xref: /linux/drivers/pci/setup-res.c (revision f7511d5f66f01fc451747b24e79f3ada7a3af9af)
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
30 pci_update_resource(struct pci_dev *dev, struct resource *res, int resno)
31 {
32 	struct pci_bus_region region;
33 	u32 new, check, mask;
34 	int reg;
35 
36 	/*
37 	 * Ignore resources for unimplemented BARs and unused resource slots
38 	 * for 64 bit BARs.
39 	 */
40 	if (!res->flags)
41 		return;
42 
43 	/*
44 	 * Ignore non-moveable resources.  This might be legacy resources for
45 	 * which no functional BAR register exists or another important
46 	 * system resource we should better not move around in system address
47 	 * space.
48 	 */
49 	if (res->flags & IORESOURCE_PCI_FIXED)
50 		return;
51 
52 	pcibios_resource_to_bus(dev, &region, res);
53 
54 	pr_debug("  got res [%llx:%llx] bus [%llx:%llx] flags %lx for "
55 		 "BAR %d of %s\n", (unsigned long long)res->start,
56 		 (unsigned long long)res->end,
57 		 (unsigned long long)region.start,
58 		 (unsigned long long)region.end,
59 		 (unsigned long)res->flags, resno, pci_name(dev));
60 
61 	new = region.start | (res->flags & PCI_REGION_FLAG_MASK);
62 	if (res->flags & IORESOURCE_IO)
63 		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
64 	else
65 		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
66 
67 	if (resno < 6) {
68 		reg = PCI_BASE_ADDRESS_0 + 4 * resno;
69 	} else if (resno == PCI_ROM_RESOURCE) {
70 		if (!(res->flags & IORESOURCE_ROM_ENABLE))
71 			return;
72 		new |= PCI_ROM_ADDRESS_ENABLE;
73 		reg = dev->rom_base_reg;
74 	} else {
75 		/* Hmm, non-standard resource. */
76 
77 		return;		/* kill uninitialised var warning */
78 	}
79 
80 	pci_write_config_dword(dev, reg, new);
81 	pci_read_config_dword(dev, reg, &check);
82 
83 	if ((new ^ check) & mask) {
84 		printk(KERN_ERR "PCI: Error while updating region "
85 		       "%s/%d (%08x != %08x)\n", pci_name(dev), resno,
86 		       new, check);
87 	}
88 
89 	if ((new & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
90 	    (PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64)) {
91 		new = region.start >> 16 >> 16;
92 		pci_write_config_dword(dev, reg + 4, new);
93 		pci_read_config_dword(dev, reg + 4, &check);
94 		if (check != new) {
95 			printk(KERN_ERR "PCI: Error updating region "
96 			       "%s/%d (high %08x != %08x)\n",
97 			       pci_name(dev), resno, new, check);
98 		}
99 	}
100 	res->flags &= ~IORESOURCE_UNSET;
101 	pr_debug("PCI: moved device %s resource %d (%lx) to %x\n",
102 		pci_name(dev), resno, res->flags,
103 		new & ~PCI_REGION_FLAG_MASK);
104 }
105 
106 int pci_claim_resource(struct pci_dev *dev, int resource)
107 {
108 	struct resource *res = &dev->resource[resource];
109 	struct resource *root = NULL;
110 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
111 	int err;
112 
113 	root = pcibios_select_root(dev, res);
114 
115 	err = -EINVAL;
116 	if (root != NULL)
117 		err = insert_resource(root, res);
118 
119 	if (err) {
120 		printk(KERN_ERR "PCI: %s region %d of %s %s [%llx:%llx]\n",
121 			root ? "Address space collision on" :
122 				"No parent found for",
123 			resource, dtype, pci_name(dev),
124 			(unsigned long long)res->start,
125 			(unsigned long long)res->end);
126 	}
127 
128 	return err;
129 }
130 
131 int pci_assign_resource(struct pci_dev *dev, int resno)
132 {
133 	struct pci_bus *bus = dev->bus;
134 	struct resource *res = dev->resource + resno;
135 	resource_size_t size, min, align;
136 	int ret;
137 
138 	size = res->end - res->start + 1;
139 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
140 
141 	align = resource_alignment(res);
142 	if (!align) {
143 		printk(KERN_ERR "PCI: Cannot allocate resource (bogus "
144 			"alignment) %d [%llx:%llx] (flags %lx) of %s\n",
145 			resno, (unsigned long long)res->start,
146 			(unsigned long long)res->end, res->flags,
147 			pci_name(dev));
148 		return -EINVAL;
149 	}
150 
151 	/* First, try exact prefetching match.. */
152 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
153 				     IORESOURCE_PREFETCH,
154 				     pcibios_align_resource, dev);
155 
156 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
157 		/*
158 		 * That failed.
159 		 *
160 		 * But a prefetching area can handle a non-prefetching
161 		 * window (it will just not perform as well).
162 		 */
163 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
164 					     pcibios_align_resource, dev);
165 	}
166 
167 	if (ret) {
168 		printk(KERN_ERR "PCI: Failed to allocate %s resource "
169 			"#%d:%llx@%llx for %s\n",
170 			res->flags & IORESOURCE_IO ? "I/O" : "mem",
171 			resno, (unsigned long long)size,
172 			(unsigned long long)res->start, pci_name(dev));
173 	} else {
174 		res->flags &= ~IORESOURCE_STARTALIGN;
175 		if (resno < PCI_BRIDGE_RESOURCES)
176 			pci_update_resource(dev, res, resno);
177 	}
178 
179 	return ret;
180 }
181 
182 #if 0
183 int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
184 {
185 	struct pci_bus *bus = dev->bus;
186 	struct resource *res = dev->resource + resno;
187 	unsigned int type_mask;
188 	int i, ret = -EBUSY;
189 
190 	type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
191 
192 	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
193 		struct resource *r = bus->resource[i];
194 		if (!r)
195 			continue;
196 
197 		/* type_mask must match */
198 		if ((res->flags ^ r->flags) & type_mask)
199 			continue;
200 
201 		ret = request_resource(r, res);
202 
203 		if (ret == 0)
204 			break;
205 	}
206 
207 	if (ret) {
208 		printk(KERN_ERR "PCI: Failed to allocate %s resource "
209 				"#%d:%llx@%llx for %s\n",
210 			res->flags & IORESOURCE_IO ? "I/O" : "mem",
211 			resno, (unsigned long long)(res->end - res->start + 1),
212 			(unsigned long long)res->start, pci_name(dev));
213 	} else if (resno < PCI_BRIDGE_RESOURCES) {
214 		pci_update_resource(dev, res, resno);
215 	}
216 
217 	return ret;
218 }
219 EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
220 #endif
221 
222 /* Sort resources by alignment */
223 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
224 {
225 	int i;
226 
227 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
228 		struct resource *r;
229 		struct resource_list *list, *tmp;
230 		resource_size_t r_align;
231 
232 		r = &dev->resource[i];
233 
234 		if (r->flags & IORESOURCE_PCI_FIXED)
235 			continue;
236 
237 		if (!(r->flags) || r->parent)
238 			continue;
239 
240 		r_align = resource_alignment(r);
241 		if (!r_align) {
242 			printk(KERN_WARNING "PCI: bogus alignment of resource "
243 				"%d [%llx:%llx] (flags %lx) of %s\n",
244 				i, (unsigned long long)r->start,
245 				(unsigned long long)r->end, r->flags,
246 				pci_name(dev));
247 			continue;
248 		}
249 		for (list = head; ; list = list->next) {
250 			resource_size_t align = 0;
251 			struct resource_list *ln = list->next;
252 
253 			if (ln)
254 				align = resource_alignment(ln->res);
255 
256 			if (r_align > align) {
257 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
258 				if (!tmp)
259 					panic("pdev_sort_resources(): "
260 					      "kmalloc() failed!\n");
261 				tmp->next = ln;
262 				tmp->res = r;
263 				tmp->dev = dev;
264 				list->next = tmp;
265 				break;
266 			}
267 		}
268 	}
269 }
270 
271 int pci_enable_resources(struct pci_dev *dev, int mask)
272 {
273 	u16 cmd, old_cmd;
274 	int i;
275 	struct resource *r;
276 
277 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
278 	old_cmd = cmd;
279 
280 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
281 		if (!(mask & (1 << i)))
282 			continue;
283 
284 		r = &dev->resource[i];
285 
286 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
287 			continue;
288 		if ((i == PCI_ROM_RESOURCE) &&
289 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
290 			continue;
291 
292 		if (!r->parent) {
293 			dev_err(&dev->dev, "device not available because of "
294 				"BAR %d [%llx:%llx] collisions\n", i,
295 				(unsigned long long) r->start,
296 				(unsigned long long) r->end);
297 			return -EINVAL;
298 		}
299 
300 		if (r->flags & IORESOURCE_IO)
301 			cmd |= PCI_COMMAND_IO;
302 		if (r->flags & IORESOURCE_MEM)
303 			cmd |= PCI_COMMAND_MEMORY;
304 	}
305 
306 	if (cmd != old_cmd) {
307 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
308 			 old_cmd, cmd);
309 		pci_write_config_word(dev, PCI_COMMAND, cmd);
310 	}
311 	return 0;
312 }
313