xref: /netbsd-src/sys/dev/pci/virtio_pci.c (revision 404ee5b9334f618040b6cdef96a0ff35a6fc4636)
1 /* $NetBSD: virtio_pci.c,v 1.7 2019/01/27 02:08:42 pgoyette 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_pci.c,v 1.7 2019/01/27 02:08:42 pgoyette Exp $");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kmem.h>
34 #include <sys/module.h>
35 #include <sys/interrupt.h>
36 
37 #include <sys/device.h>
38 
39 #include <dev/pci/pcidevs.h>
40 #include <dev/pci/pcireg.h>
41 #include <dev/pci/pcivar.h>
42 
43 #define VIRTIO_PRIVATE
44 
45 #include <dev/pci/virtioreg.h> /* XXX: move to non-pci */
46 #include <dev/pci/virtiovar.h> /* XXX: move to non-pci */
47 
48 static int	virtio_pci_match(device_t, cfdata_t, void *);
49 static void	virtio_pci_attach(device_t, device_t, void *);
50 static int	virtio_pci_rescan(device_t, const char *, const int *);
51 static int	virtio_pci_detach(device_t, int);
52 
53 struct virtio_pci_softc {
54 	struct virtio_softc	sc_sc;
55 	bus_space_tag_t		sc_iot;
56 	bus_space_handle_t	sc_ioh;
57 	bus_size_t		sc_iosize;
58 	struct pci_attach_args	sc_pa;
59 	pci_intr_handle_t	*sc_ihp;
60 	void			**sc_ihs;
61 	int			sc_ihs_num;
62 	int			sc_config_offset;
63 };
64 
65 static void	virtio_pci_kick(struct virtio_softc *, uint16_t);
66 static uint8_t	virtio_pci_read_device_config_1(struct virtio_softc *, int);
67 static uint16_t	virtio_pci_read_device_config_2(struct virtio_softc *, int);
68 static uint32_t	virtio_pci_read_device_config_4(struct virtio_softc *, int);
69 static uint64_t	virtio_pci_read_device_config_8(struct virtio_softc *, int);
70 static void 	virtio_pci_write_device_config_1(struct virtio_softc *, int, uint8_t);
71 static void	virtio_pci_write_device_config_2(struct virtio_softc *, int, uint16_t);
72 static void	virtio_pci_write_device_config_4(struct virtio_softc *, int, uint32_t);
73 static void	virtio_pci_write_device_config_8(struct virtio_softc *, int, uint64_t);
74 static uint16_t	virtio_pci_read_queue_size(struct virtio_softc *, uint16_t);
75 static void	virtio_pci_setup_queue(struct virtio_softc *, uint16_t, uint32_t);
76 static void	virtio_pci_set_status(struct virtio_softc *, int);
77 static uint32_t	virtio_pci_negotiate_features(struct virtio_softc *, uint32_t);
78 static int	virtio_pci_setup_interrupts(struct virtio_softc *);
79 static void	virtio_pci_free_interrupts(struct virtio_softc *);
80 
81 static int	virtio_pci_intr(void *arg);
82 static int	virtio_pci_msix_queue_intr(void *);
83 static int	virtio_pci_msix_vq_intr(void *);
84 static int	virtio_pci_msix_config_intr(void *);
85 static int	virtio_pci_setup_msix_vectors(struct virtio_softc *);
86 static int	virtio_pci_setup_msix_interrupts(struct virtio_softc *,
87 		    struct pci_attach_args *);
88 static int	virtio_pci_setup_intx_interrupt(struct virtio_softc *,
89 		    struct pci_attach_args *);
90 
91 #define VIRTIO_MSIX_CONFIG_VECTOR_INDEX	0
92 #define VIRTIO_MSIX_QUEUE_VECTOR_INDEX	1
93 
94 /* we use the legacy virtio spec, so the PCI registers are host native
95  * byte order, not PCI (i.e. LE) byte order */
96 #if BYTE_ORDER == BIG_ENDIAN
97 #define REG_HI_OFF      0
98 #define REG_LO_OFF      4
99 #ifndef __BUS_SPACE_HAS_STREAM_METHODS
100 #define bus_space_read_stream_1 bus_space_read_1
101 #define bus_space_write_stream_1 bus_space_write_1
102 static inline uint16_t
103 bus_space_read_stream_2(bus_space_tag_t t, bus_space_handle_t h,
104     bus_size_t o)
105 {
106 	return le16toh(bus_space_read_2(t, h, o));
107 }
108 static inline void
109 bus_space_write_stream_2(bus_space_tag_t t, bus_space_handle_t h,
110     bus_size_t o, uint16_t v)
111 {
112 	bus_space_write_2(t, h, o, htole16(v));
113 }
114 static inline uint32_t
115 bus_space_read_stream_4(bus_space_tag_t t, bus_space_handle_t h,
116     bus_size_t o)
117 {
118 	return le32toh(bus_space_read_4(t, h, o));
119 }
120 static inline void
121 bus_space_write_stream_4(bus_space_tag_t t, bus_space_handle_t h,
122     bus_size_t o, uint32_t v)
123 {
124 	bus_space_write_4(t, h, o, htole32(v));
125 }
126 #endif
127 #else
128 #define REG_HI_OFF	4
129 #define REG_LO_OFF	0
130 #ifndef __BUS_SPACE_HAS_STREAM_METHODS
131 #define bus_space_read_stream_1 bus_space_read_1
132 #define bus_space_read_stream_2 bus_space_read_2
133 #define bus_space_read_stream_4 bus_space_read_4
134 #define bus_space_write_stream_1 bus_space_write_1
135 #define bus_space_write_stream_2 bus_space_write_2
136 #define bus_space_write_stream_4 bus_space_write_4
137 #endif
138 #endif
139 
140 
141 static const char *virtio_device_name[] = {
142 	"Unknown (0)",			/* 0 */
143 	"Network",			/* 1 */
144 	"Block",			/* 2 */
145 	"Console",			/* 3 */
146 	"Entropy",			/* 4 */
147 	"Memory Balloon",		/* 5 */
148 	"I/O Memory",			/* 6 */
149 	"Remote Processor Messaging",	/* 7 */
150 	"SCSI",				/* 8 */
151 	"9P Transport",			/* 9 */
152 	"mac80211 wlan",		/* 10 */
153 };
154 #define NDEVNAMES	__arraycount(virtio_device_name)
155 
156 CFATTACH_DECL3_NEW(virtio_pci, sizeof(struct virtio_pci_softc),
157     virtio_pci_match, virtio_pci_attach, virtio_pci_detach, NULL,
158     virtio_pci_rescan, NULL, DVF_DETACH_SHUTDOWN);
159 
160 static const struct virtio_ops virtio_pci_ops = {
161 	.kick = virtio_pci_kick,
162 	.read_dev_cfg_1 = virtio_pci_read_device_config_1,
163 	.read_dev_cfg_2 = virtio_pci_read_device_config_2,
164 	.read_dev_cfg_4 = virtio_pci_read_device_config_4,
165 	.read_dev_cfg_8 = virtio_pci_read_device_config_8,
166 	.write_dev_cfg_1 = virtio_pci_write_device_config_1,
167 	.write_dev_cfg_2 = virtio_pci_write_device_config_2,
168 	.write_dev_cfg_4 = virtio_pci_write_device_config_4,
169 	.write_dev_cfg_8 = virtio_pci_write_device_config_8,
170 	.read_queue_size = virtio_pci_read_queue_size,
171 	.setup_queue = virtio_pci_setup_queue,
172 	.set_status = virtio_pci_set_status,
173 	.neg_features = virtio_pci_negotiate_features,
174 	.setup_interrupts = virtio_pci_setup_interrupts,
175 	.free_interrupts = virtio_pci_free_interrupts,
176 };
177 
178 static int
179 virtio_pci_match(device_t parent, cfdata_t match, void *aux)
180 {
181 	struct pci_attach_args *pa;
182 
183 	pa = (struct pci_attach_args *)aux;
184 	switch (PCI_VENDOR(pa->pa_id)) {
185 	case PCI_VENDOR_QUMRANET:
186 		if ((PCI_PRODUCT_QUMRANET_VIRTIO_1000 <=
187 		     PCI_PRODUCT(pa->pa_id)) &&
188 		    (PCI_PRODUCT(pa->pa_id) <=
189 		     PCI_PRODUCT_QUMRANET_VIRTIO_103F))
190 			return 1;
191 		break;
192 	}
193 
194 	return 0;
195 }
196 
197 static void
198 virtio_pci_attach(device_t parent, device_t self, void *aux)
199 {
200 	struct virtio_pci_softc * const psc = device_private(self);
201 	struct virtio_softc * const sc = &psc->sc_sc;
202 	struct pci_attach_args *pa = (struct pci_attach_args *)aux;
203 	pci_chipset_tag_t pc = pa->pa_pc;
204 	pcitag_t tag = pa->pa_tag;
205 	int revision;
206 	pcireg_t id;
207 	pcireg_t csr;
208 
209 	revision = PCI_REVISION(pa->pa_class);
210 	if (revision != 0) {
211 		aprint_normal(": unknown revision 0x%02x; giving up\n",
212 			      revision);
213 		return;
214 	}
215 	aprint_normal("\n");
216 	aprint_naive("\n");
217 
218 	/* subsystem ID shows what I am */
219 	id = pci_conf_read(pc, tag, PCI_SUBSYS_ID_REG);
220 	aprint_normal_dev(self, "Virtio %s Device (rev. 0x%02x)\n",
221 			  (PCI_SUBSYS_ID(id) < NDEVNAMES?
222 			   virtio_device_name[PCI_SUBSYS_ID(id)] : "Unknown"),
223 			  revision);
224 
225 	csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
226 	csr |= PCI_COMMAND_MASTER_ENABLE | PCI_COMMAND_IO_ENABLE;
227 	pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
228 
229 	sc->sc_dev = self;
230 	sc->sc_ops = &virtio_pci_ops;
231 	psc->sc_pa = *pa;
232 	psc->sc_iot = pa->pa_iot;
233 	if (pci_dma64_available(pa))
234 		sc->sc_dmat = pa->pa_dmat64;
235 	else
236 		sc->sc_dmat = pa->pa_dmat;
237 	psc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
238 
239 	if (pci_mapreg_map(pa, PCI_MAPREG_START, PCI_MAPREG_TYPE_IO, 0,
240 			   &psc->sc_iot, &psc->sc_ioh, NULL, &psc->sc_iosize)) {
241 		aprint_error_dev(self, "can't map i/o space\n");
242 		return;
243 	}
244 
245 	virtio_device_reset(sc);
246 	virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_ACK);
247 	virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER);
248 
249 	sc->sc_childdevid = PCI_SUBSYS_ID(id);
250 	sc->sc_child = NULL;
251 	virtio_pci_rescan(self, "virtio", 0);
252 	return;
253 }
254 
255 /* ARGSUSED */
256 static int
257 virtio_pci_rescan(device_t self, const char *attr, const int *scan_flags)
258 {
259 	struct virtio_pci_softc * const psc = device_private(self);
260 	struct virtio_softc * const sc = &psc->sc_sc;
261 	struct virtio_attach_args va;
262 
263 	if (sc->sc_child)	/* Child already attached? */
264 		return 0;
265 
266 	memset(&va, 0, sizeof(va));
267 	va.sc_childdevid = sc->sc_childdevid;
268 
269 	config_found_ia(self, attr, &va, NULL);
270 
271 	if (sc->sc_child == NULL) {
272 		aprint_error_dev(self,
273 				 "no matching child driver; not configured\n");
274 		return 0;
275 	}
276 
277 	if (sc->sc_child == VIRTIO_CHILD_FAILED) {
278 		aprint_error_dev(self,
279 				 "virtio configuration failed\n");
280 		return 0;
281 	}
282 
283 	/*
284 	 * Make sure child drivers initialize interrupts via call
285 	 * to virtio_child_attach_finish().
286 	 */
287 	KASSERT(psc->sc_ihs_num != 0);
288 
289 	return 0;
290 }
291 
292 
293 static int
294 virtio_pci_detach(device_t self, int flags)
295 {
296 	struct virtio_pci_softc * const psc = device_private(self);
297 	struct virtio_softc * const sc = &psc->sc_sc;
298 	int r;
299 
300 	if (sc->sc_child != NULL) {
301 		r = config_detach(sc->sc_child, flags);
302 		if (r)
303 			return r;
304 	}
305 
306 	/* Check that child detached properly */
307 	KASSERT(sc->sc_child == NULL);
308 	KASSERT(sc->sc_vqs == NULL);
309 	KASSERT(psc->sc_ihs_num == 0);
310 
311 	if (psc->sc_iosize)
312 		bus_space_unmap(psc->sc_iot, psc->sc_ioh, psc->sc_iosize);
313 	psc->sc_iosize = 0;
314 
315 	return 0;
316 }
317 
318 static void
319 virtio_pci_kick(struct virtio_softc *sc, uint16_t idx)
320 {
321 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
322 
323 	bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh,
324 	    VIRTIO_CONFIG_QUEUE_NOTIFY, idx);
325 }
326 
327 static uint8_t
328 virtio_pci_read_device_config_1(struct virtio_softc *sc, int index)
329 {
330 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
331 	return bus_space_read_stream_1(psc->sc_iot, psc->sc_ioh,
332 	    psc->sc_config_offset + index);
333 }
334 
335 static uint16_t
336 virtio_pci_read_device_config_2(struct virtio_softc *sc, int index)
337 {
338 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
339 	return bus_space_read_stream_2(psc->sc_iot, psc->sc_ioh,
340 	    psc->sc_config_offset + index);
341 }
342 
343 static uint32_t
344 virtio_pci_read_device_config_4(struct virtio_softc *sc, int index)
345 {
346 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
347 	return bus_space_read_stream_4(psc->sc_iot, psc->sc_ioh,
348 	    psc->sc_config_offset + index);
349 }
350 
351 static uint64_t
352 virtio_pci_read_device_config_8(struct virtio_softc *sc, int index)
353 {
354 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
355 	uint64_t r;
356 
357 	r = bus_space_read_stream_4(psc->sc_iot, psc->sc_ioh,
358 	    psc->sc_config_offset + index + REG_HI_OFF);
359 	r <<= 32;
360 	r |= bus_space_read_stream_4(psc->sc_iot, psc->sc_ioh,
361 	    psc->sc_config_offset + index + REG_LO_OFF);
362 
363 	return r;
364 }
365 
366 static void
367 virtio_pci_write_device_config_1(struct virtio_softc *sc, int index,
368     uint8_t value)
369 {
370 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
371 
372 	bus_space_write_stream_1(psc->sc_iot, psc->sc_ioh,
373 	    psc->sc_config_offset + index, value);
374 }
375 
376 static void
377 virtio_pci_write_device_config_2(struct virtio_softc *sc, int index,
378     uint16_t value)
379 {
380 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
381 
382 	bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh,
383 	    psc->sc_config_offset + index, value);
384 }
385 
386 static void
387 virtio_pci_write_device_config_4(struct virtio_softc *sc, int index,
388     uint32_t value)
389 {
390 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
391 
392 	bus_space_write_stream_4(psc->sc_iot, psc->sc_ioh,
393 	    psc->sc_config_offset + index, value);
394 }
395 
396 static void
397 virtio_pci_write_device_config_8(struct virtio_softc *sc, int index,
398     uint64_t value)
399 {
400 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
401 
402 	bus_space_write_stream_4(psc->sc_iot, psc->sc_ioh,
403 	    psc->sc_config_offset + index + REG_LO_OFF,
404 	    value & 0xffffffff);
405 	bus_space_write_stream_4(psc->sc_iot, psc->sc_ioh,
406 	    psc->sc_config_offset + index + REG_HI_OFF,
407 	    value >> 32);
408 }
409 
410 static uint16_t
411 virtio_pci_read_queue_size(struct virtio_softc *sc, uint16_t idx)
412 {
413 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
414 
415 	bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh,
416 	    VIRTIO_CONFIG_QUEUE_SELECT, idx);
417 	return bus_space_read_stream_2(psc->sc_iot, psc->sc_ioh,
418 	    VIRTIO_CONFIG_QUEUE_SIZE);
419 }
420 
421 static void
422 virtio_pci_setup_queue(struct virtio_softc *sc, uint16_t idx, uint32_t addr)
423 {
424 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
425 
426 	bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh,
427 	    VIRTIO_CONFIG_QUEUE_SELECT, idx);
428 	bus_space_write_stream_4(psc->sc_iot, psc->sc_ioh,
429 	    VIRTIO_CONFIG_QUEUE_ADDRESS, addr);
430 
431 	if (psc->sc_ihs_num > 1) {
432 		int vec = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
433 		if (sc->sc_child_mq)
434 			vec += idx;
435 		bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh,
436 		    VIRTIO_CONFIG_MSI_QUEUE_VECTOR, vec);
437 	}
438 }
439 
440 static void
441 virtio_pci_set_status(struct virtio_softc *sc, int status)
442 {
443 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
444 	int old = 0;
445 
446 	if (status != 0) {
447 	    old = bus_space_read_stream_1(psc->sc_iot, psc->sc_ioh,
448 		VIRTIO_CONFIG_DEVICE_STATUS);
449 	}
450 	bus_space_write_stream_1(psc->sc_iot, psc->sc_ioh,
451 	    VIRTIO_CONFIG_DEVICE_STATUS, status|old);
452 }
453 
454 static uint32_t
455 virtio_pci_negotiate_features(struct virtio_softc *sc, uint32_t guest_features)
456 {
457 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
458 	uint32_t r;
459 
460 	r = bus_space_read_stream_4(psc->sc_iot, psc->sc_ioh,
461 	    VIRTIO_CONFIG_DEVICE_FEATURES);
462 	r &= guest_features;
463 	bus_space_write_stream_4(psc->sc_iot, psc->sc_ioh,
464 	    VIRTIO_CONFIG_GUEST_FEATURES, r);
465 
466 	return r;
467 }
468 
469 
470 static int
471 virtio_pci_setup_msix_vectors(struct virtio_softc *sc)
472 {
473 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
474 	int offset, vector, ret, qid;
475 
476 	offset = VIRTIO_CONFIG_MSI_CONFIG_VECTOR;
477 	vector = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
478 
479 	bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh, offset, vector);
480 	ret = bus_space_read_stream_2(psc->sc_iot, psc->sc_ioh, offset);
481 	aprint_debug_dev(sc->sc_dev, "expected=%d, actual=%d\n",
482 	    vector, ret);
483 	if (ret != vector)
484 		return -1;
485 
486 	for (qid = 0; qid < sc->sc_nvqs; qid++) {
487 		offset = VIRTIO_CONFIG_QUEUE_SELECT;
488 		bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh, offset, qid);
489 
490 		offset = VIRTIO_CONFIG_MSI_QUEUE_VECTOR;
491 		vector = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
492 
493 		if (sc->sc_child_mq)
494 			vector += qid;
495 
496 		bus_space_write_stream_2(psc->sc_iot, psc->sc_ioh, offset, vector);
497 		ret = bus_space_read_stream_2(psc->sc_iot, psc->sc_ioh, offset);
498 		aprint_debug_dev(sc->sc_dev, "expected=%d, actual=%d\n",
499 		    vector, ret);
500 		if (ret != vector)
501 			return -1;
502 	}
503 
504 	return 0;
505 }
506 
507 static int
508 virtio_pci_setup_msix_interrupts(struct virtio_softc *sc,
509     struct pci_attach_args *pa)
510 {
511 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
512 	device_t self = sc->sc_dev;
513 	pci_chipset_tag_t pc = pa->pa_pc;
514 	char intrbuf[PCI_INTRSTR_LEN];
515 	char intr_xname[INTRDEVNAMEBUF];
516 	char const *intrstr;
517 	int idx, qid, n;
518 
519 	idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
520 	if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
521 		pci_intr_setattr(pc, &psc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
522 
523 	snprintf(intr_xname, sizeof(intr_xname), "%s config",
524 	    device_xname(sc->sc_dev));
525 
526 	psc->sc_ihs[idx] = pci_intr_establish_xname(pc, psc->sc_ihp[idx],
527 	    sc->sc_ipl, virtio_pci_msix_config_intr, sc, intr_xname);
528 	if (psc->sc_ihs[idx] == NULL) {
529 		aprint_error_dev(self, "couldn't establish MSI-X for config\n");
530 		goto error;
531 	}
532 
533 	idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
534 	if (sc->sc_child_mq) {
535 		for (qid = 0; qid < sc->sc_nvqs; qid++) {
536 			n = idx + qid;
537 
538 			snprintf(intr_xname, sizeof(intr_xname), "%s vq#%d",
539 			    device_xname(sc->sc_dev), qid);
540 
541 			if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE) {
542 				pci_intr_setattr(pc, &psc->sc_ihp[n],
543 				    PCI_INTR_MPSAFE, true);
544 			}
545 
546 			psc->sc_ihs[n] = pci_intr_establish_xname(pc, psc->sc_ihp[n],
547 			    sc->sc_ipl, virtio_pci_msix_vq_intr, &sc->sc_vqs[qid],
548 			    intr_xname);
549 			if (psc->sc_ihs[n] == NULL) {
550 				aprint_error_dev(self, "couldn't establish MSI-X for a vq\n");
551 				goto error;
552 			}
553 		}
554 	} else {
555 		if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
556 			pci_intr_setattr(pc, &psc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
557 
558 		snprintf(intr_xname, sizeof(intr_xname), "%s queues",
559 		    device_xname(sc->sc_dev));
560 		psc->sc_ihs[idx] = pci_intr_establish_xname(pc, psc->sc_ihp[idx],
561 		    sc->sc_ipl, virtio_pci_msix_queue_intr, sc, intr_xname);
562 		if (psc->sc_ihs[idx] == NULL) {
563 			aprint_error_dev(self, "couldn't establish MSI-X for queues\n");
564 			goto error;
565 		}
566 	}
567 
568 	if (virtio_pci_setup_msix_vectors(sc) != 0) {
569 		aprint_error_dev(self, "couldn't setup MSI-X vectors\n");
570 		goto error;
571 	}
572 
573 	idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
574 	intrstr = pci_intr_string(pc, psc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
575 	aprint_normal_dev(self, "config interrupting at %s\n", intrstr);
576 	idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
577 	if (sc->sc_child_mq) {
578 		kcpuset_t *affinity;
579 		int affinity_to, r;
580 
581 		kcpuset_create(&affinity, false);
582 
583 		for (qid = 0; qid < sc->sc_nvqs; qid++) {
584 			n = idx + qid;
585 			affinity_to = (qid / 2) % ncpu;
586 
587 			intrstr = pci_intr_string(pc, psc->sc_ihp[n],
588 			    intrbuf, sizeof(intrbuf));
589 
590 			kcpuset_zero(affinity);
591 			kcpuset_set(affinity, affinity_to);
592 			r = interrupt_distribute(psc->sc_ihs[n], affinity, NULL);
593 			if (r == 0) {
594 				aprint_normal_dev(self,
595 				    "for vq #%d interrupting at %s affinity to %u\n",
596 				    qid, intrstr, affinity_to);
597 			} else {
598 				aprint_normal_dev(self,
599 				    "for vq #%d interrupting at %s\n",
600 				    qid, intrstr);
601 			}
602 		}
603 
604 		kcpuset_destroy(affinity);
605 	} else {
606 		intrstr = pci_intr_string(pc, psc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
607 		aprint_normal_dev(self, "queues interrupting at %s\n", intrstr);
608 	}
609 
610 	return 0;
611 
612 error:
613 	idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
614 	if (psc->sc_ihs[idx] != NULL)
615 		pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[idx]);
616 	idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
617 	if (sc->sc_child_mq) {
618 		for (qid = 0; qid < sc->sc_nvqs; qid++) {
619 			n = idx + qid;
620 			if (psc->sc_ihs[n] == NULL)
621 				continue;
622 			pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[n]);
623 		}
624 
625 	} else {
626 		if (psc->sc_ihs[idx] != NULL)
627 			pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[idx]);
628 	}
629 
630 	return -1;
631 }
632 
633 static int
634 virtio_pci_setup_intx_interrupt(struct virtio_softc *sc,
635     struct pci_attach_args *pa)
636 {
637 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
638 	device_t self = sc->sc_dev;
639 	pci_chipset_tag_t pc = pa->pa_pc;
640 	char intrbuf[PCI_INTRSTR_LEN];
641 	char const *intrstr;
642 
643 	if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
644 		pci_intr_setattr(pc, &psc->sc_ihp[0], PCI_INTR_MPSAFE, true);
645 
646 	psc->sc_ihs[0] = pci_intr_establish_xname(pc, psc->sc_ihp[0],
647 	    sc->sc_ipl, virtio_pci_intr, sc, device_xname(sc->sc_dev));
648 	if (psc->sc_ihs[0] == NULL) {
649 		aprint_error_dev(self, "couldn't establish INTx\n");
650 		return -1;
651 	}
652 
653 	intrstr = pci_intr_string(pc, psc->sc_ihp[0], intrbuf, sizeof(intrbuf));
654 	aprint_normal_dev(self, "interrupting at %s\n", intrstr);
655 
656 	return 0;
657 }
658 
659 static int
660 virtio_pci_setup_interrupts(struct virtio_softc *sc)
661 {
662 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
663 	device_t self = sc->sc_dev;
664 	pci_chipset_tag_t pc = psc->sc_pa.pa_pc;
665 	int error;
666 	int nmsix;
667 	int counts[PCI_INTR_TYPE_SIZE];
668 	pci_intr_type_t max_type;
669 
670 	nmsix = pci_msix_count(psc->sc_pa.pa_pc, psc->sc_pa.pa_tag);
671 	aprint_debug_dev(self, "pci_msix_count=%d\n", nmsix);
672 
673 	/* We need at least two: one for config and the other for queues */
674 	if ((sc->sc_flags & VIRTIO_F_PCI_INTR_MSIX) == 0 || nmsix < 2) {
675 		/* Try INTx only */
676 		max_type = PCI_INTR_TYPE_INTX;
677 		counts[PCI_INTR_TYPE_INTX] = 1;
678 	} else {
679 		/* Try MSI-X first and INTx second */
680 		if (sc->sc_child_mq &&
681 		    sc->sc_nvqs > (nmsix - VIRTIO_MSIX_QUEUE_VECTOR_INDEX)) {
682 			nmsix = 2;
683 			sc->sc_child_mq = false;
684 		}
685 
686 		max_type = PCI_INTR_TYPE_MSIX;
687 		counts[PCI_INTR_TYPE_MSIX] = nmsix;
688 		counts[PCI_INTR_TYPE_MSI] = 0;
689 		counts[PCI_INTR_TYPE_INTX] = 1;
690 	}
691 
692 retry:
693 	error = pci_intr_alloc(&psc->sc_pa, &psc->sc_ihp, counts, max_type);
694 	if (error != 0) {
695 		aprint_error_dev(self, "couldn't map interrupt\n");
696 		return -1;
697 	}
698 
699 	if (pci_intr_type(pc, psc->sc_ihp[0]) == PCI_INTR_TYPE_MSIX) {
700 		psc->sc_ihs = kmem_alloc(sizeof(*psc->sc_ihs) * nmsix,
701 		    KM_SLEEP);
702 
703 		error = virtio_pci_setup_msix_interrupts(sc, &psc->sc_pa);
704 		if (error != 0) {
705 			kmem_free(psc->sc_ihs, sizeof(*psc->sc_ihs) * nmsix);
706 			pci_intr_release(pc, psc->sc_ihp, nmsix);
707 
708 			/* Retry INTx */
709 			max_type = PCI_INTR_TYPE_INTX;
710 			counts[PCI_INTR_TYPE_INTX] = 1;
711 			goto retry;
712 		}
713 
714 		psc->sc_ihs_num = nmsix;
715 		psc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_MSI;
716 	} else if (pci_intr_type(pc, psc->sc_ihp[0]) == PCI_INTR_TYPE_INTX) {
717 		psc->sc_ihs = kmem_alloc(sizeof(*psc->sc_ihs) * 1,
718 		    KM_SLEEP);
719 
720 		error = virtio_pci_setup_intx_interrupt(sc, &psc->sc_pa);
721 		if (error != 0) {
722 			kmem_free(psc->sc_ihs, sizeof(*psc->sc_ihs) * 1);
723 			pci_intr_release(pc, psc->sc_ihp, 1);
724 			return -1;
725 		}
726 
727 		psc->sc_ihs_num = 1;
728 		psc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
729 	}
730 
731 	return 0;
732 }
733 
734 static void
735 virtio_pci_free_interrupts(struct virtio_softc *sc)
736 {
737 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
738 
739 	for (int i = 0; i < psc->sc_ihs_num; i++) {
740 		if (psc->sc_ihs[i] == NULL)
741 			continue;
742 		pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[i]);
743 		psc->sc_ihs[i] = NULL;
744 	}
745 
746 	if (psc->sc_ihs_num > 0)
747 		pci_intr_release(psc->sc_pa.pa_pc, psc->sc_ihp, psc->sc_ihs_num);
748 
749 	if (psc->sc_ihs != NULL) {
750 		kmem_free(psc->sc_ihs, sizeof(*psc->sc_ihs) * psc->sc_ihs_num);
751 		psc->sc_ihs = NULL;
752 	}
753 	psc->sc_ihs_num = 0;
754 }
755 
756 /*
757  * Interrupt handler.
758  */
759 static int
760 virtio_pci_intr(void *arg)
761 {
762 	struct virtio_softc *sc = arg;
763 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
764 	int isr, r = 0;
765 
766 	/* check and ack the interrupt */
767 	isr = bus_space_read_stream_1(psc->sc_iot, psc->sc_ioh,
768 			       VIRTIO_CONFIG_ISR_STATUS);
769 	if (isr == 0)
770 		return 0;
771 	if ((isr & VIRTIO_CONFIG_ISR_CONFIG_CHANGE) &&
772 	    (sc->sc_config_change != NULL))
773 		r = (sc->sc_config_change)(sc);
774 	if (sc->sc_intrhand != NULL) {
775 		if (sc->sc_soft_ih != NULL)
776 			softint_schedule(sc->sc_soft_ih);
777 		else
778 			r |= (sc->sc_intrhand)(sc);
779 	}
780 
781 	return r;
782 }
783 
784 static int
785 virtio_pci_msix_queue_intr(void *arg)
786 {
787 	struct virtio_softc *sc = arg;
788 	int r = 0;
789 
790 	if (sc->sc_intrhand != NULL) {
791 		if (sc->sc_soft_ih != NULL)
792 			softint_schedule(sc->sc_soft_ih);
793 		else
794 			r |= (sc->sc_intrhand)(sc);
795 	}
796 
797 	return r;
798 }
799 
800 static int
801 virtio_pci_msix_vq_intr(void *arg)
802 {
803 	struct virtqueue *vq = arg;
804 	int r = 0;
805 
806 	if (vq->vq_intrhand != NULL) {
807 		if (vq->vq_soft_ih)
808 			softint_schedule(vq->vq_soft_ih);
809 		else
810 			r |= vq->vq_intrhand(vq);
811 	}
812 
813 	return r;
814 }
815 
816 static int
817 virtio_pci_msix_config_intr(void *arg)
818 {
819 	struct virtio_softc *sc = arg;
820 	int r = 0;
821 
822 	if (sc->sc_config_change != NULL)
823 		r = (sc->sc_config_change)(sc);
824 	return r;
825 }
826 
827 MODULE(MODULE_CLASS_DRIVER, virtio_pci, "pci,virtio");
828 
829 #ifdef _MODULE
830 #include "ioconf.c"
831 #endif
832 
833 static int
834 virtio_pci_modcmd(modcmd_t cmd, void *opaque)
835 {
836 	int error = 0;
837 
838 #ifdef _MODULE
839 	switch (cmd) {
840 	case MODULE_CMD_INIT:
841 		error = config_init_component(cfdriver_ioconf_virtio_pci,
842 		    cfattach_ioconf_virtio_pci, cfdata_ioconf_virtio_pci);
843 		break;
844 	case MODULE_CMD_FINI:
845 		error = config_fini_component(cfdriver_ioconf_virtio_pci,
846 		    cfattach_ioconf_virtio_pci, cfdata_ioconf_virtio_pci);
847 		break;
848 	default:
849 		error = ENOTTY;
850 		break;
851 	}
852 #endif
853 
854 	return error;
855 }
856