xref: /dpdk/drivers/bus/pci/linux/pci_uio.c (revision 5ecb687a5698d2d8ec1f3b3b5a7a16bceca3e29c)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4 
5 #include <string.h>
6 #include <unistd.h>
7 #include <fcntl.h>
8 #include <dirent.h>
9 #include <inttypes.h>
10 #include <sys/stat.h>
11 #include <sys/mman.h>
12 #include <sys/sysmacros.h>
13 #include <linux/pci_regs.h>
14 
15 #if defined(RTE_ARCH_X86)
16 #include <sys/io.h>
17 #endif
18 
19 #include <rte_string_fns.h>
20 #include <rte_log.h>
21 #include <rte_pci.h>
22 #include <rte_bus_pci.h>
23 #include <rte_eal_memconfig.h>
24 #include <rte_common.h>
25 #include <rte_malloc.h>
26 
27 #include "eal_filesystem.h"
28 #include "pci_init.h"
29 
30 void *pci_map_addr = NULL;
31 
32 #define OFF_MAX              ((uint64_t)(off_t)-1)
33 
34 int
35 pci_uio_read_config(const struct rte_intr_handle *intr_handle,
36 		    void *buf, size_t len, off_t offset)
37 {
38 	return pread(intr_handle->uio_cfg_fd, buf, len, offset);
39 }
40 
41 int
42 pci_uio_write_config(const struct rte_intr_handle *intr_handle,
43 		     const void *buf, size_t len, off_t offset)
44 {
45 	return pwrite(intr_handle->uio_cfg_fd, buf, len, offset);
46 }
47 
48 static int
49 pci_uio_set_bus_master(int dev_fd)
50 {
51 	uint16_t reg;
52 	int ret;
53 
54 	ret = pread(dev_fd, &reg, sizeof(reg), PCI_COMMAND);
55 	if (ret != sizeof(reg)) {
56 		RTE_LOG(ERR, EAL,
57 			"Cannot read command from PCI config space!\n");
58 		return -1;
59 	}
60 
61 	/* return if bus mastering is already on */
62 	if (reg & PCI_COMMAND_MASTER)
63 		return 0;
64 
65 	reg |= PCI_COMMAND_MASTER;
66 
67 	ret = pwrite(dev_fd, &reg, sizeof(reg), PCI_COMMAND);
68 	if (ret != sizeof(reg)) {
69 		RTE_LOG(ERR, EAL,
70 			"Cannot write command to PCI config space!\n");
71 		return -1;
72 	}
73 
74 	return 0;
75 }
76 
77 static int
78 pci_mknod_uio_dev(const char *sysfs_uio_path, unsigned uio_num)
79 {
80 	FILE *f;
81 	char filename[PATH_MAX];
82 	int ret;
83 	unsigned major, minor;
84 	dev_t dev;
85 
86 	/* get the name of the sysfs file that contains the major and minor
87 	 * of the uio device and read its content */
88 	snprintf(filename, sizeof(filename), "%s/dev", sysfs_uio_path);
89 
90 	f = fopen(filename, "r");
91 	if (f == NULL) {
92 		RTE_LOG(ERR, EAL, "%s(): cannot open sysfs to get major:minor\n",
93 			__func__);
94 		return -1;
95 	}
96 
97 	ret = fscanf(f, "%u:%u", &major, &minor);
98 	if (ret != 2) {
99 		RTE_LOG(ERR, EAL, "%s(): cannot parse sysfs to get major:minor\n",
100 			__func__);
101 		fclose(f);
102 		return -1;
103 	}
104 	fclose(f);
105 
106 	/* create the char device "mknod /dev/uioX c major minor" */
107 	snprintf(filename, sizeof(filename), "/dev/uio%u", uio_num);
108 	dev = makedev(major, minor);
109 	ret = mknod(filename, S_IFCHR | S_IRUSR | S_IWUSR, dev);
110 	if (ret != 0) {
111 		RTE_LOG(ERR, EAL, "%s(): mknod() failed %s\n",
112 			__func__, strerror(errno));
113 		return -1;
114 	}
115 
116 	return ret;
117 }
118 
119 /*
120  * Return the uioX char device used for a pci device. On success, return
121  * the UIO number and fill dstbuf string with the path of the device in
122  * sysfs. On error, return a negative value. In this case dstbuf is
123  * invalid.
124  */
125 static int
126 pci_get_uio_dev(struct rte_pci_device *dev, char *dstbuf,
127 			   unsigned int buflen, int create)
128 {
129 	struct rte_pci_addr *loc = &dev->addr;
130 	int uio_num = -1;
131 	struct dirent *e;
132 	DIR *dir;
133 	char dirname[PATH_MAX];
134 
135 	/* depending on kernel version, uio can be located in uio/uioX
136 	 * or uio:uioX */
137 
138 	snprintf(dirname, sizeof(dirname),
139 			"%s/" PCI_PRI_FMT "/uio", rte_pci_get_sysfs_path(),
140 			loc->domain, loc->bus, loc->devid, loc->function);
141 
142 	dir = opendir(dirname);
143 	if (dir == NULL) {
144 		/* retry with the parent directory */
145 		snprintf(dirname, sizeof(dirname),
146 				"%s/" PCI_PRI_FMT, rte_pci_get_sysfs_path(),
147 				loc->domain, loc->bus, loc->devid, loc->function);
148 		dir = opendir(dirname);
149 
150 		if (dir == NULL) {
151 			RTE_LOG(ERR, EAL, "Cannot opendir %s\n", dirname);
152 			return -1;
153 		}
154 	}
155 
156 	/* take the first file starting with "uio" */
157 	while ((e = readdir(dir)) != NULL) {
158 		/* format could be uio%d ...*/
159 		int shortprefix_len = sizeof("uio") - 1;
160 		/* ... or uio:uio%d */
161 		int longprefix_len = sizeof("uio:uio") - 1;
162 		char *endptr;
163 
164 		if (strncmp(e->d_name, "uio", 3) != 0)
165 			continue;
166 
167 		/* first try uio%d */
168 		errno = 0;
169 		uio_num = strtoull(e->d_name + shortprefix_len, &endptr, 10);
170 		if (errno == 0 && endptr != (e->d_name + shortprefix_len)) {
171 			snprintf(dstbuf, buflen, "%s/uio%u", dirname, uio_num);
172 			break;
173 		}
174 
175 		/* then try uio:uio%d */
176 		errno = 0;
177 		uio_num = strtoull(e->d_name + longprefix_len, &endptr, 10);
178 		if (errno == 0 && endptr != (e->d_name + longprefix_len)) {
179 			snprintf(dstbuf, buflen, "%s/uio:uio%u", dirname, uio_num);
180 			break;
181 		}
182 	}
183 	closedir(dir);
184 
185 	/* No uio resource found */
186 	if (e == NULL)
187 		return -1;
188 
189 	/* create uio device if we've been asked to */
190 	if (rte_eal_create_uio_dev() && create &&
191 			pci_mknod_uio_dev(dstbuf, uio_num) < 0)
192 		RTE_LOG(WARNING, EAL, "Cannot create /dev/uio%u\n", uio_num);
193 
194 	return uio_num;
195 }
196 
197 void
198 pci_uio_free_resource(struct rte_pci_device *dev,
199 		struct mapped_pci_resource *uio_res)
200 {
201 	rte_free(uio_res);
202 
203 	if (dev->intr_handle.uio_cfg_fd >= 0) {
204 		close(dev->intr_handle.uio_cfg_fd);
205 		dev->intr_handle.uio_cfg_fd = -1;
206 	}
207 	if (dev->intr_handle.fd >= 0) {
208 		close(dev->intr_handle.fd);
209 		dev->intr_handle.fd = -1;
210 		dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
211 	}
212 }
213 
214 int
215 pci_uio_alloc_resource(struct rte_pci_device *dev,
216 		struct mapped_pci_resource **uio_res)
217 {
218 	char dirname[PATH_MAX];
219 	char cfgname[PATH_MAX];
220 	char devname[PATH_MAX]; /* contains the /dev/uioX */
221 	int uio_num;
222 	struct rte_pci_addr *loc;
223 
224 	loc = &dev->addr;
225 
226 	/* find uio resource */
227 	uio_num = pci_get_uio_dev(dev, dirname, sizeof(dirname), 1);
228 	if (uio_num < 0) {
229 		RTE_LOG(WARNING, EAL, "  "PCI_PRI_FMT" not managed by UIO driver, "
230 				"skipping\n", loc->domain, loc->bus, loc->devid, loc->function);
231 		return 1;
232 	}
233 	snprintf(devname, sizeof(devname), "/dev/uio%u", uio_num);
234 
235 	/* save fd if in primary process */
236 	dev->intr_handle.fd = open(devname, O_RDWR);
237 	if (dev->intr_handle.fd < 0) {
238 		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
239 			devname, strerror(errno));
240 		goto error;
241 	}
242 
243 	snprintf(cfgname, sizeof(cfgname),
244 			"/sys/class/uio/uio%u/device/config", uio_num);
245 	dev->intr_handle.uio_cfg_fd = open(cfgname, O_RDWR);
246 	if (dev->intr_handle.uio_cfg_fd < 0) {
247 		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
248 			cfgname, strerror(errno));
249 		goto error;
250 	}
251 
252 	if (dev->kdrv == RTE_KDRV_IGB_UIO)
253 		dev->intr_handle.type = RTE_INTR_HANDLE_UIO;
254 	else {
255 		dev->intr_handle.type = RTE_INTR_HANDLE_UIO_INTX;
256 
257 		/* set bus master that is not done by uio_pci_generic */
258 		if (pci_uio_set_bus_master(dev->intr_handle.uio_cfg_fd)) {
259 			RTE_LOG(ERR, EAL, "Cannot set up bus mastering!\n");
260 			goto error;
261 		}
262 	}
263 
264 	/* allocate the mapping details for secondary processes*/
265 	*uio_res = rte_zmalloc("UIO_RES", sizeof(**uio_res), 0);
266 	if (*uio_res == NULL) {
267 		RTE_LOG(ERR, EAL,
268 			"%s(): cannot store uio mmap details\n", __func__);
269 		goto error;
270 	}
271 
272 	strlcpy((*uio_res)->path, devname, sizeof((*uio_res)->path));
273 	memcpy(&(*uio_res)->pci_addr, &dev->addr, sizeof((*uio_res)->pci_addr));
274 
275 	return 0;
276 
277 error:
278 	pci_uio_free_resource(dev, *uio_res);
279 	return -1;
280 }
281 
282 int
283 pci_uio_map_resource_by_index(struct rte_pci_device *dev, int res_idx,
284 		struct mapped_pci_resource *uio_res, int map_idx)
285 {
286 	int fd = -1;
287 	char devname[PATH_MAX];
288 	void *mapaddr;
289 	struct rte_pci_addr *loc;
290 	struct pci_map *maps;
291 	int wc_activate = 0;
292 
293 	if (dev->driver != NULL)
294 		wc_activate = dev->driver->drv_flags & RTE_PCI_DRV_WC_ACTIVATE;
295 
296 	loc = &dev->addr;
297 	maps = uio_res->maps;
298 
299 	/* allocate memory to keep path */
300 	maps[map_idx].path = rte_malloc(NULL, sizeof(devname), 0);
301 	if (maps[map_idx].path == NULL) {
302 		RTE_LOG(ERR, EAL, "Cannot allocate memory for path: %s\n",
303 				strerror(errno));
304 		return -1;
305 	}
306 
307 	/*
308 	 * open resource file, to mmap it
309 	 */
310 	if (wc_activate) {
311 		/* update devname for mmap  */
312 		snprintf(devname, sizeof(devname),
313 			"%s/" PCI_PRI_FMT "/resource%d_wc",
314 			rte_pci_get_sysfs_path(),
315 			loc->domain, loc->bus, loc->devid,
316 			loc->function, res_idx);
317 
318 		if (access(devname, R_OK|W_OK) != -1) {
319 			fd = open(devname, O_RDWR);
320 			if (fd < 0)
321 				RTE_LOG(INFO, EAL, "%s cannot be mapped. "
322 					"Fall-back to non prefetchable mode.\n",
323 					devname);
324 		}
325 	}
326 
327 	if (!wc_activate || fd < 0) {
328 		snprintf(devname, sizeof(devname),
329 			"%s/" PCI_PRI_FMT "/resource%d",
330 			rte_pci_get_sysfs_path(),
331 			loc->domain, loc->bus, loc->devid,
332 			loc->function, res_idx);
333 
334 		/* then try to map resource file */
335 		fd = open(devname, O_RDWR);
336 		if (fd < 0) {
337 			RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
338 				devname, strerror(errno));
339 			goto error;
340 		}
341 	}
342 
343 	/* try mapping somewhere close to the end of hugepages */
344 	if (pci_map_addr == NULL)
345 		pci_map_addr = pci_find_max_end_va();
346 
347 	mapaddr = pci_map_resource(pci_map_addr, fd, 0,
348 			(size_t)dev->mem_resource[res_idx].len, 0);
349 	close(fd);
350 	if (mapaddr == MAP_FAILED)
351 		goto error;
352 
353 	pci_map_addr = RTE_PTR_ADD(mapaddr,
354 			(size_t)dev->mem_resource[res_idx].len);
355 
356 	maps[map_idx].phaddr = dev->mem_resource[res_idx].phys_addr;
357 	maps[map_idx].size = dev->mem_resource[res_idx].len;
358 	maps[map_idx].addr = mapaddr;
359 	maps[map_idx].offset = 0;
360 	strcpy(maps[map_idx].path, devname);
361 	dev->mem_resource[res_idx].addr = mapaddr;
362 
363 	return 0;
364 
365 error:
366 	rte_free(maps[map_idx].path);
367 	return -1;
368 }
369 
370 #if defined(RTE_ARCH_X86)
371 int
372 pci_uio_ioport_map(struct rte_pci_device *dev, int bar,
373 		   struct rte_pci_ioport *p)
374 {
375 	char dirname[PATH_MAX];
376 	char filename[PATH_MAX];
377 	int uio_num;
378 	unsigned long start;
379 
380 	uio_num = pci_get_uio_dev(dev, dirname, sizeof(dirname), 0);
381 	if (uio_num < 0)
382 		return -1;
383 
384 	/* get portio start */
385 	snprintf(filename, sizeof(filename),
386 		 "%s/portio/port%d/start", dirname, bar);
387 	if (eal_parse_sysfs_value(filename, &start) < 0) {
388 		RTE_LOG(ERR, EAL, "%s(): cannot parse portio start\n",
389 			__func__);
390 		return -1;
391 	}
392 	/* ensure we don't get anything funny here, read/write will cast to
393 	 * uin16_t */
394 	if (start > UINT16_MAX)
395 		return -1;
396 
397 	/* FIXME only for primary process ? */
398 	if (dev->intr_handle.type == RTE_INTR_HANDLE_UNKNOWN) {
399 
400 		snprintf(filename, sizeof(filename), "/dev/uio%u", uio_num);
401 		dev->intr_handle.fd = open(filename, O_RDWR);
402 		if (dev->intr_handle.fd < 0) {
403 			RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
404 				filename, strerror(errno));
405 			return -1;
406 		}
407 		dev->intr_handle.type = RTE_INTR_HANDLE_UIO;
408 	}
409 
410 	RTE_LOG(DEBUG, EAL, "PCI Port IO found start=0x%lx\n", start);
411 
412 	p->base = start;
413 	p->len = 0;
414 	return 0;
415 }
416 #else
417 int
418 pci_uio_ioport_map(struct rte_pci_device *dev, int bar,
419 		   struct rte_pci_ioport *p)
420 {
421 	FILE *f;
422 	char buf[BUFSIZ];
423 	char filename[PATH_MAX];
424 	uint64_t phys_addr, end_addr, flags;
425 	int fd, i;
426 	void *addr;
427 
428 	/* open and read addresses of the corresponding resource in sysfs */
429 	snprintf(filename, sizeof(filename), "%s/" PCI_PRI_FMT "/resource",
430 		rte_pci_get_sysfs_path(), dev->addr.domain, dev->addr.bus,
431 		dev->addr.devid, dev->addr.function);
432 	f = fopen(filename, "r");
433 	if (f == NULL) {
434 		RTE_LOG(ERR, EAL, "Cannot open sysfs resource: %s\n",
435 			strerror(errno));
436 		return -1;
437 	}
438 	for (i = 0; i < bar + 1; i++) {
439 		if (fgets(buf, sizeof(buf), f) == NULL) {
440 			RTE_LOG(ERR, EAL, "Cannot read sysfs resource\n");
441 			goto error;
442 		}
443 	}
444 	if (pci_parse_one_sysfs_resource(buf, sizeof(buf), &phys_addr,
445 			&end_addr, &flags) < 0)
446 		goto error;
447 	if ((flags & IORESOURCE_IO) == 0) {
448 		RTE_LOG(ERR, EAL, "BAR %d is not an IO resource\n", bar);
449 		goto error;
450 	}
451 	snprintf(filename, sizeof(filename), "%s/" PCI_PRI_FMT "/resource%d",
452 		rte_pci_get_sysfs_path(), dev->addr.domain, dev->addr.bus,
453 		dev->addr.devid, dev->addr.function, bar);
454 
455 	/* mmap the pci resource */
456 	fd = open(filename, O_RDWR);
457 	if (fd < 0) {
458 		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n", filename,
459 			strerror(errno));
460 		goto error;
461 	}
462 	addr = mmap(NULL, end_addr + 1, PROT_READ | PROT_WRITE,
463 		MAP_SHARED, fd, 0);
464 	close(fd);
465 	if (addr == MAP_FAILED) {
466 		RTE_LOG(ERR, EAL, "Cannot mmap IO port resource: %s\n",
467 			strerror(errno));
468 		goto error;
469 	}
470 
471 	/* strangely, the base address is mmap addr + phys_addr */
472 	p->base = (uintptr_t)addr + phys_addr;
473 	p->len = end_addr + 1;
474 	RTE_LOG(DEBUG, EAL, "PCI Port IO found start=0x%"PRIx64"\n", p->base);
475 	fclose(f);
476 
477 	return 0;
478 
479 error:
480 	fclose(f);
481 	return -1;
482 }
483 #endif
484 
485 void
486 pci_uio_ioport_read(struct rte_pci_ioport *p,
487 		    void *data, size_t len, off_t offset)
488 {
489 	uint8_t *d;
490 	int size;
491 	uintptr_t reg = p->base + offset;
492 
493 	for (d = data; len > 0; d += size, reg += size, len -= size) {
494 		if (len >= 4) {
495 			size = 4;
496 #if defined(RTE_ARCH_X86)
497 			*(uint32_t *)d = inl(reg);
498 #else
499 			*(uint32_t *)d = *(volatile uint32_t *)reg;
500 #endif
501 		} else if (len >= 2) {
502 			size = 2;
503 #if defined(RTE_ARCH_X86)
504 			*(uint16_t *)d = inw(reg);
505 #else
506 			*(uint16_t *)d = *(volatile uint16_t *)reg;
507 #endif
508 		} else {
509 			size = 1;
510 #if defined(RTE_ARCH_X86)
511 			*d = inb(reg);
512 #else
513 			*d = *(volatile uint8_t *)reg;
514 #endif
515 		}
516 	}
517 }
518 
519 void
520 pci_uio_ioport_write(struct rte_pci_ioport *p,
521 		     const void *data, size_t len, off_t offset)
522 {
523 	const uint8_t *s;
524 	int size;
525 	uintptr_t reg = p->base + offset;
526 
527 	for (s = data; len > 0; s += size, reg += size, len -= size) {
528 		if (len >= 4) {
529 			size = 4;
530 #if defined(RTE_ARCH_X86)
531 			outl_p(*(const uint32_t *)s, reg);
532 #else
533 			*(volatile uint32_t *)reg = *(const uint32_t *)s;
534 #endif
535 		} else if (len >= 2) {
536 			size = 2;
537 #if defined(RTE_ARCH_X86)
538 			outw_p(*(const uint16_t *)s, reg);
539 #else
540 			*(volatile uint16_t *)reg = *(const uint16_t *)s;
541 #endif
542 		} else {
543 			size = 1;
544 #if defined(RTE_ARCH_X86)
545 			outb_p(*s, reg);
546 #else
547 			*(volatile uint8_t *)reg = *s;
548 #endif
549 		}
550 	}
551 }
552 
553 int
554 pci_uio_ioport_unmap(struct rte_pci_ioport *p)
555 {
556 #if defined(RTE_ARCH_X86)
557 	RTE_SET_USED(p);
558 	/* FIXME close intr fd ? */
559 	return 0;
560 #else
561 	return munmap((void *)(uintptr_t)p->base, p->len);
562 #endif
563 }
564