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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Support routines for initializing a PCI subsystem
4 *
5 * Extruded from code written by
6 * Dave Rusling (david.rusling@reo.mts.dec.com)
7 * David Mosberger (davidm@cs.arizona.edu)
8 * David Miller (davem@redhat.com)
9 *
10 * Fixed for multiple PCI buses, 1999 Andrea Arcangeli <andrea@suse.de>
11 *
12 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
13 * Resource sorting
14 */
15
16#include <linux/kernel.h>
17#include <linux/export.h>
18#include <linux/pci.h>
19#include <linux/errno.h>
20#include <linux/ioport.h>
21#include <linux/cache.h>
22#include <linux/slab.h>
23#include "pci.h"
24
25static void pci_std_update_resource(struct pci_dev *dev, int resno)
26{
27 struct pci_bus_region region;
28 bool disable;
29 u16 cmd;
30 u32 new, check, mask;
31 int reg;
32 struct resource *res = dev->resource + resno;
33
34 /* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */
35 if (dev->is_virtfn)
36 return;
37
38 /*
39 * Ignore resources for unimplemented BARs and unused resource slots
40 * for 64 bit BARs.
41 */
42 if (!res->flags)
43 return;
44
45 if (res->flags & IORESOURCE_UNSET)
46 return;
47
48 /*
49 * Ignore non-moveable resources. This might be legacy resources for
50 * which no functional BAR register exists or another important
51 * system resource we shouldn't move around.
52 */
53 if (res->flags & IORESOURCE_PCI_FIXED)
54 return;
55
56 pcibios_resource_to_bus(dev->bus, ®ion, res);
57 new = region.start;
58
59 if (res->flags & IORESOURCE_IO) {
60 mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
61 new |= res->flags & ~PCI_BASE_ADDRESS_IO_MASK;
62 } else if (resno == PCI_ROM_RESOURCE) {
63 mask = PCI_ROM_ADDRESS_MASK;
64 } else {
65 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
66 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
67 }
68
69 if (resno < PCI_ROM_RESOURCE) {
70 reg = PCI_BASE_ADDRESS_0 + 4 * resno;
71 } else if (resno == PCI_ROM_RESOURCE) {
72
73 /*
74 * Apparently some Matrox devices have ROM BARs that read
75 * as zero when disabled, so don't update ROM BARs unless
76 * they're enabled. See
77 * https://lore.kernel.org/r/43147B3D.1030309@vc.cvut.cz/
78 */
79 if (!(res->flags & IORESOURCE_ROM_ENABLE))
80 return;
81
82 reg = dev->rom_base_reg;
83 new |= PCI_ROM_ADDRESS_ENABLE;
84 } else
85 return;
86
87 /*
88 * We can't update a 64-bit BAR atomically, so when possible,
89 * disable decoding so that a half-updated BAR won't conflict
90 * with another device.
91 */
92 disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
93 if (disable) {
94 pci_read_config_word(dev, PCI_COMMAND, &cmd);
95 pci_write_config_word(dev, PCI_COMMAND,
96 cmd & ~PCI_COMMAND_MEMORY);
97 }
98
99 pci_write_config_dword(dev, reg, new);
100 pci_read_config_dword(dev, reg, &check);
101
102 if ((new ^ check) & mask) {
103 pci_err(dev, "BAR %d: error updating (%#08x != %#08x)\n",
104 resno, new, check);
105 }
106
107 if (res->flags & IORESOURCE_MEM_64) {
108 new = region.start >> 16 >> 16;
109 pci_write_config_dword(dev, reg + 4, new);
110 pci_read_config_dword(dev, reg + 4, &check);
111 if (check != new) {
112 pci_err(dev, "BAR %d: error updating (high %#08x != %#08x)\n",
113 resno, new, check);
114 }
115 }
116
117 if (disable)
118 pci_write_config_word(dev, PCI_COMMAND, cmd);
119}
120
121void pci_update_resource(struct pci_dev *dev, int resno)
122{
123 if (resno <= PCI_ROM_RESOURCE)
124 pci_std_update_resource(dev, resno);
125#ifdef CONFIG_PCI_IOV
126 else if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
127 pci_iov_update_resource(dev, resno);
128#endif
129}
130
131int pci_claim_resource(struct pci_dev *dev, int resource)
132{
133 struct resource *res = &dev->resource[resource];
134 struct resource *root, *conflict;
135
136 if (res->flags & IORESOURCE_UNSET) {
137 pci_info(dev, "can't claim BAR %d %pR: no address assigned\n",
138 resource, res);
139 return -EINVAL;
140 }
141
142 /*
143 * If we have a shadow copy in RAM, the PCI device doesn't respond
144 * to the shadow range, so we don't need to claim it, and upstream
145 * bridges don't need to route the range to the device.
146 */
147 if (res->flags & IORESOURCE_ROM_SHADOW)
148 return 0;
149
150 root = pci_find_parent_resource(dev, res);
151 if (!root) {
152 pci_info(dev, "can't claim BAR %d %pR: no compatible bridge window\n",
153 resource, res);
154 res->flags |= IORESOURCE_UNSET;
155 return -EINVAL;
156 }
157
158 conflict = request_resource_conflict(root, res);
159 if (conflict) {
160 pci_info(dev, "can't claim BAR %d %pR: address conflict with %s %pR\n",
161 resource, res, conflict->name, conflict);
162 res->flags |= IORESOURCE_UNSET;
163 return -EBUSY;
164 }
165
166 return 0;
167}
168EXPORT_SYMBOL(pci_claim_resource);
169
170void pci_disable_bridge_window(struct pci_dev *dev)
171{
172 /* MMIO Base/Limit */
173 pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
174
175 /* Prefetchable MMIO Base/Limit */
176 pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
177 pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
178 pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
179}
180
181/*
182 * Generic function that returns a value indicating that the device's
183 * original BIOS BAR address was not saved and so is not available for
184 * reinstatement.
185 *
186 * Can be over-ridden by architecture specific code that implements
187 * reinstatement functionality rather than leaving it disabled when
188 * normal allocation attempts fail.
189 */
190resource_size_t __weak pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
191{
192 return 0;
193}
194
195static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
196 int resno, resource_size_t size)
197{
198 struct resource *root, *conflict;
199 resource_size_t fw_addr, start, end;
200
201 fw_addr = pcibios_retrieve_fw_addr(dev, resno);
202 if (!fw_addr)
203 return -ENOMEM;
204
205 start = res->start;
206 end = res->end;
207 res->start = fw_addr;
208 res->end = res->start + size - 1;
209 res->flags &= ~IORESOURCE_UNSET;
210
211 root = pci_find_parent_resource(dev, res);
212 if (!root) {
213 if (res->flags & IORESOURCE_IO)
214 root = &ioport_resource;
215 else
216 root = &iomem_resource;
217 }
218
219 pci_info(dev, "BAR %d: trying firmware assignment %pR\n",
220 resno, res);
221 conflict = request_resource_conflict(root, res);
222 if (conflict) {
223 pci_info(dev, "BAR %d: %pR conflicts with %s %pR\n",
224 resno, res, conflict->name, conflict);
225 res->start = start;
226 res->end = end;
227 res->flags |= IORESOURCE_UNSET;
228 return -EBUSY;
229 }
230 return 0;
231}
232
233/*
234 * We don't have to worry about legacy ISA devices, so nothing to do here.
235 * This is marked as __weak because multiple architectures define it; it should
236 * eventually go away.
237 */
238resource_size_t __weak pcibios_align_resource(void *data,
239 const struct resource *res,
240 resource_size_t size,
241 resource_size_t align)
242{
243 return res->start;
244}
245
246static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
247 int resno, resource_size_t size, resource_size_t align)
248{
249 struct resource *res = dev->resource + resno;
250 resource_size_t min;
251 int ret;
252
253 min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
254
255 /*
256 * First, try exact prefetching match. Even if a 64-bit
257 * prefetchable bridge window is below 4GB, we can't put a 32-bit
258 * prefetchable resource in it because pbus_size_mem() assumes a
259 * 64-bit window will contain no 32-bit resources. If we assign
260 * things differently than they were sized, not everything will fit.
261 */
262 ret = pci_bus_alloc_resource(bus, res, size, align, min,
263 IORESOURCE_PREFETCH | IORESOURCE_MEM_64,
264 pcibios_align_resource, dev);
265 if (ret == 0)
266 return 0;
267
268 /*
269 * If the prefetchable window is only 32 bits wide, we can put
270 * 64-bit prefetchable resources in it.
271 */
272 if ((res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) ==
273 (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) {
274 ret = pci_bus_alloc_resource(bus, res, size, align, min,
275 IORESOURCE_PREFETCH,
276 pcibios_align_resource, dev);
277 if (ret == 0)
278 return 0;
279 }
280
281 /*
282 * If we didn't find a better match, we can put any memory resource
283 * in a non-prefetchable window. If this resource is 32 bits and
284 * non-prefetchable, the first call already tried the only possibility
285 * so we don't need to try again.
286 */
287 if (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))
288 ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
289 pcibios_align_resource, dev);
290
291 return ret;
292}
293
294static int _pci_assign_resource(struct pci_dev *dev, int resno,
295 resource_size_t size, resource_size_t min_align)
296{
297 struct pci_bus *bus;
298 int ret;
299
300 bus = dev->bus;
301 while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
302 if (!bus->parent || !bus->self->transparent)
303 break;
304 bus = bus->parent;
305 }
306
307 return ret;
308}
309
310int pci_assign_resource(struct pci_dev *dev, int resno)
311{
312 struct resource *res = dev->resource + resno;
313 resource_size_t align, size;
314 int ret;
315
316 if (res->flags & IORESOURCE_PCI_FIXED)
317 return 0;
318
319 res->flags |= IORESOURCE_UNSET;
320 align = pci_resource_alignment(dev, res);
321 if (!align) {
322 pci_info(dev, "BAR %d: can't assign %pR (bogus alignment)\n",
323 resno, res);
324 return -EINVAL;
325 }
326
327 size = resource_size(res);
328 ret = _pci_assign_resource(dev, resno, size, align);
329
330 /*
331 * If we failed to assign anything, let's try the address
332 * where firmware left it. That at least has a chance of
333 * working, which is better than just leaving it disabled.
334 */
335 if (ret < 0) {
336 pci_info(dev, "BAR %d: no space for %pR\n", resno, res);
337 ret = pci_revert_fw_address(res, dev, resno, size);
338 }
339
340 if (ret < 0) {
341 pci_info(dev, "BAR %d: failed to assign %pR\n", resno, res);
342 return ret;
343 }
344
345 res->flags &= ~IORESOURCE_UNSET;
346 res->flags &= ~IORESOURCE_STARTALIGN;
347 pci_info(dev, "BAR %d: assigned %pR\n", resno, res);
348 if (resno < PCI_BRIDGE_RESOURCES)
349 pci_update_resource(dev, resno);
350
351 return 0;
352}
353EXPORT_SYMBOL(pci_assign_resource);
354
355int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsize,
356 resource_size_t min_align)
357{
358 struct resource *res = dev->resource + resno;
359 unsigned long flags;
360 resource_size_t new_size;
361 int ret;
362
363 if (res->flags & IORESOURCE_PCI_FIXED)
364 return 0;
365
366 flags = res->flags;
367 res->flags |= IORESOURCE_UNSET;
368 if (!res->parent) {
369 pci_info(dev, "BAR %d: can't reassign an unassigned resource %pR\n",
370 resno, res);
371 return -EINVAL;
372 }
373
374 /* already aligned with min_align */
375 new_size = resource_size(res) + addsize;
376 ret = _pci_assign_resource(dev, resno, new_size, min_align);
377 if (ret) {
378 res->flags = flags;
379 pci_info(dev, "BAR %d: %pR (failed to expand by %#llx)\n",
380 resno, res, (unsigned long long) addsize);
381 return ret;
382 }
383
384 res->flags &= ~IORESOURCE_UNSET;
385 res->flags &= ~IORESOURCE_STARTALIGN;
386 pci_info(dev, "BAR %d: reassigned %pR (expanded by %#llx)\n",
387 resno, res, (unsigned long long) addsize);
388 if (resno < PCI_BRIDGE_RESOURCES)
389 pci_update_resource(dev, resno);
390
391 return 0;
392}
393
394void pci_release_resource(struct pci_dev *dev, int resno)
395{
396 struct resource *res = dev->resource + resno;
397
398 pci_info(dev, "BAR %d: releasing %pR\n", resno, res);
399
400 if (!res->parent)
401 return;
402
403 release_resource(res);
404 res->end = resource_size(res) - 1;
405 res->start = 0;
406 res->flags |= IORESOURCE_UNSET;
407}
408EXPORT_SYMBOL(pci_release_resource);
409
410int pci_resize_resource(struct pci_dev *dev, int resno, int size)
411{
412 struct resource *res = dev->resource + resno;
413 int old, ret;
414 u32 sizes;
415 u16 cmd;
416
417 /* Make sure the resource isn't assigned before resizing it. */
418 if (!(res->flags & IORESOURCE_UNSET))
419 return -EBUSY;
420
421 pci_read_config_word(dev, PCI_COMMAND, &cmd);
422 if (cmd & PCI_COMMAND_MEMORY)
423 return -EBUSY;
424
425 sizes = pci_rebar_get_possible_sizes(dev, resno);
426 if (!sizes)
427 return -ENOTSUPP;
428
429 if (!(sizes & BIT(size)))
430 return -EINVAL;
431
432 old = pci_rebar_get_current_size(dev, resno);
433 if (old < 0)
434 return old;
435
436 ret = pci_rebar_set_size(dev, resno, size);
437 if (ret)
438 return ret;
439
440 res->end = res->start + pci_rebar_size_to_bytes(size) - 1;
441
442 /* Check if the new config works by trying to assign everything. */
443 if (dev->bus->self) {
444 ret = pci_reassign_bridge_resources(dev->bus->self, res->flags);
445 if (ret)
446 goto error_resize;
447 }
448 return 0;
449
450error_resize:
451 pci_rebar_set_size(dev, resno, old);
452 res->end = res->start + pci_rebar_size_to_bytes(old) - 1;
453 return ret;
454}
455EXPORT_SYMBOL(pci_resize_resource);
456
457int pci_enable_resources(struct pci_dev *dev, int mask)
458{
459 u16 cmd, old_cmd;
460 int i;
461 struct resource *r;
462
463 pci_read_config_word(dev, PCI_COMMAND, &cmd);
464 old_cmd = cmd;
465
466 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
467 if (!(mask & (1 << i)))
468 continue;
469
470 r = &dev->resource[i];
471
472 if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
473 continue;
474 if ((i == PCI_ROM_RESOURCE) &&
475 (!(r->flags & IORESOURCE_ROM_ENABLE)))
476 continue;
477
478 if (r->flags & IORESOURCE_UNSET) {
479 pci_err(dev, "can't enable device: BAR %d %pR not assigned\n",
480 i, r);
481 return -EINVAL;
482 }
483
484 if (!r->parent) {
485 pci_err(dev, "can't enable device: BAR %d %pR not claimed\n",
486 i, r);
487 return -EINVAL;
488 }
489
490 if (r->flags & IORESOURCE_IO)
491 cmd |= PCI_COMMAND_IO;
492 if (r->flags & IORESOURCE_MEM)
493 cmd |= PCI_COMMAND_MEMORY;
494 }
495
496 if (cmd != old_cmd) {
497 pci_info(dev, "enabling device (%04x -> %04x)\n", old_cmd, cmd);
498 pci_write_config_word(dev, PCI_COMMAND, cmd);
499 }
500 return 0;
501}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Support routines for initializing a PCI subsystem
4 *
5 * Extruded from code written by
6 * Dave Rusling (david.rusling@reo.mts.dec.com)
7 * David Mosberger (davidm@cs.arizona.edu)
8 * David Miller (davem@redhat.com)
9 *
10 * Fixed for multiple PCI buses, 1999 Andrea Arcangeli <andrea@suse.de>
11 *
12 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
13 * Resource sorting
14 */
15
16#include <linux/kernel.h>
17#include <linux/export.h>
18#include <linux/pci.h>
19#include <linux/errno.h>
20#include <linux/ioport.h>
21#include <linux/cache.h>
22#include <linux/slab.h>
23#include "pci.h"
24
25static void pci_std_update_resource(struct pci_dev *dev, int resno)
26{
27 struct pci_bus_region region;
28 bool disable;
29 u16 cmd;
30 u32 new, check, mask;
31 int reg;
32 struct resource *res = dev->resource + resno;
33 const char *res_name = pci_resource_name(dev, resno);
34
35 /* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */
36 if (dev->is_virtfn)
37 return;
38
39 /*
40 * Ignore resources for unimplemented BARs and unused resource slots
41 * for 64 bit BARs.
42 */
43 if (!res->flags)
44 return;
45
46 if (res->flags & IORESOURCE_UNSET)
47 return;
48
49 /*
50 * Ignore non-moveable resources. This might be legacy resources for
51 * which no functional BAR register exists or another important
52 * system resource we shouldn't move around.
53 */
54 if (res->flags & IORESOURCE_PCI_FIXED)
55 return;
56
57 pcibios_resource_to_bus(dev->bus, ®ion, res);
58 new = region.start;
59
60 if (res->flags & IORESOURCE_IO) {
61 mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
62 new |= res->flags & ~PCI_BASE_ADDRESS_IO_MASK;
63 } else if (resno == PCI_ROM_RESOURCE) {
64 mask = PCI_ROM_ADDRESS_MASK;
65 } else {
66 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
67 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
68 }
69
70 if (resno < PCI_ROM_RESOURCE) {
71 reg = PCI_BASE_ADDRESS_0 + 4 * resno;
72 } else if (resno == PCI_ROM_RESOURCE) {
73
74 /*
75 * Apparently some Matrox devices have ROM BARs that read
76 * as zero when disabled, so don't update ROM BARs unless
77 * they're enabled. See
78 * https://lore.kernel.org/r/43147B3D.1030309@vc.cvut.cz/
79 * But we must update ROM BAR for buggy devices where even a
80 * disabled ROM can conflict with other BARs.
81 */
82 if (!(res->flags & IORESOURCE_ROM_ENABLE) &&
83 !dev->rom_bar_overlap)
84 return;
85
86 reg = dev->rom_base_reg;
87 if (res->flags & IORESOURCE_ROM_ENABLE)
88 new |= PCI_ROM_ADDRESS_ENABLE;
89 } else
90 return;
91
92 /*
93 * We can't update a 64-bit BAR atomically, so when possible,
94 * disable decoding so that a half-updated BAR won't conflict
95 * with another device.
96 */
97 disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
98 if (disable) {
99 pci_read_config_word(dev, PCI_COMMAND, &cmd);
100 pci_write_config_word(dev, PCI_COMMAND,
101 cmd & ~PCI_COMMAND_MEMORY);
102 }
103
104 pci_write_config_dword(dev, reg, new);
105 pci_read_config_dword(dev, reg, &check);
106
107 if ((new ^ check) & mask) {
108 pci_err(dev, "%s: error updating (%#010x != %#010x)\n",
109 res_name, new, check);
110 }
111
112 if (res->flags & IORESOURCE_MEM_64) {
113 new = region.start >> 16 >> 16;
114 pci_write_config_dword(dev, reg + 4, new);
115 pci_read_config_dword(dev, reg + 4, &check);
116 if (check != new) {
117 pci_err(dev, "%s: error updating (high %#010x != %#010x)\n",
118 res_name, new, check);
119 }
120 }
121
122 if (disable)
123 pci_write_config_word(dev, PCI_COMMAND, cmd);
124}
125
126void pci_update_resource(struct pci_dev *dev, int resno)
127{
128 if (resno <= PCI_ROM_RESOURCE)
129 pci_std_update_resource(dev, resno);
130#ifdef CONFIG_PCI_IOV
131 else if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
132 pci_iov_update_resource(dev, resno);
133#endif
134}
135
136int pci_claim_resource(struct pci_dev *dev, int resource)
137{
138 struct resource *res = &dev->resource[resource];
139 const char *res_name = pci_resource_name(dev, resource);
140 struct resource *root, *conflict;
141
142 if (res->flags & IORESOURCE_UNSET) {
143 pci_info(dev, "%s %pR: can't claim; no address assigned\n",
144 res_name, res);
145 return -EINVAL;
146 }
147
148 /*
149 * If we have a shadow copy in RAM, the PCI device doesn't respond
150 * to the shadow range, so we don't need to claim it, and upstream
151 * bridges don't need to route the range to the device.
152 */
153 if (res->flags & IORESOURCE_ROM_SHADOW)
154 return 0;
155
156 root = pci_find_parent_resource(dev, res);
157 if (!root) {
158 pci_info(dev, "%s %pR: can't claim; no compatible bridge window\n",
159 res_name, res);
160 res->flags |= IORESOURCE_UNSET;
161 return -EINVAL;
162 }
163
164 conflict = request_resource_conflict(root, res);
165 if (conflict) {
166 pci_info(dev, "%s %pR: can't claim; address conflict with %s %pR\n",
167 res_name, res, conflict->name, conflict);
168 res->flags |= IORESOURCE_UNSET;
169 return -EBUSY;
170 }
171
172 return 0;
173}
174EXPORT_SYMBOL(pci_claim_resource);
175
176void pci_disable_bridge_window(struct pci_dev *dev)
177{
178 /* MMIO Base/Limit */
179 pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
180
181 /* Prefetchable MMIO Base/Limit */
182 pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
183 pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
184 pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
185}
186
187/*
188 * Generic function that returns a value indicating that the device's
189 * original BIOS BAR address was not saved and so is not available for
190 * reinstatement.
191 *
192 * Can be over-ridden by architecture specific code that implements
193 * reinstatement functionality rather than leaving it disabled when
194 * normal allocation attempts fail.
195 */
196resource_size_t __weak pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
197{
198 return 0;
199}
200
201static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
202 int resno, resource_size_t size)
203{
204 struct resource *root, *conflict;
205 resource_size_t fw_addr, start, end;
206 const char *res_name = pci_resource_name(dev, resno);
207
208 fw_addr = pcibios_retrieve_fw_addr(dev, resno);
209 if (!fw_addr)
210 return -ENOMEM;
211
212 start = res->start;
213 end = res->end;
214 resource_set_range(res, fw_addr, size);
215 res->flags &= ~IORESOURCE_UNSET;
216
217 root = pci_find_parent_resource(dev, res);
218 if (!root) {
219 /*
220 * If dev is behind a bridge, accesses will only reach it
221 * if res is inside the relevant bridge window.
222 */
223 if (pci_upstream_bridge(dev))
224 return -ENXIO;
225
226 /*
227 * On the root bus, assume the host bridge will forward
228 * everything.
229 */
230 if (res->flags & IORESOURCE_IO)
231 root = &ioport_resource;
232 else
233 root = &iomem_resource;
234 }
235
236 pci_info(dev, "%s: trying firmware assignment %pR\n", res_name, res);
237 conflict = request_resource_conflict(root, res);
238 if (conflict) {
239 pci_info(dev, "%s %pR: conflicts with %s %pR\n", res_name, res,
240 conflict->name, conflict);
241 res->start = start;
242 res->end = end;
243 res->flags |= IORESOURCE_UNSET;
244 return -EBUSY;
245 }
246 return 0;
247}
248
249/*
250 * We don't have to worry about legacy ISA devices, so nothing to do here.
251 * This is marked as __weak because multiple architectures define it; it should
252 * eventually go away.
253 */
254resource_size_t __weak pcibios_align_resource(void *data,
255 const struct resource *res,
256 resource_size_t size,
257 resource_size_t align)
258{
259 return res->start;
260}
261
262static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
263 int resno, resource_size_t size, resource_size_t align)
264{
265 struct resource *res = dev->resource + resno;
266 resource_size_t min;
267 int ret;
268
269 min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
270
271 /*
272 * First, try exact prefetching match. Even if a 64-bit
273 * prefetchable bridge window is below 4GB, we can't put a 32-bit
274 * prefetchable resource in it because pbus_size_mem() assumes a
275 * 64-bit window will contain no 32-bit resources. If we assign
276 * things differently than they were sized, not everything will fit.
277 */
278 ret = pci_bus_alloc_resource(bus, res, size, align, min,
279 IORESOURCE_PREFETCH | IORESOURCE_MEM_64,
280 pcibios_align_resource, dev);
281 if (ret == 0)
282 return 0;
283
284 /*
285 * If the prefetchable window is only 32 bits wide, we can put
286 * 64-bit prefetchable resources in it.
287 */
288 if ((res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) ==
289 (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) {
290 ret = pci_bus_alloc_resource(bus, res, size, align, min,
291 IORESOURCE_PREFETCH,
292 pcibios_align_resource, dev);
293 if (ret == 0)
294 return 0;
295 }
296
297 /*
298 * If we didn't find a better match, we can put any memory resource
299 * in a non-prefetchable window. If this resource is 32 bits and
300 * non-prefetchable, the first call already tried the only possibility
301 * so we don't need to try again.
302 */
303 if (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))
304 ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
305 pcibios_align_resource, dev);
306
307 return ret;
308}
309
310static int _pci_assign_resource(struct pci_dev *dev, int resno,
311 resource_size_t size, resource_size_t min_align)
312{
313 struct pci_bus *bus;
314 int ret;
315
316 bus = dev->bus;
317 while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
318 if (!bus->parent || !bus->self->transparent)
319 break;
320 bus = bus->parent;
321 }
322
323 return ret;
324}
325
326int pci_assign_resource(struct pci_dev *dev, int resno)
327{
328 struct resource *res = dev->resource + resno;
329 const char *res_name = pci_resource_name(dev, resno);
330 resource_size_t align, size;
331 int ret;
332
333 if (res->flags & IORESOURCE_PCI_FIXED)
334 return 0;
335
336 res->flags |= IORESOURCE_UNSET;
337 align = pci_resource_alignment(dev, res);
338 if (!align) {
339 pci_info(dev, "%s %pR: can't assign; bogus alignment\n",
340 res_name, res);
341 return -EINVAL;
342 }
343
344 size = resource_size(res);
345 ret = _pci_assign_resource(dev, resno, size, align);
346
347 /*
348 * If we failed to assign anything, let's try the address
349 * where firmware left it. That at least has a chance of
350 * working, which is better than just leaving it disabled.
351 */
352 if (ret < 0) {
353 pci_info(dev, "%s %pR: can't assign; no space\n", res_name, res);
354 ret = pci_revert_fw_address(res, dev, resno, size);
355 }
356
357 if (ret < 0) {
358 pci_info(dev, "%s %pR: failed to assign\n", res_name, res);
359 return ret;
360 }
361
362 res->flags &= ~IORESOURCE_UNSET;
363 res->flags &= ~IORESOURCE_STARTALIGN;
364 pci_info(dev, "%s %pR: assigned\n", res_name, res);
365 if (resno < PCI_BRIDGE_RESOURCES)
366 pci_update_resource(dev, resno);
367
368 return 0;
369}
370EXPORT_SYMBOL(pci_assign_resource);
371
372int pci_reassign_resource(struct pci_dev *dev, int resno,
373 resource_size_t addsize, resource_size_t min_align)
374{
375 struct resource *res = dev->resource + resno;
376 const char *res_name = pci_resource_name(dev, resno);
377 unsigned long flags;
378 resource_size_t new_size;
379 int ret;
380
381 if (res->flags & IORESOURCE_PCI_FIXED)
382 return 0;
383
384 flags = res->flags;
385 res->flags |= IORESOURCE_UNSET;
386 if (!res->parent) {
387 pci_info(dev, "%s %pR: can't reassign; unassigned resource\n",
388 res_name, res);
389 return -EINVAL;
390 }
391
392 /* already aligned with min_align */
393 new_size = resource_size(res) + addsize;
394 ret = _pci_assign_resource(dev, resno, new_size, min_align);
395 if (ret) {
396 res->flags = flags;
397 pci_info(dev, "%s %pR: failed to expand by %#llx\n",
398 res_name, res, (unsigned long long) addsize);
399 return ret;
400 }
401
402 res->flags &= ~IORESOURCE_UNSET;
403 res->flags &= ~IORESOURCE_STARTALIGN;
404 pci_info(dev, "%s %pR: reassigned; expanded by %#llx\n",
405 res_name, res, (unsigned long long) addsize);
406 if (resno < PCI_BRIDGE_RESOURCES)
407 pci_update_resource(dev, resno);
408
409 return 0;
410}
411
412void pci_release_resource(struct pci_dev *dev, int resno)
413{
414 struct resource *res = dev->resource + resno;
415 const char *res_name = pci_resource_name(dev, resno);
416
417 pci_info(dev, "%s %pR: releasing\n", res_name, res);
418
419 if (!res->parent)
420 return;
421
422 release_resource(res);
423 res->end = resource_size(res) - 1;
424 res->start = 0;
425 res->flags |= IORESOURCE_UNSET;
426}
427EXPORT_SYMBOL(pci_release_resource);
428
429int pci_resize_resource(struct pci_dev *dev, int resno, int size)
430{
431 struct resource *res = dev->resource + resno;
432 struct pci_host_bridge *host;
433 int old, ret;
434 u32 sizes;
435 u16 cmd;
436
437 /* Check if we must preserve the firmware's resource assignment */
438 host = pci_find_host_bridge(dev->bus);
439 if (host->preserve_config)
440 return -ENOTSUPP;
441
442 /* Make sure the resource isn't assigned before resizing it. */
443 if (!(res->flags & IORESOURCE_UNSET))
444 return -EBUSY;
445
446 pci_read_config_word(dev, PCI_COMMAND, &cmd);
447 if (cmd & PCI_COMMAND_MEMORY)
448 return -EBUSY;
449
450 sizes = pci_rebar_get_possible_sizes(dev, resno);
451 if (!sizes)
452 return -ENOTSUPP;
453
454 if (!(sizes & BIT(size)))
455 return -EINVAL;
456
457 old = pci_rebar_get_current_size(dev, resno);
458 if (old < 0)
459 return old;
460
461 ret = pci_rebar_set_size(dev, resno, size);
462 if (ret)
463 return ret;
464
465 resource_set_size(res, pci_rebar_size_to_bytes(size));
466
467 /* Check if the new config works by trying to assign everything. */
468 if (dev->bus->self) {
469 ret = pci_reassign_bridge_resources(dev->bus->self, res->flags);
470 if (ret)
471 goto error_resize;
472 }
473 return 0;
474
475error_resize:
476 pci_rebar_set_size(dev, resno, old);
477 resource_set_size(res, pci_rebar_size_to_bytes(old));
478 return ret;
479}
480EXPORT_SYMBOL(pci_resize_resource);
481
482int pci_enable_resources(struct pci_dev *dev, int mask)
483{
484 u16 cmd, old_cmd;
485 int i;
486 struct resource *r;
487 const char *r_name;
488
489 pci_read_config_word(dev, PCI_COMMAND, &cmd);
490 old_cmd = cmd;
491
492 pci_dev_for_each_resource(dev, r, i) {
493 if (!(mask & (1 << i)))
494 continue;
495
496 r_name = pci_resource_name(dev, i);
497
498 if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
499 continue;
500 if ((i == PCI_ROM_RESOURCE) &&
501 (!(r->flags & IORESOURCE_ROM_ENABLE)))
502 continue;
503
504 if (r->flags & IORESOURCE_UNSET) {
505 pci_err(dev, "%s %pR: not assigned; can't enable device\n",
506 r_name, r);
507 return -EINVAL;
508 }
509
510 if (!r->parent) {
511 pci_err(dev, "%s %pR: not claimed; can't enable device\n",
512 r_name, r);
513 return -EINVAL;
514 }
515
516 if (r->flags & IORESOURCE_IO)
517 cmd |= PCI_COMMAND_IO;
518 if (r->flags & IORESOURCE_MEM)
519 cmd |= PCI_COMMAND_MEMORY;
520 }
521
522 if (cmd != old_cmd) {
523 pci_info(dev, "enabling device (%04x -> %04x)\n", old_cmd, cmd);
524 pci_write_config_word(dev, PCI_COMMAND, cmd);
525 }
526 return 0;
527}