xref: /openbmc/linux/drivers/pci/setup-res.c (revision a1e58bbd)
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
30 pci_update_resource(struct pci_dev *dev, struct resource *res, int resno)
31 {
32 	struct pci_bus_region region;
33 	u32 new, check, mask;
34 	int reg;
35 
36 	/*
37 	 * Ignore resources for unimplemented BARs and unused resource slots
38 	 * for 64 bit BARs.
39 	 */
40 	if (!res->flags)
41 		return;
42 
43 	/*
44 	 * Ignore non-moveable resources.  This might be legacy resources for
45 	 * which no functional BAR register exists or another important
46 	 * system resource we should better not move around in system address
47 	 * space.
48 	 */
49 	if (res->flags & IORESOURCE_PCI_FIXED)
50 		return;
51 
52 	pcibios_resource_to_bus(dev, &region, res);
53 
54 	pr_debug("  got res [%llx:%llx] bus [%llx:%llx] flags %lx for "
55 		 "BAR %d of %s\n", (unsigned long long)res->start,
56 		 (unsigned long long)res->end,
57 		 (unsigned long long)region.start,
58 		 (unsigned long long)region.end,
59 		 (unsigned long)res->flags, resno, pci_name(dev));
60 
61 	new = region.start | (res->flags & PCI_REGION_FLAG_MASK);
62 	if (res->flags & IORESOURCE_IO)
63 		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
64 	else
65 		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
66 
67 	if (resno < 6) {
68 		reg = PCI_BASE_ADDRESS_0 + 4 * resno;
69 	} else if (resno == PCI_ROM_RESOURCE) {
70 		if (!(res->flags & IORESOURCE_ROM_ENABLE))
71 			return;
72 		new |= PCI_ROM_ADDRESS_ENABLE;
73 		reg = dev->rom_base_reg;
74 	} else {
75 		/* Hmm, non-standard resource. */
76 
77 		return;		/* kill uninitialised var warning */
78 	}
79 
80 	pci_write_config_dword(dev, reg, new);
81 	pci_read_config_dword(dev, reg, &check);
82 
83 	if ((new ^ check) & mask) {
84 		printk(KERN_ERR "PCI: Error while updating region "
85 		       "%s/%d (%08x != %08x)\n", pci_name(dev), resno,
86 		       new, check);
87 	}
88 
89 	if ((new & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
90 	    (PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64)) {
91 		new = region.start >> 16 >> 16;
92 		pci_write_config_dword(dev, reg + 4, new);
93 		pci_read_config_dword(dev, reg + 4, &check);
94 		if (check != new) {
95 			printk(KERN_ERR "PCI: Error updating region "
96 			       "%s/%d (high %08x != %08x)\n",
97 			       pci_name(dev), resno, new, check);
98 		}
99 	}
100 	res->flags &= ~IORESOURCE_UNSET;
101 	pr_debug("PCI: moved device %s resource %d (%lx) to %x\n",
102 		pci_name(dev), resno, res->flags,
103 		new & ~PCI_REGION_FLAG_MASK);
104 }
105 
106 int pci_claim_resource(struct pci_dev *dev, int resource)
107 {
108 	struct resource *res = &dev->resource[resource];
109 	struct resource *root = NULL;
110 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
111 	int err;
112 
113 	root = pcibios_select_root(dev, res);
114 
115 	err = -EINVAL;
116 	if (root != NULL)
117 		err = insert_resource(root, res);
118 
119 	if (err) {
120 		printk(KERN_ERR "PCI: %s region %d of %s %s [%llx:%llx]\n",
121 			root ? "Address space collision on" :
122 				"No parent found for",
123 			resource, dtype, pci_name(dev),
124 			(unsigned long long)res->start,
125 			(unsigned long long)res->end);
126 	}
127 
128 	return err;
129 }
130 
131 int pci_assign_resource(struct pci_dev *dev, int resno)
132 {
133 	struct pci_bus *bus = dev->bus;
134 	struct resource *res = dev->resource + resno;
135 	resource_size_t size, min, align;
136 	int ret;
137 
138 	size = res->end - res->start + 1;
139 	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
140 	/* The bridge resources are special, as their
141 	   size != alignment. Sizing routines return
142 	   required alignment in the "start" field. */
143 	align = (resno < PCI_BRIDGE_RESOURCES) ? size : res->start;
144 
145 	/* First, try exact prefetching match.. */
146 	ret = pci_bus_alloc_resource(bus, res, size, align, min,
147 				     IORESOURCE_PREFETCH,
148 				     pcibios_align_resource, dev);
149 
150 	if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
151 		/*
152 		 * That failed.
153 		 *
154 		 * But a prefetching area can handle a non-prefetching
155 		 * window (it will just not perform as well).
156 		 */
157 		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
158 					     pcibios_align_resource, dev);
159 	}
160 
161 	if (ret) {
162 		printk(KERN_ERR "PCI: Failed to allocate %s resource "
163 			"#%d:%llx@%llx for %s\n",
164 			res->flags & IORESOURCE_IO ? "I/O" : "mem",
165 			resno, (unsigned long long)size,
166 			(unsigned long long)res->start, pci_name(dev));
167 	} else if (resno < PCI_BRIDGE_RESOURCES) {
168 		pci_update_resource(dev, res, resno);
169 	}
170 
171 	return ret;
172 }
173 
174 #ifdef CONFIG_EMBEDDED
175 int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
176 {
177 	struct pci_bus *bus = dev->bus;
178 	struct resource *res = dev->resource + resno;
179 	unsigned int type_mask;
180 	int i, ret = -EBUSY;
181 
182 	type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
183 
184 	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
185 		struct resource *r = bus->resource[i];
186 		if (!r)
187 			continue;
188 
189 		/* type_mask must match */
190 		if ((res->flags ^ r->flags) & type_mask)
191 			continue;
192 
193 		ret = request_resource(r, res);
194 
195 		if (ret == 0)
196 			break;
197 	}
198 
199 	if (ret) {
200 		printk(KERN_ERR "PCI: Failed to allocate %s resource "
201 				"#%d:%llx@%llx for %s\n",
202 			res->flags & IORESOURCE_IO ? "I/O" : "mem",
203 			resno, (unsigned long long)(res->end - res->start + 1),
204 			(unsigned long long)res->start, pci_name(dev));
205 	} else if (resno < PCI_BRIDGE_RESOURCES) {
206 		pci_update_resource(dev, res, resno);
207 	}
208 
209 	return ret;
210 }
211 EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
212 #endif
213 
214 /* Sort resources by alignment */
215 void pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
216 {
217 	int i;
218 
219 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
220 		struct resource *r;
221 		struct resource_list *list, *tmp;
222 		resource_size_t r_align;
223 
224 		r = &dev->resource[i];
225 
226 		if (r->flags & IORESOURCE_PCI_FIXED)
227 			continue;
228 
229 		r_align = r->end - r->start;
230 
231 		if (!(r->flags) || r->parent)
232 			continue;
233 		if (!r_align) {
234 			printk(KERN_WARNING "PCI: Ignore bogus resource %d "
235 				"[%llx:%llx] of %s\n",
236 				i, (unsigned long long)r->start,
237 				(unsigned long long)r->end, pci_name(dev));
238 			continue;
239 		}
240 		r_align = (i < PCI_BRIDGE_RESOURCES) ? r_align + 1 : r->start;
241 		for (list = head; ; list = list->next) {
242 			resource_size_t align = 0;
243 			struct resource_list *ln = list->next;
244 			int idx;
245 
246 			if (ln) {
247 				idx = ln->res - &ln->dev->resource[0];
248 				align = (idx < PCI_BRIDGE_RESOURCES) ?
249 					ln->res->end - ln->res->start + 1 :
250 					ln->res->start;
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