xref: /openbmc/linux/lib/devres.c (revision 4cff79e9)
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 
8 enum devm_ioremap_type {
9 	DEVM_IOREMAP = 0,
10 	DEVM_IOREMAP_NC,
11 	DEVM_IOREMAP_WC,
12 };
13 
14 void devm_ioremap_release(struct device *dev, void *res)
15 {
16 	iounmap(*(void __iomem **)res);
17 }
18 
19 static int devm_ioremap_match(struct device *dev, void *res, void *match_data)
20 {
21 	return *(void **)res == match_data;
22 }
23 
24 static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
25 				    resource_size_t size,
26 				    enum devm_ioremap_type type)
27 {
28 	void __iomem **ptr, *addr = NULL;
29 
30 	ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
31 	if (!ptr)
32 		return NULL;
33 
34 	switch (type) {
35 	case DEVM_IOREMAP:
36 		addr = ioremap(offset, size);
37 		break;
38 	case DEVM_IOREMAP_NC:
39 		addr = ioremap_nocache(offset, size);
40 		break;
41 	case DEVM_IOREMAP_WC:
42 		addr = ioremap_wc(offset, size);
43 		break;
44 	}
45 
46 	if (addr) {
47 		*ptr = addr;
48 		devres_add(dev, ptr);
49 	} else
50 		devres_free(ptr);
51 
52 	return addr;
53 }
54 
55 /**
56  * devm_ioremap - Managed ioremap()
57  * @dev: Generic device to remap IO address for
58  * @offset: Resource address to map
59  * @size: Size of map
60  *
61  * Managed ioremap().  Map is automatically unmapped on driver detach.
62  */
63 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
64 			   resource_size_t size)
65 {
66 	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP);
67 }
68 EXPORT_SYMBOL(devm_ioremap);
69 
70 /**
71  * devm_ioremap_nocache - Managed ioremap_nocache()
72  * @dev: Generic device to remap IO address for
73  * @offset: Resource address to map
74  * @size: Size of map
75  *
76  * Managed ioremap_nocache().  Map is automatically unmapped on driver
77  * detach.
78  */
79 void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
80 				   resource_size_t size)
81 {
82 	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_NC);
83 }
84 EXPORT_SYMBOL(devm_ioremap_nocache);
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 /**
117  * devm_ioremap_resource() - check, request region, and ioremap resource
118  * @dev: generic device to handle the resource for
119  * @res: resource to be handled
120  *
121  * Checks that a resource is a valid memory region, requests the memory
122  * region and ioremaps it. All operations are managed and will be undone
123  * on driver detach.
124  *
125  * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
126  * on failure. Usage example:
127  *
128  *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
129  *	base = devm_ioremap_resource(&pdev->dev, res);
130  *	if (IS_ERR(base))
131  *		return PTR_ERR(base);
132  */
133 void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res)
134 {
135 	resource_size_t size;
136 	const char *name;
137 	void __iomem *dest_ptr;
138 
139 	BUG_ON(!dev);
140 
141 	if (!res || resource_type(res) != IORESOURCE_MEM) {
142 		dev_err(dev, "invalid resource\n");
143 		return IOMEM_ERR_PTR(-EINVAL);
144 	}
145 
146 	size = resource_size(res);
147 	name = res->name ?: dev_name(dev);
148 
149 	if (!devm_request_mem_region(dev, res->start, size, name)) {
150 		dev_err(dev, "can't request region for resource %pR\n", res);
151 		return IOMEM_ERR_PTR(-EBUSY);
152 	}
153 
154 	dest_ptr = devm_ioremap(dev, res->start, size);
155 	if (!dest_ptr) {
156 		dev_err(dev, "ioremap failed for resource %pR\n", res);
157 		devm_release_mem_region(dev, res->start, size);
158 		dest_ptr = IOMEM_ERR_PTR(-ENOMEM);
159 	}
160 
161 	return dest_ptr;
162 }
163 EXPORT_SYMBOL(devm_ioremap_resource);
164 
165 #ifdef CONFIG_HAS_IOPORT_MAP
166 /*
167  * Generic iomap devres
168  */
169 static void devm_ioport_map_release(struct device *dev, void *res)
170 {
171 	ioport_unmap(*(void __iomem **)res);
172 }
173 
174 static int devm_ioport_map_match(struct device *dev, void *res,
175 				 void *match_data)
176 {
177 	return *(void **)res == match_data;
178 }
179 
180 /**
181  * devm_ioport_map - Managed ioport_map()
182  * @dev: Generic device to map ioport for
183  * @port: Port to map
184  * @nr: Number of ports to map
185  *
186  * Managed ioport_map().  Map is automatically unmapped on driver
187  * detach.
188  */
189 void __iomem *devm_ioport_map(struct device *dev, unsigned long port,
190 			       unsigned int nr)
191 {
192 	void __iomem **ptr, *addr;
193 
194 	ptr = devres_alloc(devm_ioport_map_release, sizeof(*ptr), GFP_KERNEL);
195 	if (!ptr)
196 		return NULL;
197 
198 	addr = ioport_map(port, nr);
199 	if (addr) {
200 		*ptr = addr;
201 		devres_add(dev, ptr);
202 	} else
203 		devres_free(ptr);
204 
205 	return addr;
206 }
207 EXPORT_SYMBOL(devm_ioport_map);
208 
209 /**
210  * devm_ioport_unmap - Managed ioport_unmap()
211  * @dev: Generic device to unmap for
212  * @addr: Address to unmap
213  *
214  * Managed ioport_unmap().  @addr must have been mapped using
215  * devm_ioport_map().
216  */
217 void devm_ioport_unmap(struct device *dev, void __iomem *addr)
218 {
219 	ioport_unmap(addr);
220 	WARN_ON(devres_destroy(dev, devm_ioport_map_release,
221 			       devm_ioport_map_match, (__force void *)addr));
222 }
223 EXPORT_SYMBOL(devm_ioport_unmap);
224 #endif /* CONFIG_HAS_IOPORT_MAP */
225 
226 #ifdef CONFIG_PCI
227 /*
228  * PCI iomap devres
229  */
230 #define PCIM_IOMAP_MAX	PCI_ROM_RESOURCE
231 
232 struct pcim_iomap_devres {
233 	void __iomem *table[PCIM_IOMAP_MAX];
234 };
235 
236 static void pcim_iomap_release(struct device *gendev, void *res)
237 {
238 	struct pci_dev *dev = to_pci_dev(gendev);
239 	struct pcim_iomap_devres *this = res;
240 	int i;
241 
242 	for (i = 0; i < PCIM_IOMAP_MAX; i++)
243 		if (this->table[i])
244 			pci_iounmap(dev, this->table[i]);
245 }
246 
247 /**
248  * pcim_iomap_table - access iomap allocation table
249  * @pdev: PCI device to access iomap table for
250  *
251  * Access iomap allocation table for @dev.  If iomap table doesn't
252  * exist and @pdev is managed, it will be allocated.  All iomaps
253  * recorded in the iomap table are automatically unmapped on driver
254  * detach.
255  *
256  * This function might sleep when the table is first allocated but can
257  * be safely called without context and guaranteed to succed once
258  * allocated.
259  */
260 void __iomem * const *pcim_iomap_table(struct pci_dev *pdev)
261 {
262 	struct pcim_iomap_devres *dr, *new_dr;
263 
264 	dr = devres_find(&pdev->dev, pcim_iomap_release, NULL, NULL);
265 	if (dr)
266 		return dr->table;
267 
268 	new_dr = devres_alloc(pcim_iomap_release, sizeof(*new_dr), GFP_KERNEL);
269 	if (!new_dr)
270 		return NULL;
271 	dr = devres_get(&pdev->dev, new_dr, NULL, NULL);
272 	return dr->table;
273 }
274 EXPORT_SYMBOL(pcim_iomap_table);
275 
276 /**
277  * pcim_iomap - Managed pcim_iomap()
278  * @pdev: PCI device to iomap for
279  * @bar: BAR to iomap
280  * @maxlen: Maximum length of iomap
281  *
282  * Managed pci_iomap().  Map is automatically unmapped on driver
283  * detach.
284  */
285 void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen)
286 {
287 	void __iomem **tbl;
288 
289 	BUG_ON(bar >= PCIM_IOMAP_MAX);
290 
291 	tbl = (void __iomem **)pcim_iomap_table(pdev);
292 	if (!tbl || tbl[bar])	/* duplicate mappings not allowed */
293 		return NULL;
294 
295 	tbl[bar] = pci_iomap(pdev, bar, maxlen);
296 	return tbl[bar];
297 }
298 EXPORT_SYMBOL(pcim_iomap);
299 
300 /**
301  * pcim_iounmap - Managed pci_iounmap()
302  * @pdev: PCI device to iounmap for
303  * @addr: Address to unmap
304  *
305  * Managed pci_iounmap().  @addr must have been mapped using pcim_iomap().
306  */
307 void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr)
308 {
309 	void __iomem **tbl;
310 	int i;
311 
312 	pci_iounmap(pdev, addr);
313 
314 	tbl = (void __iomem **)pcim_iomap_table(pdev);
315 	BUG_ON(!tbl);
316 
317 	for (i = 0; i < PCIM_IOMAP_MAX; i++)
318 		if (tbl[i] == addr) {
319 			tbl[i] = NULL;
320 			return;
321 		}
322 	WARN_ON(1);
323 }
324 EXPORT_SYMBOL(pcim_iounmap);
325 
326 /**
327  * pcim_iomap_regions - Request and iomap PCI BARs
328  * @pdev: PCI device to map IO resources for
329  * @mask: Mask of BARs to request and iomap
330  * @name: Name used when requesting regions
331  *
332  * Request and iomap regions specified by @mask.
333  */
334 int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
335 {
336 	void __iomem * const *iomap;
337 	int i, rc;
338 
339 	iomap = pcim_iomap_table(pdev);
340 	if (!iomap)
341 		return -ENOMEM;
342 
343 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
344 		unsigned long len;
345 
346 		if (!(mask & (1 << i)))
347 			continue;
348 
349 		rc = -EINVAL;
350 		len = pci_resource_len(pdev, i);
351 		if (!len)
352 			goto err_inval;
353 
354 		rc = pci_request_region(pdev, i, name);
355 		if (rc)
356 			goto err_inval;
357 
358 		rc = -ENOMEM;
359 		if (!pcim_iomap(pdev, i, 0))
360 			goto err_region;
361 	}
362 
363 	return 0;
364 
365  err_region:
366 	pci_release_region(pdev, i);
367  err_inval:
368 	while (--i >= 0) {
369 		if (!(mask & (1 << i)))
370 			continue;
371 		pcim_iounmap(pdev, iomap[i]);
372 		pci_release_region(pdev, i);
373 	}
374 
375 	return rc;
376 }
377 EXPORT_SYMBOL(pcim_iomap_regions);
378 
379 /**
380  * pcim_iomap_regions_request_all - Request all BARs and iomap specified ones
381  * @pdev: PCI device to map IO resources for
382  * @mask: Mask of BARs to iomap
383  * @name: Name used when requesting regions
384  *
385  * Request all PCI BARs and iomap regions specified by @mask.
386  */
387 int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
388 				   const char *name)
389 {
390 	int request_mask = ((1 << 6) - 1) & ~mask;
391 	int rc;
392 
393 	rc = pci_request_selected_regions(pdev, request_mask, name);
394 	if (rc)
395 		return rc;
396 
397 	rc = pcim_iomap_regions(pdev, mask, name);
398 	if (rc)
399 		pci_release_selected_regions(pdev, request_mask);
400 	return rc;
401 }
402 EXPORT_SYMBOL(pcim_iomap_regions_request_all);
403 
404 /**
405  * pcim_iounmap_regions - Unmap and release PCI BARs
406  * @pdev: PCI device to map IO resources for
407  * @mask: Mask of BARs to unmap and release
408  *
409  * Unmap and release regions specified by @mask.
410  */
411 void pcim_iounmap_regions(struct pci_dev *pdev, int mask)
412 {
413 	void __iomem * const *iomap;
414 	int i;
415 
416 	iomap = pcim_iomap_table(pdev);
417 	if (!iomap)
418 		return;
419 
420 	for (i = 0; i < PCIM_IOMAP_MAX; i++) {
421 		if (!(mask & (1 << i)))
422 			continue;
423 
424 		pcim_iounmap(pdev, iomap[i]);
425 		pci_release_region(pdev, i);
426 	}
427 }
428 EXPORT_SYMBOL(pcim_iounmap_regions);
429 #endif /* CONFIG_PCI */
430