXEC:
446 				sc->avg_flags |= ALTERA_AVALON_FLAG_MMAP_EXEC;
447 				break;
448 
449 			default:
450 				device_printf(dev,
451 				    "invalid %s character %c\n",
452 				    ALTERA_AVALON_STR_MMAPIO, *cp);
453 				return (ENXIO);
454 			}
455 		}
456 	}
457 	return (0);
458 }
459 
460 int
461 altera_avgen_attach(struct altera_avgen_softc *sc, const char *str_fileio,
462     const char *str_geomio, const char *str_mmapio, const char *str_devname,
463     int devunit)
464 {
465 	device_t dev = sc->avg_dev;
466 	int error;
467 
468 	error = altera_avgen_process_options(sc, str_fileio, str_geomio,
469 	    str_mmapio, str_devname, devunit);
470 	if (error)
471 		return (error);
472 
473 	if (rman_get_size(sc->avg_res) >= PAGE_SIZE || str_mmapio != NULL) {
474 		if (rman_get_size(sc->avg_res) % PAGE_SIZE != 0) {
475 			device_printf(dev,
476 			    "memory region not even multiple of page size\n");
477 			return (ENXIO);
478 		}
479 		if (rman_get_start(sc->avg_res) % PAGE_SIZE != 0) {
480 			device_printf(dev, "memory region not page-aligned\n");
481 			return (ENXIO);
482 		}
483 	}
484 
485 	/*
486 	 * If a GEOM permission is requested, then create the device via GEOM.
487 	 * Otherwise, create a special device.  We checked during options
488 	 * processing that both weren't requested a once.
489 	 */
490 	if (str_devname != NULL) {
491 		sc->avg_name = strdup(str_devname, M_TEMP);
492 		devunit = sc->avg_unit;
493 	} else
494 		sc->avg_name = strdup(ALTERA_AVGEN_DEVNAME, M_TEMP);
495 	if (sc->avg_flags & (ALTERA_AVALON_FLAG_GEOM_READ |
496 	    ALTERA_AVALON_FLAG_GEOM_WRITE)) {
497 		mtx_init(&sc->avg_disk_mtx, "altera_avgen_disk", NULL,
498 		    MTX_DEF);
499 		sc->avg_disk = disk_alloc();
500 		sc->avg_disk->d_drv1 = sc;
501 		sc->avg_disk->d_strategy = altera_avgen_disk_strategy;
502 		if (devunit == -1)
503 			devunit = 0;
504 		sc->avg_disk->d_name = sc->avg_name;
505 		sc->avg_disk->d_unit = devunit;
506 
507 		/*
508 		 * NB: As avg_res is a multiple of PAGE_SIZE, it is also a
509 		 * multiple of ALTERA_AVGEN_SECTORSIZE.
510 		 */
511 		sc->avg_disk->d_sectorsize = ALTERA_AVGEN_SECTORSIZE;
512 		sc->avg_disk->d_mediasize = rman_get_size(sc->avg_res);
513 		sc->avg_disk->d_maxsize = ALTERA_AVGEN_SECTORSIZE;
514 		disk_create(sc->avg_disk, DISK_VERSION);
515 	} else {
516 		/* Device node allocation. */
517 		if (str_devname == NULL) {
518 			str_devname = ALTERA_AVGEN_DEVNAME_FMT;
519 			devunit = sc->avg_unit;
520 		}
521 		if (devunit != -1)
522 			sc->avg_cdev = make_dev(&avg_cdevsw, sc->avg_unit,
523 			    UID_ROOT, GID_WHEEL, S_IRUSR | S_IWUSR, "%s%d",
524 			    str_devname, devunit);
525 		else
526 			sc->avg_cdev = make_dev(&avg_cdevsw, sc->avg_unit,
527 			    UID_ROOT, GID_WHEEL, S_IRUSR | S_IWUSR,
528 			    "%s", str_devname);
529 		if (sc->avg_cdev == NULL) {
530 			device_printf(sc->avg_dev, "%s: make_dev failed\n",
531 			    __func__);
532 			return (ENXIO);
533 		}
534 
535 		/* XXXRW: Slight race between make_dev(9) and here. */
536 		sc->avg_cdev->si_drv1 = sc;
537 	}
538 	return (0);
539 }
540 
541 void
542 altera_avgen_detach(struct altera_avgen_softc *sc)
543 {
544 
545 	KASSERT((sc->avg_disk != NULL) || (sc->avg_cdev != NULL),
546 	    ("%s: neither GEOM nor special device", __func__));
547 
548 	if (sc->avg_disk != NULL) {
549 		disk_gone(sc->avg_disk);
550 		disk_destroy(sc->avg_disk);
551 		free(sc->avg_name, M_TEMP);
552 		mtx_destroy(&sc->avg_disk_mtx);
553 	} else {
554 		destroy_dev(sc->avg_cdev);
555 	}
556 }
557