xref: /openbmc/qemu/hw/pci/pcie.c (revision b8116f4c)
1 /*
2  * pcie.c
3  *
4  * Copyright (c) 2010 Isaku Yamahata <yamahata at valinux co jp>
5  *                    VA Linux Systems Japan K.K.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License along
18  * with this program; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qapi/error.h"
23 #include "hw/pci/pci_bridge.h"
24 #include "hw/pci/pcie.h"
25 #include "hw/pci/msix.h"
26 #include "hw/pci/msi.h"
27 #include "hw/pci/pci_bus.h"
28 #include "hw/pci/pcie_regs.h"
29 #include "hw/pci/pcie_port.h"
30 #include "qemu/range.h"
31 #include "trace.h"
32 
33 //#define DEBUG_PCIE
34 #ifdef DEBUG_PCIE
35 # define PCIE_DPRINTF(fmt, ...)                                         \
36     fprintf(stderr, "%s:%d " fmt, __func__, __LINE__, ## __VA_ARGS__)
37 #else
38 # define PCIE_DPRINTF(fmt, ...) do {} while (0)
39 #endif
40 #define PCIE_DEV_PRINTF(dev, fmt, ...)                                  \
41     PCIE_DPRINTF("%s:%x "fmt, (dev)->name, (dev)->devfn, ## __VA_ARGS__)
42 
43 static bool pcie_sltctl_powered_off(uint16_t sltctl)
44 {
45     return (sltctl & PCI_EXP_SLTCTL_PCC) == PCI_EXP_SLTCTL_PWR_OFF
46         && (sltctl & PCI_EXP_SLTCTL_PIC) == PCI_EXP_SLTCTL_PWR_IND_OFF;
47 }
48 
49 static const char *pcie_led_state_to_str(uint16_t value)
50 {
51     switch (value) {
52     case PCI_EXP_SLTCTL_PWR_IND_ON:
53     case PCI_EXP_SLTCTL_ATTN_IND_ON:
54         return "on";
55     case PCI_EXP_SLTCTL_PWR_IND_BLINK:
56     case PCI_EXP_SLTCTL_ATTN_IND_BLINK:
57         return "blink";
58     case PCI_EXP_SLTCTL_PWR_IND_OFF:
59     case PCI_EXP_SLTCTL_ATTN_IND_OFF:
60         return "off";
61     default:
62         return "invalid";
63     }
64 }
65 
66 /***************************************************************************
67  * pci express capability helper functions
68  */
69 
70 static void
71 pcie_cap_v1_fill(PCIDevice *dev, uint8_t port, uint8_t type, uint8_t version)
72 {
73     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
74     uint8_t *cmask = dev->cmask + dev->exp.exp_cap;
75 
76     /* capability register
77     interrupt message number defaults to 0 */
78     pci_set_word(exp_cap + PCI_EXP_FLAGS,
79                  ((type << PCI_EXP_FLAGS_TYPE_SHIFT) & PCI_EXP_FLAGS_TYPE) |
80                  version);
81 
82     /* device capability register
83      * table 7-12:
84      * roll based error reporting bit must be set by all
85      * Functions conforming to the ECN, PCI Express Base
86      * Specification, Revision 1.1., or subsequent PCI Express Base
87      * Specification revisions.
88      */
89     pci_set_long(exp_cap + PCI_EXP_DEVCAP, PCI_EXP_DEVCAP_RBER);
90 
91     pci_set_long(exp_cap + PCI_EXP_LNKCAP,
92                  (port << PCI_EXP_LNKCAP_PN_SHIFT) |
93                  PCI_EXP_LNKCAP_ASPMS_0S |
94                  QEMU_PCI_EXP_LNKCAP_MLW(QEMU_PCI_EXP_LNK_X1) |
95                  QEMU_PCI_EXP_LNKCAP_MLS(QEMU_PCI_EXP_LNK_2_5GT));
96 
97     pci_set_word(exp_cap + PCI_EXP_LNKSTA,
98                  QEMU_PCI_EXP_LNKSTA_NLW(QEMU_PCI_EXP_LNK_X1) |
99                  QEMU_PCI_EXP_LNKSTA_CLS(QEMU_PCI_EXP_LNK_2_5GT));
100 
101     /* We changed link status bits over time, and changing them across
102      * migrations is generally fine as hardware changes them too.
103      * Let's not bother checking.
104      */
105     pci_set_word(cmask + PCI_EXP_LNKSTA, 0);
106 }
107 
108 static void pcie_cap_fill_slot_lnk(PCIDevice *dev)
109 {
110     PCIESlot *s = (PCIESlot *)object_dynamic_cast(OBJECT(dev), TYPE_PCIE_SLOT);
111     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
112 
113     /* Skip anything that isn't a PCIESlot */
114     if (!s) {
115         return;
116     }
117 
118     /* Clear and fill LNKCAP from what was configured above */
119     pci_long_test_and_clear_mask(exp_cap + PCI_EXP_LNKCAP,
120                                  PCI_EXP_LNKCAP_MLW | PCI_EXP_LNKCAP_SLS);
121     pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP,
122                                QEMU_PCI_EXP_LNKCAP_MLW(s->width) |
123                                QEMU_PCI_EXP_LNKCAP_MLS(s->speed));
124 
125     /*
126      * Link bandwidth notification is required for all root ports and
127      * downstream ports supporting links wider than x1 or multiple link
128      * speeds.
129      */
130     if (s->width > QEMU_PCI_EXP_LNK_X1 ||
131         s->speed > QEMU_PCI_EXP_LNK_2_5GT) {
132         pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP,
133                                    PCI_EXP_LNKCAP_LBNC);
134     }
135 
136     if (s->speed > QEMU_PCI_EXP_LNK_2_5GT) {
137         /*
138          * Hot-plug capable downstream ports and downstream ports supporting
139          * link speeds greater than 5GT/s must hardwire PCI_EXP_LNKCAP_DLLLARC
140          * to 1b.  PCI_EXP_LNKCAP_DLLLARC implies PCI_EXP_LNKSTA_DLLLA, which
141          * we also hardwire to 1b here.  2.5GT/s hot-plug slots should also
142          * technically implement this, but it's not done here for compatibility.
143          */
144         pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP,
145                                    PCI_EXP_LNKCAP_DLLLARC);
146         /* the PCI_EXP_LNKSTA_DLLLA will be set in the hotplug function */
147 
148         /*
149          * Target Link Speed defaults to the highest link speed supported by
150          * the component.  2.5GT/s devices are permitted to hardwire to zero.
151          */
152         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKCTL2,
153                                      PCI_EXP_LNKCTL2_TLS);
154         pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKCTL2,
155                                    QEMU_PCI_EXP_LNKCAP_MLS(s->speed) &
156                                    PCI_EXP_LNKCTL2_TLS);
157     }
158 
159     /*
160      * 2.5 & 5.0GT/s can be fully described by LNKCAP, but 8.0GT/s is
161      * actually a reference to the highest bit supported in this register.
162      * We assume the device supports all link speeds.
163      */
164     if (s->speed > QEMU_PCI_EXP_LNK_5GT) {
165         pci_long_test_and_clear_mask(exp_cap + PCI_EXP_LNKCAP2, ~0U);
166         pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP2,
167                                    PCI_EXP_LNKCAP2_SLS_2_5GB |
168                                    PCI_EXP_LNKCAP2_SLS_5_0GB |
169                                    PCI_EXP_LNKCAP2_SLS_8_0GB);
170         if (s->speed > QEMU_PCI_EXP_LNK_8GT) {
171             pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP2,
172                                        PCI_EXP_LNKCAP2_SLS_16_0GB);
173         }
174         if (s->speed > QEMU_PCI_EXP_LNK_16GT) {
175             pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP2,
176                                        PCI_EXP_LNKCAP2_SLS_32_0GB);
177         }
178         if (s->speed > QEMU_PCI_EXP_LNK_32GT) {
179             pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP2,
180                                        PCI_EXP_LNKCAP2_SLS_64_0GB);
181         }
182     }
183 }
184 
185 int pcie_cap_init(PCIDevice *dev, uint8_t offset,
186                   uint8_t type, uint8_t port,
187                   Error **errp)
188 {
189     /* PCIe cap v2 init */
190     int pos;
191     uint8_t *exp_cap;
192 
193     assert(pci_is_express(dev));
194 
195     pos = pci_add_capability(dev, PCI_CAP_ID_EXP, offset,
196                              PCI_EXP_VER2_SIZEOF, errp);
197     if (pos < 0) {
198         return pos;
199     }
200     dev->exp.exp_cap = pos;
201     exp_cap = dev->config + pos;
202 
203     /* Filling values common with v1 */
204     pcie_cap_v1_fill(dev, port, type, PCI_EXP_FLAGS_VER2);
205 
206     /* Fill link speed and width options */
207     pcie_cap_fill_slot_lnk(dev);
208 
209     /* Filling v2 specific values */
210     pci_set_long(exp_cap + PCI_EXP_DEVCAP2,
211                  PCI_EXP_DEVCAP2_EFF | PCI_EXP_DEVCAP2_EETLPP);
212 
213     pci_set_word(dev->wmask + pos + PCI_EXP_DEVCTL2, PCI_EXP_DEVCTL2_EETLPPB);
214 
215     if (dev->cap_present & QEMU_PCIE_EXTCAP_INIT) {
216         /* read-only to behave like a 'NULL' Extended Capability Header */
217         pci_set_long(dev->wmask + PCI_CONFIG_SPACE_SIZE, 0);
218     }
219 
220     return pos;
221 }
222 
223 int pcie_cap_v1_init(PCIDevice *dev, uint8_t offset, uint8_t type,
224                      uint8_t port)
225 {
226     /* PCIe cap v1 init */
227     int pos;
228     Error *local_err = NULL;
229 
230     assert(pci_is_express(dev));
231 
232     pos = pci_add_capability(dev, PCI_CAP_ID_EXP, offset,
233                              PCI_EXP_VER1_SIZEOF, &local_err);
234     if (pos < 0) {
235         error_report_err(local_err);
236         return pos;
237     }
238     dev->exp.exp_cap = pos;
239 
240     pcie_cap_v1_fill(dev, port, type, PCI_EXP_FLAGS_VER1);
241 
242     return pos;
243 }
244 
245 static int
246 pcie_endpoint_cap_common_init(PCIDevice *dev, uint8_t offset, uint8_t cap_size)
247 {
248     uint8_t type = PCI_EXP_TYPE_ENDPOINT;
249     Error *local_err = NULL;
250     int ret;
251 
252     /*
253      * Windows guests will report Code 10, device cannot start, if
254      * a regular Endpoint type is exposed on a root complex.  These
255      * should instead be Root Complex Integrated Endpoints.
256      */
257     if (pci_bus_is_express(pci_get_bus(dev))
258         && pci_bus_is_root(pci_get_bus(dev))) {
259         type = PCI_EXP_TYPE_RC_END;
260     }
261 
262     if (cap_size == PCI_EXP_VER1_SIZEOF) {
263         return pcie_cap_v1_init(dev, offset, type, 0);
264     } else {
265         ret = pcie_cap_init(dev, offset, type, 0, &local_err);
266 
267         if (ret < 0) {
268             error_report_err(local_err);
269         }
270 
271         return ret;
272     }
273 }
274 
275 int pcie_endpoint_cap_init(PCIDevice *dev, uint8_t offset)
276 {
277     return pcie_endpoint_cap_common_init(dev, offset, PCI_EXP_VER2_SIZEOF);
278 }
279 
280 int pcie_endpoint_cap_v1_init(PCIDevice *dev, uint8_t offset)
281 {
282     return pcie_endpoint_cap_common_init(dev, offset, PCI_EXP_VER1_SIZEOF);
283 }
284 
285 void pcie_cap_exit(PCIDevice *dev)
286 {
287     pci_del_capability(dev, PCI_CAP_ID_EXP, PCI_EXP_VER2_SIZEOF);
288 }
289 
290 void pcie_cap_v1_exit(PCIDevice *dev)
291 {
292     pci_del_capability(dev, PCI_CAP_ID_EXP, PCI_EXP_VER1_SIZEOF);
293 }
294 
295 uint8_t pcie_cap_get_type(const PCIDevice *dev)
296 {
297     uint32_t pos = dev->exp.exp_cap;
298     assert(pos > 0);
299     return (pci_get_word(dev->config + pos + PCI_EXP_FLAGS) &
300             PCI_EXP_FLAGS_TYPE) >> PCI_EXP_FLAGS_TYPE_SHIFT;
301 }
302 
303 uint8_t pcie_cap_get_version(const PCIDevice *dev)
304 {
305     uint32_t pos = dev->exp.exp_cap;
306     assert(pos > 0);
307     return pci_get_word(dev->config + pos + PCI_EXP_FLAGS) & PCI_EXP_FLAGS_VERS;
308 }
309 
310 /* MSI/MSI-X */
311 /* pci express interrupt message number */
312 /* 7.8.2 PCI Express Capabilities Register: Interrupt Message Number */
313 void pcie_cap_flags_set_vector(PCIDevice *dev, uint8_t vector)
314 {
315     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
316     assert(vector < 32);
317     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_FLAGS, PCI_EXP_FLAGS_IRQ);
318     pci_word_test_and_set_mask(exp_cap + PCI_EXP_FLAGS,
319                                vector << PCI_EXP_FLAGS_IRQ_SHIFT);
320 }
321 
322 uint8_t pcie_cap_flags_get_vector(PCIDevice *dev)
323 {
324     return (pci_get_word(dev->config + dev->exp.exp_cap + PCI_EXP_FLAGS) &
325             PCI_EXP_FLAGS_IRQ) >> PCI_EXP_FLAGS_IRQ_SHIFT;
326 }
327 
328 void pcie_cap_deverr_init(PCIDevice *dev)
329 {
330     uint32_t pos = dev->exp.exp_cap;
331     pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_DEVCAP,
332                                PCI_EXP_DEVCAP_RBER);
333     pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_DEVCTL,
334                                PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE |
335                                PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE);
336     pci_long_test_and_set_mask(dev->w1cmask + pos + PCI_EXP_DEVSTA,
337                                PCI_EXP_DEVSTA_CED | PCI_EXP_DEVSTA_NFED |
338                                PCI_EXP_DEVSTA_FED | PCI_EXP_DEVSTA_URD);
339 }
340 
341 void pcie_cap_deverr_reset(PCIDevice *dev)
342 {
343     uint8_t *devctl = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL;
344     pci_long_test_and_clear_mask(devctl,
345                                  PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE |
346                                  PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE);
347 }
348 
349 void pcie_cap_lnkctl_init(PCIDevice *dev)
350 {
351     uint32_t pos = dev->exp.exp_cap;
352     pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_LNKCTL,
353                                PCI_EXP_LNKCTL_CCC | PCI_EXP_LNKCTL_ES);
354 }
355 
356 void pcie_cap_lnkctl_reset(PCIDevice *dev)
357 {
358     uint8_t *lnkctl = dev->config + dev->exp.exp_cap + PCI_EXP_LNKCTL;
359     pci_long_test_and_clear_mask(lnkctl,
360                                  PCI_EXP_LNKCTL_CCC | PCI_EXP_LNKCTL_ES);
361 }
362 
363 static void hotplug_event_update_event_status(PCIDevice *dev)
364 {
365     uint32_t pos = dev->exp.exp_cap;
366     uint8_t *exp_cap = dev->config + pos;
367     uint16_t sltctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
368     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
369 
370     dev->exp.hpev_notified = (sltctl & PCI_EXP_SLTCTL_HPIE) &&
371         (sltsta & sltctl & PCI_EXP_HP_EV_SUPPORTED);
372 }
373 
374 static void hotplug_event_notify(PCIDevice *dev)
375 {
376     bool prev = dev->exp.hpev_notified;
377 
378     hotplug_event_update_event_status(dev);
379 
380     if (prev == dev->exp.hpev_notified) {
381         return;
382     }
383 
384     /* Note: the logic above does not take into account whether interrupts
385      * are masked. The result is that interrupt will be sent when it is
386      * subsequently unmasked. This appears to be legal: Section 6.7.3.4:
387      * The Port may optionally send an MSI when there are hot-plug events that
388      * occur while interrupt generation is disabled, and interrupt generation is
389      * subsequently enabled. */
390     if (msix_enabled(dev)) {
391         msix_notify(dev, pcie_cap_flags_get_vector(dev));
392     } else if (msi_enabled(dev)) {
393         msi_notify(dev, pcie_cap_flags_get_vector(dev));
394     } else if (pci_intx(dev) != -1) {
395         pci_set_irq(dev, dev->exp.hpev_notified);
396     }
397 }
398 
399 static void hotplug_event_clear(PCIDevice *dev)
400 {
401     hotplug_event_update_event_status(dev);
402     if (!msix_enabled(dev) && !msi_enabled(dev) && pci_intx(dev) != -1 &&
403         !dev->exp.hpev_notified) {
404         pci_irq_deassert(dev);
405     }
406 }
407 
408 void pcie_cap_slot_enable_power(PCIDevice *dev)
409 {
410     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
411     uint32_t sltcap = pci_get_long(exp_cap + PCI_EXP_SLTCAP);
412 
413     if (sltcap & PCI_EXP_SLTCAP_PCP) {
414         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,
415                                      PCI_EXP_SLTCTL_PCC);
416     }
417 }
418 
419 static void pcie_set_power_device(PCIBus *bus, PCIDevice *dev, void *opaque)
420 {
421     bool *power = opaque;
422 
423     pci_set_power(dev, *power);
424 }
425 
426 static void pcie_cap_update_power(PCIDevice *hotplug_dev)
427 {
428     uint8_t *exp_cap = hotplug_dev->config + hotplug_dev->exp.exp_cap;
429     PCIBus *sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(hotplug_dev));
430     uint32_t sltcap = pci_get_long(exp_cap + PCI_EXP_SLTCAP);
431     uint16_t sltctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
432     bool power = true;
433 
434     if (sltcap & PCI_EXP_SLTCAP_PCP) {
435         power = (sltctl & PCI_EXP_SLTCTL_PCC) == PCI_EXP_SLTCTL_PWR_ON;
436         /* Don't we need to check also (sltctl & PCI_EXP_SLTCTL_PIC) ? */
437     }
438 
439     pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
440                         pcie_set_power_device, &power);
441 }
442 
443 /*
444  * A PCI Express Hot-Plug Event has occurred, so update slot status register
445  * and notify OS of the event if necessary.
446  *
447  * 6.7.3 PCI Express Hot-Plug Events
448  * 6.7.3.4 Software Notification of Hot-Plug Events
449  */
450 static void pcie_cap_slot_event(PCIDevice *dev, PCIExpressHotPlugEvent event)
451 {
452     /* Minor optimization: if nothing changed - no event is needed. */
453     if (pci_word_test_and_set_mask(dev->config + dev->exp.exp_cap +
454                                    PCI_EXP_SLTSTA, event) == event) {
455         return;
456     }
457     hotplug_event_notify(dev);
458 }
459 
460 static void pcie_cap_slot_plug_common(PCIDevice *hotplug_dev, DeviceState *dev,
461                                       Error **errp)
462 {
463     uint8_t *exp_cap = hotplug_dev->config + hotplug_dev->exp.exp_cap;
464     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
465 
466     PCIE_DEV_PRINTF(PCI_DEVICE(dev), "hotplug state: 0x%x\n", sltsta);
467     if (sltsta & PCI_EXP_SLTSTA_EIS) {
468         /* the slot is electromechanically locked.
469          * This error is propagated up to qdev and then to HMP/QMP.
470          */
471         error_setg_errno(errp, EBUSY, "slot is electromechanically locked");
472     }
473 }
474 
475 void pcie_cap_slot_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
476                                Error **errp)
477 {
478     PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev);
479     uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap;
480     uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP);
481 
482     /* Check if hot-plug is disabled on the slot */
483     if (dev->hotplugged && (sltcap & PCI_EXP_SLTCAP_HPC) == 0) {
484         error_setg(errp, "Hot-plug failed: unsupported by the port device '%s'",
485                          DEVICE(hotplug_pdev)->id);
486         return;
487     }
488 
489     pcie_cap_slot_plug_common(PCI_DEVICE(hotplug_dev), dev, errp);
490 }
491 
492 void pcie_cap_slot_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
493                            Error **errp)
494 {
495     PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev);
496     uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap;
497     PCIDevice *pci_dev = PCI_DEVICE(dev);
498     uint32_t lnkcap = pci_get_long(exp_cap + PCI_EXP_LNKCAP);
499 
500     if (pci_is_vf(pci_dev)) {
501         /* Virtual function cannot be physically disconnected */
502         return;
503     }
504 
505     /* Don't send event when device is enabled during qemu machine creation:
506      * it is present on boot, no hotplug event is necessary. We do send an
507      * event when the device is disabled later. */
508     if (!dev->hotplugged) {
509         pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,
510                                    PCI_EXP_SLTSTA_PDS);
511         if (pci_dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA ||
512             (lnkcap & PCI_EXP_LNKCAP_DLLLARC)) {
513             pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA,
514                                        PCI_EXP_LNKSTA_DLLLA);
515         }
516         pcie_cap_update_power(hotplug_pdev);
517         return;
518     }
519 
520     /* To enable multifunction hot-plug, we just ensure the function
521      * 0 added last. When function 0 is added, we set the sltsta and
522      * inform OS via event notification.
523      */
524     if (pci_get_function_0(pci_dev)) {
525         pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,
526                                    PCI_EXP_SLTSTA_PDS);
527         if (pci_dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA ||
528             (lnkcap & PCI_EXP_LNKCAP_DLLLARC)) {
529             pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA,
530                                        PCI_EXP_LNKSTA_DLLLA);
531         }
532         pcie_cap_slot_event(hotplug_pdev,
533                             PCI_EXP_HP_EV_PDC | PCI_EXP_HP_EV_ABP);
534         pcie_cap_update_power(hotplug_pdev);
535     }
536 }
537 
538 void pcie_cap_slot_unplug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
539                              Error **errp)
540 {
541     qdev_unrealize(dev);
542 }
543 
544 static void pcie_unplug_device(PCIBus *bus, PCIDevice *dev, void *opaque)
545 {
546     HotplugHandler *hotplug_ctrl = qdev_get_hotplug_handler(DEVICE(dev));
547 
548     if (dev->partially_hotplugged) {
549         dev->qdev.pending_deleted_event = false;
550         return;
551     }
552     hotplug_handler_unplug(hotplug_ctrl, DEVICE(dev), &error_abort);
553     object_unparent(OBJECT(dev));
554 }
555 
556 static void pcie_cap_slot_do_unplug(PCIDevice *dev)
557 {
558     PCIBus *sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(dev));
559     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
560     uint32_t lnkcap = pci_get_long(exp_cap + PCI_EXP_LNKCAP);
561 
562     pci_for_each_device_under_bus(sec_bus, pcie_unplug_device, NULL);
563 
564     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
565                                  PCI_EXP_SLTSTA_PDS);
566     if (dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA ||
567         (lnkcap & PCI_EXP_LNKCAP_DLLLARC)) {
568         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKSTA,
569                                      PCI_EXP_LNKSTA_DLLLA);
570     }
571     pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,
572                                PCI_EXP_SLTSTA_PDC);
573 }
574 
575 void pcie_cap_slot_unplug_request_cb(HotplugHandler *hotplug_dev,
576                                      DeviceState *dev, Error **errp)
577 {
578     Error *local_err = NULL;
579     PCIDevice *pci_dev = PCI_DEVICE(dev);
580     PCIBus *bus = pci_get_bus(pci_dev);
581     PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev);
582     uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap;
583     uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP);
584     uint16_t sltctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
585 
586     /* Check if hot-unplug is disabled on the slot */
587     if ((sltcap & PCI_EXP_SLTCAP_HPC) == 0) {
588         error_setg(errp, "Hot-unplug failed: "
589                          "unsupported by the port device '%s'",
590                          DEVICE(hotplug_pdev)->id);
591         return;
592     }
593 
594     pcie_cap_slot_plug_common(hotplug_pdev, dev, &local_err);
595     if (local_err) {
596         error_propagate(errp, local_err);
597         return;
598     }
599 
600     if ((sltctl & PCI_EXP_SLTCTL_PIC) == PCI_EXP_SLTCTL_PWR_IND_BLINK) {
601         error_setg(errp, "Hot-unplug failed: "
602                    "guest is busy (power indicator blinking)");
603         return;
604     }
605 
606     dev->pending_deleted_event = true;
607     dev->pending_deleted_expires_ms =
608         qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 5000; /* 5 secs */
609 
610     /* In case user cancel the operation of multi-function hot-add,
611      * remove the function that is unexposed to guest individually,
612      * without interaction with guest.
613      */
614     if (pci_dev->devfn &&
615         !bus->devices[0]) {
616         pcie_unplug_device(bus, pci_dev, NULL);
617 
618         return;
619     }
620 
621     if (pcie_sltctl_powered_off(sltctl)) {
622         /* slot is powered off -> unplug without round-trip to the guest */
623         pcie_cap_slot_do_unplug(hotplug_pdev);
624         hotplug_event_notify(hotplug_pdev);
625         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
626                                      PCI_EXP_SLTSTA_ABP);
627         return;
628     }
629 
630     pcie_cap_slot_push_attention_button(hotplug_pdev);
631 }
632 
633 /* pci express slot for pci express root/downstream port
634    PCI express capability slot registers */
635 void pcie_cap_slot_init(PCIDevice *dev, PCIESlot *s)
636 {
637     uint32_t pos = dev->exp.exp_cap;
638 
639     pci_word_test_and_set_mask(dev->config + pos + PCI_EXP_FLAGS,
640                                PCI_EXP_FLAGS_SLOT);
641 
642     pci_long_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCAP,
643                                  ~PCI_EXP_SLTCAP_PSN);
644     pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
645                                (s->slot << PCI_EXP_SLTCAP_PSN_SHIFT) |
646                                PCI_EXP_SLTCAP_EIP |
647                                PCI_EXP_SLTCAP_PIP |
648                                PCI_EXP_SLTCAP_AIP |
649                                PCI_EXP_SLTCAP_ABP);
650 
651     /*
652      * Expose native hot-plug on all bridges if hot-plug is enabled on the slot.
653      * (unless broken 6.1 ABI is enforced for compat reasons)
654      */
655     if (s->hotplug &&
656         (!s->hide_native_hotplug_cap || DEVICE(dev)->hotplugged)) {
657         pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
658                                    PCI_EXP_SLTCAP_HPS |
659                                    PCI_EXP_SLTCAP_HPC);
660     }
661 
662     if (dev->cap_present & QEMU_PCIE_SLTCAP_PCP) {
663         pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
664                                    PCI_EXP_SLTCAP_PCP);
665         pci_word_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCTL,
666                                      PCI_EXP_SLTCTL_PCC);
667         pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,
668                                    PCI_EXP_SLTCTL_PCC);
669     }
670 
671     pci_word_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCTL,
672                                  PCI_EXP_SLTCTL_PIC |
673                                  PCI_EXP_SLTCTL_AIC);
674     pci_word_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCTL,
675                                PCI_EXP_SLTCTL_PWR_IND_OFF |
676                                PCI_EXP_SLTCTL_ATTN_IND_OFF);
677     pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,
678                                PCI_EXP_SLTCTL_PIC |
679                                PCI_EXP_SLTCTL_AIC |
680                                PCI_EXP_SLTCTL_HPIE |
681                                PCI_EXP_SLTCTL_CCIE |
682                                PCI_EXP_SLTCTL_PDCE |
683                                PCI_EXP_SLTCTL_ABPE);
684     /* Although reading PCI_EXP_SLTCTL_EIC returns always 0,
685      * make the bit writable here in order to detect 1b is written.
686      * pcie_cap_slot_write_config() test-and-clear the bit, so
687      * this bit always returns 0 to the guest.
688      */
689     pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,
690                                PCI_EXP_SLTCTL_EIC);
691 
692     pci_word_test_and_set_mask(dev->w1cmask + pos + PCI_EXP_SLTSTA,
693                                PCI_EXP_HP_EV_SUPPORTED);
694 
695     /* Avoid migration abortion when this device hot-removed by guest */
696     pci_word_test_and_clear_mask(dev->cmask + pos + PCI_EXP_SLTSTA,
697                                  PCI_EXP_SLTSTA_PDS);
698 
699     dev->exp.hpev_notified = false;
700 
701     qbus_set_hotplug_handler(BUS(pci_bridge_get_sec_bus(PCI_BRIDGE(dev))),
702                              OBJECT(dev));
703 }
704 
705 void pcie_cap_slot_reset(PCIDevice *dev)
706 {
707     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
708     uint8_t port_type = pcie_cap_get_type(dev);
709 
710     assert(port_type == PCI_EXP_TYPE_DOWNSTREAM ||
711            port_type == PCI_EXP_TYPE_ROOT_PORT);
712 
713     PCIE_DEV_PRINTF(dev, "reset\n");
714 
715     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,
716                                  PCI_EXP_SLTCTL_EIC |
717                                  PCI_EXP_SLTCTL_PIC |
718                                  PCI_EXP_SLTCTL_AIC |
719                                  PCI_EXP_SLTCTL_HPIE |
720                                  PCI_EXP_SLTCTL_CCIE |
721                                  PCI_EXP_SLTCTL_PDCE |
722                                  PCI_EXP_SLTCTL_ABPE);
723     pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTCTL,
724                                PCI_EXP_SLTCTL_PWR_IND_OFF |
725                                PCI_EXP_SLTCTL_ATTN_IND_OFF);
726 
727     if (dev->cap_present & QEMU_PCIE_SLTCAP_PCP) {
728         /* Downstream ports enforce device number 0. */
729         bool populated = pci_bridge_get_sec_bus(PCI_BRIDGE(dev))->devices[0];
730         uint16_t pic;
731 
732         if (populated) {
733             pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,
734                                          PCI_EXP_SLTCTL_PCC);
735         } else {
736             pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTCTL,
737                                        PCI_EXP_SLTCTL_PCC);
738         }
739 
740         pic = populated ?
741                 PCI_EXP_SLTCTL_PWR_IND_ON : PCI_EXP_SLTCTL_PWR_IND_OFF;
742         pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTCTL, pic);
743     }
744 
745     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
746                                  PCI_EXP_SLTSTA_EIS |/* on reset,
747                                                         the lock is released */
748                                  PCI_EXP_SLTSTA_CC |
749                                  PCI_EXP_SLTSTA_PDC |
750                                  PCI_EXP_SLTSTA_ABP);
751 
752     pcie_cap_update_power(dev);
753     hotplug_event_update_event_status(dev);
754 }
755 
756 void pcie_cap_slot_get(PCIDevice *dev, uint16_t *slt_ctl, uint16_t *slt_sta)
757 {
758     uint32_t pos = dev->exp.exp_cap;
759     uint8_t *exp_cap = dev->config + pos;
760     *slt_ctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
761     *slt_sta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
762 }
763 
764 static void find_child_fn(PCIBus *bus, PCIDevice *dev, void *opaque)
765 {
766     PCIDevice **child = opaque;
767 
768     if (!*child) {
769         *child = dev;
770     }
771 }
772 
773 /*
774  * Returns the plugged device or first function of multifunction plugged device
775  */
776 static PCIDevice *pcie_cap_slot_find_child(PCIDevice *dev)
777 {
778     PCIBus *sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(dev));
779     PCIDevice *child = NULL;
780 
781     pci_for_each_device(sec_bus, pci_bus_num(sec_bus), find_child_fn, &child);
782 
783     return child;
784 }
785 
786 void pcie_cap_slot_write_config(PCIDevice *dev,
787                                 uint16_t old_slt_ctl, uint16_t old_slt_sta,
788                                 uint32_t addr, uint32_t val, int len)
789 {
790     uint32_t pos = dev->exp.exp_cap;
791     uint8_t *exp_cap = dev->config + pos;
792     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
793 
794     if (ranges_overlap(addr, len, pos + PCI_EXP_SLTSTA, 2)) {
795         /*
796          * Guests tend to clears all bits during init.
797          * If they clear bits that weren't set this is racy and will lose events:
798          * not a big problem for manual button presses, but a problem for us.
799          * As a work-around, detect this and revert status to what it was
800          * before the write.
801          *
802          * Note: in theory this can be detected as a duplicate button press
803          * which cancels the previous press. Does not seem to happen in
804          * practice as guests seem to only have this bug during init.
805          */
806 #define PCIE_SLOT_EVENTS (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD | \
807                           PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC | \
808                           PCI_EXP_SLTSTA_CC)
809 
810         if (val & ~old_slt_sta & PCIE_SLOT_EVENTS) {
811             sltsta = (sltsta & ~PCIE_SLOT_EVENTS) | (old_slt_sta & PCIE_SLOT_EVENTS);
812             pci_set_word(exp_cap + PCI_EXP_SLTSTA, sltsta);
813         }
814         hotplug_event_clear(dev);
815     }
816 
817     if (!ranges_overlap(addr, len, pos + PCI_EXP_SLTCTL, 2)) {
818         return;
819     }
820 
821     if (pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,
822                                      PCI_EXP_SLTCTL_EIC)) {
823         sltsta ^= PCI_EXP_SLTSTA_EIS; /* toggle PCI_EXP_SLTSTA_EIS bit */
824         pci_set_word(exp_cap + PCI_EXP_SLTSTA, sltsta);
825         PCIE_DEV_PRINTF(dev, "PCI_EXP_SLTCTL_EIC: "
826                         "sltsta -> 0x%02"PRIx16"\n",
827                         sltsta);
828     }
829 
830     if (trace_event_get_state_backends(TRACE_PCIE_CAP_SLOT_WRITE_CONFIG)) {
831         DeviceState *parent = DEVICE(dev);
832         DeviceState *child = DEVICE(pcie_cap_slot_find_child(dev));
833 
834         trace_pcie_cap_slot_write_config(
835             parent->canonical_path,
836             child ? child->canonical_path : "no-child",
837             (sltsta & PCI_EXP_SLTSTA_PDS) ? "present" : "not present",
838             pcie_led_state_to_str(old_slt_ctl & PCI_EXP_SLTCTL_PIC),
839             pcie_led_state_to_str(val & PCI_EXP_SLTCTL_PIC),
840             pcie_led_state_to_str(old_slt_ctl & PCI_EXP_SLTCTL_AIC),
841             pcie_led_state_to_str(val & PCI_EXP_SLTCTL_AIC),
842             (old_slt_ctl & PCI_EXP_SLTCTL_PWR_OFF) ? "off" : "on",
843             (val & PCI_EXP_SLTCTL_PWR_OFF) ? "off" : "on");
844     }
845 
846     /*
847      * If the slot is populated, power indicator is off and power
848      * controller is off, it is safe to detach the devices.
849      *
850      * Note: don't detach if condition was already true:
851      * this is a work around for guests that overwrite
852      * control of powered off slots before powering them on.
853      */
854     if ((sltsta & PCI_EXP_SLTSTA_PDS) && pcie_sltctl_powered_off(val) &&
855         !pcie_sltctl_powered_off(old_slt_ctl))
856     {
857         pcie_cap_slot_do_unplug(dev);
858     }
859     pcie_cap_update_power(dev);
860 
861     hotplug_event_notify(dev);
862 
863     /*
864      * 6.7.3.2 Command Completed Events
865      *
866      * Software issues a command to a hot-plug capable Downstream Port by
867      * issuing a write transaction that targets any portion of the Port’s Slot
868      * Control register. A single write to the Slot Control register is
869      * considered to be a single command, even if the write affects more than
870      * one field in the Slot Control register. In response to this transaction,
871      * the Port must carry out the requested actions and then set the
872      * associated status field for the command completed event. */
873 
874     /* Real hardware might take a while to complete requested command because
875      * physical movement would be involved like locking the electromechanical
876      * lock.  However in our case, command is completed instantaneously above,
877      * so send a command completion event right now.
878      */
879     pcie_cap_slot_event(dev, PCI_EXP_HP_EV_CCI);
880 }
881 
882 int pcie_cap_slot_post_load(void *opaque, int version_id)
883 {
884     PCIDevice *dev = opaque;
885     hotplug_event_update_event_status(dev);
886     pcie_cap_update_power(dev);
887     return 0;
888 }
889 
890 void pcie_cap_slot_push_attention_button(PCIDevice *dev)
891 {
892     pcie_cap_slot_event(dev, PCI_EXP_HP_EV_ABP);
893 }
894 
895 /* root control/capabilities/status. PME isn't emulated for now */
896 void pcie_cap_root_init(PCIDevice *dev)
897 {
898     pci_set_word(dev->wmask + dev->exp.exp_cap + PCI_EXP_RTCTL,
899                  PCI_EXP_RTCTL_SECEE | PCI_EXP_RTCTL_SENFEE |
900                  PCI_EXP_RTCTL_SEFEE);
901 }
902 
903 void pcie_cap_root_reset(PCIDevice *dev)
904 {
905     pci_set_word(dev->config + dev->exp.exp_cap + PCI_EXP_RTCTL, 0);
906 }
907 
908 /* function level reset(FLR) */
909 void pcie_cap_flr_init(PCIDevice *dev)
910 {
911     pci_long_test_and_set_mask(dev->config + dev->exp.exp_cap + PCI_EXP_DEVCAP,
912                                PCI_EXP_DEVCAP_FLR);
913 
914     /* Although reading BCR_FLR returns always 0,
915      * the bit is made writable here in order to detect the 1b is written
916      * pcie_cap_flr_write_config() test-and-clear the bit, so
917      * this bit always returns 0 to the guest.
918      */
919     pci_word_test_and_set_mask(dev->wmask + dev->exp.exp_cap + PCI_EXP_DEVCTL,
920                                PCI_EXP_DEVCTL_BCR_FLR);
921 }
922 
923 void pcie_cap_flr_write_config(PCIDevice *dev,
924                                uint32_t addr, uint32_t val, int len)
925 {
926     uint8_t *devctl = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL;
927     if (pci_get_word(devctl) & PCI_EXP_DEVCTL_BCR_FLR) {
928         /* Clear PCI_EXP_DEVCTL_BCR_FLR after invoking the reset handler
929            so the handler can detect FLR by looking at this bit. */
930         pci_device_reset(dev);
931         pci_word_test_and_clear_mask(devctl, PCI_EXP_DEVCTL_BCR_FLR);
932     }
933 }
934 
935 /* Alternative Routing-ID Interpretation (ARI)
936  * forwarding support for root and downstream ports
937  */
938 void pcie_cap_arifwd_init(PCIDevice *dev)
939 {
940     uint32_t pos = dev->exp.exp_cap;
941     pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_DEVCAP2,
942                                PCI_EXP_DEVCAP2_ARI);
943     pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_DEVCTL2,
944                                PCI_EXP_DEVCTL2_ARI);
945 }
946 
947 void pcie_cap_arifwd_reset(PCIDevice *dev)
948 {
949     uint8_t *devctl2 = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL2;
950     pci_long_test_and_clear_mask(devctl2, PCI_EXP_DEVCTL2_ARI);
951 }
952 
953 bool pcie_cap_is_arifwd_enabled(const PCIDevice *dev)
954 {
955     if (!pci_is_express(dev)) {
956         return false;
957     }
958     if (!dev->exp.exp_cap) {
959         return false;
960     }
961 
962     return pci_get_long(dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL2) &
963         PCI_EXP_DEVCTL2_ARI;
964 }
965 
966 /**************************************************************************
967  * pci express extended capability list management functions
968  * uint16_t ext_cap_id (16 bit)
969  * uint8_t cap_ver (4 bit)
970  * uint16_t cap_offset (12 bit)
971  * uint16_t ext_cap_size
972  */
973 
974 /* Passing a cap_id value > 0xffff will return 0 and put end of list in prev */
975 static uint16_t pcie_find_capability_list(PCIDevice *dev, uint32_t cap_id,
976                                           uint16_t *prev_p)
977 {
978     uint16_t prev = 0;
979     uint16_t next;
980     uint32_t header = pci_get_long(dev->config + PCI_CONFIG_SPACE_SIZE);
981 
982     if (!header) {
983         /* no extended capability */
984         next = 0;
985         goto out;
986     }
987     for (next = PCI_CONFIG_SPACE_SIZE; next;
988          prev = next, next = PCI_EXT_CAP_NEXT(header)) {
989 
990         assert(next >= PCI_CONFIG_SPACE_SIZE);
991         assert(next <= PCIE_CONFIG_SPACE_SIZE - 8);
992 
993         header = pci_get_long(dev->config + next);
994         if (PCI_EXT_CAP_ID(header) == cap_id) {
995             break;
996         }
997     }
998 
999 out:
1000     if (prev_p) {
1001         *prev_p = prev;
1002     }
1003     return next;
1004 }
1005 
1006 uint16_t pcie_find_capability(PCIDevice *dev, uint16_t cap_id)
1007 {
1008     return pcie_find_capability_list(dev, cap_id, NULL);
1009 }
1010 
1011 static void pcie_ext_cap_set_next(PCIDevice *dev, uint16_t pos, uint16_t next)
1012 {
1013     uint32_t header = pci_get_long(dev->config + pos);
1014     assert(!(next & (PCI_EXT_CAP_ALIGN - 1)));
1015     header = (header & ~PCI_EXT_CAP_NEXT_MASK) |
1016         ((next << PCI_EXT_CAP_NEXT_SHIFT) & PCI_EXT_CAP_NEXT_MASK);
1017     pci_set_long(dev->config + pos, header);
1018 }
1019 
1020 /*
1021  * Caller must supply valid (offset, size) such that the range wouldn't
1022  * overlap with other capability or other registers.
1023  * This function doesn't check it.
1024  */
1025 void pcie_add_capability(PCIDevice *dev,
1026                          uint16_t cap_id, uint8_t cap_ver,
1027                          uint16_t offset, uint16_t size)
1028 {
1029     assert(offset >= PCI_CONFIG_SPACE_SIZE);
1030     assert(offset < (uint16_t)(offset + size));
1031     assert((uint16_t)(offset + size) <= PCIE_CONFIG_SPACE_SIZE);
1032     assert(size >= 8);
1033     assert(pci_is_express(dev));
1034 
1035     if (offset != PCI_CONFIG_SPACE_SIZE) {
1036         uint16_t prev;
1037 
1038         /*
1039          * 0xffffffff is not a valid cap id (it's a 16 bit field). use
1040          * internally to find the last capability in the linked list.
1041          */
1042         pcie_find_capability_list(dev, 0xffffffff, &prev);
1043         assert(prev >= PCI_CONFIG_SPACE_SIZE);
1044         pcie_ext_cap_set_next(dev, prev, offset);
1045     }
1046     pci_set_long(dev->config + offset, PCI_EXT_CAP(cap_id, cap_ver, 0));
1047 
1048     /* Make capability read-only by default */
1049     memset(dev->wmask + offset, 0, size);
1050     memset(dev->w1cmask + offset, 0, size);
1051     /* Check capability by default */
1052     memset(dev->cmask + offset, 0xFF, size);
1053 }
1054 
1055 /*
1056  * Sync the PCIe Link Status negotiated speed and width of a bridge with the
1057  * downstream device.  If downstream device is not present, re-write with the
1058  * Link Capability fields.  If downstream device reports invalid width or
1059  * speed, replace with minimum values (LnkSta fields are RsvdZ on VFs but such
1060  * values interfere with PCIe native hotplug detecting new devices).  Limit
1061  * width and speed to bridge capabilities for compatibility.  Use config_read
1062  * to access the downstream device since it could be an assigned device with
1063  * volatile link information.
1064  */
1065 void pcie_sync_bridge_lnk(PCIDevice *bridge_dev)
1066 {
1067     PCIBridge *br = PCI_BRIDGE(bridge_dev);
1068     PCIBus *bus = pci_bridge_get_sec_bus(br);
1069     PCIDevice *target = bus->devices[0];
1070     uint8_t *exp_cap = bridge_dev->config + bridge_dev->exp.exp_cap;
1071     uint16_t lnksta, lnkcap = pci_get_word(exp_cap + PCI_EXP_LNKCAP);
1072 
1073     if (!target || !target->exp.exp_cap) {
1074         lnksta = lnkcap;
1075     } else {
1076         lnksta = target->config_read(target,
1077                                      target->exp.exp_cap + PCI_EXP_LNKSTA,
1078                                      sizeof(lnksta));
1079 
1080         if ((lnksta & PCI_EXP_LNKSTA_NLW) > (lnkcap & PCI_EXP_LNKCAP_MLW)) {
1081             lnksta &= ~PCI_EXP_LNKSTA_NLW;
1082             lnksta |= lnkcap & PCI_EXP_LNKCAP_MLW;
1083         } else if (!(lnksta & PCI_EXP_LNKSTA_NLW)) {
1084             lnksta |= QEMU_PCI_EXP_LNKSTA_NLW(QEMU_PCI_EXP_LNK_X1);
1085         }
1086 
1087         if ((lnksta & PCI_EXP_LNKSTA_CLS) > (lnkcap & PCI_EXP_LNKCAP_SLS)) {
1088             lnksta &= ~PCI_EXP_LNKSTA_CLS;
1089             lnksta |= lnkcap & PCI_EXP_LNKCAP_SLS;
1090         } else if (!(lnksta & PCI_EXP_LNKSTA_CLS)) {
1091             lnksta |= QEMU_PCI_EXP_LNKSTA_CLS(QEMU_PCI_EXP_LNK_2_5GT);
1092         }
1093     }
1094 
1095     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKSTA,
1096                                  PCI_EXP_LNKSTA_CLS | PCI_EXP_LNKSTA_NLW);
1097     pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA, lnksta &
1098                                (PCI_EXP_LNKSTA_CLS | PCI_EXP_LNKSTA_NLW));
1099 }
1100 
1101 /**************************************************************************
1102  * pci express extended capability helper functions
1103  */
1104 
1105 /* ARI */
1106 void pcie_ari_init(PCIDevice *dev, uint16_t offset)
1107 {
1108     uint16_t nextfn = dev->cap_present & QEMU_PCIE_ARI_NEXTFN_1 ? 1 : 0;
1109 
1110     pcie_add_capability(dev, PCI_EXT_CAP_ID_ARI, PCI_ARI_VER,
1111                         offset, PCI_ARI_SIZEOF);
1112     pci_set_long(dev->config + offset + PCI_ARI_CAP, (nextfn & 0xff) << 8);
1113 }
1114 
1115 void pcie_dev_ser_num_init(PCIDevice *dev, uint16_t offset, uint64_t ser_num)
1116 {
1117     static const int pci_dsn_ver = 1;
1118     static const int pci_dsn_cap = 4;
1119 
1120     pcie_add_capability(dev, PCI_EXT_CAP_ID_DSN, pci_dsn_ver, offset,
1121                         PCI_EXT_CAP_DSN_SIZEOF);
1122     pci_set_quad(dev->config + offset + pci_dsn_cap, ser_num);
1123 }
1124 
1125 void pcie_ats_init(PCIDevice *dev, uint16_t offset, bool aligned)
1126 {
1127     pcie_add_capability(dev, PCI_EXT_CAP_ID_ATS, 0x1,
1128                         offset, PCI_EXT_CAP_ATS_SIZEOF);
1129 
1130     dev->exp.ats_cap = offset;
1131 
1132     /* Invalidate Queue Depth 0 */
1133     if (aligned) {
1134         pci_set_word(dev->config + offset + PCI_ATS_CAP,
1135                      PCI_ATS_CAP_PAGE_ALIGNED);
1136     }
1137     /* STU 0, Disabled by default */
1138     pci_set_word(dev->config + offset + PCI_ATS_CTRL, 0);
1139 
1140     pci_set_word(dev->wmask + dev->exp.ats_cap + PCI_ATS_CTRL, 0x800f);
1141 }
1142 
1143 /* ACS (Access Control Services) */
1144 void pcie_acs_init(PCIDevice *dev, uint16_t offset)
1145 {
1146     bool is_downstream = pci_is_express_downstream_port(dev);
1147     uint16_t cap_bits = 0;
1148 
1149     /* For endpoints, only multifunction devs may have an ACS capability: */
1150     assert(is_downstream ||
1151            (dev->cap_present & QEMU_PCI_CAP_MULTIFUNCTION) ||
1152            PCI_FUNC(dev->devfn));
1153 
1154     pcie_add_capability(dev, PCI_EXT_CAP_ID_ACS, PCI_ACS_VER, offset,
1155                         PCI_ACS_SIZEOF);
1156     dev->exp.acs_cap = offset;
1157 
1158     if (is_downstream) {
1159         /*
1160          * Downstream ports must implement SV, TB, RR, CR, UF, and DT (with
1161          * caveats on the latter four that we ignore for simplicity).
1162          * Endpoints may also implement a subset of ACS capabilities,
1163          * but these are optional if the endpoint does not support
1164          * peer-to-peer between functions and thus omitted here.
1165          */
1166         cap_bits = PCI_ACS_SV | PCI_ACS_TB | PCI_ACS_RR |
1167             PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_DT;
1168     }
1169 
1170     pci_set_word(dev->config + offset + PCI_ACS_CAP, cap_bits);
1171     pci_set_word(dev->wmask + offset + PCI_ACS_CTRL, cap_bits);
1172 }
1173 
1174 void pcie_acs_reset(PCIDevice *dev)
1175 {
1176     if (dev->exp.acs_cap) {
1177         pci_set_word(dev->config + dev->exp.acs_cap + PCI_ACS_CTRL, 0);
1178     }
1179 }
1180