xref: /openbmc/qemu/hw/pci/pcie_sriov.c (revision b9c0a2e0)
1 /*
2  * pcie_sriov.c:
3  *
4  * Implementation of SR/IOV emulation support.
5  *
6  * Copyright (c) 2015-2017 Knut Omang <knut.omang@oracle.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or later.
9  * See the COPYING file in the top-level directory.
10  *
11  */
12 
13 #include "qemu/osdep.h"
14 #include "hw/pci/pci_device.h"
15 #include "hw/pci/pcie.h"
16 #include "hw/pci/pci_bus.h"
17 #include "hw/qdev-properties.h"
18 #include "qemu/error-report.h"
19 #include "qemu/range.h"
20 #include "qapi/error.h"
21 #include "trace.h"
22 
23 static GHashTable *pfs;
24 
25 static void unparent_vfs(PCIDevice *dev, uint16_t total_vfs)
26 {
27     for (uint16_t i = 0; i < total_vfs; i++) {
28         PCIDevice *vf = dev->exp.sriov_pf.vf[i];
29         object_unparent(OBJECT(vf));
30         object_unref(OBJECT(vf));
31     }
32     g_free(dev->exp.sriov_pf.vf);
33     dev->exp.sriov_pf.vf = NULL;
34 }
35 
36 static void clear_ctrl_vfe(PCIDevice *dev)
37 {
38     uint8_t *ctrl = dev->config + dev->exp.sriov_cap + PCI_SRIOV_CTRL;
39     pci_set_word(ctrl, pci_get_word(ctrl) & ~PCI_SRIOV_CTRL_VFE);
40 }
41 
42 static void register_vfs(PCIDevice *dev)
43 {
44     uint16_t num_vfs;
45     uint16_t i;
46     uint16_t sriov_cap = dev->exp.sriov_cap;
47 
48     assert(sriov_cap > 0);
49     num_vfs = pci_get_word(dev->config + sriov_cap + PCI_SRIOV_NUM_VF);
50     if (num_vfs > pci_get_word(dev->config + sriov_cap + PCI_SRIOV_TOTAL_VF)) {
51         clear_ctrl_vfe(dev);
52         return;
53     }
54 
55     trace_sriov_register_vfs(dev->name, PCI_SLOT(dev->devfn),
56                              PCI_FUNC(dev->devfn), num_vfs);
57     for (i = 0; i < num_vfs; i++) {
58         pci_set_enabled(dev->exp.sriov_pf.vf[i], true);
59     }
60 }
61 
62 static void unregister_vfs(PCIDevice *dev)
63 {
64     uint16_t i;
65     uint8_t *cfg = dev->config + dev->exp.sriov_cap;
66 
67     trace_sriov_unregister_vfs(dev->name, PCI_SLOT(dev->devfn),
68                                PCI_FUNC(dev->devfn));
69     for (i = 0; i < pci_get_word(cfg + PCI_SRIOV_TOTAL_VF); i++) {
70         pci_set_enabled(dev->exp.sriov_pf.vf[i], false);
71     }
72 }
73 
74 static bool pcie_sriov_pf_init_common(PCIDevice *dev, uint16_t offset,
75                                       uint16_t vf_dev_id, uint16_t init_vfs,
76                                       uint16_t total_vfs, uint16_t vf_offset,
77                                       uint16_t vf_stride, Error **errp)
78 {
79     uint8_t *cfg = dev->config + offset;
80     uint8_t *wmask;
81 
82     if (!pci_is_express(dev)) {
83         error_setg(errp, "PCI Express is required for SR-IOV PF");
84         return false;
85     }
86 
87     if (pci_is_vf(dev)) {
88         error_setg(errp, "a device cannot be both an SR-IOV PF and a VF");
89         return false;
90     }
91 
92     if (total_vfs) {
93         uint16_t ari_cap = pcie_find_capability(dev, PCI_EXT_CAP_ID_ARI);
94         uint16_t first_vf_devfn = dev->devfn + vf_offset;
95         uint16_t last_vf_devfn = first_vf_devfn + vf_stride * (total_vfs - 1);
96 
97         if ((!ari_cap && PCI_SLOT(dev->devfn) != PCI_SLOT(last_vf_devfn)) ||
98             last_vf_devfn >= PCI_DEVFN_MAX) {
99             error_setg(errp, "VF function number overflows");
100             return false;
101         }
102     }
103 
104     pcie_add_capability(dev, PCI_EXT_CAP_ID_SRIOV, 1,
105                         offset, PCI_EXT_CAP_SRIOV_SIZEOF);
106     dev->exp.sriov_cap = offset;
107     dev->exp.sriov_pf.vf = NULL;
108 
109     pci_set_word(cfg + PCI_SRIOV_VF_OFFSET, vf_offset);
110     pci_set_word(cfg + PCI_SRIOV_VF_STRIDE, vf_stride);
111 
112     /*
113      * Mandatory page sizes to support.
114      * Device implementations can call pcie_sriov_pf_add_sup_pgsize()
115      * to set more bits:
116      */
117     pci_set_word(cfg + PCI_SRIOV_SUP_PGSIZE, SRIOV_SUP_PGSIZE_MINREQ);
118 
119     /*
120      * Default is to use 4K pages, software can modify it
121      * to any of the supported bits
122      */
123     pci_set_word(cfg + PCI_SRIOV_SYS_PGSIZE, 0x1);
124 
125     /* Set up device ID and initial/total number of VFs available */
126     pci_set_word(cfg + PCI_SRIOV_VF_DID, vf_dev_id);
127     pci_set_word(cfg + PCI_SRIOV_INITIAL_VF, init_vfs);
128     pci_set_word(cfg + PCI_SRIOV_TOTAL_VF, total_vfs);
129     pci_set_word(cfg + PCI_SRIOV_NUM_VF, 0);
130 
131     /* Write enable control bits */
132     wmask = dev->wmask + offset;
133     pci_set_word(wmask + PCI_SRIOV_CTRL,
134                  PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE | PCI_SRIOV_CTRL_ARI);
135     pci_set_word(wmask + PCI_SRIOV_NUM_VF, 0xffff);
136     pci_set_word(wmask + PCI_SRIOV_SYS_PGSIZE, 0x553);
137 
138     qdev_prop_set_bit(&dev->qdev, "multifunction", true);
139 
140     return true;
141 }
142 
143 bool pcie_sriov_pf_init(PCIDevice *dev, uint16_t offset,
144                         const char *vfname, uint16_t vf_dev_id,
145                         uint16_t init_vfs, uint16_t total_vfs,
146                         uint16_t vf_offset, uint16_t vf_stride,
147                         Error **errp)
148 {
149     BusState *bus = qdev_get_parent_bus(&dev->qdev);
150     int32_t devfn = dev->devfn + vf_offset;
151 
152     if (pfs && g_hash_table_contains(pfs, dev->qdev.id)) {
153         error_setg(errp, "attaching user-created SR-IOV VF unsupported");
154         return false;
155     }
156 
157     if (!pcie_sriov_pf_init_common(dev, offset, vf_dev_id, init_vfs,
158                                    total_vfs, vf_offset, vf_stride, errp)) {
159         return false;
160     }
161 
162     dev->exp.sriov_pf.vf = g_new(PCIDevice *, total_vfs);
163 
164     for (uint16_t i = 0; i < total_vfs; i++) {
165         PCIDevice *vf = pci_new(devfn, vfname);
166         vf->exp.sriov_vf.pf = dev;
167         vf->exp.sriov_vf.vf_number = i;
168 
169         if (!qdev_realize(&vf->qdev, bus, errp)) {
170             object_unparent(OBJECT(vf));
171             object_unref(vf);
172             unparent_vfs(dev, i);
173             return false;
174         }
175 
176         /* set vid/did according to sr/iov spec - they are not used */
177         pci_config_set_vendor_id(vf->config, 0xffff);
178         pci_config_set_device_id(vf->config, 0xffff);
179 
180         dev->exp.sriov_pf.vf[i] = vf;
181         devfn += vf_stride;
182     }
183 
184     return true;
185 }
186 
187 void pcie_sriov_pf_exit(PCIDevice *dev)
188 {
189     uint8_t *cfg = dev->config + dev->exp.sriov_cap;
190 
191     if (dev->exp.sriov_pf.vf_user_created) {
192         uint16_t ven_id = pci_get_word(dev->config + PCI_VENDOR_ID);
193         uint16_t total_vfs = pci_get_word(dev->config + PCI_SRIOV_TOTAL_VF);
194         uint16_t vf_dev_id = pci_get_word(dev->config + PCI_SRIOV_VF_DID);
195 
196         unregister_vfs(dev);
197 
198         for (uint16_t i = 0; i < total_vfs; i++) {
199             PCIDevice *vf = dev->exp.sriov_pf.vf[i];
200 
201             vf->exp.sriov_vf.pf = NULL;
202 
203             pci_config_set_vendor_id(vf->config, ven_id);
204             pci_config_set_device_id(vf->config, vf_dev_id);
205         }
206     } else {
207         unparent_vfs(dev, pci_get_word(cfg + PCI_SRIOV_TOTAL_VF));
208     }
209 }
210 
211 void pcie_sriov_pf_init_vf_bar(PCIDevice *dev, int region_num,
212                                uint8_t type, dma_addr_t size)
213 {
214     uint32_t addr;
215     uint64_t wmask;
216     uint16_t sriov_cap = dev->exp.sriov_cap;
217 
218     assert(sriov_cap > 0);
219     assert(region_num >= 0);
220     assert(region_num < PCI_NUM_REGIONS);
221     assert(region_num != PCI_ROM_SLOT);
222 
223     wmask = ~(size - 1);
224     addr = sriov_cap + PCI_SRIOV_BAR + region_num * 4;
225 
226     pci_set_long(dev->config + addr, type);
227     if (!(type & PCI_BASE_ADDRESS_SPACE_IO) &&
228         type & PCI_BASE_ADDRESS_MEM_TYPE_64) {
229         pci_set_quad(dev->wmask + addr, wmask);
230         pci_set_quad(dev->cmask + addr, ~0ULL);
231     } else {
232         pci_set_long(dev->wmask + addr, wmask & 0xffffffff);
233         pci_set_long(dev->cmask + addr, 0xffffffff);
234     }
235     dev->exp.sriov_pf.vf_bar_type[region_num] = type;
236 }
237 
238 void pcie_sriov_vf_register_bar(PCIDevice *dev, int region_num,
239                                 MemoryRegion *memory)
240 {
241     uint8_t type;
242 
243     assert(dev->exp.sriov_vf.pf);
244     type = dev->exp.sriov_vf.pf->exp.sriov_pf.vf_bar_type[region_num];
245 
246     return pci_register_bar(dev, region_num, type, memory);
247 }
248 
249 static gint compare_vf_devfns(gconstpointer a, gconstpointer b)
250 {
251     return (*(PCIDevice **)a)->devfn - (*(PCIDevice **)b)->devfn;
252 }
253 
254 int16_t pcie_sriov_pf_init_from_user_created_vfs(PCIDevice *dev,
255                                                  uint16_t offset,
256                                                  Error **errp)
257 {
258     GPtrArray *pf;
259     PCIDevice **vfs;
260     BusState *bus = qdev_get_parent_bus(DEVICE(dev));
261     uint16_t ven_id = pci_get_word(dev->config + PCI_VENDOR_ID);
262     uint16_t vf_dev_id;
263     uint16_t vf_offset;
264     uint16_t vf_stride;
265     uint16_t i;
266 
267     if (!pfs || !dev->qdev.id) {
268         return 0;
269     }
270 
271     pf = g_hash_table_lookup(pfs, dev->qdev.id);
272     if (!pf) {
273         return 0;
274     }
275 
276     if (pf->len > UINT16_MAX) {
277         error_setg(errp, "too many VFs");
278         return -1;
279     }
280 
281     g_ptr_array_sort(pf, compare_vf_devfns);
282     vfs = (void *)pf->pdata;
283 
284     if (vfs[0]->devfn <= dev->devfn) {
285         error_setg(errp, "a VF function number is less than the PF function number");
286         return -1;
287     }
288 
289     vf_dev_id = pci_get_word(vfs[0]->config + PCI_DEVICE_ID);
290     vf_offset = vfs[0]->devfn - dev->devfn;
291     vf_stride = pf->len < 2 ? 0 : vfs[1]->devfn - vfs[0]->devfn;
292 
293     for (i = 0; i < pf->len; i++) {
294         if (bus != qdev_get_parent_bus(&vfs[i]->qdev)) {
295             error_setg(errp, "SR-IOV VF parent bus mismatches with PF");
296             return -1;
297         }
298 
299         if (ven_id != pci_get_word(vfs[i]->config + PCI_VENDOR_ID)) {
300             error_setg(errp, "SR-IOV VF vendor ID mismatches with PF");
301             return -1;
302         }
303 
304         if (vf_dev_id != pci_get_word(vfs[i]->config + PCI_DEVICE_ID)) {
305             error_setg(errp, "inconsistent SR-IOV VF device IDs");
306             return -1;
307         }
308 
309         for (size_t j = 0; j < PCI_NUM_REGIONS; j++) {
310             if (vfs[i]->io_regions[j].size != vfs[0]->io_regions[j].size ||
311                 vfs[i]->io_regions[j].type != vfs[0]->io_regions[j].type) {
312                 error_setg(errp, "inconsistent SR-IOV BARs");
313                 return -1;
314             }
315         }
316 
317         if (vfs[i]->devfn - vfs[0]->devfn != vf_stride * i) {
318             error_setg(errp, "inconsistent SR-IOV stride");
319             return -1;
320         }
321     }
322 
323     if (!pcie_sriov_pf_init_common(dev, offset, vf_dev_id, pf->len,
324                                    pf->len, vf_offset, vf_stride, errp)) {
325         return -1;
326     }
327 
328     for (i = 0; i < pf->len; i++) {
329         vfs[i]->exp.sriov_vf.pf = dev;
330         vfs[i]->exp.sriov_vf.vf_number = i;
331 
332         /* set vid/did according to sr/iov spec - they are not used */
333         pci_config_set_vendor_id(vfs[i]->config, 0xffff);
334         pci_config_set_device_id(vfs[i]->config, 0xffff);
335     }
336 
337     dev->exp.sriov_pf.vf = vfs;
338     dev->exp.sriov_pf.vf_user_created = true;
339 
340     for (i = 0; i < PCI_NUM_REGIONS; i++) {
341         PCIIORegion *region = &vfs[0]->io_regions[i];
342 
343         if (region->size) {
344             pcie_sriov_pf_init_vf_bar(dev, i, region->type, region->size);
345         }
346     }
347 
348     return PCI_EXT_CAP_SRIOV_SIZEOF;
349 }
350 
351 bool pcie_sriov_register_device(PCIDevice *dev, Error **errp)
352 {
353     if (!dev->exp.sriov_pf.vf && dev->qdev.id &&
354         pfs && g_hash_table_contains(pfs, dev->qdev.id)) {
355         error_setg(errp, "attaching user-created SR-IOV VF unsupported");
356         return false;
357     }
358 
359     if (dev->sriov_pf) {
360         PCIDevice *pci_pf;
361         GPtrArray *pf;
362 
363         if (!PCI_DEVICE_GET_CLASS(dev)->sriov_vf_user_creatable) {
364             error_setg(errp, "user cannot create SR-IOV VF with this device type");
365             return false;
366         }
367 
368         if (!pci_is_express(dev)) {
369             error_setg(errp, "PCI Express is required for SR-IOV VF");
370             return false;
371         }
372 
373         if (!pci_qdev_find_device(dev->sriov_pf, &pci_pf)) {
374             error_setg(errp, "PCI device specified as SR-IOV PF already exists");
375             return false;
376         }
377 
378         if (!pfs) {
379             pfs = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);
380         }
381 
382         pf = g_hash_table_lookup(pfs, dev->sriov_pf);
383         if (!pf) {
384             pf = g_ptr_array_new();
385             g_hash_table_insert(pfs, g_strdup(dev->sriov_pf), pf);
386         }
387 
388         g_ptr_array_add(pf, dev);
389     }
390 
391     return true;
392 }
393 
394 void pcie_sriov_unregister_device(PCIDevice *dev)
395 {
396     if (dev->sriov_pf && pfs) {
397         GPtrArray *pf = g_hash_table_lookup(pfs, dev->sriov_pf);
398 
399         if (pf) {
400             g_ptr_array_remove_fast(pf, dev);
401 
402             if (!pf->len) {
403                 g_hash_table_remove(pfs, dev->sriov_pf);
404                 g_ptr_array_free(pf, FALSE);
405             }
406         }
407     }
408 }
409 
410 void pcie_sriov_config_write(PCIDevice *dev, uint32_t address,
411                              uint32_t val, int len)
412 {
413     uint32_t off;
414     uint16_t sriov_cap = dev->exp.sriov_cap;
415 
416     if (!sriov_cap || address < sriov_cap) {
417         return;
418     }
419     off = address - sriov_cap;
420     if (off >= PCI_EXT_CAP_SRIOV_SIZEOF) {
421         return;
422     }
423 
424     trace_sriov_config_write(dev->name, PCI_SLOT(dev->devfn),
425                              PCI_FUNC(dev->devfn), off, val, len);
426 
427     if (range_covers_byte(off, len, PCI_SRIOV_CTRL)) {
428         if (val & PCI_SRIOV_CTRL_VFE) {
429             register_vfs(dev);
430         } else {
431             unregister_vfs(dev);
432         }
433     } else if (range_covers_byte(off, len, PCI_SRIOV_NUM_VF)) {
434         clear_ctrl_vfe(dev);
435         unregister_vfs(dev);
436     }
437 }
438 
439 void pcie_sriov_pf_post_load(PCIDevice *dev)
440 {
441     if (dev->exp.sriov_cap) {
442         register_vfs(dev);
443     }
444 }
445 
446 
447 /* Reset SR/IOV */
448 void pcie_sriov_pf_reset(PCIDevice *dev)
449 {
450     uint16_t sriov_cap = dev->exp.sriov_cap;
451     if (!sriov_cap) {
452         return;
453     }
454 
455     pci_set_word(dev->config + sriov_cap + PCI_SRIOV_CTRL, 0);
456     unregister_vfs(dev);
457 
458     pci_set_word(dev->config + sriov_cap + PCI_SRIOV_NUM_VF, 0);
459 
460     /*
461      * Default is to use 4K pages, software can modify it
462      * to any of the supported bits
463      */
464     pci_set_word(dev->config + sriov_cap + PCI_SRIOV_SYS_PGSIZE, 0x1);
465 
466     for (uint16_t i = 0; i < PCI_NUM_REGIONS; i++) {
467         pci_set_quad(dev->config + sriov_cap + PCI_SRIOV_BAR + i * 4,
468                      dev->exp.sriov_pf.vf_bar_type[i]);
469     }
470 }
471 
472 /* Add optional supported page sizes to the mask of supported page sizes */
473 void pcie_sriov_pf_add_sup_pgsize(PCIDevice *dev, uint16_t opt_sup_pgsize)
474 {
475     uint8_t *cfg = dev->config + dev->exp.sriov_cap;
476     uint8_t *wmask = dev->wmask + dev->exp.sriov_cap;
477 
478     uint16_t sup_pgsize = pci_get_word(cfg + PCI_SRIOV_SUP_PGSIZE);
479 
480     sup_pgsize |= opt_sup_pgsize;
481 
482     /*
483      * Make sure the new bits are set, and that system page size
484      * also can be set to any of the new values according to spec:
485      */
486     pci_set_word(cfg + PCI_SRIOV_SUP_PGSIZE, sup_pgsize);
487     pci_set_word(wmask + PCI_SRIOV_SYS_PGSIZE, sup_pgsize);
488 }
489 
490 
491 uint16_t pcie_sriov_vf_number(PCIDevice *dev)
492 {
493     assert(dev->exp.sriov_vf.pf);
494     return dev->exp.sriov_vf.vf_number;
495 }
496 
497 PCIDevice *pcie_sriov_get_pf(PCIDevice *dev)
498 {
499     return dev->exp.sriov_vf.pf;
500 }
501 
502 PCIDevice *pcie_sriov_get_vf_at_index(PCIDevice *dev, int n)
503 {
504     assert(!pci_is_vf(dev));
505     if (n < pcie_sriov_num_vfs(dev)) {
506         return dev->exp.sriov_pf.vf[n];
507     }
508     return NULL;
509 }
510 
511 uint16_t pcie_sriov_num_vfs(PCIDevice *dev)
512 {
513     uint16_t sriov_cap = dev->exp.sriov_cap;
514     uint8_t *cfg = dev->config + sriov_cap;
515 
516     return sriov_cap &&
517            (pci_get_word(cfg + PCI_SRIOV_CTRL) & PCI_SRIOV_CTRL_VFE) ?
518            pci_get_word(cfg + PCI_SRIOV_NUM_VF) : 0;
519 }
520