xref: /freebsd/sys/dev/altera/avgen/altera_avgen.c (revision b352b104)
1 /*-
2  * Copyright (c) 2012-2013 Robert N. M. Watson
3  * All rights reserved.
4  *
5  * This software was developed by SRI International and the University of
6  * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
7  * ("CTSRD"), as part of the DARPA CRASH research programme.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/bus.h>
36 #include <sys/condvar.h>
37 #include <sys/conf.h>
38 #include <sys/kernel.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/module.h>
42 #include <sys/mutex.h>
43 #include <sys/rman.h>
44 #include <sys/stat.h>
45 #include <sys/systm.h>
46 #include <sys/uio.h>
47 
48 #include <machine/bus.h>
49 #include <machine/resource.h>
50 
51 #include <vm/vm.h>
52 
53 #include <dev/altera/avgen/altera_avgen.h>
54 
55 /*
56  * Generic device driver for allowing read(), write(), and mmap() on
57  * memory-mapped, Avalon-attached devices.  There is no actual dependence on
58  * Avalon, so conceivably this should just be soc_dev or similar, since many
59  * system-on-chip bus environments would work fine with the same code.
60  */
61 
62 devclass_t altera_avgen_devclass;
63 
64 static d_mmap_t altera_avgen_mmap;
65 static d_read_t altera_avgen_read;
66 static d_write_t altera_avgen_write;
67 
68 static struct cdevsw avg_cdevsw = {
69 	.d_version =	D_VERSION,
70 	.d_mmap =	altera_avgen_mmap,
71 	.d_read =	altera_avgen_read,
72 	.d_write =	altera_avgen_write,
73 	.d_name =	"altera_avgen",
74 };
75 
76 static int
77 altera_avgen_read(struct cdev *dev, struct uio *uio, int flag)
78 {
79 	struct altera_avgen_softc *sc;
80 	u_long offset, size;
81 #ifdef NOTYET
82 	uint64_t v8;
83 #endif
84 	uint32_t v4;
85 	uint16_t v2;
86 	uint8_t v1;
87 	u_int width;
88 	int error;
89 
90 	sc = dev->si_drv1;
91 	if ((sc->avg_flags & ALTERA_AVALON_FLAG_READ) == 0)
92 		return (EACCES);
93 	width = sc->avg_width;
94 	if (uio->uio_offset < 0 || uio->uio_offset % width != 0 ||
95 	    uio->uio_resid % width != 0)
96 		return (ENODEV);
97 	size = rman_get_size(sc->avg_res);
98 	if ((uio->uio_offset + uio->uio_resid < 0) ||
99 	    (uio->uio_offset + uio->uio_resid > size))
100 		return (ENODEV);
101 	while (uio->uio_resid > 0) {
102 		offset = uio->uio_offset;
103 		if (offset + width > size)
104 			return (ENODEV);
105 		switch (width) {
106 		case 1:
107 			v1 = bus_read_1(sc->avg_res, offset);
108 			error = uiomove(&v1, sizeof(v1), uio);
109 			break;
110 
111 		case 2:
112 			v2 = bus_read_2(sc->avg_res, offset);
113 			error = uiomove(&v2, sizeof(v2), uio);
114 			break;
115 
116 		case 4:
117 			v4 = bus_read_4(sc->avg_res, offset);
118 			error = uiomove(&v4, sizeof(v4), uio);
119 			break;
120 
121 #ifdef NOTYET
122 		case 8:
123 			v8 = bus_read_8(sc->avg_res, offset);
124 			error = uiomove(&v8, sizeof(v8), uio);
125 			break;
126 
127 #endif
128 
129 		default:
130 			panic("%s: unexpected widthment %u", __func__, width);
131 		}
132 		if (error)
133 			return (error);
134 	}
135 	return (0);
136 }
137 
138 static int
139 altera_avgen_write(struct cdev *dev, struct uio *uio, int flag)
140 {
141 	struct altera_avgen_softc *sc;
142 	u_long offset, size;
143 #ifdef NOTYET
144 	uint64_t v8;
145 #endif
146 	uint32_t v4;
147 	uint16_t v2;
148 	uint8_t v1;
149 	u_int width;
150 	int error;
151 
152 	sc = dev->si_drv1;
153 	if ((sc->avg_flags & ALTERA_AVALON_FLAG_WRITE) == 0)
154 		return (EACCES);
155 	width = sc->avg_width;
156 	if (uio->uio_offset < 0 || uio->uio_offset % width != 0 ||
157 	    uio->uio_resid % width != 0)
158 		return (ENODEV);
159 	size = rman_get_size(sc->avg_res);
160 	while (uio->uio_resid > 0) {
161 		offset = uio->uio_offset;
162 		if (offset + width > size)
163 			return (ENODEV);
164 		switch (width) {
165 		case 1:
166 			error = uiomove(&v1, sizeof(v1), uio);
167 			if (error)
168 				return (error);
169 			bus_write_1(sc->avg_res, offset, v1);
170 			break;
171 
172 		case 2:
173 			error = uiomove(&v2, sizeof(v2), uio);
174 			if (error)
175 				return (error);
176 			bus_write_2(sc->avg_res, offset, v2);
177 			break;
178 
179 		case 4:
180 			error = uiomove(&v4, sizeof(v4), uio);
181 			if (error)
182 				return (error);
183 			bus_write_4(sc->avg_res, offset, v4);
184 			break;
185 
186 #ifdef NOTYET
187 		case 8:
188 			error = uiomove(&v8, sizeof(v8), uio);
189 			if (error)
190 				return (error);
191 			bus_write_8(sc->avg_res, offset, v8);
192 			break;
193 #endif
194 
195 		default:
196 			panic("%s: unexpected width %u", __func__, width);
197 		}
198 	}
199 	return (0);
200 }
201 
202 static int
203 altera_avgen_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
204     int nprot, vm_memattr_t *memattr)
205 {
206 	struct altera_avgen_softc *sc;
207 
208 	sc = dev->si_drv1;
209 	if (nprot & VM_PROT_READ) {
210 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_READ) == 0)
211 			return (EACCES);
212 	}
213 	if (nprot & VM_PROT_WRITE) {
214 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_WRITE) == 0)
215 			return (EACCES);
216 	}
217 	if (nprot & VM_PROT_EXECUTE) {
218 		if ((sc->avg_flags & ALTERA_AVALON_FLAG_MMAP_EXEC) == 0)
219 			return (EACCES);
220 	}
221 	if (trunc_page(offset) == offset &&
222 	    rman_get_size(sc->avg_res) >= offset + PAGE_SIZE) {
223 		*paddr = rman_get_start(sc->avg_res) + offset;
224 		*memattr = VM_MEMATTR_UNCACHEABLE;
225 	} else
226 		return (ENODEV);
227 	return (0);
228 }
229 
230 
231 static int
232 altera_avgen_process_options(struct altera_avgen_softc *sc,
233     const char *str_fileio, const char *str_mmapio, const char *str_devname,
234     int devunit)
235 {
236 	const char *cp;
237 	device_t dev = sc->avg_dev;
238 
239 	/*
240 	 * Check for valid combinations of options.
241 	 */
242 	if (str_fileio == NULL && str_mmapio == NULL) {
243 		device_printf(dev,
244 		    "at least one of %s or %s must be specified\n",
245 		    ALTERA_AVALON_STR_FILEIO, ALTERA_AVALON_STR_MMAPIO);
246 		return (ENXIO);
247 	}
248 	if (str_devname == NULL && devunit != -1) {
249 		device_printf(dev, "%s requires %s be specified\n",
250 		    ALTERA_AVALON_STR_DEVUNIT, ALTERA_AVALON_STR_DEVNAME);
251 		return (ENXIO);
252 	}
253 
254 	/*
255 	 * Extract, digest, and save values.
256 	 */
257 	switch (sc->avg_width) {
258 	case 1:
259 	case 2:
260 	case 4:
261 #ifdef NOTYET
262 	case 8:
263 #endif
264 		break;
265 
266 	default:
267 		device_printf(dev, "%s unsupported value %u\n",
268 		    ALTERA_AVALON_STR_WIDTH, sc->avg_width);
269 		return (ENXIO);
270 	}
271 	sc->avg_flags = 0;
272 	if (str_fileio != NULL) {
273 		for (cp = str_fileio; *cp != '\0'; cp++) {
274 			switch (*cp) {
275 			case ALTERA_AVALON_CHAR_READ:
276 				sc->avg_flags |= ALTERA_AVALON_FLAG_READ;
277 				break;
278 
279 			case ALTERA_AVALON_CHAR_WRITE:
280 				sc->avg_flags |= ALTERA_AVALON_FLAG_WRITE;
281 				break;
282 
283 			default:
284 				device_printf(dev,
285 				    "invalid %s character %c\n",
286 				    ALTERA_AVALON_STR_FILEIO, *cp);
287 				return (ENXIO);
288 			}
289 		}
290 	}
291 	if (str_mmapio != NULL) {
292 		for (cp = str_mmapio; *cp != '\0'; cp++) {
293 			switch (*cp) {
294 			case ALTERA_AVALON_CHAR_READ:
295 				sc->avg_flags |= ALTERA_AVALON_FLAG_MMAP_READ;
296 				break;
297 
298 			case ALTERA_AVALON_CHAR_WRITE:
299 				sc->avg_flags |=
300 				    ALTERA_AVALON_FLAG_MMAP_WRITE;
301 				break;
302 
303 			case ALTERA_AVALON_CHAR_EXEC:
304 				sc->avg_flags |= ALTERA_AVALON_FLAG_MMAP_EXEC;
305 				break;
306 
307 			default:
308 				device_printf(dev,
309 				    "invalid %s character %c\n",
310 				    ALTERA_AVALON_STR_MMAPIO, *cp);
311 				return (ENXIO);
312 			}
313 		}
314 	}
315 	return (0);
316 }
317 
318 int
319 altera_avgen_attach(struct altera_avgen_softc *sc, const char *str_fileio,
320     const char *str_mmapio, const char *str_devname, int devunit)
321 {
322 	device_t dev = sc->avg_dev;
323 	int error;
324 
325 	error = altera_avgen_process_options(sc, str_fileio, str_mmapio,
326 	    str_devname, devunit);
327 	if (error)
328 		return (error);
329 
330 	if (rman_get_size(sc->avg_res) >= PAGE_SIZE || str_mmapio != NULL) {
331 		if (rman_get_size(sc->avg_res) % PAGE_SIZE != 0) {
332 			device_printf(dev,
333 			    "memory region not even multiple of page size\n");
334 			return (ENXIO);
335 		}
336 		if (rman_get_start(sc->avg_res) % PAGE_SIZE != 0) {
337 			device_printf(dev, "memory region not page-aligned\n");
338 			return (ENXIO);
339 		}
340 	}
341 
342 	/* Device node allocation. */
343 	if (str_devname == NULL) {
344 		str_devname = "altera_avgen%d";
345 		devunit = sc->avg_unit;
346 	}
347 	if (devunit != -1)
348 		sc->avg_cdev = make_dev(&avg_cdevsw, sc->avg_unit, UID_ROOT,
349 		    GID_WHEEL, S_IRUSR | S_IWUSR, str_devname, devunit);
350 	else
351 		sc->avg_cdev = make_dev(&avg_cdevsw, sc->avg_unit, UID_ROOT,
352 		    GID_WHEEL, S_IRUSR | S_IWUSR, str_devname);
353 	if (sc->avg_cdev == NULL) {
354 		device_printf(sc->avg_dev, "%s: make_dev failed\n", __func__);
355 		return (ENXIO);
356 	}
357 	/* XXXRW: Slight race between make_dev(9) and here. */
358 	sc->avg_cdev->si_drv1 = sc;
359 	return (0);
360 }
361 
362 void
363 altera_avgen_detach(struct altera_avgen_softc *sc)
364 {
365 
366 	destroy_dev(sc->avg_cdev);
367 }
368