xref: /openbmc/qemu/hw/pci/pcie.c (revision ed5abf46)
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 
32 //#define DEBUG_PCIE
33 #ifdef DEBUG_PCIE
34 # define PCIE_DPRINTF(fmt, ...)                                         \
35     fprintf(stderr, "%s:%d " fmt, __func__, __LINE__, ## __VA_ARGS__)
36 #else
37 # define PCIE_DPRINTF(fmt, ...) do {} while (0)
38 #endif
39 #define PCIE_DEV_PRINTF(dev, fmt, ...)                                  \
40     PCIE_DPRINTF("%s:%x "fmt, (dev)->name, (dev)->devfn, ## __VA_ARGS__)
41 
42 
43 /***************************************************************************
44  * pci express capability helper functions
45  */
46 
47 static void
48 pcie_cap_v1_fill(PCIDevice *dev, uint8_t port, uint8_t type, uint8_t version)
49 {
50     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
51     uint8_t *cmask = dev->cmask + dev->exp.exp_cap;
52 
53     /* capability register
54     interrupt message number defaults to 0 */
55     pci_set_word(exp_cap + PCI_EXP_FLAGS,
56                  ((type << PCI_EXP_FLAGS_TYPE_SHIFT) & PCI_EXP_FLAGS_TYPE) |
57                  version);
58 
59     /* device capability register
60      * table 7-12:
61      * roll based error reporting bit must be set by all
62      * Functions conforming to the ECN, PCI Express Base
63      * Specification, Revision 1.1., or subsequent PCI Express Base
64      * Specification revisions.
65      */
66     pci_set_long(exp_cap + PCI_EXP_DEVCAP, PCI_EXP_DEVCAP_RBER);
67 
68     pci_set_long(exp_cap + PCI_EXP_LNKCAP,
69                  (port << PCI_EXP_LNKCAP_PN_SHIFT) |
70                  PCI_EXP_LNKCAP_ASPMS_0S |
71                  QEMU_PCI_EXP_LNKCAP_MLW(QEMU_PCI_EXP_LNK_X1) |
72                  QEMU_PCI_EXP_LNKCAP_MLS(QEMU_PCI_EXP_LNK_2_5GT));
73 
74     pci_set_word(exp_cap + PCI_EXP_LNKSTA,
75                  QEMU_PCI_EXP_LNKSTA_NLW(QEMU_PCI_EXP_LNK_X1) |
76                  QEMU_PCI_EXP_LNKSTA_CLS(QEMU_PCI_EXP_LNK_2_5GT));
77 
78     if (dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) {
79         pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA,
80                                    PCI_EXP_LNKSTA_DLLLA);
81     }
82 
83     /* We changed link status bits over time, and changing them across
84      * migrations is generally fine as hardware changes them too.
85      * Let's not bother checking.
86      */
87     pci_set_word(cmask + PCI_EXP_LNKSTA, 0);
88 }
89 
90 static void pcie_cap_fill_slot_lnk(PCIDevice *dev)
91 {
92     PCIESlot *s = (PCIESlot *)object_dynamic_cast(OBJECT(dev), TYPE_PCIE_SLOT);
93     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
94 
95     /* Skip anything that isn't a PCIESlot */
96     if (!s) {
97         return;
98     }
99 
100     /* Clear and fill LNKCAP from what was configured above */
101     pci_long_test_and_clear_mask(exp_cap + PCI_EXP_LNKCAP,
102                                  PCI_EXP_LNKCAP_MLW | PCI_EXP_LNKCAP_SLS);
103     pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP,
104                                QEMU_PCI_EXP_LNKCAP_MLW(s->width) |
105                                QEMU_PCI_EXP_LNKCAP_MLS(s->speed));
106 
107     /*
108      * Link bandwidth notification is required for all root ports and
109      * downstream ports supporting links wider than x1 or multiple link
110      * speeds.
111      */
112     if (s->width > QEMU_PCI_EXP_LNK_X1 ||
113         s->speed > QEMU_PCI_EXP_LNK_2_5GT) {
114         pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP,
115                                    PCI_EXP_LNKCAP_LBNC);
116     }
117 
118     if (s->speed > QEMU_PCI_EXP_LNK_2_5GT) {
119         /*
120          * Hot-plug capable downstream ports and downstream ports supporting
121          * link speeds greater than 5GT/s must hardwire PCI_EXP_LNKCAP_DLLLARC
122          * to 1b.  PCI_EXP_LNKCAP_DLLLARC implies PCI_EXP_LNKSTA_DLLLA, which
123          * we also hardwire to 1b here.  2.5GT/s hot-plug slots should also
124          * technically implement this, but it's not done here for compatibility.
125          */
126         pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP,
127                                    PCI_EXP_LNKCAP_DLLLARC);
128         pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA,
129                                    PCI_EXP_LNKSTA_DLLLA);
130 
131         /*
132          * Target Link Speed defaults to the highest link speed supported by
133          * the component.  2.5GT/s devices are permitted to hardwire to zero.
134          */
135         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKCTL2,
136                                      PCI_EXP_LNKCTL2_TLS);
137         pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKCTL2,
138                                    QEMU_PCI_EXP_LNKCAP_MLS(s->speed) &
139                                    PCI_EXP_LNKCTL2_TLS);
140     }
141 
142     /*
143      * 2.5 & 5.0GT/s can be fully described by LNKCAP, but 8.0GT/s is
144      * actually a reference to the highest bit supported in this register.
145      * We assume the device supports all link speeds.
146      */
147     if (s->speed > QEMU_PCI_EXP_LNK_5GT) {
148         pci_long_test_and_clear_mask(exp_cap + PCI_EXP_LNKCAP2, ~0U);
149         pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP2,
150                                    PCI_EXP_LNKCAP2_SLS_2_5GB |
151                                    PCI_EXP_LNKCAP2_SLS_5_0GB |
152                                    PCI_EXP_LNKCAP2_SLS_8_0GB);
153         if (s->speed > QEMU_PCI_EXP_LNK_8GT) {
154             pci_long_test_and_set_mask(exp_cap + PCI_EXP_LNKCAP2,
155                                        PCI_EXP_LNKCAP2_SLS_16_0GB);
156         }
157     }
158 }
159 
160 int pcie_cap_init(PCIDevice *dev, uint8_t offset,
161                   uint8_t type, uint8_t port,
162                   Error **errp)
163 {
164     /* PCIe cap v2 init */
165     int pos;
166     uint8_t *exp_cap;
167 
168     assert(pci_is_express(dev));
169 
170     pos = pci_add_capability(dev, PCI_CAP_ID_EXP, offset,
171                              PCI_EXP_VER2_SIZEOF, errp);
172     if (pos < 0) {
173         return pos;
174     }
175     dev->exp.exp_cap = pos;
176     exp_cap = dev->config + pos;
177 
178     /* Filling values common with v1 */
179     pcie_cap_v1_fill(dev, port, type, PCI_EXP_FLAGS_VER2);
180 
181     /* Fill link speed and width options */
182     pcie_cap_fill_slot_lnk(dev);
183 
184     /* Filling v2 specific values */
185     pci_set_long(exp_cap + PCI_EXP_DEVCAP2,
186                  PCI_EXP_DEVCAP2_EFF | PCI_EXP_DEVCAP2_EETLPP);
187 
188     pci_set_word(dev->wmask + pos + PCI_EXP_DEVCTL2, PCI_EXP_DEVCTL2_EETLPPB);
189 
190     if (dev->cap_present & QEMU_PCIE_EXTCAP_INIT) {
191         /* read-only to behave like a 'NULL' Extended Capability Header */
192         pci_set_long(dev->wmask + PCI_CONFIG_SPACE_SIZE, 0);
193     }
194 
195     return pos;
196 }
197 
198 int pcie_cap_v1_init(PCIDevice *dev, uint8_t offset, uint8_t type,
199                      uint8_t port)
200 {
201     /* PCIe cap v1 init */
202     int pos;
203     Error *local_err = NULL;
204 
205     assert(pci_is_express(dev));
206 
207     pos = pci_add_capability(dev, PCI_CAP_ID_EXP, offset,
208                              PCI_EXP_VER1_SIZEOF, &local_err);
209     if (pos < 0) {
210         error_report_err(local_err);
211         return pos;
212     }
213     dev->exp.exp_cap = pos;
214 
215     pcie_cap_v1_fill(dev, port, type, PCI_EXP_FLAGS_VER1);
216 
217     return pos;
218 }
219 
220 static int
221 pcie_endpoint_cap_common_init(PCIDevice *dev, uint8_t offset, uint8_t cap_size)
222 {
223     uint8_t type = PCI_EXP_TYPE_ENDPOINT;
224     Error *local_err = NULL;
225     int ret;
226 
227     /*
228      * Windows guests will report Code 10, device cannot start, if
229      * a regular Endpoint type is exposed on a root complex.  These
230      * should instead be Root Complex Integrated Endpoints.
231      */
232     if (pci_bus_is_express(pci_get_bus(dev))
233         && pci_bus_is_root(pci_get_bus(dev))) {
234         type = PCI_EXP_TYPE_RC_END;
235     }
236 
237     if (cap_size == PCI_EXP_VER1_SIZEOF) {
238         return pcie_cap_v1_init(dev, offset, type, 0);
239     } else {
240         ret = pcie_cap_init(dev, offset, type, 0, &local_err);
241 
242         if (ret < 0) {
243             error_report_err(local_err);
244         }
245 
246         return ret;
247     }
248 }
249 
250 int pcie_endpoint_cap_init(PCIDevice *dev, uint8_t offset)
251 {
252     return pcie_endpoint_cap_common_init(dev, offset, PCI_EXP_VER2_SIZEOF);
253 }
254 
255 int pcie_endpoint_cap_v1_init(PCIDevice *dev, uint8_t offset)
256 {
257     return pcie_endpoint_cap_common_init(dev, offset, PCI_EXP_VER1_SIZEOF);
258 }
259 
260 void pcie_cap_exit(PCIDevice *dev)
261 {
262     pci_del_capability(dev, PCI_CAP_ID_EXP, PCI_EXP_VER2_SIZEOF);
263 }
264 
265 void pcie_cap_v1_exit(PCIDevice *dev)
266 {
267     pci_del_capability(dev, PCI_CAP_ID_EXP, PCI_EXP_VER1_SIZEOF);
268 }
269 
270 uint8_t pcie_cap_get_type(const PCIDevice *dev)
271 {
272     uint32_t pos = dev->exp.exp_cap;
273     assert(pos > 0);
274     return (pci_get_word(dev->config + pos + PCI_EXP_FLAGS) &
275             PCI_EXP_FLAGS_TYPE) >> PCI_EXP_FLAGS_TYPE_SHIFT;
276 }
277 
278 /* MSI/MSI-X */
279 /* pci express interrupt message number */
280 /* 7.8.2 PCI Express Capabilities Register: Interrupt Message Number */
281 void pcie_cap_flags_set_vector(PCIDevice *dev, uint8_t vector)
282 {
283     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
284     assert(vector < 32);
285     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_FLAGS, PCI_EXP_FLAGS_IRQ);
286     pci_word_test_and_set_mask(exp_cap + PCI_EXP_FLAGS,
287                                vector << PCI_EXP_FLAGS_IRQ_SHIFT);
288 }
289 
290 uint8_t pcie_cap_flags_get_vector(PCIDevice *dev)
291 {
292     return (pci_get_word(dev->config + dev->exp.exp_cap + PCI_EXP_FLAGS) &
293             PCI_EXP_FLAGS_IRQ) >> PCI_EXP_FLAGS_IRQ_SHIFT;
294 }
295 
296 void pcie_cap_deverr_init(PCIDevice *dev)
297 {
298     uint32_t pos = dev->exp.exp_cap;
299     pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_DEVCAP,
300                                PCI_EXP_DEVCAP_RBER);
301     pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_DEVCTL,
302                                PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE |
303                                PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE);
304     pci_long_test_and_set_mask(dev->w1cmask + pos + PCI_EXP_DEVSTA,
305                                PCI_EXP_DEVSTA_CED | PCI_EXP_DEVSTA_NFED |
306                                PCI_EXP_DEVSTA_FED | PCI_EXP_DEVSTA_URD);
307 }
308 
309 void pcie_cap_deverr_reset(PCIDevice *dev)
310 {
311     uint8_t *devctl = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL;
312     pci_long_test_and_clear_mask(devctl,
313                                  PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE |
314                                  PCI_EXP_DEVCTL_FERE | PCI_EXP_DEVCTL_URRE);
315 }
316 
317 void pcie_cap_lnkctl_init(PCIDevice *dev)
318 {
319     uint32_t pos = dev->exp.exp_cap;
320     pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_LNKCTL,
321                                PCI_EXP_LNKCTL_CCC | PCI_EXP_LNKCTL_ES);
322 }
323 
324 void pcie_cap_lnkctl_reset(PCIDevice *dev)
325 {
326     uint8_t *lnkctl = dev->config + dev->exp.exp_cap + PCI_EXP_LNKCTL;
327     pci_long_test_and_clear_mask(lnkctl,
328                                  PCI_EXP_LNKCTL_CCC | PCI_EXP_LNKCTL_ES);
329 }
330 
331 static void hotplug_event_update_event_status(PCIDevice *dev)
332 {
333     uint32_t pos = dev->exp.exp_cap;
334     uint8_t *exp_cap = dev->config + pos;
335     uint16_t sltctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
336     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
337 
338     dev->exp.hpev_notified = (sltctl & PCI_EXP_SLTCTL_HPIE) &&
339         (sltsta & sltctl & PCI_EXP_HP_EV_SUPPORTED);
340 }
341 
342 static void hotplug_event_notify(PCIDevice *dev)
343 {
344     bool prev = dev->exp.hpev_notified;
345 
346     hotplug_event_update_event_status(dev);
347 
348     if (prev == dev->exp.hpev_notified) {
349         return;
350     }
351 
352     /* Note: the logic above does not take into account whether interrupts
353      * are masked. The result is that interrupt will be sent when it is
354      * subsequently unmasked. This appears to be legal: Section 6.7.3.4:
355      * The Port may optionally send an MSI when there are hot-plug events that
356      * occur while interrupt generation is disabled, and interrupt generation is
357      * subsequently enabled. */
358     if (msix_enabled(dev)) {
359         msix_notify(dev, pcie_cap_flags_get_vector(dev));
360     } else if (msi_enabled(dev)) {
361         msi_notify(dev, pcie_cap_flags_get_vector(dev));
362     } else {
363         pci_set_irq(dev, dev->exp.hpev_notified);
364     }
365 }
366 
367 static void hotplug_event_clear(PCIDevice *dev)
368 {
369     hotplug_event_update_event_status(dev);
370     if (!msix_enabled(dev) && !msi_enabled(dev) && !dev->exp.hpev_notified) {
371         pci_irq_deassert(dev);
372     }
373 }
374 
375 /*
376  * A PCI Express Hot-Plug Event has occurred, so update slot status register
377  * and notify OS of the event if necessary.
378  *
379  * 6.7.3 PCI Express Hot-Plug Events
380  * 6.7.3.4 Software Notification of Hot-Plug Events
381  */
382 static void pcie_cap_slot_event(PCIDevice *dev, PCIExpressHotPlugEvent event)
383 {
384     /* Minor optimization: if nothing changed - no event is needed. */
385     if (pci_word_test_and_set_mask(dev->config + dev->exp.exp_cap +
386                                    PCI_EXP_SLTSTA, event) == event) {
387         return;
388     }
389     hotplug_event_notify(dev);
390 }
391 
392 static void pcie_cap_slot_plug_common(PCIDevice *hotplug_dev, DeviceState *dev,
393                                       Error **errp)
394 {
395     uint8_t *exp_cap = hotplug_dev->config + hotplug_dev->exp.exp_cap;
396     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
397 
398     PCIE_DEV_PRINTF(PCI_DEVICE(dev), "hotplug state: 0x%x\n", sltsta);
399     if (sltsta & PCI_EXP_SLTSTA_EIS) {
400         /* the slot is electromechanically locked.
401          * This error is propagated up to qdev and then to HMP/QMP.
402          */
403         error_setg_errno(errp, EBUSY, "slot is electromechanically locked");
404     }
405 }
406 
407 void pcie_cap_slot_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
408                                Error **errp)
409 {
410     pcie_cap_slot_plug_common(PCI_DEVICE(hotplug_dev), dev, errp);
411 }
412 
413 void pcie_cap_slot_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
414                            Error **errp)
415 {
416     PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev);
417     uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap;
418     PCIDevice *pci_dev = PCI_DEVICE(dev);
419 
420     /* Don't send event when device is enabled during qemu machine creation:
421      * it is present on boot, no hotplug event is necessary. We do send an
422      * event when the device is disabled later. */
423     if (!dev->hotplugged) {
424         pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,
425                                    PCI_EXP_SLTSTA_PDS);
426         if (pci_dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) {
427             pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA,
428                                        PCI_EXP_LNKSTA_DLLLA);
429         }
430         return;
431     }
432 
433     /* To enable multifunction hot-plug, we just ensure the function
434      * 0 added last. When function 0 is added, we set the sltsta and
435      * inform OS via event notification.
436      */
437     if (pci_get_function_0(pci_dev)) {
438         pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,
439                                    PCI_EXP_SLTSTA_PDS);
440         if (pci_dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) {
441             pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA,
442                                        PCI_EXP_LNKSTA_DLLLA);
443         }
444         pcie_cap_slot_event(PCI_DEVICE(hotplug_dev),
445                             PCI_EXP_HP_EV_PDC | PCI_EXP_HP_EV_ABP);
446     }
447 }
448 
449 void pcie_cap_slot_unplug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
450                              Error **errp)
451 {
452     object_property_set_bool(OBJECT(dev), false, "realized", NULL);
453 }
454 
455 static void pcie_unplug_device(PCIBus *bus, PCIDevice *dev, void *opaque)
456 {
457     HotplugHandler *hotplug_ctrl = qdev_get_hotplug_handler(DEVICE(dev));
458 
459     if (dev->partially_hotplugged) {
460         dev->qdev.pending_deleted_event = false;
461         return;
462     }
463     hotplug_handler_unplug(hotplug_ctrl, DEVICE(dev), &error_abort);
464     object_unparent(OBJECT(dev));
465 }
466 
467 void pcie_cap_slot_unplug_request_cb(HotplugHandler *hotplug_dev,
468                                      DeviceState *dev, Error **errp)
469 {
470     Error *local_err = NULL;
471     PCIDevice *pci_dev = PCI_DEVICE(dev);
472     PCIBus *bus = pci_get_bus(pci_dev);
473 
474     pcie_cap_slot_plug_common(PCI_DEVICE(hotplug_dev), dev, &local_err);
475     if (local_err) {
476         error_propagate(errp, local_err);
477         return;
478     }
479 
480     dev->pending_deleted_event = true;
481 
482     /* In case user cancel the operation of multi-function hot-add,
483      * remove the function that is unexposed to guest individually,
484      * without interaction with guest.
485      */
486     if (pci_dev->devfn &&
487         !bus->devices[0]) {
488         pcie_unplug_device(bus, pci_dev, NULL);
489 
490         return;
491     }
492 
493     pcie_cap_slot_push_attention_button(PCI_DEVICE(hotplug_dev));
494 }
495 
496 /* pci express slot for pci express root/downstream port
497    PCI express capability slot registers */
498 void pcie_cap_slot_init(PCIDevice *dev, PCIESlot *s)
499 {
500     uint32_t pos = dev->exp.exp_cap;
501 
502     pci_word_test_and_set_mask(dev->config + pos + PCI_EXP_FLAGS,
503                                PCI_EXP_FLAGS_SLOT);
504 
505     pci_long_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCAP,
506                                  ~PCI_EXP_SLTCAP_PSN);
507     pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
508                                (s->slot << PCI_EXP_SLTCAP_PSN_SHIFT) |
509                                PCI_EXP_SLTCAP_EIP |
510                                PCI_EXP_SLTCAP_PIP |
511                                PCI_EXP_SLTCAP_AIP |
512                                PCI_EXP_SLTCAP_ABP);
513     if (s->hotplug) {
514         pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
515                                    PCI_EXP_SLTCAP_HPS |
516                                    PCI_EXP_SLTCAP_HPC);
517     }
518 
519     if (dev->cap_present & QEMU_PCIE_SLTCAP_PCP) {
520         pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCAP,
521                                    PCI_EXP_SLTCAP_PCP);
522         pci_word_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCTL,
523                                      PCI_EXP_SLTCTL_PCC);
524         pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,
525                                    PCI_EXP_SLTCTL_PCC);
526     }
527 
528     pci_word_test_and_clear_mask(dev->config + pos + PCI_EXP_SLTCTL,
529                                  PCI_EXP_SLTCTL_PIC |
530                                  PCI_EXP_SLTCTL_AIC);
531     pci_word_test_and_set_mask(dev->config + pos + PCI_EXP_SLTCTL,
532                                PCI_EXP_SLTCTL_PIC_OFF |
533                                PCI_EXP_SLTCTL_AIC_OFF);
534     pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,
535                                PCI_EXP_SLTCTL_PIC |
536                                PCI_EXP_SLTCTL_AIC |
537                                PCI_EXP_SLTCTL_HPIE |
538                                PCI_EXP_SLTCTL_CCIE |
539                                PCI_EXP_SLTCTL_PDCE |
540                                PCI_EXP_SLTCTL_ABPE);
541     /* Although reading PCI_EXP_SLTCTL_EIC returns always 0,
542      * make the bit writable here in order to detect 1b is written.
543      * pcie_cap_slot_write_config() test-and-clear the bit, so
544      * this bit always returns 0 to the guest.
545      */
546     pci_word_test_and_set_mask(dev->wmask + pos + PCI_EXP_SLTCTL,
547                                PCI_EXP_SLTCTL_EIC);
548 
549     pci_word_test_and_set_mask(dev->w1cmask + pos + PCI_EXP_SLTSTA,
550                                PCI_EXP_HP_EV_SUPPORTED);
551 
552     dev->exp.hpev_notified = false;
553 
554     qbus_set_hotplug_handler(BUS(pci_bridge_get_sec_bus(PCI_BRIDGE(dev))),
555                              OBJECT(dev), NULL);
556 }
557 
558 void pcie_cap_slot_reset(PCIDevice *dev)
559 {
560     uint8_t *exp_cap = dev->config + dev->exp.exp_cap;
561     uint8_t port_type = pcie_cap_get_type(dev);
562 
563     assert(port_type == PCI_EXP_TYPE_DOWNSTREAM ||
564            port_type == PCI_EXP_TYPE_ROOT_PORT);
565 
566     PCIE_DEV_PRINTF(dev, "reset\n");
567 
568     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,
569                                  PCI_EXP_SLTCTL_EIC |
570                                  PCI_EXP_SLTCTL_PIC |
571                                  PCI_EXP_SLTCTL_AIC |
572                                  PCI_EXP_SLTCTL_HPIE |
573                                  PCI_EXP_SLTCTL_CCIE |
574                                  PCI_EXP_SLTCTL_PDCE |
575                                  PCI_EXP_SLTCTL_ABPE);
576     pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTCTL,
577                                PCI_EXP_SLTCTL_AIC_OFF);
578 
579     if (dev->cap_present & QEMU_PCIE_SLTCAP_PCP) {
580         /* Downstream ports enforce device number 0. */
581         bool populated = pci_bridge_get_sec_bus(PCI_BRIDGE(dev))->devices[0];
582         uint16_t pic;
583 
584         if (populated) {
585             pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,
586                                          PCI_EXP_SLTCTL_PCC);
587         } else {
588             pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTCTL,
589                                        PCI_EXP_SLTCTL_PCC);
590         }
591 
592         pic = populated ? PCI_EXP_SLTCTL_PIC_ON : PCI_EXP_SLTCTL_PIC_OFF;
593         pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTCTL, pic);
594     }
595 
596     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
597                                  PCI_EXP_SLTSTA_EIS |/* on reset,
598                                                         the lock is released */
599                                  PCI_EXP_SLTSTA_CC |
600                                  PCI_EXP_SLTSTA_PDC |
601                                  PCI_EXP_SLTSTA_ABP);
602 
603     hotplug_event_update_event_status(dev);
604 }
605 
606 void pcie_cap_slot_get(PCIDevice *dev, uint16_t *slt_ctl, uint16_t *slt_sta)
607 {
608     uint32_t pos = dev->exp.exp_cap;
609     uint8_t *exp_cap = dev->config + pos;
610     *slt_ctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
611     *slt_sta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
612 }
613 
614 void pcie_cap_slot_write_config(PCIDevice *dev,
615                                 uint16_t old_slt_ctl, uint16_t old_slt_sta,
616                                 uint32_t addr, uint32_t val, int len)
617 {
618     uint32_t pos = dev->exp.exp_cap;
619     uint8_t *exp_cap = dev->config + pos;
620     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
621 
622     if (ranges_overlap(addr, len, pos + PCI_EXP_SLTSTA, 2)) {
623         /*
624          * Guests tend to clears all bits during init.
625          * If they clear bits that weren't set this is racy and will lose events:
626          * not a big problem for manual button presses, but a problem for us.
627          * As a work-around, detect this and revert status to what it was
628          * before the write.
629          *
630          * Note: in theory this can be detected as a duplicate button press
631          * which cancels the previous press. Does not seem to happen in
632          * practice as guests seem to only have this bug during init.
633          */
634 #define PCIE_SLOT_EVENTS (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD | \
635                           PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC | \
636                           PCI_EXP_SLTSTA_CC)
637 
638         if (val & ~old_slt_sta & PCIE_SLOT_EVENTS) {
639             sltsta = (sltsta & ~PCIE_SLOT_EVENTS) | (old_slt_sta & PCIE_SLOT_EVENTS);
640             pci_set_word(exp_cap + PCI_EXP_SLTSTA, sltsta);
641         }
642         hotplug_event_clear(dev);
643     }
644 
645     if (!ranges_overlap(addr, len, pos + PCI_EXP_SLTCTL, 2)) {
646         return;
647     }
648 
649     if (pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTCTL,
650                                      PCI_EXP_SLTCTL_EIC)) {
651         sltsta ^= PCI_EXP_SLTSTA_EIS; /* toggle PCI_EXP_SLTSTA_EIS bit */
652         pci_set_word(exp_cap + PCI_EXP_SLTSTA, sltsta);
653         PCIE_DEV_PRINTF(dev, "PCI_EXP_SLTCTL_EIC: "
654                         "sltsta -> 0x%02"PRIx16"\n",
655                         sltsta);
656     }
657 
658     /*
659      * If the slot is populated, power indicator is off and power
660      * controller is off, it is safe to detach the devices.
661      *
662      * Note: don't detach if condition was already true:
663      * this is a work around for guests that overwrite
664      * control of powered off slots before powering them on.
665      */
666     if ((sltsta & PCI_EXP_SLTSTA_PDS) && (val & PCI_EXP_SLTCTL_PCC) &&
667         (val & PCI_EXP_SLTCTL_PIC_OFF) == PCI_EXP_SLTCTL_PIC_OFF &&
668         (!(old_slt_ctl & PCI_EXP_SLTCTL_PCC) ||
669         (old_slt_ctl & PCI_EXP_SLTCTL_PIC_OFF) != PCI_EXP_SLTCTL_PIC_OFF)) {
670         PCIBus *sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(dev));
671         pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
672                             pcie_unplug_device, NULL);
673 
674         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
675                                      PCI_EXP_SLTSTA_PDS);
676         if (dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) {
677             pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKSTA,
678                                          PCI_EXP_LNKSTA_DLLLA);
679         }
680         pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA,
681                                        PCI_EXP_SLTSTA_PDC);
682     }
683 
684     hotplug_event_notify(dev);
685 
686     /*
687      * 6.7.3.2 Command Completed Events
688      *
689      * Software issues a command to a hot-plug capable Downstream Port by
690      * issuing a write transaction that targets any portion of the Port’s Slot
691      * Control register. A single write to the Slot Control register is
692      * considered to be a single command, even if the write affects more than
693      * one field in the Slot Control register. In response to this transaction,
694      * the Port must carry out the requested actions and then set the
695      * associated status field for the command completed event. */
696 
697     /* Real hardware might take a while to complete requested command because
698      * physical movement would be involved like locking the electromechanical
699      * lock.  However in our case, command is completed instantaneously above,
700      * so send a command completion event right now.
701      */
702     pcie_cap_slot_event(dev, PCI_EXP_HP_EV_CCI);
703 }
704 
705 int pcie_cap_slot_post_load(void *opaque, int version_id)
706 {
707     PCIDevice *dev = opaque;
708     hotplug_event_update_event_status(dev);
709     return 0;
710 }
711 
712 void pcie_cap_slot_push_attention_button(PCIDevice *dev)
713 {
714     pcie_cap_slot_event(dev, PCI_EXP_HP_EV_ABP);
715 }
716 
717 /* root control/capabilities/status. PME isn't emulated for now */
718 void pcie_cap_root_init(PCIDevice *dev)
719 {
720     pci_set_word(dev->wmask + dev->exp.exp_cap + PCI_EXP_RTCTL,
721                  PCI_EXP_RTCTL_SECEE | PCI_EXP_RTCTL_SENFEE |
722                  PCI_EXP_RTCTL_SEFEE);
723 }
724 
725 void pcie_cap_root_reset(PCIDevice *dev)
726 {
727     pci_set_word(dev->config + dev->exp.exp_cap + PCI_EXP_RTCTL, 0);
728 }
729 
730 /* function level reset(FLR) */
731 void pcie_cap_flr_init(PCIDevice *dev)
732 {
733     pci_long_test_and_set_mask(dev->config + dev->exp.exp_cap + PCI_EXP_DEVCAP,
734                                PCI_EXP_DEVCAP_FLR);
735 
736     /* Although reading BCR_FLR returns always 0,
737      * the bit is made writable here in order to detect the 1b is written
738      * pcie_cap_flr_write_config() test-and-clear the bit, so
739      * this bit always returns 0 to the guest.
740      */
741     pci_word_test_and_set_mask(dev->wmask + dev->exp.exp_cap + PCI_EXP_DEVCTL,
742                                PCI_EXP_DEVCTL_BCR_FLR);
743 }
744 
745 void pcie_cap_flr_write_config(PCIDevice *dev,
746                                uint32_t addr, uint32_t val, int len)
747 {
748     uint8_t *devctl = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL;
749     if (pci_get_word(devctl) & PCI_EXP_DEVCTL_BCR_FLR) {
750         /* Clear PCI_EXP_DEVCTL_BCR_FLR after invoking the reset handler
751            so the handler can detect FLR by looking at this bit. */
752         pci_device_reset(dev);
753         pci_word_test_and_clear_mask(devctl, PCI_EXP_DEVCTL_BCR_FLR);
754     }
755 }
756 
757 /* Alternative Routing-ID Interpretation (ARI)
758  * forwarding support for root and downstream ports
759  */
760 void pcie_cap_arifwd_init(PCIDevice *dev)
761 {
762     uint32_t pos = dev->exp.exp_cap;
763     pci_long_test_and_set_mask(dev->config + pos + PCI_EXP_DEVCAP2,
764                                PCI_EXP_DEVCAP2_ARI);
765     pci_long_test_and_set_mask(dev->wmask + pos + PCI_EXP_DEVCTL2,
766                                PCI_EXP_DEVCTL2_ARI);
767 }
768 
769 void pcie_cap_arifwd_reset(PCIDevice *dev)
770 {
771     uint8_t *devctl2 = dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL2;
772     pci_long_test_and_clear_mask(devctl2, PCI_EXP_DEVCTL2_ARI);
773 }
774 
775 bool pcie_cap_is_arifwd_enabled(const PCIDevice *dev)
776 {
777     if (!pci_is_express(dev)) {
778         return false;
779     }
780     if (!dev->exp.exp_cap) {
781         return false;
782     }
783 
784     return pci_get_long(dev->config + dev->exp.exp_cap + PCI_EXP_DEVCTL2) &
785         PCI_EXP_DEVCTL2_ARI;
786 }
787 
788 /**************************************************************************
789  * pci express extended capability list management functions
790  * uint16_t ext_cap_id (16 bit)
791  * uint8_t cap_ver (4 bit)
792  * uint16_t cap_offset (12 bit)
793  * uint16_t ext_cap_size
794  */
795 
796 /* Passing a cap_id value > 0xffff will return 0 and put end of list in prev */
797 static uint16_t pcie_find_capability_list(PCIDevice *dev, uint32_t cap_id,
798                                           uint16_t *prev_p)
799 {
800     uint16_t prev = 0;
801     uint16_t next;
802     uint32_t header = pci_get_long(dev->config + PCI_CONFIG_SPACE_SIZE);
803 
804     if (!header) {
805         /* no extended capability */
806         next = 0;
807         goto out;
808     }
809     for (next = PCI_CONFIG_SPACE_SIZE; next;
810          prev = next, next = PCI_EXT_CAP_NEXT(header)) {
811 
812         assert(next >= PCI_CONFIG_SPACE_SIZE);
813         assert(next <= PCIE_CONFIG_SPACE_SIZE - 8);
814 
815         header = pci_get_long(dev->config + next);
816         if (PCI_EXT_CAP_ID(header) == cap_id) {
817             break;
818         }
819     }
820 
821 out:
822     if (prev_p) {
823         *prev_p = prev;
824     }
825     return next;
826 }
827 
828 uint16_t pcie_find_capability(PCIDevice *dev, uint16_t cap_id)
829 {
830     return pcie_find_capability_list(dev, cap_id, NULL);
831 }
832 
833 static void pcie_ext_cap_set_next(PCIDevice *dev, uint16_t pos, uint16_t next)
834 {
835     uint32_t header = pci_get_long(dev->config + pos);
836     assert(!(next & (PCI_EXT_CAP_ALIGN - 1)));
837     header = (header & ~PCI_EXT_CAP_NEXT_MASK) |
838         ((next << PCI_EXT_CAP_NEXT_SHIFT) & PCI_EXT_CAP_NEXT_MASK);
839     pci_set_long(dev->config + pos, header);
840 }
841 
842 /*
843  * Caller must supply valid (offset, size) such that the range wouldn't
844  * overlap with other capability or other registers.
845  * This function doesn't check it.
846  */
847 void pcie_add_capability(PCIDevice *dev,
848                          uint16_t cap_id, uint8_t cap_ver,
849                          uint16_t offset, uint16_t size)
850 {
851     assert(offset >= PCI_CONFIG_SPACE_SIZE);
852     assert(offset < offset + size);
853     assert(offset + size <= PCIE_CONFIG_SPACE_SIZE);
854     assert(size >= 8);
855     assert(pci_is_express(dev));
856 
857     if (offset != PCI_CONFIG_SPACE_SIZE) {
858         uint16_t prev;
859 
860         /*
861          * 0xffffffff is not a valid cap id (it's a 16 bit field). use
862          * internally to find the last capability in the linked list.
863          */
864         pcie_find_capability_list(dev, 0xffffffff, &prev);
865         assert(prev >= PCI_CONFIG_SPACE_SIZE);
866         pcie_ext_cap_set_next(dev, prev, offset);
867     }
868     pci_set_long(dev->config + offset, PCI_EXT_CAP(cap_id, cap_ver, 0));
869 
870     /* Make capability read-only by default */
871     memset(dev->wmask + offset, 0, size);
872     memset(dev->w1cmask + offset, 0, size);
873     /* Check capability by default */
874     memset(dev->cmask + offset, 0xFF, size);
875 }
876 
877 /*
878  * Sync the PCIe Link Status negotiated speed and width of a bridge with the
879  * downstream device.  If downstream device is not present, re-write with the
880  * Link Capability fields.  If downstream device reports invalid width or
881  * speed, replace with minimum values (LnkSta fields are RsvdZ on VFs but such
882  * values interfere with PCIe native hotplug detecting new devices).  Limit
883  * width and speed to bridge capabilities for compatibility.  Use config_read
884  * to access the downstream device since it could be an assigned device with
885  * volatile link information.
886  */
887 void pcie_sync_bridge_lnk(PCIDevice *bridge_dev)
888 {
889     PCIBridge *br = PCI_BRIDGE(bridge_dev);
890     PCIBus *bus = pci_bridge_get_sec_bus(br);
891     PCIDevice *target = bus->devices[0];
892     uint8_t *exp_cap = bridge_dev->config + bridge_dev->exp.exp_cap;
893     uint16_t lnksta, lnkcap = pci_get_word(exp_cap + PCI_EXP_LNKCAP);
894 
895     if (!target || !target->exp.exp_cap) {
896         lnksta = lnkcap;
897     } else {
898         lnksta = target->config_read(target,
899                                      target->exp.exp_cap + PCI_EXP_LNKSTA,
900                                      sizeof(lnksta));
901 
902         if ((lnksta & PCI_EXP_LNKSTA_NLW) > (lnkcap & PCI_EXP_LNKCAP_MLW)) {
903             lnksta &= ~PCI_EXP_LNKSTA_NLW;
904             lnksta |= lnkcap & PCI_EXP_LNKCAP_MLW;
905         } else if (!(lnksta & PCI_EXP_LNKSTA_NLW)) {
906             lnksta |= QEMU_PCI_EXP_LNKSTA_NLW(QEMU_PCI_EXP_LNK_X1);
907         }
908 
909         if ((lnksta & PCI_EXP_LNKSTA_CLS) > (lnkcap & PCI_EXP_LNKCAP_SLS)) {
910             lnksta &= ~PCI_EXP_LNKSTA_CLS;
911             lnksta |= lnkcap & PCI_EXP_LNKCAP_SLS;
912         } else if (!(lnksta & PCI_EXP_LNKSTA_CLS)) {
913             lnksta |= QEMU_PCI_EXP_LNKSTA_CLS(QEMU_PCI_EXP_LNK_2_5GT);
914         }
915     }
916 
917     pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKSTA,
918                                  PCI_EXP_LNKSTA_CLS | PCI_EXP_LNKSTA_NLW);
919     pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA, lnksta &
920                                (PCI_EXP_LNKSTA_CLS | PCI_EXP_LNKSTA_NLW));
921 }
922 
923 /**************************************************************************
924  * pci express extended capability helper functions
925  */
926 
927 /* ARI */
928 void pcie_ari_init(PCIDevice *dev, uint16_t offset, uint16_t nextfn)
929 {
930     pcie_add_capability(dev, PCI_EXT_CAP_ID_ARI, PCI_ARI_VER,
931                         offset, PCI_ARI_SIZEOF);
932     pci_set_long(dev->config + offset + PCI_ARI_CAP, (nextfn & 0xff) << 8);
933 }
934 
935 void pcie_dev_ser_num_init(PCIDevice *dev, uint16_t offset, uint64_t ser_num)
936 {
937     static const int pci_dsn_ver = 1;
938     static const int pci_dsn_cap = 4;
939 
940     pcie_add_capability(dev, PCI_EXT_CAP_ID_DSN, pci_dsn_ver, offset,
941                         PCI_EXT_CAP_DSN_SIZEOF);
942     pci_set_quad(dev->config + offset + pci_dsn_cap, ser_num);
943 }
944 
945 void pcie_ats_init(PCIDevice *dev, uint16_t offset)
946 {
947     pcie_add_capability(dev, PCI_EXT_CAP_ID_ATS, 0x1,
948                         offset, PCI_EXT_CAP_ATS_SIZEOF);
949 
950     dev->exp.ats_cap = offset;
951 
952     /* Invalidate Queue Depth 0, Page Aligned Request 0 */
953     pci_set_word(dev->config + offset + PCI_ATS_CAP, 0);
954     /* STU 0, Disabled by default */
955     pci_set_word(dev->config + offset + PCI_ATS_CTRL, 0);
956 
957     pci_set_word(dev->wmask + dev->exp.ats_cap + PCI_ATS_CTRL, 0x800f);
958 }
959 
960 /* ACS (Access Control Services) */
961 void pcie_acs_init(PCIDevice *dev, uint16_t offset)
962 {
963     bool is_downstream = pci_is_express_downstream_port(dev);
964     uint16_t cap_bits = 0;
965 
966     /* For endpoints, only multifunction devs may have an ACS capability: */
967     assert(is_downstream ||
968            (dev->cap_present & QEMU_PCI_CAP_MULTIFUNCTION) ||
969            PCI_FUNC(dev->devfn));
970 
971     pcie_add_capability(dev, PCI_EXT_CAP_ID_ACS, PCI_ACS_VER, offset,
972                         PCI_ACS_SIZEOF);
973     dev->exp.acs_cap = offset;
974 
975     if (is_downstream) {
976         /*
977          * Downstream ports must implement SV, TB, RR, CR, UF, and DT (with
978          * caveats on the latter four that we ignore for simplicity).
979          * Endpoints may also implement a subset of ACS capabilities,
980          * but these are optional if the endpoint does not support
981          * peer-to-peer between functions and thus omitted here.
982          */
983         cap_bits = PCI_ACS_SV | PCI_ACS_TB | PCI_ACS_RR |
984             PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_DT;
985     }
986 
987     pci_set_word(dev->config + offset + PCI_ACS_CAP, cap_bits);
988     pci_set_word(dev->wmask + offset + PCI_ACS_CTRL, cap_bits);
989 }
990 
991 void pcie_acs_reset(PCIDevice *dev)
992 {
993     if (dev->exp.acs_cap) {
994         pci_set_word(dev->config + dev->exp.acs_cap + PCI_ACS_CTRL, 0);
995     }
996 }
997