xref: /linux/drivers/pci/setup-res.c (revision 2c1ba398ac9da3305815f6ae8e95ae2b9fd3b5ff)
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/pci.h>
22 #include <linux/errno.h>
23 #include <linux/ioport.h>
24 #include <linux/cache.h>
25 #include <linux/slab.h>
26 #include "pci.h"
27 
28 
29 void pci_update_resource(struct pci_dev *dev, int resno)
30 {
31 	struct pci_bus_region region;
32 	u32 new, check, mask;
33 	int reg;
34 	enum pci_bar_type type;
35 	struct resource *res = dev->resource + resno;
36 
37 	/*
38 	 * Ignore resources for unimplemented BARs and unused resource slots
39 	 * for 64 bit BARs.
40 	 */
41 	if (!res->flags)
42 		return;
43 
44 	/*
45 	 * Ignore non-moveable resources.  This might be legacy resources for
46 	 * which no functional BAR register exists or another important
47 	 * system resource we shouldn't move around.
48 	 */
49 	if (res->flags & IORESOURCE_PCI_FIXED)
50 		return;
51 
52 	pcibios_resource_to_bus(dev, &region, res);
53 
54 	new = region.start | (res->flags & PCI_REGION_FLAG_MASK);
55 	if (res->flags & IORESOURCE_IO)
56 		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
57 	else
58 		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
59 
60 	reg = pci_resource_bar(dev, resno, &type);
61 	if (!reg)
62 		return;
63 	if (type != pci_bar_unknown) {
64 		if (!(res->flags & IORESOURCE_ROM_ENABLE))
65 			return;
66 		new |= PCI_ROM_ADDRESS_ENABLE;
67 	}
68 
69 	pci_write_config_dword(dev, reg, new);
70 	pci_read_config_dword(dev, reg, &check);
71 
72 	if ((new ^ check) & mask) {
73 		dev_err(&dev->dev, "BAR %d: error updating (%#08x != %#08x)\n",
74 			resno, new, check);
75 	}
76 
77 	if (res->flags & IORESOURCE_MEM_64) {
78 		new = region.start >> 16 >> 16;
79 		pci_write_config_dword(dev, reg + 4, new);
80 		pci_read_config_dword(dev, reg + 4, &check);
81 		if (check != new) {
82 			dev_err(&dev->dev, "BAR %d: error updating "
83 			       "(high %#08x != %#08x)\n", resno, new, check);
84 		}
85 	}
86 	res->flags &= ~IORESOURCE_UNSET;
87 	dev_info(&dev->dev, "BAR %d: set to %pR (PCI address [%#llx-%#llx])\n",
88 		 resno, res, (unsigned long long)region.start,
89 		 (unsigned long long)region.end);
90 }
91 
92 int pci_claim_resource(struct pci_dev *dev, int resource)
93 {
94 	struct resource *res = &dev->resource[resource];
95 	struct resource *root, *conflict;
96 
97 	root = pci_find_parent_resource(dev, res);
98 	if (!root) {
99 		dev_info(&dev->dev, "no compatible bridge window for %pR\n",
100 			 res);
101 		return -EINVAL;
102 	}
103 
104 	conflict = request_resource_conflict(root, res);
105 	if (conflict) {
106 		dev_info(&dev->dev,
107 			 "address space collision: %pR conflicts with %s %pR\n",
108 			 res, conflict->name, conflict);
109 		return -EBUSY;
110 	}
111 
112 	return 0;
113 }
114 EXPORT_SYMBOL(pci_claim_resource);
115 
116 #ifdef CONFIG_PCI_QUIRKS
117 void pci_disable_bridge_window(struct pci_dev *dev)
118 {
119 	dev_info(&dev->dev, "disabling bridge mem windows\n");
120 
121 	/* MMIO Base/Limit */
122 	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
123 
124 	/* Prefetchable MMIO Base/Limit */
125 	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
126 	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
127 	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
128 }
129 #endif	/* CONFIG_PCI_QUIRKS */
130 
131 static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
132 				 int resno)
133 {
134 	struct resource *res = dev->resource + resno;
135 	resource_size_t size, min, align;
136 	int ret;
137 
138 	size = resource_size(res);
139 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
140 	align = pci_resource_alignment(dev, res);
141 
142 	/* First, try exact prefetching match.. */
143 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
144 				     IORESOURCE_PREFETCH,
145 				     pcibios_align_resource, dev);
146 
147 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
148 		/*
149 		 * That failed.
150 		 *
151 		 * But a prefetching area can handle a non-prefetching
152 		 * window (it will just not perform as well).
153 		 */
154 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
155 					     pcibios_align_resource, dev);
156 	}
157 
158 	if (ret < 0 && dev->fw_addr[resno]) {
159 		struct resource *root, *conflict;
160 		resource_size_t start, end;
161 
162 		/*
163 		 * If we failed to assign anything, let's try the address
164 		 * where firmware left it.  That at least has a chance of
165 		 * working, which is better than just leaving it disabled.
166 		 */
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 		} else
187 			ret = 0;
188 	}
189 
190 	if (!ret) {
191 		res->flags &= ~IORESOURCE_STARTALIGN;
192 		dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
193 		if (resno < PCI_BRIDGE_RESOURCES)
194 			pci_update_resource(dev, resno);
195 	}
196 
197 	return ret;
198 }
199 
200 int pci_assign_resource(struct pci_dev *dev, int resno)
201 {
202 	struct resource *res = dev->resource + resno;
203 	resource_size_t align;
204 	struct pci_bus *bus;
205 	int ret;
206 	char *type;
207 
208 	align = pci_resource_alignment(dev, res);
209 	if (!align) {
210 		dev_info(&dev->dev, "BAR %d: can't assign %pR "
211 			 "(bogus alignment)\n", resno, res);
212 		return -EINVAL;
213 	}
214 
215 	bus = dev->bus;
216 	while ((ret = __pci_assign_resource(bus, dev, resno))) {
217 		if (bus->parent && bus->self->transparent)
218 			bus = bus->parent;
219 		else
220 			bus = NULL;
221 		if (bus)
222 			continue;
223 		break;
224 	}
225 
226 	if (ret) {
227 		if (res->flags & IORESOURCE_MEM)
228 			if (res->flags & IORESOURCE_PREFETCH)
229 				type = "mem pref";
230 			else
231 				type = "mem";
232 		else if (res->flags & IORESOURCE_IO)
233 			type = "io";
234 		else
235 			type = "unknown";
236 		dev_info(&dev->dev,
237 			 "BAR %d: can't assign %s (size %#llx)\n",
238 			 resno, type, (unsigned long long) resource_size(res));
239 	}
240 
241 	return ret;
242 }
243 
244 /* Sort resources by alignment */
245 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
246 {
247 	int i;
248 
249 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
250 		struct resource *r;
251 		struct resource_list *list, *tmp;
252 		resource_size_t r_align;
253 
254 		r = &dev->resource[i];
255 
256 		if (r->flags & IORESOURCE_PCI_FIXED)
257 			continue;
258 
259 		if (!(r->flags) || r->parent)
260 			continue;
261 
262 		r_align = pci_resource_alignment(dev, r);
263 		if (!r_align) {
264 			dev_warn(&dev->dev, "BAR %d: %pR has bogus alignment\n",
265 				 i, r);
266 			continue;
267 		}
268 		for (list = head; ; list = list->next) {
269 			resource_size_t align = 0;
270 			struct resource_list *ln = list->next;
271 
272 			if (ln)
273 				align = pci_resource_alignment(ln->dev, ln->res);
274 
275 			if (r_align > align) {
276 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
277 				if (!tmp)
278 					panic("pdev_sort_resources(): "
279 					      "kmalloc() failed!\n");
280 				tmp->next = ln;
281 				tmp->res = r;
282 				tmp->dev = dev;
283 				list->next = tmp;
284 				break;
285 			}
286 		}
287 	}
288 }
289 
290 int pci_enable_resources(struct pci_dev *dev, int mask)
291 {
292 	u16 cmd, old_cmd;
293 	int i;
294 	struct resource *r;
295 
296 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
297 	old_cmd = cmd;
298 
299 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
300 		if (!(mask & (1 << i)))
301 			continue;
302 
303 		r = &dev->resource[i];
304 
305 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
306 			continue;
307 		if ((i == PCI_ROM_RESOURCE) &&
308 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
309 			continue;
310 
311 		if (!r->parent) {
312 			dev_err(&dev->dev, "device not available "
313 				"(can't reserve %pR)\n", r);
314 			return -EINVAL;
315 		}
316 
317 		if (r->flags & IORESOURCE_IO)
318 			cmd |= PCI_COMMAND_IO;
319 		if (r->flags & IORESOURCE_MEM)
320 			cmd |= PCI_COMMAND_MEMORY;
321 	}
322 
323 	if (cmd != old_cmd) {
324 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
325 			 old_cmd, cmd);
326 		pci_write_config_word(dev, PCI_COMMAND, cmd);
327 	}
328 	return 0;
329 }
330