xref: /openbmc/linux/lib/devres.c (revision 29c37341)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/err.h>
3 #include <linux/pci.h>
4 #include <linux/io.h>
5 #include <linux/gfp.h>
6 #include <linux/export.h>
7 #include <linux/of_address.h>
8 
9 enum devm_ioremap_type {
10 	DEVM_IOREMAP = 0,
11 	DEVM_IOREMAP_UC,
12 	DEVM_IOREMAP_WC,
13 };
14 
15 void devm_ioremap_release(struct device *dev, void *res)
16 {
17 	iounmap(*(void __iomem **)res);
18 }
19 
20 static int devm_ioremap_match(struct device *dev, void *res, void *match_data)
21 {
22 	return *(void **)res == match_data;
23 }
24 
25 static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
26 				    resource_size_t size,
27 				    enum devm_ioremap_type type)
28 {
29 	void __iomem **ptr, *addr = NULL;
30 
31 	ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
32 	if (!ptr)
33 		return NULL;
34 
35 	switch (type) {
36 	case DEVM_IOREMAP:
37 		addr = ioremap(offset, size);
38 		break;
39 	case DEVM_IOREMAP_UC:
40 		addr = ioremap_uc(offset, size);
41 		break;
42 	case DEVM_IOREMAP_WC:
43 		addr = ioremap_wc(offset, size);
44 		break;
45 	}
46 
47 	if (addr) {
48 		*ptr = addr;
49 		devres_add(dev, ptr);
50 	} else
51 		devres_free(ptr);
52 
53 	return addr;
54 }
55 
56 /**
57  * devm_ioremap - Managed ioremap()
58  * @dev: Generic device to remap IO address for
59  * @offset: Resource address to map
60  * @size: Size of map
61  *
62  * Managed ioremap().  Map is automatically unmapped on driver detach.
63  */
64 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
65 			   resource_size_t size)
66 {
67 	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP);
68 }
69 EXPORT_SYMBOL(devm_ioremap);
70 
71 /**
72  * devm_ioremap_uc - Managed ioremap_uc()
73  * @dev: Generic device to remap IO address for
74  * @offset: Resource address to map
75  * @size: Size of map
76  *
77  * Managed ioremap_uc().  Map is automatically unmapped on driver detach.
78  */
79 void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
80 			      resource_size_t size)
81 {
82 	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_UC);
83 }
84 EXPORT_SYMBOL_GPL(devm_ioremap_uc);
85 
86 /**
87  * devm_ioremap_wc - Managed ioremap_wc()
88  * @dev: Generic device to remap IO address for
89  * @offset: Resource address to map
90  * @size: Size of map
91  *
92  * Managed ioremap_wc().  Map is automatically unmapped on driver detach.
93  */
94 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
95 			      resource_size_t size)
96 {
97 	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_WC);
98 }
99 EXPORT_SYMBOL(devm_ioremap_wc);
100 
101 /**
102  * devm_iounmap - Managed iounmap()
103  * @dev: Generic device to unmap for
104  * @addr: Address to unmap
105  *
106  * Managed iounmap().  @addr must have been mapped using devm_ioremap*().
107  */
108 void devm_iounmap(struct device *dev, void __iomem *addr)
109 {
110 	WARN_ON(devres_destroy(dev, devm_ioremap_release, devm_ioremap_match,
111 			       (__force void *)addr));
112 	iounmap(addr);
113 }
114 EXPORT_SYMBOL(devm_iounmap);
115 
116 static void __iomem *
117 __devm_ioremap_resource(struct device *dev, const struct resource *res,
118 			enum devm_ioremap_type type)
119 {
120 	resource_size_t size;
121 	void __iomem *dest_ptr;
122 	char *pretty_name;
123 
124 	BUG_ON(!dev);
125 
126 	if (!res || resource_type(res) != IORESOURCE_MEM) {
127 		dev_err(dev, "invalid resource\n");
128 		return IOMEM_ERR_PTR(-EINVAL);
129 	}
130 
131 	size = resource_size(res);
132 
133 	if (res->name)
134 		pretty_name = devm_kasprintf(dev, GFP_KERNEL, "%s %s",
135 					     dev_name(dev), res->name);
136 	else
137 		pretty_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
138 	if (!pretty_name)
139 		return IOMEM_ERR_PTR(-ENOMEM);
140 
141 	if (!devm_request_mem_region(dev, res->start, size, pretty_name)) {
142 		dev_err(dev, "can't request region for resource %pR\n", res);
143 		return IOMEM_ERR_PTR(-EBUSY);
144 	}
145 
146 	dest_ptr = __devm_ioremap(dev, res->start, size, type);
147 	if (!dest_ptr) {
148 		dev_err(dev, "ioremap failed for resource %pR\n", res);
149 		devm_release_mem_region(dev, res->start, size);
150 		dest_ptr = IOMEM_ERR_PTR(-ENOMEM);
151 	}
152 
153 	return dest_ptr;
154 }
155 
156 /**
157  * devm_ioremap_resource() - check, request region, and ioremap resource
158  * @dev: generic device to handle the resource for
159  * @res: resource to be handled
160  *
161  * Checks that a resource is a valid memory region, requests the memory
162  * region and ioremaps it. All operations are managed and will be undone
163  * on driver detach.
164  *
165  * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
166  * on failure. Usage example:
167  *
168  *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
169  *	base = devm_ioremap_resource(&pdev->dev, res);
170  *	if (IS_ERR(base))
171  *		return PTR_ERR(base);
172  */
173 void __iomem *devm_ioremap_resource(struct device *dev,
174 				    const struct resource *res)
175 {
176 	return __devm_ioremap_resource(dev, res, DEVM_IOREMAP);
177 }
178 EXPORT_SYMBOL(devm_ioremap_resource);
179 
180 /**
181  * devm_ioremap_resource_wc() - write-combined variant of
182  *				devm_ioremap_resource()
183  * @dev: generic device to handle the resource for
184  * @res: resource to be handled
185  *
186  * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
187  * on failure. Usage example:
188  */
189 void __iomem *devm_ioremap_resource_wc(struct device *dev,
190 				       const struct resource *res)
191 {
192 	return __devm_ioremap_resource(dev, res, DEVM_IOREMAP_WC);
193 }
194 
195 /*
196  * devm_of_iomap - Requests a resource and maps the memory mapped IO
197  *		   for a given device_node managed by a given device
198  *
199  * Checks that a resource is a valid memory region, requests the memory
200  * region and ioremaps it. All operations are managed and will be undone
201  * on driver detach of the device.
202  *
203  * This is to be used when a device requests/maps resources described
204  * by other device tree nodes (children or otherwise).
205  *
206  * @dev:	The device "managing" the resource
207  * @node:       The device-tree node where the resource resides
208  * @index:	index of the MMIO range in the "reg" property
209  * @size:	Returns the size of the resource (pass NULL if not needed)
210  * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
211  * error code on failure. Usage example:
212  *
213  *	base = devm_of_iomap(&pdev->dev, node, 0, NULL);
214  *	if (IS_ERR(base))
215  *		return PTR_ERR(base);
216  *
217  * Please Note: This is not a one-to-one replacement for of_iomap() because the
218  * of_iomap() function does not track whether the region is already mapped.  If
219  * two drivers try to map the same memory, the of_iomap() function will succeed
220  * but the the devm_of_iomap() function will return -EBUSY.
221  *
222  */
223 void __iomem *devm_of_iomap(struct device *dev, struct device_node *node, int index,
224 			    resource_size_t *size)
225 {
226 	struct resource res;
227 
228 	if (of_address_to_resource(node, index, &res))
229 		return IOMEM_ERR_PTR(-EINVAL);
230 	if (size)
231 		*size = resource_size(&res);
232 	return devm_ioremap_resource(dev, &res);
233 }
234 EXPORT_SYMBOL(devm_of_iomap);
235 
236 #ifdef CONFIG_HAS_IOPORT_MAP
237 /*
238  * Generic iomap devres
239  */
240 static void devm_ioport_map_release(struct device *dev, void *res)
241 {
242 	ioport_unmap(*(void __iomem **)res);
243 }
244 
245 static int devm_ioport_map_match(struct device *dev, void *res,
246 				 void *match_data)
247 {
248 	return *(void **)res == match_data;
249 }
250 
251 /**
252  * devm_ioport_map - Managed ioport_map()
253  * @dev: Generic device to map ioport for
254  * @port: Port to map
255  * @nr: Number of ports to map
256  *
257  * Managed ioport_map().  Map is automatically unmapped on driver
258  * detach.
259  */
260 void __iomem *devm_ioport_map(struct device *dev, unsigned long port,
261 			       unsigned int nr)
262 {
263 	void __iomem **ptr, *addr;
264 
265 	ptr = devres_alloc(devm_ioport_map_release, sizeof(*ptr), GFP_KERNEL);
266 	if (!ptr)
267 		return NULL;
268 
269 	addr = ioport_map(port, nr);
270 	if (addr) {
271 		*ptr = addr;
272 		devres_add(dev, ptr);
273 	} else
274 		devres_free(ptr);
275 
276 	return addr;
277 }
278 EXPORT_SYMBOL(devm_ioport_map);
279 
280 /**
281  * devm_ioport_unmap - Managed ioport_unmap()
282  * @dev: Generic device to unmap for
283  * @addr: Address to unmap
284  *
285  * Managed ioport_unmap().  @addr must have been mapped using
286  * devm_ioport_map().
287  */
288 void devm_ioport_unmap(struct device *dev, void __iomem *addr)
289 {
290 	ioport_unmap(addr);
291 	WARN_ON(devres_destroy(dev, devm_ioport_map_release,
292 			       devm_ioport_map_match, (__force void *)addr));
293 }
294 EXPORT_SYMBOL(devm_ioport_unmap);
295 #endif /* CONFIG_HAS_IOPORT_MAP */
296 
297 #ifdef CONFIG_PCI
298 /*
299  * PCI iomap devres
300  */
301 #define PCIM_IOMAP_MAX	PCI_STD_NUM_BARS
302 
303 struct pcim_iomap_devres {
304 	void __iomem *table[PCIM_IOMAP_MAX];
305 };
306 
307 static void pcim_iomap_release(struct device *gendev, void *res)
308 {
309 	struct pci_dev *dev = to_pci_dev(gendev);
310 	struct pcim_iomap_devres *this = res;
311 	int i;
312 
313 	for (i = 0; i < PCIM_IOMAP_MAX; i++)
314 		if (this->table[i])
315 			pci_iounmap(dev, this->table[i]);
316 }
317 
318 /**
319  * pcim_iomap_table - access iomap allocation table
320  * @pdev: PCI device to access iomap table for
321  *
322  * Access iomap allocation table for @dev.  If iomap table doesn't
323  * exist and @pdev is managed, it will be allocated.  All iomaps
324  * recorded in the iomap table are automatically unmapped on driver
325  * detach.
326  *
327  * This function might sleep when the table is first allocated but can
328  * be safely called without context and guaranteed to succed once
329  * allocated.
330  */
331 void __iomem * const *pcim_iomap_table(struct pci_dev *pdev)
332 {
333 	struct pcim_iomap_devres *dr, *new_dr;
334 
335 	dr = devres_find(&pdev->dev, pcim_iomap_release, NULL, NULL);
336 	if (dr)
337 		return dr->table;
338 
339 	new_dr = devres_alloc(pcim_iomap_release, sizeof(*new_dr), GFP_KERNEL);
340 	if (!new_dr)
341 		return NULL;
342 	dr = devres_get(&pdev->dev, new_dr, NULL, NULL);
343 	return dr->table;
344 }
345 EXPORT_SYMBOL(pcim_iomap_table);
346 
347 /**
348  * pcim_iomap - Managed pcim_iomap()
349  * @pdev: PCI device to iomap for
350  * @bar: BAR to iomap
351  * @maxlen: Maximum length of iomap
352  *
353  * Managed pci_iomap().  Map is automatically unmapped on driver
354  * detach.
355  */
356 void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen)
357 {
358 	void __iomem **tbl;
359 
360 	BUG_ON(bar >= PCIM_IOMAP_MAX);
361 
362 	tbl = (void __iomem **)pcim_iomap_table(pdev);
363 	if (!tbl || tbl[bar])	/* duplicate mappings not allowed */
364 		return NULL;
365 
366 	tbl[bar] = pci_iomap(pdev, bar, maxlen);
367 	return tbl[bar];
368 }
369 EXPORT_SYMBOL(pcim_iomap);
370 
371 /**
372  * pcim_iounmap - Managed pci_iounmap()
373  * @pdev: PCI device to iounmap for
374  * @addr: Address to unmap
375  *
376  * Managed pci_iounmap().  @addr must have been mapped using pcim_iomap().
377  */
378 void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr)
379 {
380 	void __iomem **tbl;
381 	int i;
382 
383 	pci_iounmap(pdev, addr);
384 
385 	tbl = (void __iomem **)pcim_iomap_table(pdev);
386 	BUG_ON(!tbl);
387 
388 	for (i = 0; i < PCIM_IOMAP_MAX; i++)
389 		if (tbl[i] == addr) {
390 			tbl[i] = NULL;
391 			return;
392 		}
393 	WARN_ON(1);
394 }
395 EXPORT_SYMBOL(pcim_iounmap);
396 
397 /**
398  * pcim_iomap_regions - Request and iomap PCI BARs
399  * @pdev: PCI device to map IO resources for
400  * @mask: Mask of BARs to request and iomap
401  * @name: Name used when requesting regions
402  *
403  * Request and iomap regions specified by @mask.
404  */
405 int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
406 {
407 	void __iomem * const *iomap;
408 	int i, rc;
409 
410 	iomap = pcim_iomap_table(pdev);
411 	if (!iomap)
412 		return -ENOMEM;
413 
414 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
415 		unsigned long len;
416 
417 		if (!(mask & (1 << i)))
418 			continue;
419 
420 		rc = -EINVAL;
421 		len = pci_resource_len(pdev, i);
422 		if (!len)
423 			goto err_inval;
424 
425 		rc = pci_request_region(pdev, i, name);
426 		if (rc)
427 			goto err_inval;
428 
429 		rc = -ENOMEM;
430 		if (!pcim_iomap(pdev, i, 0))
431 			goto err_region;
432 	}
433 
434 	return 0;
435 
436  err_region:
437 	pci_release_region(pdev, i);
438  err_inval:
439 	while (--i >= 0) {
440 		if (!(mask & (1 << i)))
441 			continue;
442 		pcim_iounmap(pdev, iomap[i]);
443 		pci_release_region(pdev, i);
444 	}
445 
446 	return rc;
447 }
448 EXPORT_SYMBOL(pcim_iomap_regions);
449 
450 /**
451  * pcim_iomap_regions_request_all - Request all BARs and iomap specified ones
452  * @pdev: PCI device to map IO resources for
453  * @mask: Mask of BARs to iomap
454  * @name: Name used when requesting regions
455  *
456  * Request all PCI BARs and iomap regions specified by @mask.
457  */
458 int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
459 				   const char *name)
460 {
461 	int request_mask = ((1 << 6) - 1) & ~mask;
462 	int rc;
463 
464 	rc = pci_request_selected_regions(pdev, request_mask, name);
465 	if (rc)
466 		return rc;
467 
468 	rc = pcim_iomap_regions(pdev, mask, name);
469 	if (rc)
470 		pci_release_selected_regions(pdev, request_mask);
471 	return rc;
472 }
473 EXPORT_SYMBOL(pcim_iomap_regions_request_all);
474 
475 /**
476  * pcim_iounmap_regions - Unmap and release PCI BARs
477  * @pdev: PCI device to map IO resources for
478  * @mask: Mask of BARs to unmap and release
479  *
480  * Unmap and release regions specified by @mask.
481  */
482 void pcim_iounmap_regions(struct pci_dev *pdev, int mask)
483 {
484 	void __iomem * const *iomap;
485 	int i;
486 
487 	iomap = pcim_iomap_table(pdev);
488 	if (!iomap)
489 		return;
490 
491 	for (i = 0; i < PCIM_IOMAP_MAX; i++) {
492 		if (!(mask & (1 << i)))
493 			continue;
494 
495 		pcim_iounmap(pdev, iomap[i]);
496 		pci_release_region(pdev, i);
497 	}
498 }
499 EXPORT_SYMBOL(pcim_iounmap_regions);
500 #endif /* CONFIG_PCI */
501