xref: /openbmc/linux/drivers/pci/setup-res.c (revision b04b4f78)
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 = NULL;
103 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
104 	int err;
105 
106 	root = pcibios_select_root(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 int pci_assign_resource(struct pci_dev *dev, int resno)
139 {
140 	struct pci_bus *bus = dev->bus;
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 
148 	align = resource_alignment(res);
149 	if (!align) {
150 		dev_info(&dev->dev, "BAR %d: can't allocate resource (bogus "
151 			"alignment) %pR flags %#lx\n",
152 			resno, res, res->flags);
153 		return -EINVAL;
154 	}
155 
156 	/* First, try exact prefetching match.. */
157 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
158 				     IORESOURCE_PREFETCH,
159 				     pcibios_align_resource, dev);
160 
161 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
162 		/*
163 		 * That failed.
164 		 *
165 		 * But a prefetching area can handle a non-prefetching
166 		 * window (it will just not perform as well).
167 		 */
168 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
169 					     pcibios_align_resource, dev);
170 	}
171 
172 	if (ret) {
173 		dev_info(&dev->dev, "BAR %d: can't allocate %s resource %pR\n",
174 			resno, res->flags & IORESOURCE_IO ? "I/O" : "mem", res);
175 	} else {
176 		res->flags &= ~IORESOURCE_STARTALIGN;
177 		if (resno < PCI_BRIDGE_RESOURCES)
178 			pci_update_resource(dev, resno);
179 	}
180 
181 	return ret;
182 }
183 
184 #if 0
185 int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
186 {
187 	struct pci_bus *bus = dev->bus;
188 	struct resource *res = dev->resource + resno;
189 	unsigned int type_mask;
190 	int i, ret = -EBUSY;
191 
192 	type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
193 
194 	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
195 		struct resource *r = bus->resource[i];
196 		if (!r)
197 			continue;
198 
199 		/* type_mask must match */
200 		if ((res->flags ^ r->flags) & type_mask)
201 			continue;
202 
203 		ret = request_resource(r, res);
204 
205 		if (ret == 0)
206 			break;
207 	}
208 
209 	if (ret) {
210 		dev_err(&dev->dev, "BAR %d: can't allocate %s resource %pR\n",
211 			resno, res->flags & IORESOURCE_IO ? "I/O" : "mem", res);
212 	} else if (resno < PCI_BRIDGE_RESOURCES) {
213 		pci_update_resource(dev, resno);
214 	}
215 
216 	return ret;
217 }
218 EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
219 #endif
220 
221 /* Sort resources by alignment */
222 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
223 {
224 	int i;
225 
226 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
227 		struct resource *r;
228 		struct resource_list *list, *tmp;
229 		resource_size_t r_align;
230 
231 		r = &dev->resource[i];
232 
233 		if (r->flags & IORESOURCE_PCI_FIXED)
234 			continue;
235 
236 		if (!(r->flags) || r->parent)
237 			continue;
238 
239 		r_align = resource_alignment(r);
240 		if (!r_align) {
241 			dev_warn(&dev->dev, "BAR %d: bogus alignment "
242 				"%pR flags %#lx\n",
243 				i, r, r->flags);
244 			continue;
245 		}
246 		for (list = head; ; list = list->next) {
247 			resource_size_t align = 0;
248 			struct resource_list *ln = list->next;
249 
250 			if (ln)
251 				align = resource_alignment(ln->res);
252 
253 			if (r_align > align) {
254 				tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
255 				if (!tmp)
256 					panic("pdev_sort_resources(): "
257 					      "kmalloc() failed!\n");
258 				tmp->next = ln;
259 				tmp->res = r;
260 				tmp->dev = dev;
261 				list->next = tmp;
262 				break;
263 			}
264 		}
265 	}
266 }
267 
268 int pci_enable_resources(struct pci_dev *dev, int mask)
269 {
270 	u16 cmd, old_cmd;
271 	int i;
272 	struct resource *r;
273 
274 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
275 	old_cmd = cmd;
276 
277 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
278 		if (!(mask & (1 << i)))
279 			continue;
280 
281 		r = &dev->resource[i];
282 
283 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
284 			continue;
285 		if ((i == PCI_ROM_RESOURCE) &&
286 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
287 			continue;
288 
289 		if (!r->parent) {
290 			dev_err(&dev->dev, "device not available because of "
291 				"BAR %d %pR collisions\n", i, r);
292 			return -EINVAL;
293 		}
294 
295 		if (r->flags & IORESOURCE_IO)
296 			cmd |= PCI_COMMAND_IO;
297 		if (r->flags & IORESOURCE_MEM)
298 			cmd |= PCI_COMMAND_MEMORY;
299 	}
300 
301 	if (cmd != old_cmd) {
302 		dev_info(&dev->dev, "enabling device (%04x -> %04x)\n",
303 			 old_cmd, cmd);
304 		pci_write_config_word(dev, PCI_COMMAND, cmd);
305 	}
306 	return 0;
307 }
308