xref: /linux/drivers/pci/devres.c (revision dbcedec3a31119d7594baacc743300d127c99c56)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/device.h>
3 #include <linux/pci.h>
4 #include "pci.h"
5 
6 /*
7  * PCI iomap devres
8  */
9 #define PCIM_IOMAP_MAX	PCI_STD_NUM_BARS
10 
11 struct pcim_iomap_devres {
12 	void __iomem *table[PCIM_IOMAP_MAX];
13 };
14 
15 
16 static void devm_pci_unmap_iospace(struct device *dev, void *ptr)
17 {
18 	struct resource **res = ptr;
19 
20 	pci_unmap_iospace(*res);
21 }
22 
23 /**
24  * devm_pci_remap_iospace - Managed pci_remap_iospace()
25  * @dev: Generic device to remap IO address for
26  * @res: Resource describing the I/O space
27  * @phys_addr: physical address of range to be mapped
28  *
29  * Managed pci_remap_iospace().  Map is automatically unmapped on driver
30  * detach.
31  */
32 int devm_pci_remap_iospace(struct device *dev, const struct resource *res,
33 			   phys_addr_t phys_addr)
34 {
35 	const struct resource **ptr;
36 	int error;
37 
38 	ptr = devres_alloc(devm_pci_unmap_iospace, sizeof(*ptr), GFP_KERNEL);
39 	if (!ptr)
40 		return -ENOMEM;
41 
42 	error = pci_remap_iospace(res, phys_addr);
43 	if (error) {
44 		devres_free(ptr);
45 	} else	{
46 		*ptr = res;
47 		devres_add(dev, ptr);
48 	}
49 
50 	return error;
51 }
52 EXPORT_SYMBOL(devm_pci_remap_iospace);
53 
54 /**
55  * devm_pci_remap_cfgspace - Managed pci_remap_cfgspace()
56  * @dev: Generic device to remap IO address for
57  * @offset: Resource address to map
58  * @size: Size of map
59  *
60  * Managed pci_remap_cfgspace().  Map is automatically unmapped on driver
61  * detach.
62  */
63 void __iomem *devm_pci_remap_cfgspace(struct device *dev,
64 				      resource_size_t offset,
65 				      resource_size_t size)
66 {
67 	void __iomem **ptr, *addr;
68 
69 	ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
70 	if (!ptr)
71 		return NULL;
72 
73 	addr = pci_remap_cfgspace(offset, size);
74 	if (addr) {
75 		*ptr = addr;
76 		devres_add(dev, ptr);
77 	} else
78 		devres_free(ptr);
79 
80 	return addr;
81 }
82 EXPORT_SYMBOL(devm_pci_remap_cfgspace);
83 
84 /**
85  * devm_pci_remap_cfg_resource - check, request region and ioremap cfg resource
86  * @dev: generic device to handle the resource for
87  * @res: configuration space resource to be handled
88  *
89  * Checks that a resource is a valid memory region, requests the memory
90  * region and ioremaps with pci_remap_cfgspace() API that ensures the
91  * proper PCI configuration space memory attributes are guaranteed.
92  *
93  * All operations are managed and will be undone on driver detach.
94  *
95  * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
96  * on failure. Usage example::
97  *
98  *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
99  *	base = devm_pci_remap_cfg_resource(&pdev->dev, res);
100  *	if (IS_ERR(base))
101  *		return PTR_ERR(base);
102  */
103 void __iomem *devm_pci_remap_cfg_resource(struct device *dev,
104 					  struct resource *res)
105 {
106 	resource_size_t size;
107 	const char *name;
108 	void __iomem *dest_ptr;
109 
110 	BUG_ON(!dev);
111 
112 	if (!res || resource_type(res) != IORESOURCE_MEM) {
113 		dev_err(dev, "invalid resource\n");
114 		return IOMEM_ERR_PTR(-EINVAL);
115 	}
116 
117 	size = resource_size(res);
118 
119 	if (res->name)
120 		name = devm_kasprintf(dev, GFP_KERNEL, "%s %s", dev_name(dev),
121 				      res->name);
122 	else
123 		name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
124 	if (!name)
125 		return IOMEM_ERR_PTR(-ENOMEM);
126 
127 	if (!devm_request_mem_region(dev, res->start, size, name)) {
128 		dev_err(dev, "can't request region for resource %pR\n", res);
129 		return IOMEM_ERR_PTR(-EBUSY);
130 	}
131 
132 	dest_ptr = devm_pci_remap_cfgspace(dev, res->start, size);
133 	if (!dest_ptr) {
134 		dev_err(dev, "ioremap failed for resource %pR\n", res);
135 		devm_release_mem_region(dev, res->start, size);
136 		dest_ptr = IOMEM_ERR_PTR(-ENOMEM);
137 	}
138 
139 	return dest_ptr;
140 }
141 EXPORT_SYMBOL(devm_pci_remap_cfg_resource);
142 
143 /**
144  * pcim_set_mwi - a device-managed pci_set_mwi()
145  * @dev: the PCI device for which MWI is enabled
146  *
147  * Managed pci_set_mwi().
148  *
149  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
150  */
151 int pcim_set_mwi(struct pci_dev *dev)
152 {
153 	struct pci_devres *dr;
154 
155 	dr = find_pci_dr(dev);
156 	if (!dr)
157 		return -ENOMEM;
158 
159 	dr->mwi = 1;
160 	return pci_set_mwi(dev);
161 }
162 EXPORT_SYMBOL(pcim_set_mwi);
163 
164 
165 static void pcim_release(struct device *gendev, void *res)
166 {
167 	struct pci_dev *dev = to_pci_dev(gendev);
168 	struct pci_devres *this = res;
169 	int i;
170 
171 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
172 		if (this->region_mask & (1 << i))
173 			pci_release_region(dev, i);
174 
175 	if (this->mwi)
176 		pci_clear_mwi(dev);
177 
178 	if (this->restore_intx)
179 		pci_intx(dev, this->orig_intx);
180 
181 	if (this->enabled && !this->pinned)
182 		pci_disable_device(dev);
183 }
184 
185 /*
186  * TODO: After the last four callers in pci.c are ported, find_pci_dr()
187  * needs to be made static again.
188  */
189 struct pci_devres *find_pci_dr(struct pci_dev *pdev)
190 {
191 	if (pci_is_managed(pdev))
192 		return devres_find(&pdev->dev, pcim_release, NULL, NULL);
193 	return NULL;
194 }
195 
196 static struct pci_devres *get_pci_dr(struct pci_dev *pdev)
197 {
198 	struct pci_devres *dr, *new_dr;
199 
200 	dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
201 	if (dr)
202 		return dr;
203 
204 	new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
205 	if (!new_dr)
206 		return NULL;
207 	return devres_get(&pdev->dev, new_dr, NULL, NULL);
208 }
209 
210 /**
211  * pcim_enable_device - Managed pci_enable_device()
212  * @pdev: PCI device to be initialized
213  *
214  * Managed pci_enable_device().
215  */
216 int pcim_enable_device(struct pci_dev *pdev)
217 {
218 	struct pci_devres *dr;
219 	int rc;
220 
221 	dr = get_pci_dr(pdev);
222 	if (unlikely(!dr))
223 		return -ENOMEM;
224 	if (dr->enabled)
225 		return 0;
226 
227 	rc = pci_enable_device(pdev);
228 	if (!rc) {
229 		pdev->is_managed = 1;
230 		dr->enabled = 1;
231 	}
232 	return rc;
233 }
234 EXPORT_SYMBOL(pcim_enable_device);
235 
236 /**
237  * pcim_pin_device - Pin managed PCI device
238  * @pdev: PCI device to pin
239  *
240  * Pin managed PCI device @pdev.  Pinned device won't be disabled on
241  * driver detach.  @pdev must have been enabled with
242  * pcim_enable_device().
243  */
244 void pcim_pin_device(struct pci_dev *pdev)
245 {
246 	struct pci_devres *dr;
247 
248 	dr = find_pci_dr(pdev);
249 	WARN_ON(!dr || !dr->enabled);
250 	if (dr)
251 		dr->pinned = 1;
252 }
253 EXPORT_SYMBOL(pcim_pin_device);
254 
255 static void pcim_iomap_release(struct device *gendev, void *res)
256 {
257 	struct pci_dev *dev = to_pci_dev(gendev);
258 	struct pcim_iomap_devres *this = res;
259 	int i;
260 
261 	for (i = 0; i < PCIM_IOMAP_MAX; i++)
262 		if (this->table[i])
263 			pci_iounmap(dev, this->table[i]);
264 }
265 
266 /**
267  * pcim_iomap_table - access iomap allocation table
268  * @pdev: PCI device to access iomap table for
269  *
270  * Access iomap allocation table for @dev.  If iomap table doesn't
271  * exist and @pdev is managed, it will be allocated.  All iomaps
272  * recorded in the iomap table are automatically unmapped on driver
273  * detach.
274  *
275  * This function might sleep when the table is first allocated but can
276  * be safely called without context and guaranteed to succeed once
277  * allocated.
278  */
279 void __iomem * const *pcim_iomap_table(struct pci_dev *pdev)
280 {
281 	struct pcim_iomap_devres *dr, *new_dr;
282 
283 	dr = devres_find(&pdev->dev, pcim_iomap_release, NULL, NULL);
284 	if (dr)
285 		return dr->table;
286 
287 	new_dr = devres_alloc_node(pcim_iomap_release, sizeof(*new_dr), GFP_KERNEL,
288 				   dev_to_node(&pdev->dev));
289 	if (!new_dr)
290 		return NULL;
291 	dr = devres_get(&pdev->dev, new_dr, NULL, NULL);
292 	return dr->table;
293 }
294 EXPORT_SYMBOL(pcim_iomap_table);
295 
296 /**
297  * pcim_iomap - Managed pcim_iomap()
298  * @pdev: PCI device to iomap for
299  * @bar: BAR to iomap
300  * @maxlen: Maximum length of iomap
301  *
302  * Managed pci_iomap().  Map is automatically unmapped on driver
303  * detach.
304  */
305 void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen)
306 {
307 	void __iomem **tbl;
308 
309 	BUG_ON(bar >= PCIM_IOMAP_MAX);
310 
311 	tbl = (void __iomem **)pcim_iomap_table(pdev);
312 	if (!tbl || tbl[bar])	/* duplicate mappings not allowed */
313 		return NULL;
314 
315 	tbl[bar] = pci_iomap(pdev, bar, maxlen);
316 	return tbl[bar];
317 }
318 EXPORT_SYMBOL(pcim_iomap);
319 
320 /**
321  * pcim_iounmap - Managed pci_iounmap()
322  * @pdev: PCI device to iounmap for
323  * @addr: Address to unmap
324  *
325  * Managed pci_iounmap().  @addr must have been mapped using pcim_iomap().
326  */
327 void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr)
328 {
329 	void __iomem **tbl;
330 	int i;
331 
332 	pci_iounmap(pdev, addr);
333 
334 	tbl = (void __iomem **)pcim_iomap_table(pdev);
335 	BUG_ON(!tbl);
336 
337 	for (i = 0; i < PCIM_IOMAP_MAX; i++)
338 		if (tbl[i] == addr) {
339 			tbl[i] = NULL;
340 			return;
341 		}
342 	WARN_ON(1);
343 }
344 EXPORT_SYMBOL(pcim_iounmap);
345 
346 /**
347  * pcim_iomap_regions - Request and iomap PCI BARs
348  * @pdev: PCI device to map IO resources for
349  * @mask: Mask of BARs to request and iomap
350  * @name: Name used when requesting regions
351  *
352  * Request and iomap regions specified by @mask.
353  */
354 int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
355 {
356 	void __iomem * const *iomap;
357 	int i, rc;
358 
359 	iomap = pcim_iomap_table(pdev);
360 	if (!iomap)
361 		return -ENOMEM;
362 
363 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
364 		unsigned long len;
365 
366 		if (!(mask & (1 << i)))
367 			continue;
368 
369 		rc = -EINVAL;
370 		len = pci_resource_len(pdev, i);
371 		if (!len)
372 			goto err_inval;
373 
374 		rc = pci_request_region(pdev, i, name);
375 		if (rc)
376 			goto err_inval;
377 
378 		rc = -ENOMEM;
379 		if (!pcim_iomap(pdev, i, 0))
380 			goto err_region;
381 	}
382 
383 	return 0;
384 
385  err_region:
386 	pci_release_region(pdev, i);
387  err_inval:
388 	while (--i >= 0) {
389 		if (!(mask & (1 << i)))
390 			continue;
391 		pcim_iounmap(pdev, iomap[i]);
392 		pci_release_region(pdev, i);
393 	}
394 
395 	return rc;
396 }
397 EXPORT_SYMBOL(pcim_iomap_regions);
398 
399 /**
400  * pcim_iomap_regions_request_all - Request all BARs and iomap specified ones
401  * @pdev: PCI device to map IO resources for
402  * @mask: Mask of BARs to iomap
403  * @name: Name used when requesting regions
404  *
405  * Request all PCI BARs and iomap regions specified by @mask.
406  */
407 int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
408 				   const char *name)
409 {
410 	int request_mask = ((1 << 6) - 1) & ~mask;
411 	int rc;
412 
413 	rc = pci_request_selected_regions(pdev, request_mask, name);
414 	if (rc)
415 		return rc;
416 
417 	rc = pcim_iomap_regions(pdev, mask, name);
418 	if (rc)
419 		pci_release_selected_regions(pdev, request_mask);
420 	return rc;
421 }
422 EXPORT_SYMBOL(pcim_iomap_regions_request_all);
423 
424 /**
425  * pcim_iounmap_regions - Unmap and release PCI BARs
426  * @pdev: PCI device to map IO resources for
427  * @mask: Mask of BARs to unmap and release
428  *
429  * Unmap and release regions specified by @mask.
430  */
431 void pcim_iounmap_regions(struct pci_dev *pdev, int mask)
432 {
433 	void __iomem * const *iomap;
434 	int i;
435 
436 	iomap = pcim_iomap_table(pdev);
437 	if (!iomap)
438 		return;
439 
440 	for (i = 0; i < PCIM_IOMAP_MAX; i++) {
441 		if (!(mask & (1 << i)))
442 			continue;
443 
444 		pcim_iounmap(pdev, iomap[i]);
445 		pci_release_region(pdev, i);
446 	}
447 }
448 EXPORT_SYMBOL(pcim_iounmap_regions);
449