xref: /dpdk/drivers/bus/pci/linux/pci_uio.c (revision f43d3dbbd90c9e195d26d18ac7da9ca2854c3f1e)
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_common.h>
24 #include <rte_malloc.h>
25 
26 #include "eal_filesystem.h"
27 #include "pci_init.h"
28 
29 void *pci_map_addr = NULL;
30 
31 #define OFF_MAX              ((uint64_t)(off_t)-1)
32 
33 int
34 pci_uio_read_config(const struct rte_intr_handle *intr_handle,
35 		    void *buf, size_t len, off_t offset)
36 {
37 	return pread(intr_handle->uio_cfg_fd, buf, len, offset);
38 }
39 
40 int
41 pci_uio_write_config(const struct rte_intr_handle *intr_handle,
42 		     const void *buf, size_t len, off_t offset)
43 {
44 	return pwrite(intr_handle->uio_cfg_fd, buf, len, offset);
45 }
46 
47 static int
48 pci_uio_set_bus_master(int dev_fd)
49 {
50 	uint16_t reg;
51 	int ret;
52 
53 	ret = pread(dev_fd, &reg, sizeof(reg), PCI_COMMAND);
54 	if (ret != sizeof(reg)) {
55 		RTE_LOG(ERR, EAL,
56 			"Cannot read command from PCI config space!\n");
57 		return -1;
58 	}
59 
60 	/* return if bus mastering is already on */
61 	if (reg & PCI_COMMAND_MASTER)
62 		return 0;
63 
64 	reg |= PCI_COMMAND_MASTER;
65 
66 	ret = pwrite(dev_fd, &reg, sizeof(reg), PCI_COMMAND);
67 	if (ret != sizeof(reg)) {
68 		RTE_LOG(ERR, EAL,
69 			"Cannot write command to PCI config space!\n");
70 		return -1;
71 	}
72 
73 	return 0;
74 }
75 
76 static int
77 pci_mknod_uio_dev(const char *sysfs_uio_path, unsigned uio_num)
78 {
79 	FILE *f;
80 	char filename[PATH_MAX];
81 	int ret;
82 	unsigned major, minor;
83 	dev_t dev;
84 
85 	/* get the name of the sysfs file that contains the major and minor
86 	 * of the uio device and read its content */
87 	snprintf(filename, sizeof(filename), "%s/dev", sysfs_uio_path);
88 
89 	f = fopen(filename, "r");
90 	if (f == NULL) {
91 		RTE_LOG(ERR, EAL, "%s(): cannot open sysfs to get major:minor\n",
92 			__func__);
93 		return -1;
94 	}
95 
96 	ret = fscanf(f, "%u:%u", &major, &minor);
97 	if (ret != 2) {
98 		RTE_LOG(ERR, EAL, "%s(): cannot parse sysfs to get major:minor\n",
99 			__func__);
100 		fclose(f);
101 		return -1;
102 	}
103 	fclose(f);
104 
105 	/* create the char device "mknod /dev/uioX c major minor" */
106 	snprintf(filename, sizeof(filename), "/dev/uio%u", uio_num);
107 	dev = makedev(major, minor);
108 	ret = mknod(filename, S_IFCHR | S_IRUSR | S_IWUSR, dev);
109 	if (ret != 0) {
110 		RTE_LOG(ERR, EAL, "%s(): mknod() failed %s\n",
111 			__func__, strerror(errno));
112 		return -1;
113 	}
114 
115 	return ret;
116 }
117 
118 /*
119  * Return the uioX char device used for a pci device. On success, return
120  * the UIO number and fill dstbuf string with the path of the device in
121  * sysfs. On error, return a negative value. In this case dstbuf is
122  * invalid.
123  */
124 static int
125 pci_get_uio_dev(struct rte_pci_device *dev, char *dstbuf,
126 			   unsigned int buflen, int create)
127 {
128 	struct rte_pci_addr *loc = &dev->addr;
129 	int uio_num = -1;
130 	struct dirent *e;
131 	DIR *dir;
132 	char dirname[PATH_MAX];
133 
134 	/* depending on kernel version, uio can be located in uio/uioX
135 	 * or uio:uioX */
136 
137 	snprintf(dirname, sizeof(dirname),
138 			"%s/" PCI_PRI_FMT "/uio", rte_pci_get_sysfs_path(),
139 			loc->domain, loc->bus, loc->devid, loc->function);
140 
141 	dir = opendir(dirname);
142 	if (dir == NULL) {
143 		/* retry with the parent directory */
144 		snprintf(dirname, sizeof(dirname),
145 				"%s/" PCI_PRI_FMT, rte_pci_get_sysfs_path(),
146 				loc->domain, loc->bus, loc->devid, loc->function);
147 		dir = opendir(dirname);
148 
149 		if (dir == NULL) {
150 			RTE_LOG(ERR, EAL, "Cannot opendir %s\n", dirname);
151 			return -1;
152 		}
153 	}
154 
155 	/* take the first file starting with "uio" */
156 	while ((e = readdir(dir)) != NULL) {
157 		/* format could be uio%d ...*/
158 		int shortprefix_len = sizeof("uio") - 1;
159 		/* ... or uio:uio%d */
160 		int longprefix_len = sizeof("uio:uio") - 1;
161 		char *endptr;
162 
163 		if (strncmp(e->d_name, "uio", 3) != 0)
164 			continue;
165 
166 		/* first try uio%d */
167 		errno = 0;
168 		uio_num = strtoull(e->d_name + shortprefix_len, &endptr, 10);
169 		if (errno == 0 && endptr != (e->d_name + shortprefix_len)) {
170 			snprintf(dstbuf, buflen, "%s/uio%u", dirname, uio_num);
171 			break;
172 		}
173 
174 		/* then try uio:uio%d */
175 		errno = 0;
176 		uio_num = strtoull(e->d_name + longprefix_len, &endptr, 10);
177 		if (errno == 0 && endptr != (e->d_name + longprefix_len)) {
178 			snprintf(dstbuf, buflen, "%s/uio:uio%u", dirname, uio_num);
179 			break;
180 		}
181 	}
182 	closedir(dir);
183 
184 	/* No uio resource found */
185 	if (e == NULL)
186 		return -1;
187 
188 	/* create uio device if we've been asked to */
189 	if (rte_eal_create_uio_dev() && create &&
190 			pci_mknod_uio_dev(dstbuf, uio_num) < 0)
191 		RTE_LOG(WARNING, EAL, "Cannot create /dev/uio%u\n", uio_num);
192 
193 	return uio_num;
194 }
195 
196 void
197 pci_uio_free_resource(struct rte_pci_device *dev,
198 		struct mapped_pci_resource *uio_res)
199 {
200 	rte_free(uio_res);
201 
202 	if (dev->intr_handle.uio_cfg_fd >= 0) {
203 		close(dev->intr_handle.uio_cfg_fd);
204 		dev->intr_handle.uio_cfg_fd = -1;
205 	}
206 	if (dev->intr_handle.fd >= 0) {
207 		close(dev->intr_handle.fd);
208 		dev->intr_handle.fd = -1;
209 		dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
210 	}
211 }
212 
213 int
214 pci_uio_alloc_resource(struct rte_pci_device *dev,
215 		struct mapped_pci_resource **uio_res)
216 {
217 	char dirname[PATH_MAX];
218 	char cfgname[PATH_MAX];
219 	char devname[PATH_MAX]; /* contains the /dev/uioX */
220 	int uio_num;
221 	struct rte_pci_addr *loc;
222 
223 	loc = &dev->addr;
224 
225 	/* find uio resource */
226 	uio_num = pci_get_uio_dev(dev, dirname, sizeof(dirname), 1);
227 	if (uio_num < 0) {
228 		RTE_LOG(WARNING, EAL, "  "PCI_PRI_FMT" not managed by UIO driver, "
229 				"skipping\n", loc->domain, loc->bus, loc->devid, loc->function);
230 		return 1;
231 	}
232 	snprintf(devname, sizeof(devname), "/dev/uio%u", uio_num);
233 
234 	/* save fd if in primary process */
235 	dev->intr_handle.fd = open(devname, O_RDWR);
236 	if (dev->intr_handle.fd < 0) {
237 		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
238 			devname, strerror(errno));
239 		goto error;
240 	}
241 
242 	snprintf(cfgname, sizeof(cfgname),
243 			"/sys/class/uio/uio%u/device/config", uio_num);
244 	dev->intr_handle.uio_cfg_fd = open(cfgname, O_RDWR);
245 	if (dev->intr_handle.uio_cfg_fd < 0) {
246 		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
247 			cfgname, strerror(errno));
248 		goto error;
249 	}
250 
251 	if (dev->kdrv == RTE_KDRV_IGB_UIO)
252 		dev->intr_handle.type = RTE_INTR_HANDLE_UIO;
253 	else {
254 		dev->intr_handle.type = RTE_INTR_HANDLE_UIO_INTX;
255 
256 		/* set bus master that is not done by uio_pci_generic */
257 		if (pci_uio_set_bus_master(dev->intr_handle.uio_cfg_fd)) {
258 			RTE_LOG(ERR, EAL, "Cannot set up bus mastering!\n");
259 			goto error;
260 		}
261 	}
262 
263 	/* allocate the mapping details for secondary processes*/
264 	*uio_res = rte_zmalloc("UIO_RES", sizeof(**uio_res), 0);
265 	if (*uio_res == NULL) {
266 		RTE_LOG(ERR, EAL,
267 			"%s(): cannot store uio mmap details\n", __func__);
268 		goto error;
269 	}
270 
271 	strlcpy((*uio_res)->path, devname, sizeof((*uio_res)->path));
272 	memcpy(&(*uio_res)->pci_addr, &dev->addr, sizeof((*uio_res)->pci_addr));
273 
274 	return 0;
275 
276 error:
277 	pci_uio_free_resource(dev, *uio_res);
278 	return -1;
279 }
280 
281 int
282 pci_uio_map_resource_by_index(struct rte_pci_device *dev, int res_idx,
283 		struct mapped_pci_resource *uio_res, int map_idx)
284 {
285 	int fd = -1;
286 	char devname[PATH_MAX];
287 	void *mapaddr;
288 	struct rte_pci_addr *loc;
289 	struct pci_map *maps;
290 	int wc_activate = 0;
291 
292 	if (dev->driver != NULL)
293 		wc_activate = dev->driver->drv_flags & RTE_PCI_DRV_WC_ACTIVATE;
294 
295 	loc = &dev->addr;
296 	maps = uio_res->maps;
297 
298 	/* allocate memory to keep path */
299 	maps[map_idx].path = rte_malloc(NULL, sizeof(devname), 0);
300 	if (maps[map_idx].path == NULL) {
301 		RTE_LOG(ERR, EAL, "Cannot allocate memory for path: %s\n",
302 				strerror(errno));
303 		return -1;
304 	}
305 
306 	/*
307 	 * open resource file, to mmap it
308 	 */
309 	if (wc_activate) {
310 		/* update devname for mmap  */
311 		snprintf(devname, sizeof(devname),
312 			"%s/" PCI_PRI_FMT "/resource%d_wc",
313 			rte_pci_get_sysfs_path(),
314 			loc->domain, loc->bus, loc->devid,
315 			loc->function, res_idx);
316 
317 		fd = open(devname, O_RDWR);
318 		if (fd < 0 && errno != ENOENT) {
319 			RTE_LOG(INFO, EAL, "%s cannot be mapped. "
320 				"Fall-back to non prefetchable mode.\n",
321 				devname);
322 		}
323 	}
324 
325 	if (!wc_activate || fd < 0) {
326 		snprintf(devname, sizeof(devname),
327 			"%s/" PCI_PRI_FMT "/resource%d",
328 			rte_pci_get_sysfs_path(),
329 			loc->domain, loc->bus, loc->devid,
330 			loc->function, res_idx);
331 
332 		/* then try to map resource file */
333 		fd = open(devname, O_RDWR);
334 		if (fd < 0) {
335 			RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
336 				devname, strerror(errno));
337 			goto error;
338 		}
339 	}
340 
341 	/* try mapping somewhere close to the end of hugepages */
342 	if (pci_map_addr == NULL)
343 		pci_map_addr = pci_find_max_end_va();
344 
345 	mapaddr = pci_map_resource(pci_map_addr, fd, 0,
346 			(size_t)dev->mem_resource[res_idx].len, 0);
347 	close(fd);
348 	if (mapaddr == MAP_FAILED)
349 		goto error;
350 
351 	pci_map_addr = RTE_PTR_ADD(mapaddr,
352 			(size_t)dev->mem_resource[res_idx].len);
353 
354 	pci_map_addr = RTE_PTR_ALIGN(pci_map_addr, sysconf(_SC_PAGE_SIZE));
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 	if (rte_eal_iopl_init() != 0) {
381 		RTE_LOG(ERR, EAL, "%s(): insufficient ioport permissions for PCI device %s\n",
382 			__func__, dev->name);
383 		return -1;
384 	}
385 
386 	uio_num = pci_get_uio_dev(dev, dirname, sizeof(dirname), 0);
387 	if (uio_num < 0)
388 		return -1;
389 
390 	/* get portio start */
391 	snprintf(filename, sizeof(filename),
392 		 "%s/portio/port%d/start", dirname, bar);
393 	if (eal_parse_sysfs_value(filename, &start) < 0) {
394 		RTE_LOG(ERR, EAL, "%s(): cannot parse portio start\n",
395 			__func__);
396 		return -1;
397 	}
398 	/* ensure we don't get anything funny here, read/write will cast to
399 	 * uin16_t */
400 	if (start > UINT16_MAX)
401 		return -1;
402 
403 	/* FIXME only for primary process ? */
404 	if (dev->intr_handle.type == RTE_INTR_HANDLE_UNKNOWN) {
405 
406 		snprintf(filename, sizeof(filename), "/dev/uio%u", uio_num);
407 		dev->intr_handle.fd = open(filename, O_RDWR);
408 		if (dev->intr_handle.fd < 0) {
409 			RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
410 				filename, strerror(errno));
411 			return -1;
412 		}
413 		dev->intr_handle.type = RTE_INTR_HANDLE_UIO;
414 	}
415 
416 	RTE_LOG(DEBUG, EAL, "PCI Port IO found start=0x%lx\n", start);
417 
418 	p->base = start;
419 	p->len = 0;
420 	return 0;
421 }
422 #else
423 int
424 pci_uio_ioport_map(struct rte_pci_device *dev, int bar,
425 		   struct rte_pci_ioport *p)
426 {
427 	FILE *f;
428 	char buf[BUFSIZ];
429 	char filename[PATH_MAX];
430 	uint64_t phys_addr, end_addr, flags;
431 	int fd, i;
432 	void *addr;
433 
434 	/* open and read addresses of the corresponding resource in sysfs */
435 	snprintf(filename, sizeof(filename), "%s/" PCI_PRI_FMT "/resource",
436 		rte_pci_get_sysfs_path(), dev->addr.domain, dev->addr.bus,
437 		dev->addr.devid, dev->addr.function);
438 	f = fopen(filename, "r");
439 	if (f == NULL) {
440 		RTE_LOG(ERR, EAL, "Cannot open sysfs resource: %s\n",
441 			strerror(errno));
442 		return -1;
443 	}
444 	for (i = 0; i < bar + 1; i++) {
445 		if (fgets(buf, sizeof(buf), f) == NULL) {
446 			RTE_LOG(ERR, EAL, "Cannot read sysfs resource\n");
447 			goto error;
448 		}
449 	}
450 	if (pci_parse_one_sysfs_resource(buf, sizeof(buf), &phys_addr,
451 			&end_addr, &flags) < 0)
452 		goto error;
453 	if ((flags & IORESOURCE_IO) == 0) {
454 		RTE_LOG(ERR, EAL, "BAR %d is not an IO resource\n", bar);
455 		goto error;
456 	}
457 	snprintf(filename, sizeof(filename), "%s/" PCI_PRI_FMT "/resource%d",
458 		rte_pci_get_sysfs_path(), dev->addr.domain, dev->addr.bus,
459 		dev->addr.devid, dev->addr.function, bar);
460 
461 	/* mmap the pci resource */
462 	fd = open(filename, O_RDWR);
463 	if (fd < 0) {
464 		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n", filename,
465 			strerror(errno));
466 		goto error;
467 	}
468 	addr = mmap(NULL, end_addr + 1, PROT_READ | PROT_WRITE,
469 		MAP_SHARED, fd, 0);
470 	close(fd);
471 	if (addr == MAP_FAILED) {
472 		RTE_LOG(ERR, EAL, "Cannot mmap IO port resource: %s\n",
473 			strerror(errno));
474 		goto error;
475 	}
476 
477 	/* strangely, the base address is mmap addr + phys_addr */
478 	p->base = (uintptr_t)addr + phys_addr;
479 	p->len = end_addr + 1;
480 	RTE_LOG(DEBUG, EAL, "PCI Port IO found start=0x%"PRIx64"\n", p->base);
481 	fclose(f);
482 
483 	return 0;
484 
485 error:
486 	fclose(f);
487 	return -1;
488 }
489 #endif
490 
491 void
492 pci_uio_ioport_read(struct rte_pci_ioport *p,
493 		    void *data, size_t len, off_t offset)
494 {
495 	uint8_t *d;
496 	int size;
497 	uintptr_t reg = p->base + offset;
498 
499 	for (d = data; len > 0; d += size, reg += size, len -= size) {
500 		if (len >= 4) {
501 			size = 4;
502 #if defined(RTE_ARCH_X86)
503 			*(uint32_t *)d = inl(reg);
504 #else
505 			*(uint32_t *)d = *(volatile uint32_t *)reg;
506 #endif
507 		} else if (len >= 2) {
508 			size = 2;
509 #if defined(RTE_ARCH_X86)
510 			*(uint16_t *)d = inw(reg);
511 #else
512 			*(uint16_t *)d = *(volatile uint16_t *)reg;
513 #endif
514 		} else {
515 			size = 1;
516 #if defined(RTE_ARCH_X86)
517 			*d = inb(reg);
518 #else
519 			*d = *(volatile uint8_t *)reg;
520 #endif
521 		}
522 	}
523 }
524 
525 void
526 pci_uio_ioport_write(struct rte_pci_ioport *p,
527 		     const void *data, size_t len, off_t offset)
528 {
529 	const uint8_t *s;
530 	int size;
531 	uintptr_t reg = p->base + offset;
532 
533 	for (s = data; len > 0; s += size, reg += size, len -= size) {
534 		if (len >= 4) {
535 			size = 4;
536 #if defined(RTE_ARCH_X86)
537 			outl_p(*(const uint32_t *)s, reg);
538 #else
539 			*(volatile uint32_t *)reg = *(const uint32_t *)s;
540 #endif
541 		} else if (len >= 2) {
542 			size = 2;
543 #if defined(RTE_ARCH_X86)
544 			outw_p(*(const uint16_t *)s, reg);
545 #else
546 			*(volatile uint16_t *)reg = *(const uint16_t *)s;
547 #endif
548 		} else {
549 			size = 1;
550 #if defined(RTE_ARCH_X86)
551 			outb_p(*s, reg);
552 #else
553 			*(volatile uint8_t *)reg = *s;
554 #endif
555 		}
556 	}
557 }
558 
559 int
560 pci_uio_ioport_unmap(struct rte_pci_ioport *p)
561 {
562 #if defined(RTE_ARCH_X86)
563 	RTE_SET_USED(p);
564 	/* FIXME close intr fd ? */
565 	return 0;
566 #else
567 	return munmap((void *)(uintptr_t)p->base, p->len);
568 #endif
569 }
570