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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI Express I/O Virtualization (IOV) support
4 * Address Translation Service 1.0
5 * Page Request Interface added by Joerg Roedel <joerg.roedel@amd.com>
6 * PASID support added by Joerg Roedel <joerg.roedel@amd.com>
7 *
8 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
9 * Copyright (C) 2011 Advanced Micro Devices,
10 */
11
12#include <linux/bitfield.h>
13#include <linux/export.h>
14#include <linux/pci-ats.h>
15#include <linux/pci.h>
16#include <linux/slab.h>
17
18#include "pci.h"
19
20void pci_ats_init(struct pci_dev *dev)
21{
22 int pos;
23
24 if (pci_ats_disabled())
25 return;
26
27 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS);
28 if (!pos)
29 return;
30
31 dev->ats_cap = pos;
32}
33
34/**
35 * pci_ats_supported - check if the device can use ATS
36 * @dev: the PCI device
37 *
38 * Returns true if the device supports ATS and is allowed to use it, false
39 * otherwise.
40 */
41bool pci_ats_supported(struct pci_dev *dev)
42{
43 if (!dev->ats_cap)
44 return false;
45
46 return (dev->untrusted == 0);
47}
48EXPORT_SYMBOL_GPL(pci_ats_supported);
49
50/**
51 * pci_prepare_ats - Setup the PS for ATS
52 * @dev: the PCI device
53 * @ps: the IOMMU page shift
54 *
55 * This must be done by the IOMMU driver on the PF before any VFs are created to
56 * ensure that the VF can have ATS enabled.
57 *
58 * Returns 0 on success, or negative on failure.
59 */
60int pci_prepare_ats(struct pci_dev *dev, int ps)
61{
62 u16 ctrl;
63
64 if (!pci_ats_supported(dev))
65 return -EINVAL;
66
67 if (WARN_ON(dev->ats_enabled))
68 return -EBUSY;
69
70 if (ps < PCI_ATS_MIN_STU)
71 return -EINVAL;
72
73 if (dev->is_virtfn)
74 return 0;
75
76 dev->ats_stu = ps;
77 ctrl = PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
78 pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
79 return 0;
80}
81EXPORT_SYMBOL_GPL(pci_prepare_ats);
82
83/**
84 * pci_enable_ats - enable the ATS capability
85 * @dev: the PCI device
86 * @ps: the IOMMU page shift
87 *
88 * Returns 0 on success, or negative on failure.
89 */
90int pci_enable_ats(struct pci_dev *dev, int ps)
91{
92 u16 ctrl;
93 struct pci_dev *pdev;
94
95 if (!pci_ats_supported(dev))
96 return -EINVAL;
97
98 if (WARN_ON(dev->ats_enabled))
99 return -EBUSY;
100
101 if (ps < PCI_ATS_MIN_STU)
102 return -EINVAL;
103
104 /*
105 * Note that enabling ATS on a VF fails unless it's already enabled
106 * with the same STU on the PF.
107 */
108 ctrl = PCI_ATS_CTRL_ENABLE;
109 if (dev->is_virtfn) {
110 pdev = pci_physfn(dev);
111 if (pdev->ats_stu != ps)
112 return -EINVAL;
113 } else {
114 dev->ats_stu = ps;
115 ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
116 }
117 pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
118
119 dev->ats_enabled = 1;
120 return 0;
121}
122EXPORT_SYMBOL_GPL(pci_enable_ats);
123
124/**
125 * pci_disable_ats - disable the ATS capability
126 * @dev: the PCI device
127 */
128void pci_disable_ats(struct pci_dev *dev)
129{
130 u16 ctrl;
131
132 if (WARN_ON(!dev->ats_enabled))
133 return;
134
135 pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, &ctrl);
136 ctrl &= ~PCI_ATS_CTRL_ENABLE;
137 pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
138
139 dev->ats_enabled = 0;
140}
141EXPORT_SYMBOL_GPL(pci_disable_ats);
142
143void pci_restore_ats_state(struct pci_dev *dev)
144{
145 u16 ctrl;
146
147 if (!dev->ats_enabled)
148 return;
149
150 ctrl = PCI_ATS_CTRL_ENABLE;
151 if (!dev->is_virtfn)
152 ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
153 pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
154}
155
156/**
157 * pci_ats_queue_depth - query the ATS Invalidate Queue Depth
158 * @dev: the PCI device
159 *
160 * Returns the queue depth on success, or negative on failure.
161 *
162 * The ATS spec uses 0 in the Invalidate Queue Depth field to
163 * indicate that the function can accept 32 Invalidate Request.
164 * But here we use the `real' values (i.e. 1~32) for the Queue
165 * Depth; and 0 indicates the function shares the Queue with
166 * other functions (doesn't exclusively own a Queue).
167 */
168int pci_ats_queue_depth(struct pci_dev *dev)
169{
170 u16 cap;
171
172 if (!dev->ats_cap)
173 return -EINVAL;
174
175 if (dev->is_virtfn)
176 return 0;
177
178 pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CAP, &cap);
179 return PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) : PCI_ATS_MAX_QDEP;
180}
181
182/**
183 * pci_ats_page_aligned - Return Page Aligned Request bit status.
184 * @pdev: the PCI device
185 *
186 * Returns 1, if the Untranslated Addresses generated by the device
187 * are always aligned or 0 otherwise.
188 *
189 * Per PCIe spec r4.0, sec 10.5.1.2, if the Page Aligned Request bit
190 * is set, it indicates the Untranslated Addresses generated by the
191 * device are always aligned to a 4096 byte boundary.
192 */
193int pci_ats_page_aligned(struct pci_dev *pdev)
194{
195 u16 cap;
196
197 if (!pdev->ats_cap)
198 return 0;
199
200 pci_read_config_word(pdev, pdev->ats_cap + PCI_ATS_CAP, &cap);
201
202 if (cap & PCI_ATS_CAP_PAGE_ALIGNED)
203 return 1;
204
205 return 0;
206}
207
208#ifdef CONFIG_PCI_PRI
209void pci_pri_init(struct pci_dev *pdev)
210{
211 u16 status;
212
213 pdev->pri_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
214
215 if (!pdev->pri_cap)
216 return;
217
218 pci_read_config_word(pdev, pdev->pri_cap + PCI_PRI_STATUS, &status);
219 if (status & PCI_PRI_STATUS_PASID)
220 pdev->pasid_required = 1;
221}
222
223/**
224 * pci_enable_pri - Enable PRI capability
225 * @pdev: PCI device structure
226 * @reqs: outstanding requests
227 *
228 * Returns 0 on success, negative value on error
229 */
230int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
231{
232 u16 control, status;
233 u32 max_requests;
234 int pri = pdev->pri_cap;
235
236 /*
237 * VFs must not implement the PRI Capability. If their PF
238 * implements PRI, it is shared by the VFs, so if the PF PRI is
239 * enabled, it is also enabled for the VF.
240 */
241 if (pdev->is_virtfn) {
242 if (pci_physfn(pdev)->pri_enabled)
243 return 0;
244 return -EINVAL;
245 }
246
247 if (WARN_ON(pdev->pri_enabled))
248 return -EBUSY;
249
250 if (!pri)
251 return -EINVAL;
252
253 pci_read_config_word(pdev, pri + PCI_PRI_STATUS, &status);
254 if (!(status & PCI_PRI_STATUS_STOPPED))
255 return -EBUSY;
256
257 pci_read_config_dword(pdev, pri + PCI_PRI_MAX_REQ, &max_requests);
258 reqs = min(max_requests, reqs);
259 pdev->pri_reqs_alloc = reqs;
260 pci_write_config_dword(pdev, pri + PCI_PRI_ALLOC_REQ, reqs);
261
262 control = PCI_PRI_CTRL_ENABLE;
263 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
264
265 pdev->pri_enabled = 1;
266
267 return 0;
268}
269
270/**
271 * pci_disable_pri - Disable PRI capability
272 * @pdev: PCI device structure
273 *
274 * Only clears the enabled-bit, regardless of its former value
275 */
276void pci_disable_pri(struct pci_dev *pdev)
277{
278 u16 control;
279 int pri = pdev->pri_cap;
280
281 /* VFs share the PF PRI */
282 if (pdev->is_virtfn)
283 return;
284
285 if (WARN_ON(!pdev->pri_enabled))
286 return;
287
288 if (!pri)
289 return;
290
291 pci_read_config_word(pdev, pri + PCI_PRI_CTRL, &control);
292 control &= ~PCI_PRI_CTRL_ENABLE;
293 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
294
295 pdev->pri_enabled = 0;
296}
297EXPORT_SYMBOL_GPL(pci_disable_pri);
298
299/**
300 * pci_restore_pri_state - Restore PRI
301 * @pdev: PCI device structure
302 */
303void pci_restore_pri_state(struct pci_dev *pdev)
304{
305 u16 control = PCI_PRI_CTRL_ENABLE;
306 u32 reqs = pdev->pri_reqs_alloc;
307 int pri = pdev->pri_cap;
308
309 if (pdev->is_virtfn)
310 return;
311
312 if (!pdev->pri_enabled)
313 return;
314
315 if (!pri)
316 return;
317
318 pci_write_config_dword(pdev, pri + PCI_PRI_ALLOC_REQ, reqs);
319 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
320}
321
322/**
323 * pci_reset_pri - Resets device's PRI state
324 * @pdev: PCI device structure
325 *
326 * The PRI capability must be disabled before this function is called.
327 * Returns 0 on success, negative value on error.
328 */
329int pci_reset_pri(struct pci_dev *pdev)
330{
331 u16 control;
332 int pri = pdev->pri_cap;
333
334 if (pdev->is_virtfn)
335 return 0;
336
337 if (WARN_ON(pdev->pri_enabled))
338 return -EBUSY;
339
340 if (!pri)
341 return -EINVAL;
342
343 control = PCI_PRI_CTRL_RESET;
344 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
345
346 return 0;
347}
348
349/**
350 * pci_prg_resp_pasid_required - Return PRG Response PASID Required bit
351 * status.
352 * @pdev: PCI device structure
353 *
354 * Returns 1 if PASID is required in PRG Response Message, 0 otherwise.
355 */
356int pci_prg_resp_pasid_required(struct pci_dev *pdev)
357{
358 if (pdev->is_virtfn)
359 pdev = pci_physfn(pdev);
360
361 return pdev->pasid_required;
362}
363
364/**
365 * pci_pri_supported - Check if PRI is supported.
366 * @pdev: PCI device structure
367 *
368 * Returns true if PRI capability is present, false otherwise.
369 */
370bool pci_pri_supported(struct pci_dev *pdev)
371{
372 /* VFs share the PF PRI */
373 if (pci_physfn(pdev)->pri_cap)
374 return true;
375 return false;
376}
377EXPORT_SYMBOL_GPL(pci_pri_supported);
378#endif /* CONFIG_PCI_PRI */
379
380#ifdef CONFIG_PCI_PASID
381void pci_pasid_init(struct pci_dev *pdev)
382{
383 pdev->pasid_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
384}
385
386/**
387 * pci_enable_pasid - Enable the PASID capability
388 * @pdev: PCI device structure
389 * @features: Features to enable
390 *
391 * Returns 0 on success, negative value on error. This function checks
392 * whether the features are actually supported by the device and returns
393 * an error if not.
394 */
395int pci_enable_pasid(struct pci_dev *pdev, int features)
396{
397 u16 control, supported;
398 int pasid = pdev->pasid_cap;
399
400 /*
401 * VFs must not implement the PASID Capability, but if a PF
402 * supports PASID, its VFs share the PF PASID configuration.
403 */
404 if (pdev->is_virtfn) {
405 if (pci_physfn(pdev)->pasid_enabled)
406 return 0;
407 return -EINVAL;
408 }
409
410 if (WARN_ON(pdev->pasid_enabled))
411 return -EBUSY;
412
413 if (!pdev->eetlp_prefix_path && !pdev->pasid_no_tlp)
414 return -EINVAL;
415
416 if (!pasid)
417 return -EINVAL;
418
419 if (!pci_acs_path_enabled(pdev, NULL, PCI_ACS_RR | PCI_ACS_UF))
420 return -EINVAL;
421
422 pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
423 supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
424
425 /* User wants to enable anything unsupported? */
426 if ((supported & features) != features)
427 return -EINVAL;
428
429 control = PCI_PASID_CTRL_ENABLE | features;
430 pdev->pasid_features = features;
431
432 pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
433
434 pdev->pasid_enabled = 1;
435
436 return 0;
437}
438EXPORT_SYMBOL_GPL(pci_enable_pasid);
439
440/**
441 * pci_disable_pasid - Disable the PASID capability
442 * @pdev: PCI device structure
443 */
444void pci_disable_pasid(struct pci_dev *pdev)
445{
446 u16 control = 0;
447 int pasid = pdev->pasid_cap;
448
449 /* VFs share the PF PASID configuration */
450 if (pdev->is_virtfn)
451 return;
452
453 if (WARN_ON(!pdev->pasid_enabled))
454 return;
455
456 if (!pasid)
457 return;
458
459 pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
460
461 pdev->pasid_enabled = 0;
462}
463EXPORT_SYMBOL_GPL(pci_disable_pasid);
464
465/**
466 * pci_restore_pasid_state - Restore PASID capabilities
467 * @pdev: PCI device structure
468 */
469void pci_restore_pasid_state(struct pci_dev *pdev)
470{
471 u16 control;
472 int pasid = pdev->pasid_cap;
473
474 if (pdev->is_virtfn)
475 return;
476
477 if (!pdev->pasid_enabled)
478 return;
479
480 if (!pasid)
481 return;
482
483 control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features;
484 pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
485}
486
487/**
488 * pci_pasid_features - Check which PASID features are supported
489 * @pdev: PCI device structure
490 *
491 * Return a negative value when no PASID capability is present.
492 * Otherwise return a bitmask with supported features. Current
493 * features reported are:
494 * PCI_PASID_CAP_EXEC - Execute permission supported
495 * PCI_PASID_CAP_PRIV - Privileged mode supported
496 */
497int pci_pasid_features(struct pci_dev *pdev)
498{
499 u16 supported;
500 int pasid;
501
502 if (pdev->is_virtfn)
503 pdev = pci_physfn(pdev);
504
505 pasid = pdev->pasid_cap;
506 if (!pasid)
507 return -EINVAL;
508
509 pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
510
511 supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
512
513 return supported;
514}
515EXPORT_SYMBOL_GPL(pci_pasid_features);
516
517/**
518 * pci_max_pasids - Get maximum number of PASIDs supported by device
519 * @pdev: PCI device structure
520 *
521 * Returns negative value when PASID capability is not present.
522 * Otherwise it returns the number of supported PASIDs.
523 */
524int pci_max_pasids(struct pci_dev *pdev)
525{
526 u16 supported;
527 int pasid;
528
529 if (pdev->is_virtfn)
530 pdev = pci_physfn(pdev);
531
532 pasid = pdev->pasid_cap;
533 if (!pasid)
534 return -EINVAL;
535
536 pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
537
538 return (1 << FIELD_GET(PCI_PASID_CAP_WIDTH, supported));
539}
540EXPORT_SYMBOL_GPL(pci_max_pasids);
541#endif /* CONFIG_PCI_PASID */
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI Express I/O Virtualization (IOV) support
4 * Address Translation Service 1.0
5 * Page Request Interface added by Joerg Roedel <joerg.roedel@amd.com>
6 * PASID support added by Joerg Roedel <joerg.roedel@amd.com>
7 *
8 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
9 * Copyright (C) 2011 Advanced Micro Devices,
10 */
11
12#include <linux/export.h>
13#include <linux/pci-ats.h>
14#include <linux/pci.h>
15#include <linux/slab.h>
16
17#include "pci.h"
18
19void pci_ats_init(struct pci_dev *dev)
20{
21 int pos;
22
23 if (pci_ats_disabled())
24 return;
25
26 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS);
27 if (!pos)
28 return;
29
30 dev->ats_cap = pos;
31}
32
33/**
34 * pci_ats_supported - check if the device can use ATS
35 * @dev: the PCI device
36 *
37 * Returns true if the device supports ATS and is allowed to use it, false
38 * otherwise.
39 */
40bool pci_ats_supported(struct pci_dev *dev)
41{
42 if (!dev->ats_cap)
43 return false;
44
45 return (dev->untrusted == 0);
46}
47EXPORT_SYMBOL_GPL(pci_ats_supported);
48
49/**
50 * pci_enable_ats - enable the ATS capability
51 * @dev: the PCI device
52 * @ps: the IOMMU page shift
53 *
54 * Returns 0 on success, or negative on failure.
55 */
56int pci_enable_ats(struct pci_dev *dev, int ps)
57{
58 u16 ctrl;
59 struct pci_dev *pdev;
60
61 if (!pci_ats_supported(dev))
62 return -EINVAL;
63
64 if (WARN_ON(dev->ats_enabled))
65 return -EBUSY;
66
67 if (ps < PCI_ATS_MIN_STU)
68 return -EINVAL;
69
70 /*
71 * Note that enabling ATS on a VF fails unless it's already enabled
72 * with the same STU on the PF.
73 */
74 ctrl = PCI_ATS_CTRL_ENABLE;
75 if (dev->is_virtfn) {
76 pdev = pci_physfn(dev);
77 if (pdev->ats_stu != ps)
78 return -EINVAL;
79 } else {
80 dev->ats_stu = ps;
81 ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
82 }
83 pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
84
85 dev->ats_enabled = 1;
86 return 0;
87}
88EXPORT_SYMBOL_GPL(pci_enable_ats);
89
90/**
91 * pci_disable_ats - disable the ATS capability
92 * @dev: the PCI device
93 */
94void pci_disable_ats(struct pci_dev *dev)
95{
96 u16 ctrl;
97
98 if (WARN_ON(!dev->ats_enabled))
99 return;
100
101 pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, &ctrl);
102 ctrl &= ~PCI_ATS_CTRL_ENABLE;
103 pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
104
105 dev->ats_enabled = 0;
106}
107EXPORT_SYMBOL_GPL(pci_disable_ats);
108
109void pci_restore_ats_state(struct pci_dev *dev)
110{
111 u16 ctrl;
112
113 if (!dev->ats_enabled)
114 return;
115
116 ctrl = PCI_ATS_CTRL_ENABLE;
117 if (!dev->is_virtfn)
118 ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
119 pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
120}
121
122/**
123 * pci_ats_queue_depth - query the ATS Invalidate Queue Depth
124 * @dev: the PCI device
125 *
126 * Returns the queue depth on success, or negative on failure.
127 *
128 * The ATS spec uses 0 in the Invalidate Queue Depth field to
129 * indicate that the function can accept 32 Invalidate Request.
130 * But here we use the `real' values (i.e. 1~32) for the Queue
131 * Depth; and 0 indicates the function shares the Queue with
132 * other functions (doesn't exclusively own a Queue).
133 */
134int pci_ats_queue_depth(struct pci_dev *dev)
135{
136 u16 cap;
137
138 if (!dev->ats_cap)
139 return -EINVAL;
140
141 if (dev->is_virtfn)
142 return 0;
143
144 pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CAP, &cap);
145 return PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) : PCI_ATS_MAX_QDEP;
146}
147
148/**
149 * pci_ats_page_aligned - Return Page Aligned Request bit status.
150 * @pdev: the PCI device
151 *
152 * Returns 1, if the Untranslated Addresses generated by the device
153 * are always aligned or 0 otherwise.
154 *
155 * Per PCIe spec r4.0, sec 10.5.1.2, if the Page Aligned Request bit
156 * is set, it indicates the Untranslated Addresses generated by the
157 * device are always aligned to a 4096 byte boundary.
158 */
159int pci_ats_page_aligned(struct pci_dev *pdev)
160{
161 u16 cap;
162
163 if (!pdev->ats_cap)
164 return 0;
165
166 pci_read_config_word(pdev, pdev->ats_cap + PCI_ATS_CAP, &cap);
167
168 if (cap & PCI_ATS_CAP_PAGE_ALIGNED)
169 return 1;
170
171 return 0;
172}
173
174#ifdef CONFIG_PCI_PRI
175void pci_pri_init(struct pci_dev *pdev)
176{
177 u16 status;
178
179 pdev->pri_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
180
181 if (!pdev->pri_cap)
182 return;
183
184 pci_read_config_word(pdev, pdev->pri_cap + PCI_PRI_STATUS, &status);
185 if (status & PCI_PRI_STATUS_PASID)
186 pdev->pasid_required = 1;
187}
188
189/**
190 * pci_enable_pri - Enable PRI capability
191 * @pdev: PCI device structure
192 * @reqs: outstanding requests
193 *
194 * Returns 0 on success, negative value on error
195 */
196int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
197{
198 u16 control, status;
199 u32 max_requests;
200 int pri = pdev->pri_cap;
201
202 /*
203 * VFs must not implement the PRI Capability. If their PF
204 * implements PRI, it is shared by the VFs, so if the PF PRI is
205 * enabled, it is also enabled for the VF.
206 */
207 if (pdev->is_virtfn) {
208 if (pci_physfn(pdev)->pri_enabled)
209 return 0;
210 return -EINVAL;
211 }
212
213 if (WARN_ON(pdev->pri_enabled))
214 return -EBUSY;
215
216 if (!pri)
217 return -EINVAL;
218
219 pci_read_config_word(pdev, pri + PCI_PRI_STATUS, &status);
220 if (!(status & PCI_PRI_STATUS_STOPPED))
221 return -EBUSY;
222
223 pci_read_config_dword(pdev, pri + PCI_PRI_MAX_REQ, &max_requests);
224 reqs = min(max_requests, reqs);
225 pdev->pri_reqs_alloc = reqs;
226 pci_write_config_dword(pdev, pri + PCI_PRI_ALLOC_REQ, reqs);
227
228 control = PCI_PRI_CTRL_ENABLE;
229 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
230
231 pdev->pri_enabled = 1;
232
233 return 0;
234}
235
236/**
237 * pci_disable_pri - Disable PRI capability
238 * @pdev: PCI device structure
239 *
240 * Only clears the enabled-bit, regardless of its former value
241 */
242void pci_disable_pri(struct pci_dev *pdev)
243{
244 u16 control;
245 int pri = pdev->pri_cap;
246
247 /* VFs share the PF PRI */
248 if (pdev->is_virtfn)
249 return;
250
251 if (WARN_ON(!pdev->pri_enabled))
252 return;
253
254 if (!pri)
255 return;
256
257 pci_read_config_word(pdev, pri + PCI_PRI_CTRL, &control);
258 control &= ~PCI_PRI_CTRL_ENABLE;
259 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
260
261 pdev->pri_enabled = 0;
262}
263EXPORT_SYMBOL_GPL(pci_disable_pri);
264
265/**
266 * pci_restore_pri_state - Restore PRI
267 * @pdev: PCI device structure
268 */
269void pci_restore_pri_state(struct pci_dev *pdev)
270{
271 u16 control = PCI_PRI_CTRL_ENABLE;
272 u32 reqs = pdev->pri_reqs_alloc;
273 int pri = pdev->pri_cap;
274
275 if (pdev->is_virtfn)
276 return;
277
278 if (!pdev->pri_enabled)
279 return;
280
281 if (!pri)
282 return;
283
284 pci_write_config_dword(pdev, pri + PCI_PRI_ALLOC_REQ, reqs);
285 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
286}
287
288/**
289 * pci_reset_pri - Resets device's PRI state
290 * @pdev: PCI device structure
291 *
292 * The PRI capability must be disabled before this function is called.
293 * Returns 0 on success, negative value on error.
294 */
295int pci_reset_pri(struct pci_dev *pdev)
296{
297 u16 control;
298 int pri = pdev->pri_cap;
299
300 if (pdev->is_virtfn)
301 return 0;
302
303 if (WARN_ON(pdev->pri_enabled))
304 return -EBUSY;
305
306 if (!pri)
307 return -EINVAL;
308
309 control = PCI_PRI_CTRL_RESET;
310 pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
311
312 return 0;
313}
314
315/**
316 * pci_prg_resp_pasid_required - Return PRG Response PASID Required bit
317 * status.
318 * @pdev: PCI device structure
319 *
320 * Returns 1 if PASID is required in PRG Response Message, 0 otherwise.
321 */
322int pci_prg_resp_pasid_required(struct pci_dev *pdev)
323{
324 if (pdev->is_virtfn)
325 pdev = pci_physfn(pdev);
326
327 return pdev->pasid_required;
328}
329
330/**
331 * pci_pri_supported - Check if PRI is supported.
332 * @pdev: PCI device structure
333 *
334 * Returns true if PRI capability is present, false otherwise.
335 */
336bool pci_pri_supported(struct pci_dev *pdev)
337{
338 /* VFs share the PF PRI */
339 if (pci_physfn(pdev)->pri_cap)
340 return true;
341 return false;
342}
343EXPORT_SYMBOL_GPL(pci_pri_supported);
344#endif /* CONFIG_PCI_PRI */
345
346#ifdef CONFIG_PCI_PASID
347void pci_pasid_init(struct pci_dev *pdev)
348{
349 pdev->pasid_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
350}
351
352/**
353 * pci_enable_pasid - Enable the PASID capability
354 * @pdev: PCI device structure
355 * @features: Features to enable
356 *
357 * Returns 0 on success, negative value on error. This function checks
358 * whether the features are actually supported by the device and returns
359 * an error if not.
360 */
361int pci_enable_pasid(struct pci_dev *pdev, int features)
362{
363 u16 control, supported;
364 int pasid = pdev->pasid_cap;
365
366 /*
367 * VFs must not implement the PASID Capability, but if a PF
368 * supports PASID, its VFs share the PF PASID configuration.
369 */
370 if (pdev->is_virtfn) {
371 if (pci_physfn(pdev)->pasid_enabled)
372 return 0;
373 return -EINVAL;
374 }
375
376 if (WARN_ON(pdev->pasid_enabled))
377 return -EBUSY;
378
379 if (!pdev->eetlp_prefix_path)
380 return -EINVAL;
381
382 if (!pasid)
383 return -EINVAL;
384
385 pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
386 supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
387
388 /* User wants to enable anything unsupported? */
389 if ((supported & features) != features)
390 return -EINVAL;
391
392 control = PCI_PASID_CTRL_ENABLE | features;
393 pdev->pasid_features = features;
394
395 pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
396
397 pdev->pasid_enabled = 1;
398
399 return 0;
400}
401EXPORT_SYMBOL_GPL(pci_enable_pasid);
402
403/**
404 * pci_disable_pasid - Disable the PASID capability
405 * @pdev: PCI device structure
406 */
407void pci_disable_pasid(struct pci_dev *pdev)
408{
409 u16 control = 0;
410 int pasid = pdev->pasid_cap;
411
412 /* VFs share the PF PASID configuration */
413 if (pdev->is_virtfn)
414 return;
415
416 if (WARN_ON(!pdev->pasid_enabled))
417 return;
418
419 if (!pasid)
420 return;
421
422 pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
423
424 pdev->pasid_enabled = 0;
425}
426EXPORT_SYMBOL_GPL(pci_disable_pasid);
427
428/**
429 * pci_restore_pasid_state - Restore PASID capabilities
430 * @pdev: PCI device structure
431 */
432void pci_restore_pasid_state(struct pci_dev *pdev)
433{
434 u16 control;
435 int pasid = pdev->pasid_cap;
436
437 if (pdev->is_virtfn)
438 return;
439
440 if (!pdev->pasid_enabled)
441 return;
442
443 if (!pasid)
444 return;
445
446 control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features;
447 pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
448}
449
450/**
451 * pci_pasid_features - Check which PASID features are supported
452 * @pdev: PCI device structure
453 *
454 * Returns a negative value when no PASI capability is present.
455 * Otherwise is returns a bitmask with supported features. Current
456 * features reported are:
457 * PCI_PASID_CAP_EXEC - Execute permission supported
458 * PCI_PASID_CAP_PRIV - Privileged mode supported
459 */
460int pci_pasid_features(struct pci_dev *pdev)
461{
462 u16 supported;
463 int pasid;
464
465 if (pdev->is_virtfn)
466 pdev = pci_physfn(pdev);
467
468 pasid = pdev->pasid_cap;
469 if (!pasid)
470 return -EINVAL;
471
472 pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
473
474 supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
475
476 return supported;
477}
478EXPORT_SYMBOL_GPL(pci_pasid_features);
479
480#define PASID_NUMBER_SHIFT 8
481#define PASID_NUMBER_MASK (0x1f << PASID_NUMBER_SHIFT)
482/**
483 * pci_max_pasid - Get maximum number of PASIDs supported by device
484 * @pdev: PCI device structure
485 *
486 * Returns negative value when PASID capability is not present.
487 * Otherwise it returns the number of supported PASIDs.
488 */
489int pci_max_pasids(struct pci_dev *pdev)
490{
491 u16 supported;
492 int pasid;
493
494 if (pdev->is_virtfn)
495 pdev = pci_physfn(pdev);
496
497 pasid = pdev->pasid_cap;
498 if (!pasid)
499 return -EINVAL;
500
501 pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
502
503 supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT;
504
505 return (1 << supported);
506}
507EXPORT_SYMBOL_GPL(pci_max_pasids);
508#endif /* CONFIG_PCI_PASID */