xref: /openbmc/linux/drivers/pci/setup-res.c (revision 384740dc)
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, struct resource *res, int resno)
30 {
31 	struct pci_bus_region region;
32 	u32 new, check, mask;
33 	int reg;
34 
35 	/*
36 	 * Ignore resources for unimplemented BARs and unused resource slots
37 	 * for 64 bit BARs.
38 	 */
39 	if (!res->flags)
40 		return;
41 
42 	/*
43 	 * Ignore non-moveable resources.  This might be legacy resources for
44 	 * which no functional BAR register exists or another important
45 	 * system resource we shouldn't move around.
46 	 */
47 	if (res->flags & IORESOURCE_PCI_FIXED)
48 		return;
49 
50 	pcibios_resource_to_bus(dev, &region, res);
51 
52 	dev_dbg(&dev->dev, "BAR %d: got res [%#llx-%#llx] bus [%#llx-%#llx] "
53 		"flags %#lx\n", resno,
54 		 (unsigned long long)res->start,
55 		 (unsigned long long)res->end,
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 	if (resno < 6) {
67 		reg = PCI_BASE_ADDRESS_0 + 4 * resno;
68 	} else if (resno == PCI_ROM_RESOURCE) {
69 		if (!(res->flags & IORESOURCE_ROM_ENABLE))
70 			return;
71 		new |= PCI_ROM_ADDRESS_ENABLE;
72 		reg = dev->rom_base_reg;
73 	} else {
74 		/* Hmm, non-standard resource. */
75 
76 		return;		/* kill uninitialised var warning */
77 	}
78 
79 	pci_write_config_dword(dev, reg, new);
80 	pci_read_config_dword(dev, reg, &check);
81 
82 	if ((new ^ check) & mask) {
83 		dev_err(&dev->dev, "BAR %d: error updating (%#08x != %#08x)\n",
84 			resno, new, check);
85 	}
86 
87 	if ((new & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
88 	    (PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64)) {
89 		new = region.start >> 16 >> 16;
90 		pci_write_config_dword(dev, reg + 4, new);
91 		pci_read_config_dword(dev, reg + 4, &check);
92 		if (check != new) {
93 			dev_err(&dev->dev, "BAR %d: error updating "
94 			       "(high %#08x != %#08x)\n", resno, new, check);
95 		}
96 	}
97 	res->flags &= ~IORESOURCE_UNSET;
98 	dev_dbg(&dev->dev, "BAR %d: moved to bus [%#llx-%#llx] flags %#lx\n",
99 		resno, (unsigned long long)region.start,
100 		(unsigned long long)region.end, res->flags);
101 }
102 
103 int pci_claim_resource(struct pci_dev *dev, int resource)
104 {
105 	struct resource *res = &dev->resource[resource];
106 	struct resource *root = NULL;
107 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
108 	int err;
109 
110 	root = pcibios_select_root(dev, res);
111 
112 	err = -EINVAL;
113 	if (root != NULL)
114 		err = insert_resource(root, res);
115 
116 	if (err) {
117 		dev_err(&dev->dev, "BAR %d: %s of %s [%#llx-%#llx]\n",
118 			resource,
119 			root ? "address space collision on" :
120 				"no parent found for",
121 			dtype,
122 			(unsigned long long)res->start,
123 			(unsigned long long)res->end);
124 	}
125 
126 	return err;
127 }
128 
129 int pci_assign_resource(struct pci_dev *dev, int resno)
130 {
131 	struct pci_bus *bus = dev->bus;
132 	struct resource *res = dev->resource + resno;
133 	resource_size_t size, min, align;
134 	int ret;
135 
136 	size = res->end - res->start + 1;
137 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
138 
139 	align = resource_alignment(res);
140 	if (!align) {
141 		dev_err(&dev->dev, "BAR %d: can't allocate resource (bogus "
142 			"alignment) [%#llx-%#llx] flags %#lx\n",
143 			resno, (unsigned long long)res->start,
144 			(unsigned long long)res->end, res->flags);
145 		return -EINVAL;
146 	}
147 
148 	/* First, try exact prefetching match.. */
149 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
150 				     IORESOURCE_PREFETCH,
151 				     pcibios_align_resource, dev);
152 
153 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
154 		/*
155 		 * That failed.
156 		 *
157 		 * But a prefetching area can handle a non-prefetching
158 		 * window (it will just not perform as well).
159 		 */
160 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
161 					     pcibios_align_resource, dev);
162 	}
163 
164 	if (ret) {
165 		dev_err(&dev->dev, "BAR %d: can't allocate %s resource "
166 			"[%#llx-%#llx]\n", resno,
167 			res->flags & IORESOURCE_IO ? "I/O" : "mem",
168 			(unsigned long long)res->start,
169 			(unsigned long long)res->end);
170 	} else {
171 		res->flags &= ~IORESOURCE_STARTALIGN;
172 		if (resno < PCI_BRIDGE_RESOURCES)
173 			pci_update_resource(dev, res, resno);
174 	}
175 
176 	return ret;
177 }
178 
179 #if 0
180 int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
181 {
182 	struct pci_bus *bus = dev->bus;
183 	struct resource *res = dev->resource + resno;
184 	unsigned int type_mask;
185 	int i, ret = -EBUSY;
186 
187 	type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
188 
189 	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
190 		struct resource *r = bus->resource[i];
191 		if (!r)
192 			continue;
193 
194 		/* type_mask must match */
195 		if ((res->flags ^ r->flags) & type_mask)
196 			continue;
197 
198 		ret = request_resource(r, res);
199 
200 		if (ret == 0)
201 			break;
202 	}
203 
204 	if (ret) {
205 		dev_err(&dev->dev, "BAR %d: can't allocate %s resource "
206 			"[%#llx-%#llx\n]", resno,
207 			res->flags & IORESOURCE_IO ? "I/O" : "mem",
208 			(unsigned long long)res->start,
209 			(unsigned long long)res->end);
210 	} else if (resno < PCI_BRIDGE_RESOURCES) {
211 		pci_update_resource(dev, res, resno);
212 	}
213 
214 	return ret;
215 }
216 EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
217 #endif
218 
219 /* Sort resources by alignment */
220 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
221 {
222 	int i;
223 
224 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
225 		struct resource *r;
226 		struct resource_list *list, *tmp;
227 		resource_size_t r_align;
228 
229 		r = &dev->resource[i];
230 
231 		if (r->flags & IORESOURCE_PCI_FIXED)
232 			continue;
233 
234 		if (!(r->flags) || r->parent)
235 			continue;
236 
237 		r_align = resource_alignment(r);
238 		if (!r_align) {
239 			dev_warn(&dev->dev, "BAR %d: bogus alignment "
240 				"[%#llx-%#llx] flags %#lx\n",
241 				i, (unsigned long long)r->start,
242 				(unsigned long long)r->end, r->flags);
243 			continue;
244 		}
245 		for (list = head; ; list = list->next) {
246 			resource_size_t align = 0;
247 			struct resource_list *ln = list->next;
248 
249 			if (ln)
250 				align = resource_alignment(ln->res);
251 
252 			if (r_align > align) {
253 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
254 				if (!tmp)
255 					panic("pdev_sort_resources(): "
256 					      "kmalloc() failed!\n");
257 				tmp->next = ln;
258 				tmp->res = r;
259 				tmp->dev = dev;
260 				list->next = tmp;
261 				break;
262 			}
263 		}
264 	}
265 }
266 
267 int pci_enable_resources(struct pci_dev *dev, int mask)
268 {
269 	u16 cmd, old_cmd;
270 	int i;
271 	struct resource *r;
272 
273 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
274 	old_cmd = cmd;
275 
276 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
277 		if (!(mask & (1 << i)))
278 			continue;
279 
280 		r = &dev->resource[i];
281 
282 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
283 			continue;
284 		if ((i == PCI_ROM_RESOURCE) &&
285 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
286 			continue;
287 
288 		if (!r->parent) {
289 			dev_err(&dev->dev, "device not available because of "
290 				"BAR %d [%#llx-%#llx] collisions\n", i,
291 				(unsigned long long) r->start,
292 				(unsigned long long) r->end);
293 			return -EINVAL;
294 		}
295 
296 		if (r->flags & IORESOURCE_IO)
297 			cmd |= PCI_COMMAND_IO;
298 		if (r->flags & IORESOURCE_MEM)
299 			cmd |= PCI_COMMAND_MEMORY;
300 	}
301 
302 	if (cmd != old_cmd) {
303 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
304 			 old_cmd, cmd);
305 		pci_write_config_word(dev, PCI_COMMAND, cmd);
306 	}
307 	return 0;
308 }
309