xref: /linux/drivers/pci/setup-res.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  *	drivers/pci/setup-res.c
3  *
4  * Extruded from code written by
5  *      Dave Rusling (david.rusling@reo.mts.dec.com)
6  *      David Mosberger (davidm@cs.arizona.edu)
7  *	David Miller (davem@redhat.com)
8  *
9  * Support routines for initializing a PCI subsystem.
10  */
11 
12 /* fixed for multiple pci buses, 1999 Andrea Arcangeli <andrea@suse.de> */
13 
14 /*
15  * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
16  *	     Resource sorting
17  */
18 
19 #include <linux/init.h>
20 #include <linux/kernel.h>
21 #include <linux/export.h>
22 #include <linux/pci.h>
23 #include <linux/errno.h>
24 #include <linux/ioport.h>
25 #include <linux/cache.h>
26 #include <linux/slab.h>
27 #include "pci.h"
28 
29 
30 void pci_update_resource(struct pci_dev *dev, int resno)
31 {
32 	struct pci_bus_region region;
33 	u32 new, check, mask;
34 	int reg;
35 	enum pci_bar_type type;
36 	struct resource *res = dev->resource + resno;
37 
38 	/*
39 	 * Ignore resources for unimplemented BARs and unused resource slots
40 	 * for 64 bit BARs.
41 	 */
42 	if (!res->flags)
43 		return;
44 
45 	/*
46 	 * Ignore non-moveable resources.  This might be legacy resources for
47 	 * which no functional BAR register exists or another important
48 	 * system resource we shouldn't move around.
49 	 */
50 	if (res->flags & IORESOURCE_PCI_FIXED)
51 		return;
52 
53 	pcibios_resource_to_bus(dev, &region, res);
54 
55 	new = region.start | (res->flags & PCI_REGION_FLAG_MASK);
56 	if (res->flags & IORESOURCE_IO)
57 		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
58 	else
59 		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
60 
61 	reg = pci_resource_bar(dev, resno, &type);
62 	if (!reg)
63 		return;
64 	if (type != pci_bar_unknown) {
65 		if (!(res->flags & IORESOURCE_ROM_ENABLE))
66 			return;
67 		new |= PCI_ROM_ADDRESS_ENABLE;
68 	}
69 
70 	pci_write_config_dword(dev, reg, new);
71 	pci_read_config_dword(dev, reg, &check);
72 
73 	if ((new ^ check) & mask) {
74 		dev_err(&dev->dev, "BAR %d: error updating (%#08x != %#08x)\n",
75 			resno, new, check);
76 	}
77 
78 	if (res->flags & IORESOURCE_MEM_64) {
79 		new = region.start >> 16 >> 16;
80 		pci_write_config_dword(dev, reg + 4, new);
81 		pci_read_config_dword(dev, reg + 4, &check);
82 		if (check != new) {
83 			dev_err(&dev->dev, "BAR %d: error updating "
84 			       "(high %#08x != %#08x)\n", resno, new, check);
85 		}
86 	}
87 	res->flags &= ~IORESOURCE_UNSET;
88 	dev_info(&dev->dev, "BAR %d: set to %pR (PCI address [%#llx-%#llx])\n",
89 		 resno, res, (unsigned long long)region.start,
90 		 (unsigned long long)region.end);
91 }
92 
93 int pci_claim_resource(struct pci_dev *dev, int resource)
94 {
95 	struct resource *res = &dev->resource[resource];
96 	struct resource *root, *conflict;
97 
98 	root = pci_find_parent_resource(dev, res);
99 	if (!root) {
100 		dev_info(&dev->dev, "no compatible bridge window for %pR\n",
101 			 res);
102 		return -EINVAL;
103 	}
104 
105 	conflict = request_resource_conflict(root, res);
106 	if (conflict) {
107 		dev_info(&dev->dev,
108 			 "address space collision: %pR conflicts with %s %pR\n",
109 			 res, conflict->name, conflict);
110 		return -EBUSY;
111 	}
112 
113 	return 0;
114 }
115 EXPORT_SYMBOL(pci_claim_resource);
116 
117 #ifdef CONFIG_PCI_QUIRKS
118 void pci_disable_bridge_window(struct pci_dev *dev)
119 {
120 	dev_info(&dev->dev, "disabling bridge mem windows\n");
121 
122 	/* MMIO Base/Limit */
123 	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
124 
125 	/* Prefetchable MMIO Base/Limit */
126 	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
127 	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
128 	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
129 }
130 #endif	/* CONFIG_PCI_QUIRKS */
131 
132 
133 
134 static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
135 		int resno, resource_size_t size, resource_size_t align)
136 {
137 	struct resource *res = dev->resource + resno;
138 	resource_size_t min;
139 	int ret;
140 
141 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
142 
143 	/* First, try exact prefetching match.. */
144 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
145 				     IORESOURCE_PREFETCH,
146 				     pcibios_align_resource, dev);
147 
148 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
149 		/*
150 		 * That failed.
151 		 *
152 		 * But a prefetching area can handle a non-prefetching
153 		 * window (it will just not perform as well).
154 		 */
155 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
156 					     pcibios_align_resource, dev);
157 	}
158 	return ret;
159 }
160 
161 static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
162 		int resno, resource_size_t size)
163 {
164 	struct resource *root, *conflict;
165 	resource_size_t start, end;
166 	int ret = 0;
167 
168 	if (res->flags & IORESOURCE_IO)
169 		root = &ioport_resource;
170 	else
171 		root = &iomem_resource;
172 
173 	start = res->start;
174 	end = res->end;
175 	res->start = dev->fw_addr[resno];
176 	res->end = res->start + size - 1;
177 	dev_info(&dev->dev, "BAR %d: trying firmware assignment %pR\n",
178 		 resno, res);
179 	conflict = request_resource_conflict(root, res);
180 	if (conflict) {
181 		dev_info(&dev->dev,
182 			 "BAR %d: %pR conflicts with %s %pR\n", resno,
183 			 res, conflict->name, conflict);
184 		res->start = start;
185 		res->end = end;
186 		ret = 1;
187 	}
188 	return ret;
189 }
190 
191 static int _pci_assign_resource(struct pci_dev *dev, int resno, int size, resource_size_t min_align)
192 {
193 	struct resource *res = dev->resource + resno;
194 	struct pci_bus *bus;
195 	int ret;
196 	char *type;
197 
198 	bus = dev->bus;
199 	while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
200 		if (!bus->parent || !bus->self->transparent)
201 			break;
202 		bus = bus->parent;
203 	}
204 
205 	if (ret) {
206 		if (res->flags & IORESOURCE_MEM)
207 			if (res->flags & IORESOURCE_PREFETCH)
208 				type = "mem pref";
209 			else
210 				type = "mem";
211 		else if (res->flags & IORESOURCE_IO)
212 			type = "io";
213 		else
214 			type = "unknown";
215 		dev_info(&dev->dev,
216 			 "BAR %d: can't assign %s (size %#llx)\n",
217 			 resno, type, (unsigned long long) resource_size(res));
218 	}
219 
220 	return ret;
221 }
222 
223 int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsize,
224 			resource_size_t min_align)
225 {
226 	struct resource *res = dev->resource + resno;
227 	resource_size_t new_size;
228 	int ret;
229 
230 	if (!res->parent) {
231 		dev_info(&dev->dev, "BAR %d: can't reassign an unassigned resouce %pR "
232 			 "\n", resno, res);
233 		return -EINVAL;
234 	}
235 
236 	new_size = resource_size(res) + addsize + min_align;
237 	ret = _pci_assign_resource(dev, resno, new_size, min_align);
238 	if (!ret) {
239 		res->flags &= ~IORESOURCE_STARTALIGN;
240 		dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
241 		if (resno < PCI_BRIDGE_RESOURCES)
242 			pci_update_resource(dev, resno);
243 	}
244 	return ret;
245 }
246 
247 int pci_assign_resource(struct pci_dev *dev, int resno)
248 {
249 	struct resource *res = dev->resource + resno;
250 	resource_size_t align, size;
251 	struct pci_bus *bus;
252 	int ret;
253 
254 	align = pci_resource_alignment(dev, res);
255 	if (!align) {
256 		dev_info(&dev->dev, "BAR %d: can't assign %pR "
257 			 "(bogus alignment)\n", resno, res);
258 		return -EINVAL;
259 	}
260 
261 	bus = dev->bus;
262 	size = resource_size(res);
263 	ret = _pci_assign_resource(dev, resno, size, align);
264 
265 	/*
266 	 * If we failed to assign anything, let's try the address
267 	 * where firmware left it.  That at least has a chance of
268 	 * working, which is better than just leaving it disabled.
269 	 */
270 	if (ret < 0 && dev->fw_addr[resno])
271 		ret = pci_revert_fw_address(res, dev, resno, size);
272 
273 	if (!ret) {
274 		res->flags &= ~IORESOURCE_STARTALIGN;
275 		dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
276 		if (resno < PCI_BRIDGE_RESOURCES)
277 			pci_update_resource(dev, resno);
278 	}
279 	return ret;
280 }
281 
282 
283 /* Sort resources by alignment */
284 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
285 {
286 	int i;
287 
288 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
289 		struct resource *r;
290 		struct resource_list *list, *tmp;
291 		resource_size_t r_align;
292 
293 		r = &dev->resource[i];
294 
295 		if (r->flags & IORESOURCE_PCI_FIXED)
296 			continue;
297 
298 		if (!(r->flags) || r->parent)
299 			continue;
300 
301 		r_align = pci_resource_alignment(dev, r);
302 		if (!r_align) {
303 			dev_warn(&dev->dev, "BAR %d: %pR has bogus alignment\n",
304 				 i, r);
305 			continue;
306 		}
307 		for (list = head; ; list = list->next) {
308 			resource_size_t align = 0;
309 			struct resource_list *ln = list->next;
310 
311 			if (ln)
312 				align = pci_resource_alignment(ln->dev, ln->res);
313 
314 			if (r_align > align) {
315 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
316 				if (!tmp)
317 					panic("pdev_sort_resources(): "
318 					      "kmalloc() failed!\n");
319 				tmp->next = ln;
320 				tmp->res = r;
321 				tmp->dev = dev;
322 				list->next = tmp;
323 				break;
324 			}
325 		}
326 	}
327 }
328 
329 int pci_enable_resources(struct pci_dev *dev, int mask)
330 {
331 	u16 cmd, old_cmd;
332 	int i;
333 	struct resource *r;
334 
335 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
336 	old_cmd = cmd;
337 
338 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
339 		if (!(mask & (1 << i)))
340 			continue;
341 
342 		r = &dev->resource[i];
343 
344 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
345 			continue;
346 		if ((i == PCI_ROM_RESOURCE) &&
347 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
348 			continue;
349 
350 		if (!r->parent) {
351 			dev_err(&dev->dev, "device not available "
352 				"(can't reserve %pR)\n", r);
353 			return -EINVAL;
354 		}
355 
356 		if (r->flags & IORESOURCE_IO)
357 			cmd |= PCI_COMMAND_IO;
358 		if (r->flags & IORESOURCE_MEM)
359 			cmd |= PCI_COMMAND_MEMORY;
360 	}
361 
362 	if (cmd != old_cmd) {
363 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
364 			 old_cmd, cmd);
365 		pci_write_config_word(dev, PCI_COMMAND, cmd);
366 	}
367 	return 0;
368 }
369