xref: /linux/drivers/pci/devres.c (revision 42b16d3ac371a2fac9b6f08fd75f23f34ba3955a)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/device.h>
3 #include <linux/pci.h>
4 #include "pci.h"
5 
6 /*
7  * On the state of PCI's devres implementation:
8  *
9  * The older devres API for PCI has two significant problems:
10  *
11  * 1. It is very strongly tied to the statically allocated mapping table in
12  *    struct pcim_iomap_devres below. This is mostly solved in the sense of the
13  *    pcim_ functions in this file providing things like ranged mapping by
14  *    bypassing this table, whereas the functions that were present in the old
15  *    API still enter the mapping addresses into the table for users of the old
16  *    API.
17  *
18  * 2. The region-request-functions in pci.c do become managed IF the device has
19  *    been enabled with pcim_enable_device() instead of pci_enable_device().
20  *    This resulted in the API becoming inconsistent: Some functions have an
21  *    obviously managed counter-part (e.g., pci_iomap() <-> pcim_iomap()),
22  *    whereas some don't and are never managed, while others don't and are
23  *    _sometimes_ managed (e.g. pci_request_region()).
24  *
25  *    Consequently, in the new API, region requests performed by the pcim_
26  *    functions are automatically cleaned up through the devres callback
27  *    pcim_addr_resource_release().
28  *
29  *    Users of pcim_enable_device() + pci_*region*() are redirected in
30  *    pci.c to the managed functions here in this file. This isn't exactly
31  *    perfect, but the only alternative way would be to port ALL drivers
32  *    using said combination to pcim_ functions.
33  *
34  * TODO:
35  * Remove the legacy table entirely once all calls to pcim_iomap_table() in
36  * the kernel have been removed.
37  */
38 
39 /*
40  * Legacy struct storing addresses to whole mapped BARs.
41  */
42 struct pcim_iomap_devres {
43 	void __iomem *table[PCI_STD_NUM_BARS];
44 };
45 
46 /* Used to restore the old INTx state on driver detach. */
47 struct pcim_intx_devres {
48 	int orig_intx;
49 };
50 
51 enum pcim_addr_devres_type {
52 	/* Default initializer. */
53 	PCIM_ADDR_DEVRES_TYPE_INVALID,
54 
55 	/* A requested region spanning an entire BAR. */
56 	PCIM_ADDR_DEVRES_TYPE_REGION,
57 
58 	/*
59 	 * A requested region spanning an entire BAR, and a mapping for
60 	 * the entire BAR.
61 	 */
62 	PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING,
63 
64 	/*
65 	 * A mapping within a BAR, either spanning the whole BAR or just a
66 	 * range.  Without a requested region.
67 	 */
68 	PCIM_ADDR_DEVRES_TYPE_MAPPING,
69 };
70 
71 /*
72  * This struct envelops IO or MEM addresses, i.e., mappings and region
73  * requests, because those are very frequently requested and released
74  * together.
75  */
76 struct pcim_addr_devres {
77 	enum pcim_addr_devres_type type;
78 	void __iomem *baseaddr;
79 	unsigned long offset;
80 	unsigned long len;
81 	int bar;
82 };
83 
pcim_addr_devres_clear(struct pcim_addr_devres * res)84 static inline void pcim_addr_devres_clear(struct pcim_addr_devres *res)
85 {
86 	memset(res, 0, sizeof(*res));
87 	res->bar = -1;
88 }
89 
90 /*
91  * The following functions, __pcim_*_region*, exist as counterparts to the
92  * versions from pci.c - which, unfortunately, can be in "hybrid mode", i.e.,
93  * sometimes managed, sometimes not.
94  *
95  * To separate the APIs cleanly, we define our own, simplified versions here.
96  */
97 
98 /**
99  * __pcim_request_region_range - Request a ranged region
100  * @pdev: PCI device the region belongs to
101  * @bar: BAR the range is within
102  * @offset: offset from the BAR's start address
103  * @maxlen: length in bytes, beginning at @offset
104  * @name: name associated with the request
105  * @req_flags: flags for the request, e.g., for kernel-exclusive requests
106  *
107  * Returns: 0 on success, a negative error code on failure.
108  *
109  * Request a range within a device's PCI BAR.  Sanity check the input.
110  */
__pcim_request_region_range(struct pci_dev * pdev,int bar,unsigned long offset,unsigned long maxlen,const char * name,int req_flags)111 static int __pcim_request_region_range(struct pci_dev *pdev, int bar,
112 				       unsigned long offset,
113 				       unsigned long maxlen,
114 				       const char *name, int req_flags)
115 {
116 	resource_size_t start = pci_resource_start(pdev, bar);
117 	resource_size_t len = pci_resource_len(pdev, bar);
118 	unsigned long dev_flags = pci_resource_flags(pdev, bar);
119 
120 	if (start == 0 || len == 0) /* Unused BAR. */
121 		return 0;
122 	if (len <= offset)
123 		return -EINVAL;
124 
125 	start += offset;
126 	len -= offset;
127 
128 	if (len > maxlen && maxlen != 0)
129 		len = maxlen;
130 
131 	if (dev_flags & IORESOURCE_IO) {
132 		if (!request_region(start, len, name))
133 			return -EBUSY;
134 	} else if (dev_flags & IORESOURCE_MEM) {
135 		if (!__request_mem_region(start, len, name, req_flags))
136 			return -EBUSY;
137 	} else {
138 		/* That's not a device we can request anything on. */
139 		return -ENODEV;
140 	}
141 
142 	return 0;
143 }
144 
__pcim_release_region_range(struct pci_dev * pdev,int bar,unsigned long offset,unsigned long maxlen)145 static void __pcim_release_region_range(struct pci_dev *pdev, int bar,
146 					unsigned long offset,
147 					unsigned long maxlen)
148 {
149 	resource_size_t start = pci_resource_start(pdev, bar);
150 	resource_size_t len = pci_resource_len(pdev, bar);
151 	unsigned long flags = pci_resource_flags(pdev, bar);
152 
153 	if (len <= offset || start == 0)
154 		return;
155 
156 	if (len == 0 || maxlen == 0) /* This an unused BAR. Do nothing. */
157 		return;
158 
159 	start += offset;
160 	len -= offset;
161 
162 	if (len > maxlen)
163 		len = maxlen;
164 
165 	if (flags & IORESOURCE_IO)
166 		release_region(start, len);
167 	else if (flags & IORESOURCE_MEM)
168 		release_mem_region(start, len);
169 }
170 
__pcim_request_region(struct pci_dev * pdev,int bar,const char * name,int flags)171 static int __pcim_request_region(struct pci_dev *pdev, int bar,
172 				 const char *name, int flags)
173 {
174 	unsigned long offset = 0;
175 	unsigned long len = pci_resource_len(pdev, bar);
176 
177 	return __pcim_request_region_range(pdev, bar, offset, len, name, flags);
178 }
179 
__pcim_release_region(struct pci_dev * pdev,int bar)180 static void __pcim_release_region(struct pci_dev *pdev, int bar)
181 {
182 	unsigned long offset = 0;
183 	unsigned long len = pci_resource_len(pdev, bar);
184 
185 	__pcim_release_region_range(pdev, bar, offset, len);
186 }
187 
pcim_addr_resource_release(struct device * dev,void * resource_raw)188 static void pcim_addr_resource_release(struct device *dev, void *resource_raw)
189 {
190 	struct pci_dev *pdev = to_pci_dev(dev);
191 	struct pcim_addr_devres *res = resource_raw;
192 
193 	switch (res->type) {
194 	case PCIM_ADDR_DEVRES_TYPE_REGION:
195 		__pcim_release_region(pdev, res->bar);
196 		break;
197 	case PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING:
198 		pci_iounmap(pdev, res->baseaddr);
199 		__pcim_release_region(pdev, res->bar);
200 		break;
201 	case PCIM_ADDR_DEVRES_TYPE_MAPPING:
202 		pci_iounmap(pdev, res->baseaddr);
203 		break;
204 	default:
205 		break;
206 	}
207 }
208 
pcim_addr_devres_alloc(struct pci_dev * pdev)209 static struct pcim_addr_devres *pcim_addr_devres_alloc(struct pci_dev *pdev)
210 {
211 	struct pcim_addr_devres *res;
212 
213 	res = devres_alloc_node(pcim_addr_resource_release, sizeof(*res),
214 				GFP_KERNEL, dev_to_node(&pdev->dev));
215 	if (res)
216 		pcim_addr_devres_clear(res);
217 	return res;
218 }
219 
220 /* Just for consistency and readability. */
pcim_addr_devres_free(struct pcim_addr_devres * res)221 static inline void pcim_addr_devres_free(struct pcim_addr_devres *res)
222 {
223 	devres_free(res);
224 }
225 
226 /*
227  * Used by devres to identify a pcim_addr_devres.
228  */
pcim_addr_resources_match(struct device * dev,void * a_raw,void * b_raw)229 static int pcim_addr_resources_match(struct device *dev,
230 				     void *a_raw, void *b_raw)
231 {
232 	struct pcim_addr_devres *a, *b;
233 
234 	a = a_raw;
235 	b = b_raw;
236 
237 	if (a->type != b->type)
238 		return 0;
239 
240 	switch (a->type) {
241 	case PCIM_ADDR_DEVRES_TYPE_REGION:
242 	case PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING:
243 		return a->bar == b->bar;
244 	case PCIM_ADDR_DEVRES_TYPE_MAPPING:
245 		return a->baseaddr == b->baseaddr;
246 	default:
247 		return 0;
248 	}
249 }
250 
devm_pci_unmap_iospace(struct device * dev,void * ptr)251 static void devm_pci_unmap_iospace(struct device *dev, void *ptr)
252 {
253 	struct resource **res = ptr;
254 
255 	pci_unmap_iospace(*res);
256 }
257 
258 /**
259  * devm_pci_remap_iospace - Managed pci_remap_iospace()
260  * @dev: Generic device to remap IO address for
261  * @res: Resource describing the I/O space
262  * @phys_addr: physical address of range to be mapped
263  *
264  * Managed pci_remap_iospace().  Map is automatically unmapped on driver
265  * detach.
266  */
devm_pci_remap_iospace(struct device * dev,const struct resource * res,phys_addr_t phys_addr)267 int devm_pci_remap_iospace(struct device *dev, const struct resource *res,
268 			   phys_addr_t phys_addr)
269 {
270 	const struct resource **ptr;
271 	int error;
272 
273 	ptr = devres_alloc(devm_pci_unmap_iospace, sizeof(*ptr), GFP_KERNEL);
274 	if (!ptr)
275 		return -ENOMEM;
276 
277 	error = pci_remap_iospace(res, phys_addr);
278 	if (error) {
279 		devres_free(ptr);
280 	} else	{
281 		*ptr = res;
282 		devres_add(dev, ptr);
283 	}
284 
285 	return error;
286 }
287 EXPORT_SYMBOL(devm_pci_remap_iospace);
288 
289 /**
290  * devm_pci_remap_cfgspace - Managed pci_remap_cfgspace()
291  * @dev: Generic device to remap IO address for
292  * @offset: Resource address to map
293  * @size: Size of map
294  *
295  * Managed pci_remap_cfgspace().  Map is automatically unmapped on driver
296  * detach.
297  */
devm_pci_remap_cfgspace(struct device * dev,resource_size_t offset,resource_size_t size)298 void __iomem *devm_pci_remap_cfgspace(struct device *dev,
299 				      resource_size_t offset,
300 				      resource_size_t size)
301 {
302 	void __iomem **ptr, *addr;
303 
304 	ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
305 	if (!ptr)
306 		return NULL;
307 
308 	addr = pci_remap_cfgspace(offset, size);
309 	if (addr) {
310 		*ptr = addr;
311 		devres_add(dev, ptr);
312 	} else
313 		devres_free(ptr);
314 
315 	return addr;
316 }
317 EXPORT_SYMBOL(devm_pci_remap_cfgspace);
318 
319 /**
320  * devm_pci_remap_cfg_resource - check, request region and ioremap cfg resource
321  * @dev: generic device to handle the resource for
322  * @res: configuration space resource to be handled
323  *
324  * Checks that a resource is a valid memory region, requests the memory
325  * region and ioremaps with pci_remap_cfgspace() API that ensures the
326  * proper PCI configuration space memory attributes are guaranteed.
327  *
328  * All operations are managed and will be undone on driver detach.
329  *
330  * Returns a pointer to the remapped memory or an IOMEM_ERR_PTR() encoded error
331  * code on failure. Usage example::
332  *
333  *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
334  *	base = devm_pci_remap_cfg_resource(&pdev->dev, res);
335  *	if (IS_ERR(base))
336  *		return PTR_ERR(base);
337  */
devm_pci_remap_cfg_resource(struct device * dev,struct resource * res)338 void __iomem *devm_pci_remap_cfg_resource(struct device *dev,
339 					  struct resource *res)
340 {
341 	resource_size_t size;
342 	const char *name;
343 	void __iomem *dest_ptr;
344 
345 	BUG_ON(!dev);
346 
347 	if (!res || resource_type(res) != IORESOURCE_MEM) {
348 		dev_err(dev, "invalid resource\n");
349 		return IOMEM_ERR_PTR(-EINVAL);
350 	}
351 
352 	size = resource_size(res);
353 
354 	if (res->name)
355 		name = devm_kasprintf(dev, GFP_KERNEL, "%s %s", dev_name(dev),
356 				      res->name);
357 	else
358 		name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
359 	if (!name)
360 		return IOMEM_ERR_PTR(-ENOMEM);
361 
362 	if (!devm_request_mem_region(dev, res->start, size, name)) {
363 		dev_err(dev, "can't request region for resource %pR\n", res);
364 		return IOMEM_ERR_PTR(-EBUSY);
365 	}
366 
367 	dest_ptr = devm_pci_remap_cfgspace(dev, res->start, size);
368 	if (!dest_ptr) {
369 		dev_err(dev, "ioremap failed for resource %pR\n", res);
370 		devm_release_mem_region(dev, res->start, size);
371 		dest_ptr = IOMEM_ERR_PTR(-ENOMEM);
372 	}
373 
374 	return dest_ptr;
375 }
376 EXPORT_SYMBOL(devm_pci_remap_cfg_resource);
377 
__pcim_clear_mwi(void * pdev_raw)378 static void __pcim_clear_mwi(void *pdev_raw)
379 {
380 	struct pci_dev *pdev = pdev_raw;
381 
382 	pci_clear_mwi(pdev);
383 }
384 
385 /**
386  * pcim_set_mwi - a device-managed pci_set_mwi()
387  * @pdev: the PCI device for which MWI is enabled
388  *
389  * Managed pci_set_mwi().
390  *
391  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
392  */
pcim_set_mwi(struct pci_dev * pdev)393 int pcim_set_mwi(struct pci_dev *pdev)
394 {
395 	int ret;
396 
397 	ret = devm_add_action(&pdev->dev, __pcim_clear_mwi, pdev);
398 	if (ret != 0)
399 		return ret;
400 
401 	ret = pci_set_mwi(pdev);
402 	if (ret != 0)
403 		devm_remove_action(&pdev->dev, __pcim_clear_mwi, pdev);
404 
405 	return ret;
406 }
407 EXPORT_SYMBOL(pcim_set_mwi);
408 
mask_contains_bar(int mask,int bar)409 static inline bool mask_contains_bar(int mask, int bar)
410 {
411 	return mask & BIT(bar);
412 }
413 
414 /*
415  * This is a copy of pci_intx() used to bypass the problem of recursive
416  * function calls due to the hybrid nature of pci_intx().
417  */
__pcim_intx(struct pci_dev * pdev,int enable)418 static void __pcim_intx(struct pci_dev *pdev, int enable)
419 {
420 	u16 pci_command, new;
421 
422 	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
423 
424 	if (enable)
425 		new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
426 	else
427 		new = pci_command | PCI_COMMAND_INTX_DISABLE;
428 
429 	if (new != pci_command)
430 		pci_write_config_word(pdev, PCI_COMMAND, new);
431 }
432 
pcim_intx_restore(struct device * dev,void * data)433 static void pcim_intx_restore(struct device *dev, void *data)
434 {
435 	struct pci_dev *pdev = to_pci_dev(dev);
436 	struct pcim_intx_devres *res = data;
437 
438 	__pcim_intx(pdev, res->orig_intx);
439 }
440 
get_or_create_intx_devres(struct device * dev)441 static struct pcim_intx_devres *get_or_create_intx_devres(struct device *dev)
442 {
443 	struct pcim_intx_devres *res;
444 
445 	res = devres_find(dev, pcim_intx_restore, NULL, NULL);
446 	if (res)
447 		return res;
448 
449 	res = devres_alloc(pcim_intx_restore, sizeof(*res), GFP_KERNEL);
450 	if (res)
451 		devres_add(dev, res);
452 
453 	return res;
454 }
455 
456 /**
457  * pcim_intx - managed pci_intx()
458  * @pdev: the PCI device to operate on
459  * @enable: boolean: whether to enable or disable PCI INTx
460  *
461  * Returns: 0 on success, -ENOMEM on error.
462  *
463  * Enable/disable PCI INTx for device @pdev.
464  * Restore the original state on driver detach.
465  */
pcim_intx(struct pci_dev * pdev,int enable)466 int pcim_intx(struct pci_dev *pdev, int enable)
467 {
468 	struct pcim_intx_devres *res;
469 
470 	res = get_or_create_intx_devres(&pdev->dev);
471 	if (!res)
472 		return -ENOMEM;
473 
474 	res->orig_intx = !enable;
475 	__pcim_intx(pdev, enable);
476 
477 	return 0;
478 }
479 
pcim_disable_device(void * pdev_raw)480 static void pcim_disable_device(void *pdev_raw)
481 {
482 	struct pci_dev *pdev = pdev_raw;
483 
484 	if (!pdev->pinned)
485 		pci_disable_device(pdev);
486 
487 	pdev->is_managed = false;
488 }
489 
490 /**
491  * pcim_enable_device - Managed pci_enable_device()
492  * @pdev: PCI device to be initialized
493  *
494  * Returns: 0 on success, negative error code on failure.
495  *
496  * Managed pci_enable_device(). Device will automatically be disabled on
497  * driver detach.
498  */
pcim_enable_device(struct pci_dev * pdev)499 int pcim_enable_device(struct pci_dev *pdev)
500 {
501 	int ret;
502 
503 	ret = devm_add_action(&pdev->dev, pcim_disable_device, pdev);
504 	if (ret != 0)
505 		return ret;
506 
507 	/*
508 	 * We prefer removing the action in case of an error over
509 	 * devm_add_action_or_reset() because the latter could theoretically be
510 	 * disturbed by users having pinned the device too soon.
511 	 */
512 	ret = pci_enable_device(pdev);
513 	if (ret != 0) {
514 		devm_remove_action(&pdev->dev, pcim_disable_device, pdev);
515 		return ret;
516 	}
517 
518 	pdev->is_managed = true;
519 
520 	return ret;
521 }
522 EXPORT_SYMBOL(pcim_enable_device);
523 
524 /**
525  * pcim_pin_device - Pin managed PCI device
526  * @pdev: PCI device to pin
527  *
528  * Pin managed PCI device @pdev. Pinned device won't be disabled on driver
529  * detach. @pdev must have been enabled with pcim_enable_device().
530  */
pcim_pin_device(struct pci_dev * pdev)531 void pcim_pin_device(struct pci_dev *pdev)
532 {
533 	pdev->pinned = true;
534 }
535 EXPORT_SYMBOL(pcim_pin_device);
536 
pcim_iomap_release(struct device * gendev,void * res)537 static void pcim_iomap_release(struct device *gendev, void *res)
538 {
539 	/*
540 	 * Do nothing. This is legacy code.
541 	 *
542 	 * Cleanup of the mappings is now done directly through the callbacks
543 	 * registered when creating them.
544 	 */
545 }
546 
547 /**
548  * pcim_iomap_table - access iomap allocation table (DEPRECATED)
549  * @pdev: PCI device to access iomap table for
550  *
551  * Returns:
552  * Const pointer to array of __iomem pointers on success, NULL on failure.
553  *
554  * Access iomap allocation table for @dev.  If iomap table doesn't
555  * exist and @pdev is managed, it will be allocated.  All iomaps
556  * recorded in the iomap table are automatically unmapped on driver
557  * detach.
558  *
559  * This function might sleep when the table is first allocated but can
560  * be safely called without context and guaranteed to succeed once
561  * allocated.
562  *
563  * This function is DEPRECATED. Do not use it in new code. Instead, obtain a
564  * mapping's address directly from one of the pcim_* mapping functions. For
565  * example:
566  * void __iomem \*mappy = pcim_iomap(pdev, bar, length);
567  */
pcim_iomap_table(struct pci_dev * pdev)568 void __iomem * const *pcim_iomap_table(struct pci_dev *pdev)
569 {
570 	struct pcim_iomap_devres *dr, *new_dr;
571 
572 	dr = devres_find(&pdev->dev, pcim_iomap_release, NULL, NULL);
573 	if (dr)
574 		return dr->table;
575 
576 	new_dr = devres_alloc_node(pcim_iomap_release, sizeof(*new_dr), GFP_KERNEL,
577 				   dev_to_node(&pdev->dev));
578 	if (!new_dr)
579 		return NULL;
580 	dr = devres_get(&pdev->dev, new_dr, NULL, NULL);
581 	return dr->table;
582 }
583 EXPORT_SYMBOL(pcim_iomap_table);
584 
585 /*
586  * Fill the legacy mapping-table, so that drivers using the old API can
587  * still get a BAR's mapping address through pcim_iomap_table().
588  */
pcim_add_mapping_to_legacy_table(struct pci_dev * pdev,void __iomem * mapping,int bar)589 static int pcim_add_mapping_to_legacy_table(struct pci_dev *pdev,
590 					    void __iomem *mapping, int bar)
591 {
592 	void __iomem **legacy_iomap_table;
593 
594 	if (bar >= PCI_STD_NUM_BARS)
595 		return -EINVAL;
596 
597 	legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev);
598 	if (!legacy_iomap_table)
599 		return -ENOMEM;
600 
601 	/* The legacy mechanism doesn't allow for duplicate mappings. */
602 	WARN_ON(legacy_iomap_table[bar]);
603 
604 	legacy_iomap_table[bar] = mapping;
605 
606 	return 0;
607 }
608 
609 /*
610  * Remove a mapping. The table only contains whole-BAR mappings, so this will
611  * never interfere with ranged mappings.
612  */
pcim_remove_mapping_from_legacy_table(struct pci_dev * pdev,void __iomem * addr)613 static void pcim_remove_mapping_from_legacy_table(struct pci_dev *pdev,
614 						  void __iomem *addr)
615 {
616 	int bar;
617 	void __iomem **legacy_iomap_table;
618 
619 	legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev);
620 	if (!legacy_iomap_table)
621 		return;
622 
623 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
624 		if (legacy_iomap_table[bar] == addr) {
625 			legacy_iomap_table[bar] = NULL;
626 			return;
627 		}
628 	}
629 }
630 
631 /*
632  * The same as pcim_remove_mapping_from_legacy_table(), but identifies the
633  * mapping by its BAR index.
634  */
pcim_remove_bar_from_legacy_table(struct pci_dev * pdev,int bar)635 static void pcim_remove_bar_from_legacy_table(struct pci_dev *pdev, int bar)
636 {
637 	void __iomem **legacy_iomap_table;
638 
639 	if (bar >= PCI_STD_NUM_BARS)
640 		return;
641 
642 	legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev);
643 	if (!legacy_iomap_table)
644 		return;
645 
646 	legacy_iomap_table[bar] = NULL;
647 }
648 
649 /**
650  * pcim_iomap - Managed pcim_iomap()
651  * @pdev: PCI device to iomap for
652  * @bar: BAR to iomap
653  * @maxlen: Maximum length of iomap
654  *
655  * Returns: __iomem pointer on success, NULL on failure.
656  *
657  * Managed pci_iomap(). Map is automatically unmapped on driver detach. If
658  * desired, unmap manually only with pcim_iounmap().
659  *
660  * This SHOULD only be used once per BAR.
661  *
662  * NOTE:
663  * Contrary to the other pcim_* functions, this function does not return an
664  * IOMEM_ERR_PTR() on failure, but a simple NULL. This is done for backwards
665  * compatibility.
666  */
pcim_iomap(struct pci_dev * pdev,int bar,unsigned long maxlen)667 void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen)
668 {
669 	void __iomem *mapping;
670 	struct pcim_addr_devres *res;
671 
672 	res = pcim_addr_devres_alloc(pdev);
673 	if (!res)
674 		return NULL;
675 	res->type = PCIM_ADDR_DEVRES_TYPE_MAPPING;
676 
677 	mapping = pci_iomap(pdev, bar, maxlen);
678 	if (!mapping)
679 		goto err_iomap;
680 	res->baseaddr = mapping;
681 
682 	if (pcim_add_mapping_to_legacy_table(pdev, mapping, bar) != 0)
683 		goto err_table;
684 
685 	devres_add(&pdev->dev, res);
686 	return mapping;
687 
688 err_table:
689 	pci_iounmap(pdev, mapping);
690 err_iomap:
691 	pcim_addr_devres_free(res);
692 	return NULL;
693 }
694 EXPORT_SYMBOL(pcim_iomap);
695 
696 /**
697  * pcim_iounmap - Managed pci_iounmap()
698  * @pdev: PCI device to iounmap for
699  * @addr: Address to unmap
700  *
701  * Managed pci_iounmap(). @addr must have been mapped using a pcim_* mapping
702  * function.
703  */
pcim_iounmap(struct pci_dev * pdev,void __iomem * addr)704 void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr)
705 {
706 	struct pcim_addr_devres res_searched;
707 
708 	pcim_addr_devres_clear(&res_searched);
709 	res_searched.type = PCIM_ADDR_DEVRES_TYPE_MAPPING;
710 	res_searched.baseaddr = addr;
711 
712 	if (devres_release(&pdev->dev, pcim_addr_resource_release,
713 			pcim_addr_resources_match, &res_searched) != 0) {
714 		/* Doesn't exist. User passed nonsense. */
715 		return;
716 	}
717 
718 	pcim_remove_mapping_from_legacy_table(pdev, addr);
719 }
720 EXPORT_SYMBOL(pcim_iounmap);
721 
722 /**
723  * pcim_iomap_region - Request and iomap a PCI BAR
724  * @pdev: PCI device to map IO resources for
725  * @bar: Index of a BAR to map
726  * @name: Name associated with the request
727  *
728  * Returns: __iomem pointer on success, an IOMEM_ERR_PTR on failure.
729  *
730  * Mapping and region will get automatically released on driver detach. If
731  * desired, release manually only with pcim_iounmap_region().
732  */
pcim_iomap_region(struct pci_dev * pdev,int bar,const char * name)733 void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
734 				       const char *name)
735 {
736 	int ret;
737 	struct pcim_addr_devres *res;
738 
739 	res = pcim_addr_devres_alloc(pdev);
740 	if (!res)
741 		return IOMEM_ERR_PTR(-ENOMEM);
742 
743 	res->type = PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING;
744 	res->bar = bar;
745 
746 	ret = __pcim_request_region(pdev, bar, name, 0);
747 	if (ret != 0)
748 		goto err_region;
749 
750 	res->baseaddr = pci_iomap(pdev, bar, 0);
751 	if (!res->baseaddr) {
752 		ret = -EINVAL;
753 		goto err_iomap;
754 	}
755 
756 	devres_add(&pdev->dev, res);
757 	return res->baseaddr;
758 
759 err_iomap:
760 	__pcim_release_region(pdev, bar);
761 err_region:
762 	pcim_addr_devres_free(res);
763 
764 	return IOMEM_ERR_PTR(ret);
765 }
766 EXPORT_SYMBOL(pcim_iomap_region);
767 
768 /**
769  * pcim_iounmap_region - Unmap and release a PCI BAR
770  * @pdev: PCI device to operate on
771  * @bar: Index of BAR to unmap and release
772  *
773  * Unmap a BAR and release its region manually. Only pass BARs that were
774  * previously mapped by pcim_iomap_region().
775  */
pcim_iounmap_region(struct pci_dev * pdev,int bar)776 static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
777 {
778 	struct pcim_addr_devres res_searched;
779 
780 	pcim_addr_devres_clear(&res_searched);
781 	res_searched.type = PCIM_ADDR_DEVRES_TYPE_REGION_MAPPING;
782 	res_searched.bar = bar;
783 
784 	devres_release(&pdev->dev, pcim_addr_resource_release,
785 			pcim_addr_resources_match, &res_searched);
786 }
787 
788 /**
789  * pcim_iomap_regions - Request and iomap PCI BARs (DEPRECATED)
790  * @pdev: PCI device to map IO resources for
791  * @mask: Mask of BARs to request and iomap
792  * @name: Name associated with the requests
793  *
794  * Returns: 0 on success, negative error code on failure.
795  *
796  * Request and iomap regions specified by @mask.
797  *
798  * This function is DEPRECATED. Do not use it in new code.
799  * Use pcim_iomap_region() instead.
800  */
pcim_iomap_regions(struct pci_dev * pdev,int mask,const char * name)801 int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
802 {
803 	int ret;
804 	int bar;
805 	void __iomem *mapping;
806 
807 	for (bar = 0; bar < DEVICE_COUNT_RESOURCE; bar++) {
808 		if (!mask_contains_bar(mask, bar))
809 			continue;
810 
811 		mapping = pcim_iomap_region(pdev, bar, name);
812 		if (IS_ERR(mapping)) {
813 			ret = PTR_ERR(mapping);
814 			goto err;
815 		}
816 		ret = pcim_add_mapping_to_legacy_table(pdev, mapping, bar);
817 		if (ret != 0)
818 			goto err;
819 	}
820 
821 	return 0;
822 
823 err:
824 	while (--bar >= 0) {
825 		pcim_iounmap_region(pdev, bar);
826 		pcim_remove_bar_from_legacy_table(pdev, bar);
827 	}
828 
829 	return ret;
830 }
831 EXPORT_SYMBOL(pcim_iomap_regions);
832 
_pcim_request_region(struct pci_dev * pdev,int bar,const char * name,int request_flags)833 static int _pcim_request_region(struct pci_dev *pdev, int bar, const char *name,
834 				int request_flags)
835 {
836 	int ret;
837 	struct pcim_addr_devres *res;
838 
839 	res = pcim_addr_devres_alloc(pdev);
840 	if (!res)
841 		return -ENOMEM;
842 	res->type = PCIM_ADDR_DEVRES_TYPE_REGION;
843 	res->bar = bar;
844 
845 	ret = __pcim_request_region(pdev, bar, name, request_flags);
846 	if (ret != 0) {
847 		pcim_addr_devres_free(res);
848 		return ret;
849 	}
850 
851 	devres_add(&pdev->dev, res);
852 	return 0;
853 }
854 
855 /**
856  * pcim_request_region - Request a PCI BAR
857  * @pdev: PCI device to requestion region for
858  * @bar: Index of BAR to request
859  * @name: Name associated with the request
860  *
861  * Returns: 0 on success, a negative error code on failure.
862  *
863  * Request region specified by @bar.
864  *
865  * The region will automatically be released on driver detach. If desired,
866  * release manually only with pcim_release_region().
867  */
pcim_request_region(struct pci_dev * pdev,int bar,const char * name)868 int pcim_request_region(struct pci_dev *pdev, int bar, const char *name)
869 {
870 	return _pcim_request_region(pdev, bar, name, 0);
871 }
872 EXPORT_SYMBOL(pcim_request_region);
873 
874 /**
875  * pcim_request_region_exclusive - Request a PCI BAR exclusively
876  * @pdev: PCI device to requestion region for
877  * @bar: Index of BAR to request
878  * @name: Name associated with the request
879  *
880  * Returns: 0 on success, a negative error code on failure.
881  *
882  * Request region specified by @bar exclusively.
883  *
884  * The region will automatically be released on driver detach. If desired,
885  * release manually only with pcim_release_region().
886  */
pcim_request_region_exclusive(struct pci_dev * pdev,int bar,const char * name)887 int pcim_request_region_exclusive(struct pci_dev *pdev, int bar, const char *name)
888 {
889 	return _pcim_request_region(pdev, bar, name, IORESOURCE_EXCLUSIVE);
890 }
891 
892 /**
893  * pcim_release_region - Release a PCI BAR
894  * @pdev: PCI device to operate on
895  * @bar: Index of BAR to release
896  *
897  * Release a region manually that was previously requested by
898  * pcim_request_region().
899  */
pcim_release_region(struct pci_dev * pdev,int bar)900 void pcim_release_region(struct pci_dev *pdev, int bar)
901 {
902 	struct pcim_addr_devres res_searched;
903 
904 	pcim_addr_devres_clear(&res_searched);
905 	res_searched.type = PCIM_ADDR_DEVRES_TYPE_REGION;
906 	res_searched.bar = bar;
907 
908 	devres_release(&pdev->dev, pcim_addr_resource_release,
909 			pcim_addr_resources_match, &res_searched);
910 }
911 
912 
913 /**
914  * pcim_release_all_regions - Release all regions of a PCI-device
915  * @pdev: the PCI device
916  *
917  * Release all regions previously requested through pcim_request_region()
918  * or pcim_request_all_regions().
919  *
920  * Can be called from any context, i.e., not necessarily as a counterpart to
921  * pcim_request_all_regions().
922  */
pcim_release_all_regions(struct pci_dev * pdev)923 static void pcim_release_all_regions(struct pci_dev *pdev)
924 {
925 	int bar;
926 
927 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++)
928 		pcim_release_region(pdev, bar);
929 }
930 
931 /**
932  * pcim_request_all_regions - Request all regions
933  * @pdev: PCI device to map IO resources for
934  * @name: name associated with the request
935  *
936  * Returns: 0 on success, negative error code on failure.
937  *
938  * Requested regions will automatically be released at driver detach. If
939  * desired, release individual regions with pcim_release_region() or all of
940  * them at once with pcim_release_all_regions().
941  */
pcim_request_all_regions(struct pci_dev * pdev,const char * name)942 static int pcim_request_all_regions(struct pci_dev *pdev, const char *name)
943 {
944 	int ret;
945 	int bar;
946 
947 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
948 		ret = pcim_request_region(pdev, bar, name);
949 		if (ret != 0)
950 			goto err;
951 	}
952 
953 	return 0;
954 
955 err:
956 	pcim_release_all_regions(pdev);
957 
958 	return ret;
959 }
960 
961 /**
962  * pcim_iomap_regions_request_all - Request all BARs and iomap specified ones
963  *			(DEPRECATED)
964  * @pdev: PCI device to map IO resources for
965  * @mask: Mask of BARs to iomap
966  * @name: Name associated with the requests
967  *
968  * Returns: 0 on success, negative error code on failure.
969  *
970  * Request all PCI BARs and iomap regions specified by @mask.
971  *
972  * To release these resources manually, call pcim_release_region() for the
973  * regions and pcim_iounmap() for the mappings.
974  *
975  * This function is DEPRECATED. Don't use it in new code. Instead, use one
976  * of the pcim_* region request functions in combination with a pcim_*
977  * mapping function.
978  */
pcim_iomap_regions_request_all(struct pci_dev * pdev,int mask,const char * name)979 int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
980 				   const char *name)
981 {
982 	int bar;
983 	int ret;
984 	void __iomem **legacy_iomap_table;
985 
986 	ret = pcim_request_all_regions(pdev, name);
987 	if (ret != 0)
988 		return ret;
989 
990 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
991 		if (!mask_contains_bar(mask, bar))
992 			continue;
993 		if (!pcim_iomap(pdev, bar, 0))
994 			goto err;
995 	}
996 
997 	return 0;
998 
999 err:
1000 	/*
1001 	 * If bar is larger than 0, then pcim_iomap() above has most likely
1002 	 * failed because of -EINVAL. If it is equal 0, most likely the table
1003 	 * couldn't be created, indicating -ENOMEM.
1004 	 */
1005 	ret = bar > 0 ? -EINVAL : -ENOMEM;
1006 	legacy_iomap_table = (void __iomem **)pcim_iomap_table(pdev);
1007 
1008 	while (--bar >= 0)
1009 		pcim_iounmap(pdev, legacy_iomap_table[bar]);
1010 
1011 	pcim_release_all_regions(pdev);
1012 
1013 	return ret;
1014 }
1015 EXPORT_SYMBOL(pcim_iomap_regions_request_all);
1016 
1017 /**
1018  * pcim_iounmap_regions - Unmap and release PCI BARs
1019  * @pdev: PCI device to map IO resources for
1020  * @mask: Mask of BARs to unmap and release
1021  *
1022  * Unmap and release regions specified by @mask.
1023  */
pcim_iounmap_regions(struct pci_dev * pdev,int mask)1024 void pcim_iounmap_regions(struct pci_dev *pdev, int mask)
1025 {
1026 	int i;
1027 
1028 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
1029 		if (!mask_contains_bar(mask, i))
1030 			continue;
1031 
1032 		pcim_iounmap_region(pdev, i);
1033 		pcim_remove_bar_from_legacy_table(pdev, i);
1034 	}
1035 }
1036 EXPORT_SYMBOL(pcim_iounmap_regions);
1037 
1038 /**
1039  * pcim_iomap_range - Create a ranged __iomap mapping within a PCI BAR
1040  * @pdev: PCI device to map IO resources for
1041  * @bar: Index of the BAR
1042  * @offset: Offset from the begin of the BAR
1043  * @len: Length in bytes for the mapping
1044  *
1045  * Returns: __iomem pointer on success, an IOMEM_ERR_PTR on failure.
1046  *
1047  * Creates a new IO-Mapping within the specified @bar, ranging from @offset to
1048  * @offset + @len.
1049  *
1050  * The mapping will automatically get unmapped on driver detach. If desired,
1051  * release manually only with pcim_iounmap().
1052  */
pcim_iomap_range(struct pci_dev * pdev,int bar,unsigned long offset,unsigned long len)1053 void __iomem *pcim_iomap_range(struct pci_dev *pdev, int bar,
1054 		unsigned long offset, unsigned long len)
1055 {
1056 	void __iomem *mapping;
1057 	struct pcim_addr_devres *res;
1058 
1059 	res = pcim_addr_devres_alloc(pdev);
1060 	if (!res)
1061 		return IOMEM_ERR_PTR(-ENOMEM);
1062 
1063 	mapping = pci_iomap_range(pdev, bar, offset, len);
1064 	if (!mapping) {
1065 		pcim_addr_devres_free(res);
1066 		return IOMEM_ERR_PTR(-EINVAL);
1067 	}
1068 
1069 	res->type = PCIM_ADDR_DEVRES_TYPE_MAPPING;
1070 	res->baseaddr = mapping;
1071 
1072 	/*
1073 	 * Ranged mappings don't get added to the legacy-table, since the table
1074 	 * only ever keeps track of whole BARs.
1075 	 */
1076 
1077 	devres_add(&pdev->dev, res);
1078 	return mapping;
1079 }
1080 EXPORT_SYMBOL(pcim_iomap_range);
1081