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