xref: /openbmc/linux/drivers/pci/setup-res.c (revision 1fa6ac37)
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 ((new & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
78 	    (PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_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 static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
133 				 int resno)
134 {
135 	struct resource *res = dev->resource + resno;
136 	resource_size_t size, min, align;
137 	int ret;
138 
139 	size = resource_size(res);
140 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
141 	align = pci_resource_alignment(dev, res);
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 
159 	if (!ret) {
160 		res->flags &= ~IORESOURCE_STARTALIGN;
161 		dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
162 		if (resno < PCI_BRIDGE_RESOURCES)
163 			pci_update_resource(dev, resno);
164 	}
165 
166 	return ret;
167 }
168 
169 int pci_assign_resource(struct pci_dev *dev, int resno)
170 {
171 	struct resource *res = dev->resource + resno;
172 	resource_size_t align;
173 	struct pci_bus *bus;
174 	int ret;
175 	char *type;
176 
177 	align = pci_resource_alignment(dev, res);
178 	if (!align) {
179 		dev_info(&dev->dev, "BAR %d: can't assign %pR "
180 			 "(bogus alignment)\n", resno, res);
181 		return -EINVAL;
182 	}
183 
184 	bus = dev->bus;
185 	while ((ret = __pci_assign_resource(bus, dev, resno))) {
186 		if (bus->parent && bus->self->transparent)
187 			bus = bus->parent;
188 		else
189 			bus = NULL;
190 		if (bus)
191 			continue;
192 		break;
193 	}
194 
195 	if (ret) {
196 		if (res->flags & IORESOURCE_MEM)
197 			if (res->flags & IORESOURCE_PREFETCH)
198 				type = "mem pref";
199 			else
200 				type = "mem";
201 		else if (res->flags & IORESOURCE_IO)
202 			type = "io";
203 		else
204 			type = "unknown";
205 		dev_info(&dev->dev,
206 			 "BAR %d: can't assign %s (size %#llx)\n",
207 			 resno, type, (unsigned long long) resource_size(res));
208 	}
209 
210 	return ret;
211 }
212 
213 /* Sort resources by alignment */
214 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
215 {
216 	int i;
217 
218 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
219 		struct resource *r;
220 		struct resource_list *list, *tmp;
221 		resource_size_t r_align;
222 
223 		r = &dev->resource[i];
224 
225 		if (r->flags & IORESOURCE_PCI_FIXED)
226 			continue;
227 
228 		if (!(r->flags) || r->parent)
229 			continue;
230 
231 		r_align = pci_resource_alignment(dev, r);
232 		if (!r_align) {
233 			dev_warn(&dev->dev, "BAR %d: %pR has bogus alignment\n",
234 				 i, r);
235 			continue;
236 		}
237 		for (list = head; ; list = list->next) {
238 			resource_size_t align = 0;
239 			struct resource_list *ln = list->next;
240 
241 			if (ln)
242 				align = pci_resource_alignment(ln->dev, ln->res);
243 
244 			if (r_align > align) {
245 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
246 				if (!tmp)
247 					panic("pdev_sort_resources(): "
248 					      "kmalloc() failed!\n");
249 				tmp->next = ln;
250 				tmp->res = r;
251 				tmp->dev = dev;
252 				list->next = tmp;
253 				break;
254 			}
255 		}
256 	}
257 }
258 
259 int pci_enable_resources(struct pci_dev *dev, int mask)
260 {
261 	u16 cmd, old_cmd;
262 	int i;
263 	struct resource *r;
264 
265 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
266 	old_cmd = cmd;
267 
268 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
269 		if (!(mask & (1 << i)))
270 			continue;
271 
272 		r = &dev->resource[i];
273 
274 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
275 			continue;
276 		if ((i == PCI_ROM_RESOURCE) &&
277 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
278 			continue;
279 
280 		if (!r->parent) {
281 			dev_err(&dev->dev, "device not available "
282 				"(can't reserve %pR)\n", r);
283 			return -EINVAL;
284 		}
285 
286 		if (r->flags & IORESOURCE_IO)
287 			cmd |= PCI_COMMAND_IO;
288 		if (r->flags & IORESOURCE_MEM)
289 			cmd |= PCI_COMMAND_MEMORY;
290 	}
291 
292 	if (cmd != old_cmd) {
293 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
294 			 old_cmd, cmd);
295 		pci_write_config_word(dev, PCI_COMMAND, cmd);
296 	}
297 	return 0;
298 }
299