xref: /linux/drivers/pci/pci-sysfs.c (revision 776cfebb430c7b22c208b1b17add97f354d97cab)
1 /*
2  * drivers/pci/pci-sysfs.c
3  *
4  * (C) Copyright 2002-2004 Greg Kroah-Hartman <greg@kroah.com>
5  * (C) Copyright 2002-2004 IBM Corp.
6  * (C) Copyright 2003 Matthew Wilcox
7  * (C) Copyright 2003 Hewlett-Packard
8  * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
9  * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
10  *
11  * File attributes for PCI devices
12  *
13  * Modeled after usb's driverfs.c
14  *
15  */
16 
17 
18 #include <linux/config.h>
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/stat.h>
22 #include <linux/topology.h>
23 #include <linux/mm.h>
24 
25 #include "pci.h"
26 
27 static int sysfs_initialized;	/* = 0 */
28 
29 /* show configuration fields */
30 #define pci_config_attr(field, format_string)				\
31 static ssize_t								\
32 field##_show(struct device *dev, char *buf)				\
33 {									\
34 	struct pci_dev *pdev;						\
35 									\
36 	pdev = to_pci_dev (dev);					\
37 	return sprintf (buf, format_string, pdev->field);		\
38 }
39 
40 pci_config_attr(vendor, "0x%04x\n");
41 pci_config_attr(device, "0x%04x\n");
42 pci_config_attr(subsystem_vendor, "0x%04x\n");
43 pci_config_attr(subsystem_device, "0x%04x\n");
44 pci_config_attr(class, "0x%06x\n");
45 pci_config_attr(irq, "%u\n");
46 
47 static ssize_t local_cpus_show(struct device *dev, char *buf)
48 {
49 	cpumask_t mask = pcibus_to_cpumask(to_pci_dev(dev)->bus);
50 	int len = cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
51 	strcat(buf,"\n");
52 	return 1+len;
53 }
54 
55 /* show resources */
56 static ssize_t
57 resource_show(struct device * dev, char * buf)
58 {
59 	struct pci_dev * pci_dev = to_pci_dev(dev);
60 	char * str = buf;
61 	int i;
62 	int max = 7;
63 
64 	if (pci_dev->subordinate)
65 		max = DEVICE_COUNT_RESOURCE;
66 
67 	for (i = 0; i < max; i++) {
68 		str += sprintf(str,"0x%016lx 0x%016lx 0x%016lx\n",
69 			       pci_resource_start(pci_dev,i),
70 			       pci_resource_end(pci_dev,i),
71 			       pci_resource_flags(pci_dev,i));
72 	}
73 	return (str - buf);
74 }
75 
76 struct device_attribute pci_dev_attrs[] = {
77 	__ATTR_RO(resource),
78 	__ATTR_RO(vendor),
79 	__ATTR_RO(device),
80 	__ATTR_RO(subsystem_vendor),
81 	__ATTR_RO(subsystem_device),
82 	__ATTR_RO(class),
83 	__ATTR_RO(irq),
84 	__ATTR_RO(local_cpus),
85 	__ATTR_NULL,
86 };
87 
88 static ssize_t
89 pci_read_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
90 {
91 	struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
92 	unsigned int size = 64;
93 	loff_t init_off = off;
94 	u8 *data = (u8*) buf;
95 
96 	/* Several chips lock up trying to read undefined config space */
97 	if (capable(CAP_SYS_ADMIN)) {
98 		size = dev->cfg_size;
99 	} else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
100 		size = 128;
101 	}
102 
103 	if (off > size)
104 		return 0;
105 	if (off + count > size) {
106 		size -= off;
107 		count = size;
108 	} else {
109 		size = count;
110 	}
111 
112 	if ((off & 1) && size) {
113 		u8 val;
114 		pci_read_config_byte(dev, off, &val);
115 		data[off - init_off] = val;
116 		off++;
117 		size--;
118 	}
119 
120 	if ((off & 3) && size > 2) {
121 		u16 val;
122 		pci_read_config_word(dev, off, &val);
123 		data[off - init_off] = val & 0xff;
124 		data[off - init_off + 1] = (val >> 8) & 0xff;
125 		off += 2;
126 		size -= 2;
127 	}
128 
129 	while (size > 3) {
130 		u32 val;
131 		pci_read_config_dword(dev, off, &val);
132 		data[off - init_off] = val & 0xff;
133 		data[off - init_off + 1] = (val >> 8) & 0xff;
134 		data[off - init_off + 2] = (val >> 16) & 0xff;
135 		data[off - init_off + 3] = (val >> 24) & 0xff;
136 		off += 4;
137 		size -= 4;
138 	}
139 
140 	if (size >= 2) {
141 		u16 val;
142 		pci_read_config_word(dev, off, &val);
143 		data[off - init_off] = val & 0xff;
144 		data[off - init_off + 1] = (val >> 8) & 0xff;
145 		off += 2;
146 		size -= 2;
147 	}
148 
149 	if (size > 0) {
150 		u8 val;
151 		pci_read_config_byte(dev, off, &val);
152 		data[off - init_off] = val;
153 		off++;
154 		--size;
155 	}
156 
157 	return count;
158 }
159 
160 static ssize_t
161 pci_write_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
162 {
163 	struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
164 	unsigned int size = count;
165 	loff_t init_off = off;
166 	u8 *data = (u8*) buf;
167 
168 	if (off > dev->cfg_size)
169 		return 0;
170 	if (off + count > dev->cfg_size) {
171 		size = dev->cfg_size - off;
172 		count = size;
173 	}
174 
175 	if ((off & 1) && size) {
176 		pci_write_config_byte(dev, off, data[off - init_off]);
177 		off++;
178 		size--;
179 	}
180 
181 	if ((off & 3) && size > 2) {
182 		u16 val = data[off - init_off];
183 		val |= (u16) data[off - init_off + 1] << 8;
184                 pci_write_config_word(dev, off, val);
185                 off += 2;
186                 size -= 2;
187         }
188 
189 	while (size > 3) {
190 		u32 val = data[off - init_off];
191 		val |= (u32) data[off - init_off + 1] << 8;
192 		val |= (u32) data[off - init_off + 2] << 16;
193 		val |= (u32) data[off - init_off + 3] << 24;
194 		pci_write_config_dword(dev, off, val);
195 		off += 4;
196 		size -= 4;
197 	}
198 
199 	if (size >= 2) {
200 		u16 val = data[off - init_off];
201 		val |= (u16) data[off - init_off + 1] << 8;
202 		pci_write_config_word(dev, off, val);
203 		off += 2;
204 		size -= 2;
205 	}
206 
207 	if (size) {
208 		pci_write_config_byte(dev, off, data[off - init_off]);
209 		off++;
210 		--size;
211 	}
212 
213 	return count;
214 }
215 
216 #ifdef HAVE_PCI_LEGACY
217 /**
218  * pci_read_legacy_io - read byte(s) from legacy I/O port space
219  * @kobj: kobject corresponding to file to read from
220  * @buf: buffer to store results
221  * @off: offset into legacy I/O port space
222  * @count: number of bytes to read
223  *
224  * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific
225  * callback routine (pci_legacy_read).
226  */
227 ssize_t
228 pci_read_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
229 {
230         struct pci_bus *bus = to_pci_bus(container_of(kobj,
231                                                       struct class_device,
232 						      kobj));
233 
234         /* Only support 1, 2 or 4 byte accesses */
235         if (count != 1 && count != 2 && count != 4)
236                 return -EINVAL;
237 
238         return pci_legacy_read(bus, off, (u32 *)buf, count);
239 }
240 
241 /**
242  * pci_write_legacy_io - write byte(s) to legacy I/O port space
243  * @kobj: kobject corresponding to file to read from
244  * @buf: buffer containing value to be written
245  * @off: offset into legacy I/O port space
246  * @count: number of bytes to write
247  *
248  * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific
249  * callback routine (pci_legacy_write).
250  */
251 ssize_t
252 pci_write_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
253 {
254         struct pci_bus *bus = to_pci_bus(container_of(kobj,
255 						      struct class_device,
256 						      kobj));
257         /* Only support 1, 2 or 4 byte accesses */
258         if (count != 1 && count != 2 && count != 4)
259                 return -EINVAL;
260 
261         return pci_legacy_write(bus, off, *(u32 *)buf, count);
262 }
263 
264 /**
265  * pci_mmap_legacy_mem - map legacy PCI memory into user memory space
266  * @kobj: kobject corresponding to device to be mapped
267  * @attr: struct bin_attribute for this file
268  * @vma: struct vm_area_struct passed to mmap
269  *
270  * Uses an arch specific callback, pci_mmap_legacy_page_range, to mmap
271  * legacy memory space (first meg of bus space) into application virtual
272  * memory space.
273  */
274 int
275 pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr,
276                     struct vm_area_struct *vma)
277 {
278         struct pci_bus *bus = to_pci_bus(container_of(kobj,
279                                                       struct class_device,
280 						      kobj));
281 
282         return pci_mmap_legacy_page_range(bus, vma);
283 }
284 #endif /* HAVE_PCI_LEGACY */
285 
286 #ifdef HAVE_PCI_MMAP
287 /**
288  * pci_mmap_resource - map a PCI resource into user memory space
289  * @kobj: kobject for mapping
290  * @attr: struct bin_attribute for the file being mapped
291  * @vma: struct vm_area_struct passed into the mmap
292  *
293  * Use the regular PCI mapping routines to map a PCI resource into userspace.
294  * FIXME: write combining?  maybe automatic for prefetchable regions?
295  */
296 static int
297 pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
298 		  struct vm_area_struct *vma)
299 {
300 	struct pci_dev *pdev = to_pci_dev(container_of(kobj,
301 						       struct device, kobj));
302 	struct resource *res = (struct resource *)attr->private;
303 	enum pci_mmap_state mmap_type;
304 
305 	vma->vm_pgoff += res->start >> PAGE_SHIFT;
306 	mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
307 
308 	return pci_mmap_page_range(pdev, vma, mmap_type, 0);
309 }
310 
311 /**
312  * pci_create_resource_files - create resource files in sysfs for @dev
313  * @dev: dev in question
314  *
315  * Walk the resources in @dev creating files for each resource available.
316  */
317 static void
318 pci_create_resource_files(struct pci_dev *pdev)
319 {
320 	int i;
321 
322 	/* Expose the PCI resources from this device as files */
323 	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
324 		struct bin_attribute *res_attr;
325 
326 		/* skip empty resources */
327 		if (!pci_resource_len(pdev, i))
328 			continue;
329 
330 		res_attr = kmalloc(sizeof(*res_attr) + 10, GFP_ATOMIC);
331 		if (res_attr) {
332 			memset(res_attr, 0, sizeof(*res_attr) + 10);
333 			pdev->res_attr[i] = res_attr;
334 			/* Allocated above after the res_attr struct */
335 			res_attr->attr.name = (char *)(res_attr + 1);
336 			sprintf(res_attr->attr.name, "resource%d", i);
337 			res_attr->size = pci_resource_len(pdev, i);
338 			res_attr->attr.mode = S_IRUSR | S_IWUSR;
339 			res_attr->attr.owner = THIS_MODULE;
340 			res_attr->mmap = pci_mmap_resource;
341 			res_attr->private = &pdev->resource[i];
342 			sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
343 		}
344 	}
345 }
346 
347 /**
348  * pci_remove_resource_files - cleanup resource files
349  * @dev: dev to cleanup
350  *
351  * If we created resource files for @dev, remove them from sysfs and
352  * free their resources.
353  */
354 static void
355 pci_remove_resource_files(struct pci_dev *pdev)
356 {
357 	int i;
358 
359 	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
360 		struct bin_attribute *res_attr;
361 
362 		res_attr = pdev->res_attr[i];
363 		if (res_attr) {
364 			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
365 			kfree(res_attr);
366 		}
367 	}
368 }
369 #else /* !HAVE_PCI_MMAP */
370 static inline void pci_create_resource_files(struct pci_dev *dev) { return; }
371 static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
372 #endif /* HAVE_PCI_MMAP */
373 
374 /**
375  * pci_write_rom - used to enable access to the PCI ROM display
376  * @kobj: kernel object handle
377  * @buf: user input
378  * @off: file offset
379  * @count: number of byte in input
380  *
381  * writing anything except 0 enables it
382  */
383 static ssize_t
384 pci_write_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
385 {
386 	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
387 
388 	if ((off ==  0) && (*buf == '0') && (count == 2))
389 		pdev->rom_attr_enabled = 0;
390 	else
391 		pdev->rom_attr_enabled = 1;
392 
393 	return count;
394 }
395 
396 /**
397  * pci_read_rom - read a PCI ROM
398  * @kobj: kernel object handle
399  * @buf: where to put the data we read from the ROM
400  * @off: file offset
401  * @count: number of bytes to read
402  *
403  * Put @count bytes starting at @off into @buf from the ROM in the PCI
404  * device corresponding to @kobj.
405  */
406 static ssize_t
407 pci_read_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
408 {
409 	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
410 	void __iomem *rom;
411 	size_t size;
412 
413 	if (!pdev->rom_attr_enabled)
414 		return -EINVAL;
415 
416 	rom = pci_map_rom(pdev, &size);	/* size starts out as PCI window size */
417 	if (!rom)
418 		return 0;
419 
420 	if (off >= size)
421 		count = 0;
422 	else {
423 		if (off + count > size)
424 			count = size - off;
425 
426 		memcpy_fromio(buf, rom + off, count);
427 	}
428 	pci_unmap_rom(pdev, rom);
429 
430 	return count;
431 }
432 
433 static struct bin_attribute pci_config_attr = {
434 	.attr =	{
435 		.name = "config",
436 		.mode = S_IRUGO | S_IWUSR,
437 		.owner = THIS_MODULE,
438 	},
439 	.size = 256,
440 	.read = pci_read_config,
441 	.write = pci_write_config,
442 };
443 
444 static struct bin_attribute pcie_config_attr = {
445 	.attr =	{
446 		.name = "config",
447 		.mode = S_IRUGO | S_IWUSR,
448 		.owner = THIS_MODULE,
449 	},
450 	.size = 4096,
451 	.read = pci_read_config,
452 	.write = pci_write_config,
453 };
454 
455 int pci_create_sysfs_dev_files (struct pci_dev *pdev)
456 {
457 	if (!sysfs_initialized)
458 		return -EACCES;
459 
460 	if (pdev->cfg_size < 4096)
461 		sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr);
462 	else
463 		sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr);
464 
465 	pci_create_resource_files(pdev);
466 
467 	/* If the device has a ROM, try to expose it in sysfs. */
468 	if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
469 		struct bin_attribute *rom_attr;
470 
471 		rom_attr = kmalloc(sizeof(*rom_attr), GFP_ATOMIC);
472 		if (rom_attr) {
473 			memset(rom_attr, 0x00, sizeof(*rom_attr));
474 			pdev->rom_attr = rom_attr;
475 			rom_attr->size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
476 			rom_attr->attr.name = "rom";
477 			rom_attr->attr.mode = S_IRUSR;
478 			rom_attr->attr.owner = THIS_MODULE;
479 			rom_attr->read = pci_read_rom;
480 			rom_attr->write = pci_write_rom;
481 			sysfs_create_bin_file(&pdev->dev.kobj, rom_attr);
482 		}
483 	}
484 	/* add platform-specific attributes */
485 	pcibios_add_platform_entries(pdev);
486 
487 	return 0;
488 }
489 
490 /**
491  * pci_remove_sysfs_dev_files - cleanup PCI specific sysfs files
492  * @pdev: device whose entries we should free
493  *
494  * Cleanup when @pdev is removed from sysfs.
495  */
496 void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
497 {
498 	if (pdev->cfg_size < 4096)
499 		sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
500 	else
501 		sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
502 
503 	pci_remove_resource_files(pdev);
504 
505 	if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
506 		if (pdev->rom_attr) {
507 			sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
508 			kfree(pdev->rom_attr);
509 		}
510 	}
511 }
512 
513 static int __init pci_sysfs_init(void)
514 {
515 	struct pci_dev *pdev = NULL;
516 
517 	sysfs_initialized = 1;
518 	for_each_pci_dev(pdev)
519 		pci_create_sysfs_dev_files(pdev);
520 
521 	return 0;
522 }
523 
524 __initcall(pci_sysfs_init);
525