virtio.c revision 1.19.2.1 1 /* $NetBSD: virtio.c,v 1.19.2.1 2017/04/21 16:53:51 bouyer Exp $ */
2
3 /*
4 * Copyright (c) 2010 Minoura Makoto.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: virtio.c,v 1.19.2.1 2017/04/21 16:53:51 bouyer Exp $");
30
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kernel.h>
34 #include <sys/atomic.h>
35 #include <sys/bus.h>
36 #include <sys/device.h>
37 #include <sys/kmem.h>
38 #include <sys/module.h>
39
40 #include <dev/pci/pcidevs.h>
41 #include <dev/pci/pcireg.h>
42 #include <dev/pci/pcivar.h>
43
44 #define VIRTIO_PRIVATE
45
46 #include <dev/pci/virtioreg.h>
47 #include <dev/pci/virtiovar.h>
48
49 #define MINSEG_INDIRECT 2 /* use indirect if nsegs >= this value */
50
51 static int virtio_match(device_t, cfdata_t, void *);
52 static void virtio_attach(device_t, device_t, void *);
53 static int virtio_rescan(device_t, const char *, const int *);
54 static int virtio_detach(device_t, int);
55 static int virtio_intr(void *arg);
56 static int virtio_msix_queue_intr(void *);
57 static int virtio_msix_config_intr(void *);
58 static int virtio_setup_msix_vectors(struct virtio_softc *);
59 static int virtio_setup_msix_interrupts(struct virtio_softc *,
60 struct pci_attach_args *);
61 static int virtio_setup_intx_interrupt(struct virtio_softc *,
62 struct pci_attach_args *);
63 static int virtio_setup_interrupts(struct virtio_softc *);
64 static void virtio_free_interrupts(struct virtio_softc *);
65 static void virtio_soft_intr(void *arg);
66 static void virtio_init_vq(struct virtio_softc *,
67 struct virtqueue *, const bool);
68
69 CFATTACH_DECL3_NEW(virtio, sizeof(struct virtio_softc),
70 virtio_match, virtio_attach, virtio_detach, NULL, virtio_rescan, NULL,
71 DVF_DETACH_SHUTDOWN);
72
73 /* we use the legacy virtio spec, so the pci registers are host native
74 * byte order, not pci (i.e. LE) byte order */
75 static inline uint16_t
76 nbo_bus_space_read_2(bus_space_tag_t space, bus_space_handle_t handle,
77 bus_size_t offset)
78 {
79 return le16toh(bus_space_read_2(space, handle, offset));
80 }
81
82 static inline uint32_t
83 nbo_bus_space_read_4(bus_space_tag_t space, bus_space_handle_t handle,
84 bus_size_t offset)
85 {
86 return le32toh(bus_space_read_4(space, handle, offset));
87 }
88
89 static void
90 nbo_bus_space_write_2(bus_space_tag_t space, bus_space_handle_t handle,
91 bus_size_t offset, uint16_t value)
92 {
93 bus_space_write_2(space, handle, offset, htole16(value));
94 }
95
96 static void
97 nbo_bus_space_write_4(bus_space_tag_t space, bus_space_handle_t handle,
98 bus_size_t offset, uint32_t value)
99 {
100 bus_space_write_4(space, handle, offset, htole32(value));
101 }
102
103 /* some functions access registers at 4 byte offset for little/high halves */
104 #if BYTE_ORDER == BIG_ENDIAN
105 #define REG_HI_OFF 0
106 #define REG_LO_OFF 4
107 #else
108 #define REG_HI_OFF 4
109 #define REG_LO_OFF 0
110 #endif
111
112 static void
113 virtio_set_status(struct virtio_softc *sc, int status)
114 {
115 int old = 0;
116
117 if (status != 0)
118 old = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
119 VIRTIO_CONFIG_DEVICE_STATUS);
120 bus_space_write_1(sc->sc_iot, sc->sc_ioh, VIRTIO_CONFIG_DEVICE_STATUS,
121 status|old);
122 }
123
124 #define virtio_device_reset(sc) virtio_set_status((sc), 0)
125
126 static int
127 virtio_match(device_t parent, cfdata_t match, void *aux)
128 {
129 struct pci_attach_args *pa;
130
131 pa = (struct pci_attach_args *)aux;
132 switch (PCI_VENDOR(pa->pa_id)) {
133 case PCI_VENDOR_QUMRANET:
134 if ((PCI_PRODUCT_QUMRANET_VIRTIO_1000 <=
135 PCI_PRODUCT(pa->pa_id)) &&
136 (PCI_PRODUCT(pa->pa_id) <=
137 PCI_PRODUCT_QUMRANET_VIRTIO_103F))
138 return 1;
139 break;
140 }
141
142 return 0;
143 }
144
145 static const char *virtio_device_name[] = {
146 "Unknown (0)", /* 0 */
147 "Network", /* 1 */
148 "Block", /* 2 */
149 "Console", /* 3 */
150 "Entropy", /* 4 */
151 "Memory Balloon", /* 5 */
152 "I/O Memory", /* 6 */
153 "Remote Processor Messaging", /* 7 */
154 "SCSI", /* 8 */
155 "9P Transport", /* 9 */
156 "mac80211 wlan", /* 10 */
157 };
158 #define NDEVNAMES __arraycount(virtio_device_name)
159
160 #define VIRTIO_MSIX_CONFIG_VECTOR_INDEX 0
161 #define VIRTIO_MSIX_QUEUE_VECTOR_INDEX 1
162
163 static int
164 virtio_setup_msix_vectors(struct virtio_softc *sc)
165 {
166 int offset, vector, ret, qid;
167
168 offset = VIRTIO_CONFIG_MSI_CONFIG_VECTOR;
169 vector = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
170
171 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh, offset, vector);
172 ret = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh, offset);
173 aprint_debug_dev(sc->sc_dev, "expected=%d, actual=%d\n",
174 vector, ret);
175 if (ret != vector)
176 return -1;
177
178 for (qid = 0; qid < sc->sc_nvqs; qid++) {
179 offset = VIRTIO_CONFIG_QUEUE_SELECT;
180 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh, offset, qid);
181
182 offset = VIRTIO_CONFIG_MSI_QUEUE_VECTOR;
183 vector = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
184
185 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh, offset, vector);
186 ret = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh, offset);
187 aprint_debug_dev(sc->sc_dev, "expected=%d, actual=%d\n",
188 vector, ret);
189 if (ret != vector)
190 return -1;
191 }
192
193 return 0;
194 }
195
196 static int
197 virtio_setup_msix_interrupts(struct virtio_softc *sc,
198 struct pci_attach_args *pa)
199 {
200 device_t self = sc->sc_dev;
201 pci_chipset_tag_t pc = pa->pa_pc;
202 char intrbuf[PCI_INTRSTR_LEN];
203 char const *intrstr;
204 int idx;
205
206 idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
207 if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
208 pci_intr_setattr(pc, &sc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
209
210 sc->sc_ihs[idx] = pci_intr_establish_xname(pc, sc->sc_ihp[idx],
211 sc->sc_ipl, virtio_msix_config_intr, sc, device_xname(sc->sc_dev));
212 if (sc->sc_ihs[idx] == NULL) {
213 aprint_error_dev(self, "couldn't establish MSI-X for config\n");
214 goto error;
215 }
216
217 idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
218 if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
219 pci_intr_setattr(pc, &sc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
220
221 sc->sc_ihs[idx] = pci_intr_establish_xname(pc, sc->sc_ihp[idx],
222 sc->sc_ipl, virtio_msix_queue_intr, sc, device_xname(sc->sc_dev));
223 if (sc->sc_ihs[idx] == NULL) {
224 aprint_error_dev(self, "couldn't establish MSI-X for queues\n");
225 goto error;
226 }
227
228 if (virtio_setup_msix_vectors(sc) != 0) {
229 aprint_error_dev(self, "couldn't setup MSI-X vectors\n");
230 goto error;
231 }
232
233 idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
234 intrstr = pci_intr_string(pc, sc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
235 aprint_normal_dev(self, "config interrupting at %s\n", intrstr);
236 idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
237 intrstr = pci_intr_string(pc, sc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
238 aprint_normal_dev(self, "queues interrupting at %s\n", intrstr);
239
240 return 0;
241
242 error:
243 idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
244 if (sc->sc_ihs[idx] != NULL)
245 pci_intr_disestablish(sc->sc_pc, sc->sc_ihs[idx]);
246 idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
247 if (sc->sc_ihs[idx] != NULL)
248 pci_intr_disestablish(sc->sc_pc, sc->sc_ihs[idx]);
249
250 return -1;
251 }
252
253 static int
254 virtio_setup_intx_interrupt(struct virtio_softc *sc,
255 struct pci_attach_args *pa)
256 {
257 device_t self = sc->sc_dev;
258 pci_chipset_tag_t pc = pa->pa_pc;
259 char intrbuf[PCI_INTRSTR_LEN];
260 char const *intrstr;
261
262 if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
263 pci_intr_setattr(pc, &sc->sc_ihp[0], PCI_INTR_MPSAFE, true);
264
265 sc->sc_ihs[0] = pci_intr_establish_xname(pc, sc->sc_ihp[0],
266 sc->sc_ipl, virtio_intr, sc, device_xname(sc->sc_dev));
267 if (sc->sc_ihs[0] == NULL) {
268 aprint_error_dev(self, "couldn't establish INTx\n");
269 return -1;
270 }
271
272 intrstr = pci_intr_string(pc, sc->sc_ihp[0], intrbuf, sizeof(intrbuf));
273 aprint_normal_dev(self, "interrupting at %s\n", intrstr);
274
275 return 0;
276 }
277
278 static int
279 virtio_setup_interrupts(struct virtio_softc *sc)
280 {
281 device_t self = sc->sc_dev;
282 pci_chipset_tag_t pc = sc->sc_pa.pa_pc;
283 int error;
284 int nmsix;
285 int counts[PCI_INTR_TYPE_SIZE];
286 pci_intr_type_t max_type;
287
288 nmsix = pci_msix_count(sc->sc_pa.pa_pc, sc->sc_pa.pa_tag);
289 aprint_debug_dev(self, "pci_msix_count=%d\n", nmsix);
290
291 /* We need at least two: one for config and the other for queues */
292 if ((sc->sc_flags & VIRTIO_F_PCI_INTR_MSIX) == 0 || nmsix < 2) {
293 /* Try INTx only */
294 max_type = PCI_INTR_TYPE_INTX;
295 counts[PCI_INTR_TYPE_INTX] = 1;
296 } else {
297 /* Try MSI-X first and INTx second */
298 max_type = PCI_INTR_TYPE_MSIX;
299 counts[PCI_INTR_TYPE_MSIX] = 2;
300 counts[PCI_INTR_TYPE_MSI] = 0;
301 counts[PCI_INTR_TYPE_INTX] = 1;
302 }
303
304 retry:
305 error = pci_intr_alloc(&sc->sc_pa, &sc->sc_ihp, counts, max_type);
306 if (error != 0) {
307 aprint_error_dev(self, "couldn't map interrupt\n");
308 return -1;
309 }
310
311 if (pci_intr_type(pc, sc->sc_ihp[0]) == PCI_INTR_TYPE_MSIX) {
312 sc->sc_ihs = kmem_alloc(sizeof(*sc->sc_ihs) * 2,
313 KM_SLEEP);
314 if (sc->sc_ihs == NULL) {
315 pci_intr_release(pc, sc->sc_ihp, 2);
316
317 /* Retry INTx */
318 max_type = PCI_INTR_TYPE_INTX;
319 counts[PCI_INTR_TYPE_INTX] = 1;
320 goto retry;
321 }
322
323 error = virtio_setup_msix_interrupts(sc, &sc->sc_pa);
324 if (error != 0) {
325 kmem_free(sc->sc_ihs, sizeof(*sc->sc_ihs) * 2);
326 pci_intr_release(pc, sc->sc_ihp, 2);
327
328 /* Retry INTx */
329 max_type = PCI_INTR_TYPE_INTX;
330 counts[PCI_INTR_TYPE_INTX] = 1;
331 goto retry;
332 }
333
334 sc->sc_ihs_num = 2;
335 sc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_MSI;
336 } else if (pci_intr_type(pc, sc->sc_ihp[0]) == PCI_INTR_TYPE_INTX) {
337 sc->sc_ihs = kmem_alloc(sizeof(*sc->sc_ihs) * 1,
338 KM_SLEEP);
339 if (sc->sc_ihs == NULL) {
340 pci_intr_release(pc, sc->sc_ihp, 1);
341 return -1;
342 }
343
344 error = virtio_setup_intx_interrupt(sc, &sc->sc_pa);
345 if (error != 0) {
346 kmem_free(sc->sc_ihs, sizeof(*sc->sc_ihs) * 1);
347 pci_intr_release(pc, sc->sc_ihp, 1);
348 return -1;
349 }
350
351 sc->sc_ihs_num = 1;
352 sc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
353 }
354
355 KASSERT(sc->sc_soft_ih == NULL);
356 if (sc->sc_flags & VIRTIO_F_PCI_INTR_SOFTINT) {
357 u_int flags = SOFTINT_NET;
358 if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
359 flags |= SOFTINT_MPSAFE;
360
361 sc->sc_soft_ih = softint_establish(flags, virtio_soft_intr, sc);
362 if (sc->sc_soft_ih == NULL) {
363 virtio_free_interrupts(sc);
364 aprint_error_dev(sc->sc_dev,
365 "failed to establish soft interrupt\n");
366 return -1;
367 }
368 }
369
370 return 0;
371 }
372
373 static void
374 virtio_free_interrupts(struct virtio_softc *sc)
375 {
376 for (int i = 0; i < sc->sc_ihs_num; i++) {
377 if (sc->sc_ihs[i] == NULL)
378 continue;
379 pci_intr_disestablish(sc->sc_pc, sc->sc_ihs[i]);
380 sc->sc_ihs[i] = NULL;
381 }
382
383 if (sc->sc_ihs_num > 0)
384 pci_intr_release(sc->sc_pc, sc->sc_ihp, sc->sc_ihs_num);
385
386 if (sc->sc_soft_ih) {
387 softint_disestablish(sc->sc_soft_ih);
388 sc->sc_soft_ih = NULL;
389 }
390
391 if (sc->sc_ihs != NULL) {
392 kmem_free(sc->sc_ihs, sizeof(*sc->sc_ihs) * sc->sc_ihs_num);
393 sc->sc_ihs = NULL;
394 }
395 sc->sc_ihs_num = 0;
396 }
397
398 static void
399 virtio_attach(device_t parent, device_t self, void *aux)
400 {
401 struct virtio_softc *sc = device_private(self);
402 struct pci_attach_args *pa = (struct pci_attach_args *)aux;
403 pci_chipset_tag_t pc = pa->pa_pc;
404 pcitag_t tag = pa->pa_tag;
405 int revision;
406 pcireg_t id;
407
408 revision = PCI_REVISION(pa->pa_class);
409 if (revision != 0) {
410 aprint_normal(": unknown revision 0x%02x; giving up\n",
411 revision);
412 return;
413 }
414 aprint_normal("\n");
415 aprint_naive("\n");
416
417 /* subsystem ID shows what I am */
418 id = pci_conf_read(pc, tag, PCI_SUBSYS_ID_REG);
419 aprint_normal_dev(self, "Virtio %s Device (rev. 0x%02x)\n",
420 (PCI_SUBSYS_ID(id) < NDEVNAMES?
421 virtio_device_name[PCI_SUBSYS_ID(id)] : "Unknown"),
422 revision);
423
424 sc->sc_dev = self;
425 sc->sc_pc = pc;
426 sc->sc_tag = tag;
427 sc->sc_iot = pa->pa_iot;
428 if (pci_dma64_available(pa))
429 sc->sc_dmat = pa->pa_dmat64;
430 else
431 sc->sc_dmat = pa->pa_dmat;
432 sc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
433
434 if (pci_mapreg_map(pa, PCI_MAPREG_START, PCI_MAPREG_TYPE_IO, 0,
435 &sc->sc_iot, &sc->sc_ioh, NULL, &sc->sc_iosize)) {
436 aprint_error_dev(self, "can't map i/o space\n");
437 return;
438 }
439
440 virtio_device_reset(sc);
441 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_ACK);
442 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER);
443
444 sc->sc_childdevid = PCI_SUBSYS_ID(id);
445 sc->sc_child = NULL;
446 sc->sc_pa = *pa;
447 virtio_rescan(self, "virtio", 0);
448 return;
449 }
450
451 /* ARGSUSED */
452 static int
453 virtio_rescan(device_t self, const char *attr, const int *scan_flags)
454 {
455 struct virtio_softc *sc;
456 struct virtio_attach_args va;
457
458 sc = device_private(self);
459 if (sc->sc_child) /* Child already attached? */
460 return 0;
461
462 memset(&va, 0, sizeof(va));
463 va.sc_childdevid = sc->sc_childdevid;
464
465 config_found_ia(self, attr, &va, NULL);
466
467 if (sc->sc_child == NULL) {
468 aprint_error_dev(self,
469 "no matching child driver; not configured\n");
470 return 0;
471 }
472
473 if (sc->sc_child == VIRTIO_CHILD_FAILED) {
474 aprint_error_dev(self,
475 "virtio configuration failed\n");
476 return 0;
477 }
478
479 /*
480 * Make sure child drivers initialize interrupts via call
481 * to virtio_child_attach_finish().
482 */
483 KASSERT(sc->sc_ihs_num != 0);
484
485 return 0;
486 }
487
488 static int
489 virtio_detach(device_t self, int flags)
490 {
491 struct virtio_softc *sc = device_private(self);
492 int r;
493
494 if (sc->sc_child != NULL) {
495 r = config_detach(sc->sc_child, flags);
496 if (r)
497 return r;
498 }
499
500 /* Check that child detached properly */
501 KASSERT(sc->sc_child == NULL);
502 KASSERT(sc->sc_vqs == NULL);
503 KASSERT(sc->sc_ihs_num == 0);
504
505 if (sc->sc_iosize)
506 bus_space_unmap(sc->sc_iot, sc->sc_ioh, sc->sc_iosize);
507 sc->sc_iosize = 0;
508
509 return 0;
510 }
511
512 /*
513 * Reset the device.
514 */
515 /*
516 * To reset the device to a known state, do following:
517 * virtio_reset(sc); // this will stop the device activity
518 * <dequeue finished requests>; // virtio_dequeue() still can be called
519 * <revoke pending requests in the vqs if any>;
520 * virtio_reinit_begin(sc); // dequeue prohibitted
521 * newfeatures = virtio_negotiate_features(sc, requestedfeatures);
522 * <some other initialization>;
523 * virtio_reinit_end(sc); // device activated; enqueue allowed
524 * Once attached, feature negotiation can only be allowed after virtio_reset.
525 */
526 void
527 virtio_reset(struct virtio_softc *sc)
528 {
529 virtio_device_reset(sc);
530 }
531
532 void
533 virtio_reinit_start(struct virtio_softc *sc)
534 {
535 int i;
536
537 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_ACK);
538 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER);
539 for (i = 0; i < sc->sc_nvqs; i++) {
540 int n;
541 struct virtqueue *vq = &sc->sc_vqs[i];
542 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
543 VIRTIO_CONFIG_QUEUE_SELECT,
544 vq->vq_index);
545 n = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh,
546 VIRTIO_CONFIG_QUEUE_SIZE);
547 if (n == 0) /* vq disappeared */
548 continue;
549 if (n != vq->vq_num) {
550 panic("%s: virtqueue size changed, vq index %d\n",
551 device_xname(sc->sc_dev),
552 vq->vq_index);
553 }
554 virtio_init_vq(sc, vq, true);
555 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
556 VIRTIO_CONFIG_QUEUE_ADDRESS,
557 (vq->vq_dmamap->dm_segs[0].ds_addr
558 / VIRTIO_PAGE_SIZE));
559 }
560
561 /* MSI-X should have more than one handles where INTx has just one */
562 if (sc->sc_ihs_num > 1) {
563 if (virtio_setup_msix_vectors(sc) != 0) {
564 aprint_error_dev(sc->sc_dev,
565 "couldn't setup MSI-X vectors\n");
566 return;
567 }
568 }
569 }
570
571 void
572 virtio_reinit_end(struct virtio_softc *sc)
573 {
574 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER_OK);
575 }
576
577 /*
578 * Feature negotiation.
579 */
580 uint32_t
581 virtio_negotiate_features(struct virtio_softc *sc, uint32_t guest_features)
582 {
583 uint32_t r;
584
585 if (!(device_cfdata(sc->sc_dev)->cf_flags & 1) &&
586 !(device_cfdata(sc->sc_child)->cf_flags & 1)) /* XXX */
587 guest_features |= VIRTIO_F_RING_INDIRECT_DESC;
588 r = nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
589 VIRTIO_CONFIG_DEVICE_FEATURES);
590 r &= guest_features;
591 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
592 VIRTIO_CONFIG_GUEST_FEATURES, r);
593 sc->sc_features = r;
594 if (r & VIRTIO_F_RING_INDIRECT_DESC)
595 sc->sc_indirect = true;
596 else
597 sc->sc_indirect = false;
598
599 return r;
600 }
601
602 /*
603 * Device configuration registers.
604 */
605 uint8_t
606 virtio_read_device_config_1(struct virtio_softc *sc, int index)
607 {
608 return bus_space_read_1(sc->sc_iot, sc->sc_ioh,
609 sc->sc_config_offset + index);
610 }
611
612 uint16_t
613 virtio_read_device_config_2(struct virtio_softc *sc, int index)
614 {
615 return nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh,
616 sc->sc_config_offset + index);
617 }
618
619 uint32_t
620 virtio_read_device_config_4(struct virtio_softc *sc, int index)
621 {
622 return nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
623 sc->sc_config_offset + index);
624 }
625
626 uint64_t
627 virtio_read_device_config_8(struct virtio_softc *sc, int index)
628 {
629 uint64_t r;
630
631 r = nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
632 sc->sc_config_offset + index + REG_HI_OFF);
633 r <<= 32;
634 r |= nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
635 sc->sc_config_offset + index + REG_LO_OFF);
636
637 return r;
638 }
639
640 void
641 virtio_write_device_config_1(struct virtio_softc *sc,
642 int index, uint8_t value)
643 {
644 bus_space_write_1(sc->sc_iot, sc->sc_ioh,
645 sc->sc_config_offset + index, value);
646 }
647
648 void
649 virtio_write_device_config_2(struct virtio_softc *sc,
650 int index, uint16_t value)
651 {
652 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
653 sc->sc_config_offset + index, value);
654 }
655
656 void
657 virtio_write_device_config_4(struct virtio_softc *sc,
658 int index, uint32_t value)
659 {
660 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
661 sc->sc_config_offset + index, value);
662 }
663
664 void
665 virtio_write_device_config_8(struct virtio_softc *sc,
666 int index, uint64_t value)
667 {
668 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
669 sc->sc_config_offset + index + REG_LO_OFF,
670 value & 0xffffffff);
671 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
672 sc->sc_config_offset + index + REG_HI_OFF,
673 value >> 32);
674 }
675
676 /*
677 * Interrupt handler.
678 */
679 static int
680 virtio_intr(void *arg)
681 {
682 struct virtio_softc *sc = arg;
683 int isr, r = 0;
684
685 /* check and ack the interrupt */
686 isr = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
687 VIRTIO_CONFIG_ISR_STATUS);
688 if (isr == 0)
689 return 0;
690 if ((isr & VIRTIO_CONFIG_ISR_CONFIG_CHANGE) &&
691 (sc->sc_config_change != NULL))
692 r = (sc->sc_config_change)(sc);
693 if (sc->sc_intrhand != NULL) {
694 if (sc->sc_soft_ih != NULL)
695 softint_schedule(sc->sc_soft_ih);
696 else
697 r |= (sc->sc_intrhand)(sc);
698 }
699
700 return r;
701 }
702
703 static int
704 virtio_msix_queue_intr(void *arg)
705 {
706 struct virtio_softc *sc = arg;
707 int r = 0;
708
709 if (sc->sc_intrhand != NULL) {
710 if (sc->sc_soft_ih != NULL)
711 softint_schedule(sc->sc_soft_ih);
712 else
713 r |= (sc->sc_intrhand)(sc);
714 }
715
716 return r;
717 }
718
719 static int
720 virtio_msix_config_intr(void *arg)
721 {
722 struct virtio_softc *sc = arg;
723 int r = 0;
724
725 if (sc->sc_config_change != NULL)
726 r = (sc->sc_config_change)(sc);
727 return r;
728 }
729
730 static void
731 virtio_soft_intr(void *arg)
732 {
733 struct virtio_softc *sc = arg;
734
735 KASSERT(sc->sc_intrhand != NULL);
736
737 (sc->sc_intrhand)(sc);
738 }
739
740 /*
741 * dmamap sync operations for a virtqueue.
742 */
743 static inline void
744 vq_sync_descs(struct virtio_softc *sc, struct virtqueue *vq, int ops)
745 {
746 /* availoffset == sizeof(vring_desc)*vq_num */
747 bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap, 0, vq->vq_availoffset,
748 ops);
749 }
750
751 static inline void
752 vq_sync_aring(struct virtio_softc *sc, struct virtqueue *vq, int ops)
753 {
754 bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap,
755 vq->vq_availoffset,
756 offsetof(struct vring_avail, ring)
757 + vq->vq_num * sizeof(uint16_t),
758 ops);
759 }
760
761 static inline void
762 vq_sync_uring(struct virtio_softc *sc, struct virtqueue *vq, int ops)
763 {
764 bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap,
765 vq->vq_usedoffset,
766 offsetof(struct vring_used, ring)
767 + vq->vq_num * sizeof(struct vring_used_elem),
768 ops);
769 }
770
771 static inline void
772 vq_sync_indirect(struct virtio_softc *sc, struct virtqueue *vq, int slot,
773 int ops)
774 {
775 int offset = vq->vq_indirectoffset
776 + sizeof(struct vring_desc) * vq->vq_maxnsegs * slot;
777
778 bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap,
779 offset, sizeof(struct vring_desc) * vq->vq_maxnsegs,
780 ops);
781 }
782
783 /*
784 * Can be used as sc_intrhand.
785 */
786 /*
787 * Scan vq, bus_dmamap_sync for the vqs (not for the payload),
788 * and calls (*vq_done)() if some entries are consumed.
789 */
790 int
791 virtio_vq_intr(struct virtio_softc *sc)
792 {
793 struct virtqueue *vq;
794 int i, r = 0;
795
796 for (i = 0; i < sc->sc_nvqs; i++) {
797 vq = &sc->sc_vqs[i];
798 if (vq->vq_queued) {
799 vq->vq_queued = 0;
800 vq_sync_aring(sc, vq, BUS_DMASYNC_POSTWRITE);
801 }
802 vq_sync_uring(sc, vq, BUS_DMASYNC_POSTREAD);
803 membar_consumer();
804 if (vq->vq_used_idx != vq->vq_used->idx) {
805 if (vq->vq_done)
806 r |= (vq->vq_done)(vq);
807 }
808 }
809
810 return r;
811 }
812
813 /*
814 * Start/stop vq interrupt. No guarantee.
815 */
816 void
817 virtio_stop_vq_intr(struct virtio_softc *sc, struct virtqueue *vq)
818 {
819 vq->vq_avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
820 vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
821 vq->vq_queued++;
822 }
823
824 void
825 virtio_start_vq_intr(struct virtio_softc *sc, struct virtqueue *vq)
826 {
827 vq->vq_avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
828 vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
829 vq->vq_queued++;
830 }
831
832 /*
833 * Initialize vq structure.
834 */
835 static void
836 virtio_init_vq(struct virtio_softc *sc, struct virtqueue *vq,
837 const bool reinit)
838 {
839 int i, j;
840 int vq_size = vq->vq_num;
841
842 memset(vq->vq_vaddr, 0, vq->vq_bytesize);
843
844 /* build the indirect descriptor chain */
845 if (vq->vq_indirect != NULL) {
846 struct vring_desc *vd;
847
848 for (i = 0; i < vq_size; i++) {
849 vd = vq->vq_indirect;
850 vd += vq->vq_maxnsegs * i;
851 for (j = 0; j < vq->vq_maxnsegs-1; j++) {
852 vd[j].next = j + 1;
853 }
854 }
855 }
856
857 /* free slot management */
858 SIMPLEQ_INIT(&vq->vq_freelist);
859 for (i = 0; i < vq_size; i++) {
860 SIMPLEQ_INSERT_TAIL(&vq->vq_freelist,
861 &vq->vq_entries[i], qe_list);
862 vq->vq_entries[i].qe_index = i;
863 }
864 if (!reinit)
865 mutex_init(&vq->vq_freelist_lock, MUTEX_SPIN, sc->sc_ipl);
866
867 /* enqueue/dequeue status */
868 vq->vq_avail_idx = 0;
869 vq->vq_used_idx = 0;
870 vq->vq_queued = 0;
871 if (!reinit) {
872 mutex_init(&vq->vq_aring_lock, MUTEX_SPIN, sc->sc_ipl);
873 mutex_init(&vq->vq_uring_lock, MUTEX_SPIN, sc->sc_ipl);
874 }
875 vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
876 vq_sync_uring(sc, vq, BUS_DMASYNC_PREREAD);
877 vq->vq_queued++;
878 }
879
880 /*
881 * Allocate/free a vq.
882 */
883 int
884 virtio_alloc_vq(struct virtio_softc *sc, struct virtqueue *vq, int index,
885 int maxsegsize, int maxnsegs, const char *name)
886 {
887 int vq_size, allocsize1, allocsize2, allocsize3, allocsize = 0;
888 int rsegs, r;
889 #define VIRTQUEUE_ALIGN(n) (((n)+(VIRTIO_PAGE_SIZE-1))& \
890 ~(VIRTIO_PAGE_SIZE-1))
891
892 /* Make sure callers allocate vqs in order */
893 KASSERT(sc->sc_nvqs == index);
894
895 memset(vq, 0, sizeof(*vq));
896
897 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
898 VIRTIO_CONFIG_QUEUE_SELECT, index);
899 vq_size = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh,
900 VIRTIO_CONFIG_QUEUE_SIZE);
901 if (vq_size == 0) {
902 aprint_error_dev(sc->sc_dev,
903 "virtqueue not exist, index %d for %s\n",
904 index, name);
905 goto err;
906 }
907 /* allocsize1: descriptor table + avail ring + pad */
908 allocsize1 = VIRTQUEUE_ALIGN(sizeof(struct vring_desc)*vq_size
909 + sizeof(uint16_t)*(2+vq_size));
910 /* allocsize2: used ring + pad */
911 allocsize2 = VIRTQUEUE_ALIGN(sizeof(uint16_t)*2
912 + sizeof(struct vring_used_elem)*vq_size);
913 /* allocsize3: indirect table */
914 if (sc->sc_indirect && maxnsegs >= MINSEG_INDIRECT)
915 allocsize3 = sizeof(struct vring_desc) * maxnsegs * vq_size;
916 else
917 allocsize3 = 0;
918 allocsize = allocsize1 + allocsize2 + allocsize3;
919
920 /* alloc and map the memory */
921 r = bus_dmamem_alloc(sc->sc_dmat, allocsize, VIRTIO_PAGE_SIZE, 0,
922 &vq->vq_segs[0], 1, &rsegs, BUS_DMA_NOWAIT);
923 if (r != 0) {
924 aprint_error_dev(sc->sc_dev,
925 "virtqueue %d for %s allocation failed, "
926 "error code %d\n", index, name, r);
927 goto err;
928 }
929 r = bus_dmamem_map(sc->sc_dmat, &vq->vq_segs[0], 1, allocsize,
930 &vq->vq_vaddr, BUS_DMA_NOWAIT);
931 if (r != 0) {
932 aprint_error_dev(sc->sc_dev,
933 "virtqueue %d for %s map failed, "
934 "error code %d\n", index, name, r);
935 goto err;
936 }
937 r = bus_dmamap_create(sc->sc_dmat, allocsize, 1, allocsize, 0,
938 BUS_DMA_NOWAIT, &vq->vq_dmamap);
939 if (r != 0) {
940 aprint_error_dev(sc->sc_dev,
941 "virtqueue %d for %s dmamap creation failed, "
942 "error code %d\n", index, name, r);
943 goto err;
944 }
945 r = bus_dmamap_load(sc->sc_dmat, vq->vq_dmamap,
946 vq->vq_vaddr, allocsize, NULL, BUS_DMA_NOWAIT);
947 if (r != 0) {
948 aprint_error_dev(sc->sc_dev,
949 "virtqueue %d for %s dmamap load failed, "
950 "error code %d\n", index, name, r);
951 goto err;
952 }
953
954 /* set the vq address */
955 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
956 VIRTIO_CONFIG_QUEUE_ADDRESS,
957 (vq->vq_dmamap->dm_segs[0].ds_addr
958 / VIRTIO_PAGE_SIZE));
959
960 /* remember addresses and offsets for later use */
961 vq->vq_owner = sc;
962 vq->vq_num = vq_size;
963 vq->vq_index = index;
964 vq->vq_desc = vq->vq_vaddr;
965 vq->vq_availoffset = sizeof(struct vring_desc)*vq_size;
966 vq->vq_avail = (void*)(((char*)vq->vq_desc) + vq->vq_availoffset);
967 vq->vq_usedoffset = allocsize1;
968 vq->vq_used = (void*)(((char*)vq->vq_desc) + vq->vq_usedoffset);
969 if (allocsize3 > 0) {
970 vq->vq_indirectoffset = allocsize1 + allocsize2;
971 vq->vq_indirect = (void*)(((char*)vq->vq_desc)
972 + vq->vq_indirectoffset);
973 }
974 vq->vq_bytesize = allocsize;
975 vq->vq_maxsegsize = maxsegsize;
976 vq->vq_maxnsegs = maxnsegs;
977
978 /* free slot management */
979 vq->vq_entries = kmem_zalloc(sizeof(struct vq_entry)*vq_size,
980 KM_NOSLEEP);
981 if (vq->vq_entries == NULL) {
982 r = ENOMEM;
983 goto err;
984 }
985
986 virtio_init_vq(sc, vq, false);
987
988 aprint_verbose_dev(sc->sc_dev,
989 "allocated %u byte for virtqueue %d for %s, "
990 "size %d\n", allocsize, index, name, vq_size);
991 if (allocsize3 > 0)
992 aprint_verbose_dev(sc->sc_dev,
993 "using %d byte (%d entries) "
994 "indirect descriptors\n",
995 allocsize3, maxnsegs * vq_size);
996
997 sc->sc_nvqs++;
998
999 return 0;
1000
1001 err:
1002 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
1003 VIRTIO_CONFIG_QUEUE_ADDRESS, 0);
1004 if (vq->vq_dmamap)
1005 bus_dmamap_destroy(sc->sc_dmat, vq->vq_dmamap);
1006 if (vq->vq_vaddr)
1007 bus_dmamem_unmap(sc->sc_dmat, vq->vq_vaddr, allocsize);
1008 if (vq->vq_segs[0].ds_addr)
1009 bus_dmamem_free(sc->sc_dmat, &vq->vq_segs[0], 1);
1010 memset(vq, 0, sizeof(*vq));
1011
1012 return -1;
1013 }
1014
1015 int
1016 virtio_free_vq(struct virtio_softc *sc, struct virtqueue *vq)
1017 {
1018 struct vq_entry *qe;
1019 int i = 0;
1020
1021 /* device must be already deactivated */
1022 /* confirm the vq is empty */
1023 SIMPLEQ_FOREACH(qe, &vq->vq_freelist, qe_list) {
1024 i++;
1025 }
1026 if (i != vq->vq_num) {
1027 printf("%s: freeing non-empty vq, index %d\n",
1028 device_xname(sc->sc_dev), vq->vq_index);
1029 return EBUSY;
1030 }
1031
1032 /* tell device that there's no virtqueue any longer */
1033 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
1034 VIRTIO_CONFIG_QUEUE_SELECT, vq->vq_index);
1035 nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
1036 VIRTIO_CONFIG_QUEUE_ADDRESS, 0);
1037
1038 kmem_free(vq->vq_entries, sizeof(*vq->vq_entries) * vq->vq_num);
1039 bus_dmamap_unload(sc->sc_dmat, vq->vq_dmamap);
1040 bus_dmamap_destroy(sc->sc_dmat, vq->vq_dmamap);
1041 bus_dmamem_unmap(sc->sc_dmat, vq->vq_vaddr, vq->vq_bytesize);
1042 bus_dmamem_free(sc->sc_dmat, &vq->vq_segs[0], 1);
1043 mutex_destroy(&vq->vq_freelist_lock);
1044 mutex_destroy(&vq->vq_uring_lock);
1045 mutex_destroy(&vq->vq_aring_lock);
1046 memset(vq, 0, sizeof(*vq));
1047
1048 sc->sc_nvqs--;
1049
1050 return 0;
1051 }
1052
1053 /*
1054 * Free descriptor management.
1055 */
1056 static struct vq_entry *
1057 vq_alloc_entry(struct virtqueue *vq)
1058 {
1059 struct vq_entry *qe;
1060
1061 mutex_enter(&vq->vq_freelist_lock);
1062 if (SIMPLEQ_EMPTY(&vq->vq_freelist)) {
1063 mutex_exit(&vq->vq_freelist_lock);
1064 return NULL;
1065 }
1066 qe = SIMPLEQ_FIRST(&vq->vq_freelist);
1067 SIMPLEQ_REMOVE_HEAD(&vq->vq_freelist, qe_list);
1068 mutex_exit(&vq->vq_freelist_lock);
1069
1070 return qe;
1071 }
1072
1073 static void
1074 vq_free_entry(struct virtqueue *vq, struct vq_entry *qe)
1075 {
1076 mutex_enter(&vq->vq_freelist_lock);
1077 SIMPLEQ_INSERT_TAIL(&vq->vq_freelist, qe, qe_list);
1078 mutex_exit(&vq->vq_freelist_lock);
1079
1080 return;
1081 }
1082
1083 /*
1084 * Enqueue several dmamaps as a single request.
1085 */
1086 /*
1087 * Typical usage:
1088 * <queue size> number of followings are stored in arrays
1089 * - command blocks (in dmamem) should be pre-allocated and mapped
1090 * - dmamaps for command blocks should be pre-allocated and loaded
1091 * - dmamaps for payload should be pre-allocated
1092 * r = virtio_enqueue_prep(sc, vq, &slot); // allocate a slot
1093 * if (r) // currently 0 or EAGAIN
1094 * return r;
1095 * r = bus_dmamap_load(dmat, dmamap_payload[slot], data, count, ..);
1096 * if (r) {
1097 * virtio_enqueue_abort(sc, vq, slot);
1098 * return r;
1099 * }
1100 * r = virtio_enqueue_reserve(sc, vq, slot,
1101 * dmamap_payload[slot]->dm_nsegs+1);
1102 * // ^ +1 for command
1103 * if (r) { // currently 0 or EAGAIN
1104 * bus_dmamap_unload(dmat, dmamap_payload[slot]);
1105 * return r; // do not call abort()
1106 * }
1107 * <setup and prepare commands>
1108 * bus_dmamap_sync(dmat, dmamap_cmd[slot],... BUS_DMASYNC_PREWRITE);
1109 * bus_dmamap_sync(dmat, dmamap_payload[slot],...);
1110 * virtio_enqueue(sc, vq, slot, dmamap_cmd[slot], false);
1111 * virtio_enqueue(sc, vq, slot, dmamap_payload[slot], iswrite);
1112 * virtio_enqueue_commit(sc, vq, slot, true);
1113 */
1114
1115 /*
1116 * enqueue_prep: allocate a slot number
1117 */
1118 int
1119 virtio_enqueue_prep(struct virtio_softc *sc, struct virtqueue *vq, int *slotp)
1120 {
1121 struct vq_entry *qe1;
1122
1123 KASSERT(slotp != NULL);
1124
1125 qe1 = vq_alloc_entry(vq);
1126 if (qe1 == NULL)
1127 return EAGAIN;
1128 /* next slot is not allocated yet */
1129 qe1->qe_next = -1;
1130 *slotp = qe1->qe_index;
1131
1132 return 0;
1133 }
1134
1135 /*
1136 * enqueue_reserve: allocate remaining slots and build the descriptor chain.
1137 */
1138 int
1139 virtio_enqueue_reserve(struct virtio_softc *sc, struct virtqueue *vq,
1140 int slot, int nsegs)
1141 {
1142 int indirect;
1143 struct vq_entry *qe1 = &vq->vq_entries[slot];
1144
1145 KASSERT(qe1->qe_next == -1);
1146 KASSERT(1 <= nsegs && nsegs <= vq->vq_num);
1147
1148 if ((vq->vq_indirect != NULL) &&
1149 (nsegs >= MINSEG_INDIRECT) &&
1150 (nsegs <= vq->vq_maxnsegs))
1151 indirect = 1;
1152 else
1153 indirect = 0;
1154 qe1->qe_indirect = indirect;
1155
1156 if (indirect) {
1157 struct vring_desc *vd;
1158 int i;
1159
1160 vd = &vq->vq_desc[qe1->qe_index];
1161 vd->addr = vq->vq_dmamap->dm_segs[0].ds_addr
1162 + vq->vq_indirectoffset;
1163 vd->addr += sizeof(struct vring_desc)
1164 * vq->vq_maxnsegs * qe1->qe_index;
1165 vd->len = sizeof(struct vring_desc) * nsegs;
1166 vd->flags = VRING_DESC_F_INDIRECT;
1167
1168 vd = vq->vq_indirect;
1169 vd += vq->vq_maxnsegs * qe1->qe_index;
1170 qe1->qe_desc_base = vd;
1171
1172 for (i = 0; i < nsegs-1; i++) {
1173 vd[i].flags = VRING_DESC_F_NEXT;
1174 }
1175 vd[i].flags = 0;
1176 qe1->qe_next = 0;
1177
1178 return 0;
1179 } else {
1180 struct vring_desc *vd;
1181 struct vq_entry *qe;
1182 int i, s;
1183
1184 vd = &vq->vq_desc[0];
1185 qe1->qe_desc_base = vd;
1186 qe1->qe_next = qe1->qe_index;
1187 s = slot;
1188 for (i = 0; i < nsegs - 1; i++) {
1189 qe = vq_alloc_entry(vq);
1190 if (qe == NULL) {
1191 vd[s].flags = 0;
1192 virtio_enqueue_abort(sc, vq, slot);
1193 return EAGAIN;
1194 }
1195 vd[s].flags = VRING_DESC_F_NEXT;
1196 vd[s].next = qe->qe_index;
1197 s = qe->qe_index;
1198 }
1199 vd[s].flags = 0;
1200
1201 return 0;
1202 }
1203 }
1204
1205 /*
1206 * enqueue: enqueue a single dmamap.
1207 */
1208 int
1209 virtio_enqueue(struct virtio_softc *sc, struct virtqueue *vq, int slot,
1210 bus_dmamap_t dmamap, bool write)
1211 {
1212 struct vq_entry *qe1 = &vq->vq_entries[slot];
1213 struct vring_desc *vd = qe1->qe_desc_base;
1214 int i;
1215 int s = qe1->qe_next;
1216
1217 KASSERT(s >= 0);
1218 KASSERT(dmamap->dm_nsegs > 0);
1219
1220 for (i = 0; i < dmamap->dm_nsegs; i++) {
1221 vd[s].addr = dmamap->dm_segs[i].ds_addr;
1222 vd[s].len = dmamap->dm_segs[i].ds_len;
1223 if (!write)
1224 vd[s].flags |= VRING_DESC_F_WRITE;
1225 s = vd[s].next;
1226 }
1227 qe1->qe_next = s;
1228
1229 return 0;
1230 }
1231
1232 int
1233 virtio_enqueue_p(struct virtio_softc *sc, struct virtqueue *vq, int slot,
1234 bus_dmamap_t dmamap, bus_addr_t start, bus_size_t len,
1235 bool write)
1236 {
1237 struct vq_entry *qe1 = &vq->vq_entries[slot];
1238 struct vring_desc *vd = qe1->qe_desc_base;
1239 int s = qe1->qe_next;
1240
1241 KASSERT(s >= 0);
1242 KASSERT(dmamap->dm_nsegs == 1); /* XXX */
1243 KASSERT((dmamap->dm_segs[0].ds_len > start) &&
1244 (dmamap->dm_segs[0].ds_len >= start + len));
1245
1246 vd[s].addr = dmamap->dm_segs[0].ds_addr + start;
1247 vd[s].len = len;
1248 if (!write)
1249 vd[s].flags |= VRING_DESC_F_WRITE;
1250 qe1->qe_next = vd[s].next;
1251
1252 return 0;
1253 }
1254
1255 /*
1256 * enqueue_commit: add it to the aring.
1257 */
1258 int
1259 virtio_enqueue_commit(struct virtio_softc *sc, struct virtqueue *vq, int slot,
1260 bool notifynow)
1261 {
1262 struct vq_entry *qe1;
1263
1264 if (slot < 0) {
1265 mutex_enter(&vq->vq_aring_lock);
1266 goto notify;
1267 }
1268 vq_sync_descs(sc, vq, BUS_DMASYNC_PREWRITE);
1269 qe1 = &vq->vq_entries[slot];
1270 if (qe1->qe_indirect)
1271 vq_sync_indirect(sc, vq, slot, BUS_DMASYNC_PREWRITE);
1272 mutex_enter(&vq->vq_aring_lock);
1273 vq->vq_avail->ring[(vq->vq_avail_idx++) % vq->vq_num] = slot;
1274
1275 notify:
1276 if (notifynow) {
1277 vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
1278 vq_sync_uring(sc, vq, BUS_DMASYNC_PREREAD);
1279 membar_producer();
1280 vq->vq_avail->idx = vq->vq_avail_idx;
1281 vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
1282 membar_producer();
1283 vq->vq_queued++;
1284 vq_sync_uring(sc, vq, BUS_DMASYNC_POSTREAD);
1285 membar_consumer();
1286 if (!(vq->vq_used->flags & VRING_USED_F_NO_NOTIFY))
1287 nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
1288 VIRTIO_CONFIG_QUEUE_NOTIFY,
1289 vq->vq_index);
1290 }
1291 mutex_exit(&vq->vq_aring_lock);
1292
1293 return 0;
1294 }
1295
1296 /*
1297 * enqueue_abort: rollback.
1298 */
1299 int
1300 virtio_enqueue_abort(struct virtio_softc *sc, struct virtqueue *vq, int slot)
1301 {
1302 struct vq_entry *qe = &vq->vq_entries[slot];
1303 struct vring_desc *vd;
1304 int s;
1305
1306 if (qe->qe_next < 0) {
1307 vq_free_entry(vq, qe);
1308 return 0;
1309 }
1310
1311 s = slot;
1312 vd = &vq->vq_desc[0];
1313 while (vd[s].flags & VRING_DESC_F_NEXT) {
1314 s = vd[s].next;
1315 vq_free_entry(vq, qe);
1316 qe = &vq->vq_entries[s];
1317 }
1318 vq_free_entry(vq, qe);
1319 return 0;
1320 }
1321
1322 /*
1323 * Dequeue a request.
1324 */
1325 /*
1326 * dequeue: dequeue a request from uring; dmamap_sync for uring is
1327 * already done in the interrupt handler.
1328 */
1329 int
1330 virtio_dequeue(struct virtio_softc *sc, struct virtqueue *vq,
1331 int *slotp, int *lenp)
1332 {
1333 uint16_t slot, usedidx;
1334 struct vq_entry *qe;
1335
1336 if (vq->vq_used_idx == vq->vq_used->idx)
1337 return ENOENT;
1338 mutex_enter(&vq->vq_uring_lock);
1339 usedidx = vq->vq_used_idx++;
1340 mutex_exit(&vq->vq_uring_lock);
1341 usedidx %= vq->vq_num;
1342 slot = vq->vq_used->ring[usedidx].id;
1343 qe = &vq->vq_entries[slot];
1344
1345 if (qe->qe_indirect)
1346 vq_sync_indirect(sc, vq, slot, BUS_DMASYNC_POSTWRITE);
1347
1348 if (slotp)
1349 *slotp = slot;
1350 if (lenp)
1351 *lenp = vq->vq_used->ring[usedidx].len;
1352
1353 return 0;
1354 }
1355
1356 /*
1357 * dequeue_commit: complete dequeue; the slot is recycled for future use.
1358 * if you forget to call this the slot will be leaked.
1359 */
1360 int
1361 virtio_dequeue_commit(struct virtio_softc *sc, struct virtqueue *vq, int slot)
1362 {
1363 struct vq_entry *qe = &vq->vq_entries[slot];
1364 struct vring_desc *vd = &vq->vq_desc[0];
1365 int s = slot;
1366
1367 while (vd[s].flags & VRING_DESC_F_NEXT) {
1368 s = vd[s].next;
1369 vq_free_entry(vq, qe);
1370 qe = &vq->vq_entries[s];
1371 }
1372 vq_free_entry(vq, qe);
1373
1374 return 0;
1375 }
1376
1377 /*
1378 * Attach a child, fill all the members.
1379 */
1380 void
1381 virtio_child_attach_start(struct virtio_softc *sc, device_t child, int ipl,
1382 struct virtqueue *vqs,
1383 virtio_callback config_change,
1384 virtio_callback intr_hand,
1385 int req_flags, int req_features, const char *feat_bits)
1386 {
1387 char buf[256];
1388 int features;
1389
1390 sc->sc_child = child;
1391 sc->sc_ipl = ipl;
1392 sc->sc_vqs = vqs;
1393 sc->sc_config_change = config_change;
1394 sc->sc_intrhand = intr_hand;
1395 sc->sc_flags = req_flags;
1396
1397 features = virtio_negotiate_features(sc, req_features);
1398 snprintb(buf, sizeof(buf), feat_bits, features);
1399 aprint_normal(": Features: %s\n", buf);
1400 aprint_naive("\n");
1401 }
1402
1403 int
1404 virtio_child_attach_finish(struct virtio_softc *sc)
1405 {
1406 int r;
1407
1408 r = virtio_setup_interrupts(sc);
1409 if (r != 0) {
1410 aprint_error_dev(sc->sc_dev, "failed to setup interrupts\n");
1411 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
1412 return 1;
1413 }
1414
1415 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER_OK);
1416
1417 return 0;
1418 }
1419
1420 void
1421 virtio_child_detach(struct virtio_softc *sc)
1422 {
1423 sc->sc_child = NULL;
1424 sc->sc_vqs = NULL;
1425
1426 virtio_device_reset(sc);
1427
1428 virtio_free_interrupts(sc);
1429 }
1430
1431 void
1432 virtio_child_attach_failed(struct virtio_softc *sc)
1433 {
1434 virtio_child_detach(sc);
1435
1436 virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
1437
1438 sc->sc_child = VIRTIO_CHILD_FAILED;
1439 }
1440
1441 bus_dma_tag_t
1442 virtio_dmat(struct virtio_softc *sc)
1443 {
1444 return sc->sc_dmat;
1445 }
1446
1447 device_t
1448 virtio_child(struct virtio_softc *sc)
1449 {
1450 return sc->sc_child;
1451 }
1452
1453 int
1454 virtio_intrhand(struct virtio_softc *sc)
1455 {
1456 return (sc->sc_intrhand)(sc);
1457 }
1458
1459 uint32_t
1460 virtio_features(struct virtio_softc *sc)
1461 {
1462 return sc->sc_features;
1463 }
1464
1465 MODULE(MODULE_CLASS_DRIVER, virtio, "pci");
1466
1467 #ifdef _MODULE
1468 #include "ioconf.c"
1469 #endif
1470
1471 static int
1472 virtio_modcmd(modcmd_t cmd, void *opaque)
1473 {
1474 int error = 0;
1475
1476 #ifdef _MODULE
1477 switch (cmd) {
1478 case MODULE_CMD_INIT:
1479 error = config_init_component(cfdriver_ioconf_virtio,
1480 cfattach_ioconf_virtio, cfdata_ioconf_virtio);
1481 break;
1482 case MODULE_CMD_FINI:
1483 error = config_fini_component(cfdriver_ioconf_virtio,
1484 cfattach_ioconf_virtio, cfdata_ioconf_virtio);
1485 break;
1486 default:
1487 error = ENOTTY;
1488 break;
1489 }
1490 #endif
1491
1492 return error;
1493 }
1494