xref: /openbmc/linux/drivers/pci/setup-res.c (revision a09d2831)
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;
97 	int err;
98 
99 	root = pci_find_parent_resource(dev, res);
100 	if (!root) {
101 		dev_err(&dev->dev, "no compatible bridge window for %pR\n",
102 			res);
103 		return -EINVAL;
104 	}
105 
106 	err = request_resource(root, res);
107 	if (err)
108 		dev_err(&dev->dev,
109 			"address space collision: %pR already in use\n", res);
110 
111 	return err;
112 }
113 EXPORT_SYMBOL(pci_claim_resource);
114 
115 #ifdef CONFIG_PCI_QUIRKS
116 void pci_disable_bridge_window(struct pci_dev *dev)
117 {
118 	dev_info(&dev->dev, "disabling bridge mem windows\n");
119 
120 	/* MMIO Base/Limit */
121 	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
122 
123 	/* Prefetchable MMIO Base/Limit */
124 	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
125 	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
126 	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
127 }
128 #endif	/* CONFIG_PCI_QUIRKS */
129 
130 static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
131 				 int resno)
132 {
133 	struct resource *res = dev->resource + resno;
134 	resource_size_t size, min, align;
135 	int ret;
136 
137 	size = resource_size(res);
138 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
139 	align = pci_resource_alignment(dev, res);
140 
141 	/* First, try exact prefetching match.. */
142 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
143 				     IORESOURCE_PREFETCH,
144 				     pcibios_align_resource, dev);
145 
146 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
147 		/*
148 		 * That failed.
149 		 *
150 		 * But a prefetching area can handle a non-prefetching
151 		 * window (it will just not perform as well).
152 		 */
153 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
154 					     pcibios_align_resource, dev);
155 	}
156 
157 	if (!ret) {
158 		res->flags &= ~IORESOURCE_STARTALIGN;
159 		dev_info(&dev->dev, "BAR %d: assigned %pR\n", resno, res);
160 		if (resno < PCI_BRIDGE_RESOURCES)
161 			pci_update_resource(dev, resno);
162 	}
163 
164 	return ret;
165 }
166 
167 int pci_assign_resource(struct pci_dev *dev, int resno)
168 {
169 	struct resource *res = dev->resource + resno;
170 	resource_size_t align;
171 	struct pci_bus *bus;
172 	int ret;
173 	char *type;
174 
175 	align = pci_resource_alignment(dev, res);
176 	if (!align) {
177 		dev_info(&dev->dev, "BAR %d: can't assign %pR "
178 			 "(bogus alignment)\n", resno, res);
179 		return -EINVAL;
180 	}
181 
182 	bus = dev->bus;
183 	while ((ret = __pci_assign_resource(bus, dev, resno))) {
184 		if (bus->parent && bus->self->transparent)
185 			bus = bus->parent;
186 		else
187 			bus = NULL;
188 		if (bus)
189 			continue;
190 		break;
191 	}
192 
193 	if (ret) {
194 		if (res->flags & IORESOURCE_MEM)
195 			if (res->flags & IORESOURCE_PREFETCH)
196 				type = "mem pref";
197 			else
198 				type = "mem";
199 		else if (res->flags & IORESOURCE_IO)
200 			type = "io";
201 		else
202 			type = "unknown";
203 		dev_info(&dev->dev,
204 			 "BAR %d: can't assign %s (size %#llx)\n",
205 			 resno, type, (unsigned long long) resource_size(res));
206 	}
207 
208 	return ret;
209 }
210 
211 /* Sort resources by alignment */
212 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
213 {
214 	int i;
215 
216 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
217 		struct resource *r;
218 		struct resource_list *list, *tmp;
219 		resource_size_t r_align;
220 
221 		r = &dev->resource[i];
222 
223 		if (r->flags & IORESOURCE_PCI_FIXED)
224 			continue;
225 
226 		if (!(r->flags) || r->parent)
227 			continue;
228 
229 		r_align = pci_resource_alignment(dev, r);
230 		if (!r_align) {
231 			dev_warn(&dev->dev, "BAR %d: %pR has bogus alignment\n",
232 				 i, r);
233 			continue;
234 		}
235 		for (list = head; ; list = list->next) {
236 			resource_size_t align = 0;
237 			struct resource_list *ln = list->next;
238 
239 			if (ln)
240 				align = pci_resource_alignment(ln->dev, ln->res);
241 
242 			if (r_align > align) {
243 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
244 				if (!tmp)
245 					panic("pdev_sort_resources(): "
246 					      "kmalloc() failed!\n");
247 				tmp->next = ln;
248 				tmp->res = r;
249 				tmp->dev = dev;
250 				list->next = tmp;
251 				break;
252 			}
253 		}
254 	}
255 }
256 
257 int pci_enable_resources(struct pci_dev *dev, int mask)
258 {
259 	u16 cmd, old_cmd;
260 	int i;
261 	struct resource *r;
262 
263 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
264 	old_cmd = cmd;
265 
266 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
267 		if (!(mask & (1 << i)))
268 			continue;
269 
270 		r = &dev->resource[i];
271 
272 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
273 			continue;
274 		if ((i == PCI_ROM_RESOURCE) &&
275 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
276 			continue;
277 
278 		if (!r->parent) {
279 			dev_err(&dev->dev, "device not available "
280 				"(can't reserve %pR)\n", r);
281 			return -EINVAL;
282 		}
283 
284 		if (r->flags & IORESOURCE_IO)
285 			cmd |= PCI_COMMAND_IO;
286 		if (r->flags & IORESOURCE_MEM)
287 			cmd |= PCI_COMMAND_MEMORY;
288 	}
289 
290 	if (cmd != old_cmd) {
291 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
292 			 old_cmd, cmd);
293 		pci_write_config_word(dev, PCI_COMMAND, cmd);
294 	}
295 	return 0;
296 }
297