xref: /linux/drivers/pci/setup-res.c (revision 040932cdcfca9b0ac55a4f74f194c2e2c8a2527b)
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 	int err;
104 
105 	root = pci_find_parent_resource(dev, res);
106 
107 	err = -EINVAL;
108 	if (root != NULL)
109 		err = request_resource(root, res);
110 
111 	if (err) {
112 		const char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
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 EXPORT_SYMBOL(pci_claim_resource);
123 
124 #ifdef CONFIG_PCI_QUIRKS
125 void pci_disable_bridge_window(struct pci_dev *dev)
126 {
127 	dev_dbg(&dev->dev, "Disabling bridge window.\n");
128 
129 	/* MMIO Base/Limit */
130 	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
131 
132 	/* Prefetchable MMIO Base/Limit */
133 	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
134 	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
135 	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
136 }
137 #endif	/* CONFIG_PCI_QUIRKS */
138 
139 static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
140 				 int resno)
141 {
142 	struct resource *res = dev->resource + resno;
143 	resource_size_t size, min, align;
144 	int ret;
145 
146 	size = resource_size(res);
147 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
148 	align = pci_resource_alignment(dev, res);
149 
150 	/* First, try exact prefetching match.. */
151 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
152 				     IORESOURCE_PREFETCH,
153 				     pcibios_align_resource, dev);
154 
155 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
156 		/*
157 		 * That failed.
158 		 *
159 		 * But a prefetching area can handle a non-prefetching
160 		 * window (it will just not perform as well).
161 		 */
162 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
163 					     pcibios_align_resource, dev);
164 	}
165 
166 	if (!ret) {
167 		res->flags &= ~IORESOURCE_STARTALIGN;
168 		if (resno < PCI_BRIDGE_RESOURCES)
169 			pci_update_resource(dev, resno);
170 	}
171 
172 	return ret;
173 }
174 
175 int pci_assign_resource(struct pci_dev *dev, int resno)
176 {
177 	struct resource *res = dev->resource + resno;
178 	resource_size_t align;
179 	struct pci_bus *bus;
180 	int ret;
181 
182 	align = pci_resource_alignment(dev, res);
183 	if (!align) {
184 		dev_info(&dev->dev, "BAR %d: can't allocate resource (bogus "
185 			"alignment) %pR flags %#lx\n",
186 			resno, res, res->flags);
187 		return -EINVAL;
188 	}
189 
190 	bus = dev->bus;
191 	while ((ret = __pci_assign_resource(bus, dev, resno))) {
192 		if (bus->parent && bus->self->transparent)
193 			bus = bus->parent;
194 		else
195 			bus = NULL;
196 		if (bus)
197 			continue;
198 		break;
199 	}
200 
201 	if (ret)
202 		dev_info(&dev->dev, "BAR %d: can't allocate %s resource %pR\n",
203 			resno, res->flags & IORESOURCE_IO ? "I/O" : "mem", res);
204 
205 	return ret;
206 }
207 
208 #if 0
209 int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
210 {
211 	struct pci_bus *bus = dev->bus;
212 	struct resource *res = dev->resource + resno;
213 	unsigned int type_mask;
214 	int i, ret = -EBUSY;
215 
216 	type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
217 
218 	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
219 		struct resource *r = bus->resource[i];
220 		if (!r)
221 			continue;
222 
223 		/* type_mask must match */
224 		if ((res->flags ^ r->flags) & type_mask)
225 			continue;
226 
227 		ret = request_resource(r, res);
228 
229 		if (ret == 0)
230 			break;
231 	}
232 
233 	if (ret) {
234 		dev_err(&dev->dev, "BAR %d: can't allocate %s resource %pR\n",
235 			resno, res->flags & IORESOURCE_IO ? "I/O" : "mem", res);
236 	} else if (resno < PCI_BRIDGE_RESOURCES) {
237 		pci_update_resource(dev, resno);
238 	}
239 
240 	return ret;
241 }
242 EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
243 #endif
244 
245 /* Sort resources by alignment */
246 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
247 {
248 	int i;
249 
250 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
251 		struct resource *r;
252 		struct resource_list *list, *tmp;
253 		resource_size_t r_align;
254 
255 		r = &dev->resource[i];
256 
257 		if (r->flags & IORESOURCE_PCI_FIXED)
258 			continue;
259 
260 		if (!(r->flags) || r->parent)
261 			continue;
262 
263 		r_align = pci_resource_alignment(dev, r);
264 		if (!r_align) {
265 			dev_warn(&dev->dev, "BAR %d: bogus alignment "
266 				"%pR flags %#lx\n",
267 				i, r, r->flags);
268 			continue;
269 		}
270 		for (list = head; ; list = list->next) {
271 			resource_size_t align = 0;
272 			struct resource_list *ln = list->next;
273 
274 			if (ln)
275 				align = pci_resource_alignment(ln->dev, ln->res);
276 
277 			if (r_align > align) {
278 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
279 				if (!tmp)
280 					panic("pdev_sort_resources(): "
281 					      "kmalloc() failed!\n");
282 				tmp->next = ln;
283 				tmp->res = r;
284 				tmp->dev = dev;
285 				list->next = tmp;
286 				break;
287 			}
288 		}
289 	}
290 }
291 
292 int pci_enable_resources(struct pci_dev *dev, int mask)
293 {
294 	u16 cmd, old_cmd;
295 	int i;
296 	struct resource *r;
297 
298 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
299 	old_cmd = cmd;
300 
301 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
302 		if (!(mask & (1 << i)))
303 			continue;
304 
305 		r = &dev->resource[i];
306 
307 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
308 			continue;
309 		if ((i == PCI_ROM_RESOURCE) &&
310 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
311 			continue;
312 
313 		if (!r->parent) {
314 			dev_err(&dev->dev, "device not available because of "
315 				"BAR %d %pR collisions\n", i, r);
316 			return -EINVAL;
317 		}
318 
319 		if (r->flags & IORESOURCE_IO)
320 			cmd |= PCI_COMMAND_IO;
321 		if (r->flags & IORESOURCE_MEM)
322 			cmd |= PCI_COMMAND_MEMORY;
323 	}
324 
325 	if (cmd != old_cmd) {
326 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
327 			 old_cmd, cmd);
328 		pci_write_config_word(dev, PCI_COMMAND, cmd);
329 	}
330 	return 0;
331 }
332