xref: /linux/drivers/pci/setup-res.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
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 	dev_dbg(&dev->dev, "BAR %d: got res %pR bus [%#llx-%#llx] "
55 		"flags %#lx\n", resno, res,
56 		 (unsigned long long)region.start,
57 		 (unsigned long long)region.end,
58 		 (unsigned long)res->flags);
59 
60 	new = region.start | (res->flags & PCI_REGION_FLAG_MASK);
61 	if (res->flags & IORESOURCE_IO)
62 		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
63 	else
64 		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
65 
66 	reg = pci_resource_bar(dev, resno, &type);
67 	if (!reg)
68 		return;
69 	if (type != pci_bar_unknown) {
70 		if (!(res->flags & IORESOURCE_ROM_ENABLE))
71 			return;
72 		new |= PCI_ROM_ADDRESS_ENABLE;
73 	}
74 
75 	pci_write_config_dword(dev, reg, new);
76 	pci_read_config_dword(dev, reg, &check);
77 
78 	if ((new ^ check) & mask) {
79 		dev_err(&dev->dev, "BAR %d: error updating (%#08x != %#08x)\n",
80 			resno, new, check);
81 	}
82 
83 	if ((new & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
84 	    (PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64)) {
85 		new = region.start >> 16 >> 16;
86 		pci_write_config_dword(dev, reg + 4, new);
87 		pci_read_config_dword(dev, reg + 4, &check);
88 		if (check != new) {
89 			dev_err(&dev->dev, "BAR %d: error updating "
90 			       "(high %#08x != %#08x)\n", resno, new, check);
91 		}
92 	}
93 	res->flags &= ~IORESOURCE_UNSET;
94 	dev_dbg(&dev->dev, "BAR %d: moved to bus [%#llx-%#llx] flags %#lx\n",
95 		resno, (unsigned long long)region.start,
96 		(unsigned long long)region.end, res->flags);
97 }
98 
99 int pci_claim_resource(struct pci_dev *dev, int resource)
100 {
101 	struct resource *res = &dev->resource[resource];
102 	struct resource *root;
103 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
104 	int err;
105 
106 	root = pci_find_parent_resource(dev, res);
107 
108 	err = -EINVAL;
109 	if (root != NULL)
110 		err = insert_resource(root, res);
111 
112 	if (err) {
113 		dev_err(&dev->dev, "BAR %d: %s of %s %pR\n",
114 			resource,
115 			root ? "address space collision on" :
116 				"no parent found for",
117 			dtype, res);
118 	}
119 
120 	return err;
121 }
122 
123 #ifdef CONFIG_PCI_QUIRKS
124 void pci_disable_bridge_window(struct pci_dev *dev)
125 {
126 	dev_dbg(&dev->dev, "Disabling bridge window.\n");
127 
128 	/* MMIO Base/Limit */
129 	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
130 
131 	/* Prefetchable MMIO Base/Limit */
132 	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
133 	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
134 	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
135 }
136 #endif	/* CONFIG_PCI_QUIRKS */
137 
138 static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
139 				 int resno)
140 {
141 	struct resource *res = dev->resource + resno;
142 	resource_size_t size, min, align;
143 	int ret;
144 
145 	size = resource_size(res);
146 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
147 	align = resource_alignment(res);
148 
149 	/* First, try exact prefetching match.. */
150 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
151 				     IORESOURCE_PREFETCH,
152 				     pcibios_align_resource, dev);
153 
154 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
155 		/*
156 		 * That failed.
157 		 *
158 		 * But a prefetching area can handle a non-prefetching
159 		 * window (it will just not perform as well).
160 		 */
161 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
162 					     pcibios_align_resource, dev);
163 	}
164 
165 	if (!ret) {
166 		res->flags &= ~IORESOURCE_STARTALIGN;
167 		if (resno < PCI_BRIDGE_RESOURCES)
168 			pci_update_resource(dev, resno);
169 	}
170 
171 	return ret;
172 }
173 
174 int pci_assign_resource(struct pci_dev *dev, int resno)
175 {
176 	struct resource *res = dev->resource + resno;
177 	resource_size_t align;
178 	struct pci_bus *bus;
179 	int ret;
180 
181 	align = resource_alignment(res);
182 	if (!align) {
183 		dev_info(&dev->dev, "BAR %d: can't allocate resource (bogus "
184 			"alignment) %pR flags %#lx\n",
185 			resno, res, res->flags);
186 		return -EINVAL;
187 	}
188 
189 	bus = dev->bus;
190 	while ((ret = __pci_assign_resource(bus, dev, resno))) {
191 		if (bus->parent && bus->self->transparent)
192 			bus = bus->parent;
193 		else
194 			bus = NULL;
195 		if (bus)
196 			continue;
197 		break;
198 	}
199 
200 	if (ret)
201 		dev_info(&dev->dev, "BAR %d: can't allocate %s resource %pR\n",
202 			resno, res->flags & IORESOURCE_IO ? "I/O" : "mem", res);
203 
204 	return ret;
205 }
206 
207 #if 0
208 int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
209 {
210 	struct pci_bus *bus = dev->bus;
211 	struct resource *res = dev->resource + resno;
212 	unsigned int type_mask;
213 	int i, ret = -EBUSY;
214 
215 	type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
216 
217 	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
218 		struct resource *r = bus->resource[i];
219 		if (!r)
220 			continue;
221 
222 		/* type_mask must match */
223 		if ((res->flags ^ r->flags) & type_mask)
224 			continue;
225 
226 		ret = request_resource(r, res);
227 
228 		if (ret == 0)
229 			break;
230 	}
231 
232 	if (ret) {
233 		dev_err(&dev->dev, "BAR %d: can't allocate %s resource %pR\n",
234 			resno, res->flags & IORESOURCE_IO ? "I/O" : "mem", res);
235 	} else if (resno < PCI_BRIDGE_RESOURCES) {
236 		pci_update_resource(dev, resno);
237 	}
238 
239 	return ret;
240 }
241 EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
242 #endif
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 = resource_alignment(r);
263 		if (!r_align) {
264 			dev_warn(&dev->dev, "BAR %d: bogus alignment "
265 				"%pR flags %#lx\n",
266 				i, r, r->flags);
267 			continue;
268 		}
269 		for (list = head; ; list = list->next) {
270 			resource_size_t align = 0;
271 			struct resource_list *ln = list->next;
272 
273 			if (ln)
274 				align = resource_alignment(ln->res);
275 
276 			if (r_align > align) {
277 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
278 				if (!tmp)
279 					panic("pdev_sort_resources(): "
280 					      "kmalloc() failed!\n");
281 				tmp->next = ln;
282 				tmp->res = r;
283 				tmp->dev = dev;
284 				list->next = tmp;
285 				break;
286 			}
287 		}
288 	}
289 }
290 
291 int pci_enable_resources(struct pci_dev *dev, int mask)
292 {
293 	u16 cmd, old_cmd;
294 	int i;
295 	struct resource *r;
296 
297 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
298 	old_cmd = cmd;
299 
300 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
301 		if (!(mask & (1 << i)))
302 			continue;
303 
304 		r = &dev->resource[i];
305 
306 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
307 			continue;
308 		if ((i == PCI_ROM_RESOURCE) &&
309 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
310 			continue;
311 
312 		if (!r->parent) {
313 			dev_err(&dev->dev, "device not available because of "
314 				"BAR %d %pR collisions\n", i, r);
315 			return -EINVAL;
316 		}
317 
318 		if (r->flags & IORESOURCE_IO)
319 			cmd |= PCI_COMMAND_IO;
320 		if (r->flags & IORESOURCE_MEM)
321 			cmd |= PCI_COMMAND_MEMORY;
322 	}
323 
324 	if (cmd != old_cmd) {
325 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
326 			 old_cmd, cmd);
327 		pci_write_config_word(dev, PCI_COMMAND, cmd);
328 	}
329 	return 0;
330 }
331