xref: /netbsd-src/sys/dev/pci/virtio_pci.c (revision 3f351f34c6d827cf017cdcff3543f6ec0c88b420)
1 /* $NetBSD: virtio_pci.c,v 1.44 2023/11/19 19:49:44 thorpej Exp $ */
2 
3 /*
4  * Copyright (c) 2020 The NetBSD Foundation, Inc.
5  * Copyright (c) 2012 Stefan Fritsch.
6  * Copyright (c) 2010 Minoura Makoto.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __KERNEL_RCSID(0, "$NetBSD: virtio_pci.c,v 1.44 2023/11/19 19:49:44 thorpej Exp $");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kmem.h>
36 #include <sys/module.h>
37 #include <sys/endian.h>
38 #include <sys/interrupt.h>
39 #include <sys/syslog.h>
40 
41 #include <sys/device.h>
42 
43 #include <dev/pci/pcidevs.h>
44 #include <dev/pci/pcireg.h>
45 #include <dev/pci/pcivar.h>
46 
47 #include <dev/pci/virtioreg.h> /* XXX: move to non-pci */
48 #include <dev/pci/virtio_pcireg.h>
49 
50 #define VIRTIO_PRIVATE
51 #include <dev/pci/virtiovar.h> /* XXX: move to non-pci */
52 
53 #if defined(__alpha__) || defined(__sparc64__)
54 /*
55  * XXX VIRTIO_F_ACCESS_PLATFORM is required for standard PCI DMA
56  * XXX to work on these platforms, at least by Qemu.
57  * XXX
58  * XXX Generalize this later.
59  */
60 #define	__NEED_VIRTIO_F_ACCESS_PLATFORM
61 #endif /* __alpha__ || __sparc64__ */
62 
63 #define VIRTIO_PCI_LOG(_sc, _use_log, _fmt, _args...)	\
64 do {							\
65 	if ((_use_log)) {				\
66 		log(LOG_DEBUG, "%s: " _fmt,		\
67 		    device_xname((_sc)->sc_dev),	\
68 		    ##_args);				\
69 	} else {					\
70 		aprint_error_dev((_sc)->sc_dev,		\
71 		    _fmt, ##_args);			\
72 	}						\
73 } while(0)
74 
75 static int	virtio_pci_match(device_t, cfdata_t, void *);
76 static void	virtio_pci_attach(device_t, device_t, void *);
77 static int	virtio_pci_rescan(device_t, const char *, const int *);
78 static int	virtio_pci_detach(device_t, int);
79 
80 
81 #define NMAPREG		((PCI_MAPREG_END - PCI_MAPREG_START) / \
82 				sizeof(pcireg_t))
83 struct virtio_pci_softc {
84 	struct virtio_softc	sc_sc;
85 	bool			sc_intr_pervq;
86 
87 	/* IO space */
88 	bus_space_tag_t		sc_iot;
89 	bus_space_handle_t	sc_ioh;
90 	bus_size_t		sc_iosize;
91 	bus_size_t		sc_mapped_iosize;
92 
93 	/* BARs */
94 	bus_space_tag_t		sc_bars_iot[NMAPREG];
95 	bus_space_handle_t	sc_bars_ioh[NMAPREG];
96 	bus_size_t		sc_bars_iosize[NMAPREG];
97 
98 	/* notify space */
99 	bus_space_tag_t		sc_notify_iot;
100 	bus_space_handle_t	sc_notify_ioh;
101 	bus_size_t		sc_notify_iosize;
102 	uint32_t		sc_notify_off_multiplier;
103 
104 	/* isr space */
105 	bus_space_tag_t		sc_isr_iot;
106 	bus_space_handle_t	sc_isr_ioh;
107 	bus_size_t		sc_isr_iosize;
108 
109 	/* generic */
110 	struct pci_attach_args	sc_pa;
111 	pci_intr_handle_t	*sc_ihp;
112 	void			**sc_ihs;
113 	int			sc_ihs_num;
114 	int			sc_devcfg_offset;	/* for 0.9 */
115 };
116 
117 static int	virtio_pci_attach_09(device_t, void *);
118 static void	virtio_pci_kick_09(struct virtio_softc *, uint16_t);
119 static uint16_t	virtio_pci_read_queue_size_09(struct virtio_softc *, uint16_t);
120 static void	virtio_pci_setup_queue_09(struct virtio_softc *, uint16_t, uint64_t);
121 static void	virtio_pci_set_status_09(struct virtio_softc *, int);
122 static void	virtio_pci_negotiate_features_09(struct virtio_softc *, uint64_t);
123 
124 static int	virtio_pci_attach_10(device_t, void *);
125 static void	virtio_pci_kick_10(struct virtio_softc *, uint16_t);
126 static uint16_t	virtio_pci_read_queue_size_10(struct virtio_softc *, uint16_t);
127 static void	virtio_pci_setup_queue_10(struct virtio_softc *, uint16_t, uint64_t);
128 static void	virtio_pci_set_status_10(struct virtio_softc *, int);
129 static void	virtio_pci_negotiate_features_10(struct virtio_softc *, uint64_t);
130 static int	virtio_pci_find_cap(struct virtio_pci_softc *psc, int cfg_type, void *buf, int buflen);
131 
132 static int	virtio_pci_alloc_interrupts(struct virtio_softc *);
133 static void	virtio_pci_free_interrupts(struct virtio_softc *);
134 static int	virtio_pci_adjust_config_region(struct virtio_pci_softc *psc);
135 static int	virtio_pci_intr(void *arg);
136 static int	virtio_pci_msix_queue_intr(void *);
137 static int	virtio_pci_msix_config_intr(void *);
138 static int	virtio_pci_setup_interrupts_09(struct virtio_softc *, int);
139 static int	virtio_pci_setup_interrupts_10(struct virtio_softc *, int);
140 static int	virtio_pci_establish_msix_interrupts(struct virtio_softc *,
141 		    struct pci_attach_args *);
142 static int	virtio_pci_establish_intx_interrupt(struct virtio_softc *,
143 		    struct pci_attach_args *);
144 static bool	virtio_pci_msix_enabled(struct virtio_pci_softc *);
145 
146 #define VIRTIO_MSIX_CONFIG_VECTOR_INDEX	0
147 #define VIRTIO_MSIX_QUEUE_VECTOR_INDEX	1
148 
149 /*
150  * For big-endian aarch64/armv7 on QEMU (and most real HW), only CPU cores
151  * are running in big-endian mode, with all peripheral being configured to
152  * little-endian mode. Their default bus_space(9) functions forcibly swap
153  * byte-order. This guarantees that PIO'ed data from pci(4), e.g., are
154  * correctly handled by bus_space(9), while DMA'ed ones should be swapped
155  * by hand, in violation of virtio(4) specifications.
156  */
157 
158 #if (defined(__aarch64__) || defined(__arm__)) && BYTE_ORDER == BIG_ENDIAN
159 #	define READ_ENDIAN_09	BIG_ENDIAN
160 #	define READ_ENDIAN_10	BIG_ENDIAN
161 #	define STRUCT_ENDIAN_09	BIG_ENDIAN
162 #	define STRUCT_ENDIAN_10	LITTLE_ENDIAN
163 #elif BYTE_ORDER == BIG_ENDIAN
164 #	define READ_ENDIAN_09	LITTLE_ENDIAN
165 #	define READ_ENDIAN_10	BIG_ENDIAN
166 #	define STRUCT_ENDIAN_09	BIG_ENDIAN
167 #	define STRUCT_ENDIAN_10	LITTLE_ENDIAN
168 #else /* little endian */
169 #	define READ_ENDIAN_09	LITTLE_ENDIAN
170 #	define READ_ENDIAN_10	LITTLE_ENDIAN
171 #	define STRUCT_ENDIAN_09	LITTLE_ENDIAN
172 #	define STRUCT_ENDIAN_10	LITTLE_ENDIAN
173 #endif
174 
175 
176 CFATTACH_DECL3_NEW(virtio_pci, sizeof(struct virtio_pci_softc),
177     virtio_pci_match, virtio_pci_attach, virtio_pci_detach, NULL,
178     virtio_pci_rescan, NULL, DVF_DETACH_SHUTDOWN);
179 
180 static const struct virtio_ops virtio_pci_ops_09 = {
181 	.kick = virtio_pci_kick_09,
182 	.read_queue_size = virtio_pci_read_queue_size_09,
183 	.setup_queue = virtio_pci_setup_queue_09,
184 	.set_status = virtio_pci_set_status_09,
185 	.neg_features = virtio_pci_negotiate_features_09,
186 	.alloc_interrupts = virtio_pci_alloc_interrupts,
187 	.free_interrupts = virtio_pci_free_interrupts,
188 	.setup_interrupts = virtio_pci_setup_interrupts_09,
189 };
190 
191 static const struct virtio_ops virtio_pci_ops_10 = {
192 	.kick = virtio_pci_kick_10,
193 	.read_queue_size = virtio_pci_read_queue_size_10,
194 	.setup_queue = virtio_pci_setup_queue_10,
195 	.set_status = virtio_pci_set_status_10,
196 	.neg_features = virtio_pci_negotiate_features_10,
197 	.alloc_interrupts = virtio_pci_alloc_interrupts,
198 	.free_interrupts = virtio_pci_free_interrupts,
199 	.setup_interrupts = virtio_pci_setup_interrupts_10,
200 };
201 
202 static int
203 virtio_pci_match(device_t parent, cfdata_t match, void *aux)
204 {
205 	struct pci_attach_args *pa;
206 
207 	pa = (struct pci_attach_args *)aux;
208 	switch (PCI_VENDOR(pa->pa_id)) {
209 	case PCI_VENDOR_QUMRANET:
210 		/* Transitional devices MUST have a PCI Revision ID of 0. */
211 		if (((PCI_PRODUCT_QUMRANET_VIRTIO_1000 <=
212 		      PCI_PRODUCT(pa->pa_id)) &&
213 		     (PCI_PRODUCT(pa->pa_id) <=
214 		      PCI_PRODUCT_QUMRANET_VIRTIO_103F)) &&
215 	              PCI_REVISION(pa->pa_class) == 0)
216 			return 1;
217 		/*
218 		 * Non-transitional devices SHOULD have a PCI Revision
219 		 * ID of 1 or higher.  Drivers MUST match any PCI
220 		 * Revision ID value.
221 		 */
222 		if (((PCI_PRODUCT_QUMRANET_VIRTIO_1040 <=
223 		      PCI_PRODUCT(pa->pa_id)) &&
224 		     (PCI_PRODUCT(pa->pa_id) <=
225 		      PCI_PRODUCT_QUMRANET_VIRTIO_107F)) &&
226 		      /* XXX: TODO */
227 		      PCI_REVISION(pa->pa_class) == 1)
228 			return 1;
229 		break;
230 	}
231 
232 	return 0;
233 }
234 
235 static void
236 virtio_pci_attach(device_t parent, device_t self, void *aux)
237 {
238 	struct virtio_pci_softc * const psc = device_private(self);
239 	struct virtio_softc * const sc = &psc->sc_sc;
240 	struct pci_attach_args *pa = (struct pci_attach_args *)aux;
241 	pci_chipset_tag_t pc = pa->pa_pc;
242 	pcitag_t tag = pa->pa_tag;
243 	int revision;
244 	int ret;
245 	pcireg_t id;
246 	pcireg_t csr;
247 
248 	revision = PCI_REVISION(pa->pa_class);
249 	switch (revision) {
250 	case 0:
251 		/* subsystem ID shows what I am */
252 		id = PCI_SUBSYS_ID(pci_conf_read(pc, tag, PCI_SUBSYS_ID_REG));
253 		break;
254 	case 1:
255 		/* pci product number shows what I am */
256 		id = PCI_PRODUCT(pa->pa_id) - PCI_PRODUCT_QUMRANET_VIRTIO_1040;
257 		break;
258 	default:
259 		aprint_normal(": unknown revision 0x%02x; giving up\n",
260 			      revision);
261 		return;
262 	}
263 
264 	aprint_normal("\n");
265 	aprint_naive("\n");
266 	virtio_print_device_type(self, id, revision);
267 
268 	csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
269 	csr |= PCI_COMMAND_MASTER_ENABLE | PCI_COMMAND_IO_ENABLE;
270 	pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
271 
272 	sc->sc_dev = self;
273 	psc->sc_pa = *pa;
274 	psc->sc_iot = pa->pa_iot;
275 
276 	sc->sc_dmat = pa->pa_dmat;
277 	if (pci_dma64_available(pa))
278 		sc->sc_dmat = pa->pa_dmat64;
279 
280 	/* attach is dependent on revision */
281 	ret = 0;
282 	if (revision == 1) {
283 		/* try to attach 1.0 */
284 		ret = virtio_pci_attach_10(self, aux);
285 	}
286 	if (ret == 0 && revision == 0) {
287 		/*
288 		 * revision 0 means 0.9 only or both 0.9 and 1.0.  The
289 		 * latter are so-called "Transitional Devices".  For
290 		 * those devices, we want to use the 1.0 interface if
291 		 * possible.
292 		 *
293 		 * XXX Currently only on platforms that require 1.0
294 		 * XXX features, such as VIRTIO_F_ACCESS_PLATFORM.
295 		 */
296 #ifdef __NEED_VIRTIO_F_ACCESS_PLATFORM
297 		/* First, try to attach 1.0 */
298 		ret = virtio_pci_attach_10(self, aux);
299 		if (ret != 0) {
300 			aprint_error_dev(self,
301 			    "VirtIO 1.0 error = %d, falling back to 0.9\n",
302 			    ret);
303 			/* Fall back to 0.9. */
304 			ret = virtio_pci_attach_09(self, aux);
305 		}
306 #else
307 		ret = virtio_pci_attach_09(self, aux);
308 #endif /* __NEED_VIRTIO_F_ACCESS_PLATFORM */
309 	}
310 	if (ret) {
311 		aprint_error_dev(self, "cannot attach (%d)\n", ret);
312 		return;
313 	}
314 	KASSERT(sc->sc_ops);
315 
316 	/* preset config region */
317 	psc->sc_devcfg_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
318 	if (virtio_pci_adjust_config_region(psc))
319 		return;
320 
321 	/* generic */
322 	virtio_device_reset(sc);
323 	virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_ACK);
324 	virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER);
325 
326 	sc->sc_childdevid = id;
327 	sc->sc_child = NULL;
328 	virtio_pci_rescan(self, NULL, NULL);
329 	return;
330 }
331 
332 /* ARGSUSED */
333 static int
334 virtio_pci_rescan(device_t self, const char *ifattr, const int *locs)
335 {
336 	struct virtio_pci_softc * const psc = device_private(self);
337 	struct virtio_softc * const sc = &psc->sc_sc;
338 	struct virtio_attach_args va;
339 
340 	if (sc->sc_child)	/* Child already attached? */
341 		return 0;
342 
343 	memset(&va, 0, sizeof(va));
344 	va.sc_childdevid = sc->sc_childdevid;
345 
346 	config_found(self, &va, NULL, CFARGS_NONE);
347 
348 	if (virtio_attach_failed(sc))
349 		return 0;
350 
351 	return 0;
352 }
353 
354 
355 static int
356 virtio_pci_detach(device_t self, int flags)
357 {
358 	struct virtio_pci_softc * const psc = device_private(self);
359 	struct virtio_softc * const sc = &psc->sc_sc;
360 	int r;
361 
362 	r = config_detach_children(self, flags);
363 	if (r != 0)
364 		return r;
365 
366 	/* Check that child never attached, or detached properly */
367 	KASSERT(sc->sc_child == NULL);
368 	KASSERT(sc->sc_vqs == NULL);
369 	KASSERT(psc->sc_ihs_num == 0);
370 
371 	if (psc->sc_iosize)
372 		bus_space_unmap(psc->sc_iot, psc->sc_ioh,
373 			psc->sc_mapped_iosize);
374 	psc->sc_iosize = 0;
375 
376 	return 0;
377 }
378 
379 
380 static int
381 virtio_pci_attach_09(device_t self, void *aux)
382 	//struct virtio_pci_softc *psc, struct pci_attach_args *pa)
383 {
384 	struct virtio_pci_softc * const psc = device_private(self);
385 	struct pci_attach_args *pa = (struct pci_attach_args *)aux;
386 	struct virtio_softc * const sc = &psc->sc_sc;
387 //	pci_chipset_tag_t pc = pa->pa_pc;
388 //	pcitag_t tag = pa->pa_tag;
389 
390 	/* complete IO region */
391 	if (pci_mapreg_map(pa, PCI_MAPREG_START, PCI_MAPREG_TYPE_IO, 0,
392 			   &psc->sc_iot, &psc->sc_ioh, NULL, &psc->sc_iosize)) {
393 		aprint_error_dev(self, "can't map i/o space\n");
394 		return EIO;
395 	}
396 	psc->sc_mapped_iosize = psc->sc_iosize;
397 
398 	/* queue space */
399 	if (bus_space_subregion(psc->sc_iot, psc->sc_ioh,
400 			VIRTIO_CONFIG_QUEUE_NOTIFY, 2, &psc->sc_notify_ioh)) {
401 		aprint_error_dev(self, "can't map notify i/o space\n");
402 		return EIO;
403 	}
404 	psc->sc_notify_iosize = 2;
405 	psc->sc_notify_iot = psc->sc_iot;
406 
407 	/* ISR space */
408 	if (bus_space_subregion(psc->sc_iot, psc->sc_ioh,
409 			VIRTIO_CONFIG_ISR_STATUS, 1, &psc->sc_isr_ioh)) {
410 		aprint_error_dev(self, "can't map isr i/o space\n");
411 		return EIO;
412 	}
413 	psc->sc_isr_iosize = 1;
414 	psc->sc_isr_iot = psc->sc_iot;
415 
416 	/* set our version 0.9 ops */
417 	sc->sc_ops = &virtio_pci_ops_09;
418 	sc->sc_bus_endian    = READ_ENDIAN_09;
419 	sc->sc_struct_endian = STRUCT_ENDIAN_09;
420 	return 0;
421 }
422 
423 
424 static int
425 virtio_pci_attach_10(device_t self, void *aux)
426 {
427 	struct virtio_pci_softc * const psc = device_private(self);
428 	struct pci_attach_args *pa = (struct pci_attach_args *)aux;
429 	struct virtio_softc * const sc = &psc->sc_sc;
430 	pci_chipset_tag_t pc = pa->pa_pc;
431 	pcitag_t tag = pa->pa_tag;
432 
433 	struct virtio_pci_cap common, isr, device;
434 	struct virtio_pci_notify_cap notify;
435 	int have_device_cfg = 0;
436 	bus_size_t bars[NMAPREG] = { 0 };
437 	int bars_idx[NMAPREG] = { 0 };
438 	struct virtio_pci_cap *caps[] = { &common, &isr, &device, &notify.cap };
439 	int i, j, ret = 0;
440 
441 	if (virtio_pci_find_cap(psc, VIRTIO_PCI_CAP_COMMON_CFG,
442 			&common, sizeof(common)))
443 		return ENODEV;
444 	if (virtio_pci_find_cap(psc, VIRTIO_PCI_CAP_NOTIFY_CFG,
445 			&notify, sizeof(notify)))
446 		return ENODEV;
447 	if (virtio_pci_find_cap(psc, VIRTIO_PCI_CAP_ISR_CFG,
448 			&isr, sizeof(isr)))
449 		return ENODEV;
450 	if (virtio_pci_find_cap(psc, VIRTIO_PCI_CAP_DEVICE_CFG,
451 			&device, sizeof(device)))
452 		memset(&device, 0, sizeof(device));
453 	else
454 		have_device_cfg = 1;
455 
456 	/* Figure out which bars we need to map */
457 	for (i = 0; i < __arraycount(caps); i++) {
458 		int bar = caps[i]->bar;
459 		bus_size_t len = caps[i]->offset + caps[i]->length;
460 		if (caps[i]->length == 0)
461 			continue;
462 		if (bars[bar] < len)
463 			bars[bar] = len;
464 	}
465 
466 	for (i = j = 0; i < __arraycount(bars); i++) {
467 		int reg;
468 		pcireg_t type;
469 		if (bars[i] == 0)
470 			continue;
471 		reg = PCI_BAR(i);
472 		type = pci_mapreg_type(pc, tag, reg);
473 		if (pci_mapreg_map(pa, reg, type, 0,
474 				&psc->sc_bars_iot[j], &psc->sc_bars_ioh[j],
475 				NULL, &psc->sc_bars_iosize[j])) {
476 			aprint_error_dev(self, "can't map bar %u \n", i);
477 			ret = EIO;
478 			goto err;
479 		}
480 		aprint_debug_dev(self,
481 		    "bar[%d]: iot %p, size 0x%" PRIxBUSSIZE "\n",
482 		    j, psc->sc_bars_iot[j], psc->sc_bars_iosize[j]);
483 		bars_idx[i] = j;
484 		j++;
485 	}
486 
487 	i = bars_idx[notify.cap.bar];
488 	if (bus_space_subregion(psc->sc_bars_iot[i], psc->sc_bars_ioh[i],
489 			notify.cap.offset, notify.cap.length,
490 			&psc->sc_notify_ioh)) {
491 		aprint_error_dev(self, "can't map notify i/o space\n");
492 		ret = EIO;
493 		goto err;
494 	}
495 	psc->sc_notify_iosize = notify.cap.length;
496 	psc->sc_notify_iot = psc->sc_bars_iot[i];
497 	psc->sc_notify_off_multiplier = le32toh(notify.notify_off_multiplier);
498 
499 	if (have_device_cfg) {
500 		i = bars_idx[device.bar];
501 		if (bus_space_subregion(psc->sc_bars_iot[i], psc->sc_bars_ioh[i],
502 				device.offset, device.length,
503 				&sc->sc_devcfg_ioh)) {
504 			aprint_error_dev(self, "can't map devcfg i/o space\n");
505 			ret = EIO;
506 			goto err;
507 		}
508 		aprint_debug_dev(self,
509 			"device.offset = 0x%x, device.length = 0x%x\n",
510 			device.offset, device.length);
511 		sc->sc_devcfg_iosize = device.length;
512 		sc->sc_devcfg_iot = psc->sc_bars_iot[i];
513 	}
514 
515 	i = bars_idx[isr.bar];
516 	if (bus_space_subregion(psc->sc_bars_iot[i], psc->sc_bars_ioh[i],
517 			isr.offset, isr.length, &psc->sc_isr_ioh)) {
518 		aprint_error_dev(self, "can't map isr i/o space\n");
519 		ret = EIO;
520 		goto err;
521 	}
522 	psc->sc_isr_iosize = isr.length;
523 	psc->sc_isr_iot = psc->sc_bars_iot[i];
524 
525 	i = bars_idx[common.bar];
526 	if (bus_space_subregion(psc->sc_bars_iot[i], psc->sc_bars_ioh[i],
527 			common.offset, common.length, &psc->sc_ioh)) {
528 		aprint_error_dev(self, "can't map common i/o space\n");
529 		ret = EIO;
530 		goto err;
531 	}
532 	psc->sc_iosize = common.length;
533 	psc->sc_iot = psc->sc_bars_iot[i];
534 	psc->sc_mapped_iosize = psc->sc_bars_iosize[i];
535 
536 	psc->sc_sc.sc_version_1 = 1;
537 
538 	/* set our version 1.0 ops */
539 	sc->sc_ops = &virtio_pci_ops_10;
540 	sc->sc_bus_endian    = READ_ENDIAN_10;
541 	sc->sc_struct_endian = STRUCT_ENDIAN_10;
542 	return 0;
543 
544 err:
545 	/* undo our pci_mapreg_map()s */
546 	for (i = 0; i < __arraycount(bars); i++) {
547 		if (psc->sc_bars_iosize[i] == 0)
548 			continue;
549 		bus_space_unmap(psc->sc_bars_iot[i], psc->sc_bars_ioh[i],
550 				psc->sc_bars_iosize[i]);
551 	}
552 	return ret;
553 }
554 
555 /* v1.0 attach helper */
556 static int
557 virtio_pci_find_cap(struct virtio_pci_softc *psc, int cfg_type, void *buf, int buflen)
558 {
559 	device_t self = psc->sc_sc.sc_dev;
560 	pci_chipset_tag_t pc = psc->sc_pa.pa_pc;
561 	pcitag_t tag = psc->sc_pa.pa_tag;
562 	unsigned int offset, i, len;
563 	union {
564 		pcireg_t reg[8];
565 		struct virtio_pci_cap vcap;
566 	} *v = buf;
567 
568 	if (buflen < sizeof(struct virtio_pci_cap))
569 		return ERANGE;
570 
571 	if (!pci_get_capability(pc, tag, PCI_CAP_VENDSPEC, &offset, &v->reg[0]))
572 		return ENOENT;
573 
574 	do {
575 		for (i = 0; i < 4; i++)
576 			v->reg[i] =
577 				le32toh(pci_conf_read(pc, tag, offset + i * 4));
578 		if (v->vcap.cfg_type == cfg_type)
579 			break;
580 		offset = v->vcap.cap_next;
581 	} while (offset != 0);
582 
583 	if (offset == 0)
584 		return ENOENT;
585 
586 	if (v->vcap.cap_len > sizeof(struct virtio_pci_cap)) {
587 		len = roundup(v->vcap.cap_len, sizeof(pcireg_t));
588 		if (len > buflen) {
589 			aprint_error_dev(self, "%s cap too large\n", __func__);
590 			return ERANGE;
591 		}
592 		for (i = 4; i < len / sizeof(pcireg_t);  i++)
593 			v->reg[i] =
594 				le32toh(pci_conf_read(pc, tag, offset + i * 4));
595 	}
596 
597 	/* endian fixup */
598 	v->vcap.offset = le32toh(v->vcap.offset);
599 	v->vcap.length = le32toh(v->vcap.length);
600 	return 0;
601 }
602 
603 
604 /* -------------------------------------
605  * Version 0.9 support
606  * -------------------------------------*/
607 
608 static void
609 virtio_pci_kick_09(struct virtio_softc *sc, uint16_t idx)
610 {
611 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
612 
613 	bus_space_write_2(psc->sc_notify_iot, psc->sc_notify_ioh, 0, idx);
614 }
615 
616 /* only applicable for v 0.9 but also called for 1.0 */
617 static int
618 virtio_pci_adjust_config_region(struct virtio_pci_softc *psc)
619 {
620 	struct virtio_softc * const sc = &psc->sc_sc;
621 	device_t self = sc->sc_dev;
622 
623 	if (psc->sc_sc.sc_version_1)
624 		return 0;
625 
626 	sc->sc_devcfg_iosize = psc->sc_iosize - psc->sc_devcfg_offset;
627 	sc->sc_devcfg_iot = psc->sc_iot;
628 	if (bus_space_subregion(psc->sc_iot, psc->sc_ioh,
629 			psc->sc_devcfg_offset, sc->sc_devcfg_iosize,
630 			&sc->sc_devcfg_ioh)) {
631 		aprint_error_dev(self, "can't map config i/o space\n");
632 		return EIO;
633 	}
634 
635 	return 0;
636 }
637 
638 static uint16_t
639 virtio_pci_read_queue_size_09(struct virtio_softc *sc, uint16_t idx)
640 {
641 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
642 
643 	bus_space_write_2(psc->sc_iot, psc->sc_ioh,
644 	    VIRTIO_CONFIG_QUEUE_SELECT, idx);
645 	return bus_space_read_2(psc->sc_iot, psc->sc_ioh,
646 	    VIRTIO_CONFIG_QUEUE_SIZE);
647 }
648 
649 static void
650 virtio_pci_setup_queue_09(struct virtio_softc *sc, uint16_t idx, uint64_t addr)
651 {
652 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
653 
654 	bus_space_write_2(psc->sc_iot, psc->sc_ioh,
655 	    VIRTIO_CONFIG_QUEUE_SELECT, idx);
656 	bus_space_write_4(psc->sc_iot, psc->sc_ioh,
657 	    VIRTIO_CONFIG_QUEUE_ADDRESS, addr / VIRTIO_PAGE_SIZE);
658 
659 	if (psc->sc_ihs_num > 1) {
660 		int vec = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
661 		if (psc->sc_intr_pervq)
662 			vec += idx;
663 		bus_space_write_2(psc->sc_iot, psc->sc_ioh,
664 		    VIRTIO_CONFIG_MSI_QUEUE_VECTOR, vec);
665 	}
666 }
667 
668 static void
669 virtio_pci_set_status_09(struct virtio_softc *sc, int status)
670 {
671 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
672 	int old = 0;
673 
674 	if (status != 0) {
675 	    old = bus_space_read_1(psc->sc_iot, psc->sc_ioh,
676 		VIRTIO_CONFIG_DEVICE_STATUS);
677 	}
678 	bus_space_write_1(psc->sc_iot, psc->sc_ioh,
679 	    VIRTIO_CONFIG_DEVICE_STATUS, status|old);
680 }
681 
682 static void
683 virtio_pci_negotiate_features_09(struct virtio_softc *sc, uint64_t guest_features)
684 {
685 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
686 	uint32_t r;
687 
688 	r = bus_space_read_4(psc->sc_iot, psc->sc_ioh,
689 	    VIRTIO_CONFIG_DEVICE_FEATURES);
690 
691 	r &= guest_features;
692 
693 	bus_space_write_4(psc->sc_iot, psc->sc_ioh,
694 	    VIRTIO_CONFIG_GUEST_FEATURES, r);
695 
696 	sc->sc_active_features = r;
697 }
698 
699 /* -------------------------------------
700  * Version 1.0 support
701  * -------------------------------------*/
702 
703 static void
704 virtio_pci_kick_10(struct virtio_softc *sc, uint16_t idx)
705 {
706 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
707 	unsigned offset = sc->sc_vqs[idx].vq_notify_off *
708 		psc->sc_notify_off_multiplier;
709 
710 	bus_space_write_2(psc->sc_notify_iot, psc->sc_notify_ioh, offset, idx);
711 }
712 
713 
714 static uint16_t
715 virtio_pci_read_queue_size_10(struct virtio_softc *sc, uint16_t idx)
716 {
717 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
718 	bus_space_tag_t	   iot = psc->sc_iot;
719 	bus_space_handle_t ioh = psc->sc_ioh;
720 
721 	bus_space_write_2(iot, ioh, VIRTIO_CONFIG1_QUEUE_SELECT, idx);
722 	return bus_space_read_2(iot, ioh, VIRTIO_CONFIG1_QUEUE_SIZE);
723 }
724 
725 /*
726  * By definition little endian only in v1.0.  NB: "MAY" in the text
727  * below refers to "independently" (i.e. the order of accesses) not
728  * "32-bit" (which is restricted by the earlier "MUST").
729  *
730  * 4.1.3.1 Driver Requirements: PCI Device Layout
731  *
732  * For device configuration access, the driver MUST use ... 32-bit
733  * wide and aligned accesses for ... 64-bit wide fields.  For 64-bit
734  * fields, the driver MAY access each of the high and low 32-bit parts
735  * of the field independently.
736  */
737 static __inline void
738 virtio_pci_bus_space_write_8(bus_space_tag_t iot, bus_space_handle_t ioh,
739      bus_size_t offset, uint64_t value)
740 {
741 #if _QUAD_HIGHWORD
742 	bus_space_write_4(iot, ioh, offset, BUS_ADDR_LO32(value));
743 	bus_space_write_4(iot, ioh, offset + 4, BUS_ADDR_HI32(value));
744 #else
745 	bus_space_write_4(iot, ioh, offset, BUS_ADDR_HI32(value));
746 	bus_space_write_4(iot, ioh, offset + 4, BUS_ADDR_LO32(value));
747 #endif
748 }
749 
750 static void
751 virtio_pci_setup_queue_10(struct virtio_softc *sc, uint16_t idx, uint64_t addr)
752 {
753 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
754 	struct virtqueue *vq = &sc->sc_vqs[idx];
755 	bus_space_tag_t	   iot = psc->sc_iot;
756 	bus_space_handle_t ioh = psc->sc_ioh;
757 	KASSERT(vq->vq_index == idx);
758 
759 	bus_space_write_2(iot, ioh, VIRTIO_CONFIG1_QUEUE_SELECT, vq->vq_index);
760 	if (addr == 0) {
761 		bus_space_write_2(iot, ioh, VIRTIO_CONFIG1_QUEUE_ENABLE, 0);
762 		virtio_pci_bus_space_write_8(iot, ioh,
763 		    VIRTIO_CONFIG1_QUEUE_DESC,   0);
764 		virtio_pci_bus_space_write_8(iot, ioh,
765 		    VIRTIO_CONFIG1_QUEUE_AVAIL,  0);
766 		virtio_pci_bus_space_write_8(iot, ioh,
767 		    VIRTIO_CONFIG1_QUEUE_USED,   0);
768 	} else {
769 		virtio_pci_bus_space_write_8(iot, ioh,
770 			VIRTIO_CONFIG1_QUEUE_DESC, addr);
771 		virtio_pci_bus_space_write_8(iot, ioh,
772 			VIRTIO_CONFIG1_QUEUE_AVAIL, addr + vq->vq_availoffset);
773 		virtio_pci_bus_space_write_8(iot, ioh,
774 			VIRTIO_CONFIG1_QUEUE_USED, addr + vq->vq_usedoffset);
775 		bus_space_write_2(iot, ioh,
776 			VIRTIO_CONFIG1_QUEUE_ENABLE, 1);
777 		vq->vq_notify_off = bus_space_read_2(iot, ioh,
778 			VIRTIO_CONFIG1_QUEUE_NOTIFY_OFF);
779 	}
780 
781 	if (psc->sc_ihs_num > 1) {
782 		int vec = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
783 		if (psc->sc_intr_pervq)
784 			vec += idx;
785 		bus_space_write_2(iot, ioh,
786 			VIRTIO_CONFIG1_QUEUE_MSIX_VECTOR, vec);
787 	}
788 }
789 
790 static void
791 virtio_pci_set_status_10(struct virtio_softc *sc, int status)
792 {
793 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
794 	bus_space_tag_t	   iot = psc->sc_iot;
795 	bus_space_handle_t ioh = psc->sc_ioh;
796 	int old = 0;
797 
798 	if (status)
799 		old = bus_space_read_1(iot, ioh, VIRTIO_CONFIG1_DEVICE_STATUS);
800 	bus_space_write_1(iot, ioh, VIRTIO_CONFIG1_DEVICE_STATUS, status | old);
801 }
802 
803 void
804 virtio_pci_negotiate_features_10(struct virtio_softc *sc, uint64_t guest_features)
805 {
806 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
807 	device_t self          =  sc->sc_dev;
808 	bus_space_tag_t	   iot = psc->sc_iot;
809 	bus_space_handle_t ioh = psc->sc_ioh;
810 	uint64_t host, negotiated, device_status;
811 
812 	guest_features |= VIRTIO_F_VERSION_1;
813 #ifdef __NEED_VIRTIO_F_ACCESS_PLATFORM
814 	/* XXX This could use some work. */
815 	guest_features |= VIRTIO_F_ACCESS_PLATFORM;
816 #endif /* __NEED_VIRTIO_F_ACCESS_PLATFORM */
817 	/* notify on empty is 0.9 only */
818 	guest_features &= ~VIRTIO_F_NOTIFY_ON_EMPTY;
819 	sc->sc_active_features = 0;
820 
821 	bus_space_write_4(iot, ioh, VIRTIO_CONFIG1_DEVICE_FEATURE_SELECT, 0);
822 	host = bus_space_read_4(iot, ioh, VIRTIO_CONFIG1_DEVICE_FEATURE);
823 	bus_space_write_4(iot, ioh, VIRTIO_CONFIG1_DEVICE_FEATURE_SELECT, 1);
824 	host |= (uint64_t)
825 		bus_space_read_4(iot, ioh, VIRTIO_CONFIG1_DEVICE_FEATURE) << 32;
826 
827 	negotiated = host & guest_features;
828 
829 	bus_space_write_4(iot, ioh, VIRTIO_CONFIG1_DRIVER_FEATURE_SELECT, 0);
830 	bus_space_write_4(iot, ioh, VIRTIO_CONFIG1_DRIVER_FEATURE,
831 			negotiated & 0xffffffff);
832 	bus_space_write_4(iot, ioh, VIRTIO_CONFIG1_DRIVER_FEATURE_SELECT, 1);
833 	bus_space_write_4(iot, ioh, VIRTIO_CONFIG1_DRIVER_FEATURE,
834 			negotiated >> 32);
835 	virtio_pci_set_status_10(sc, VIRTIO_CONFIG_DEVICE_STATUS_FEATURES_OK);
836 
837 	device_status = bus_space_read_1(iot, ioh, VIRTIO_CONFIG1_DEVICE_STATUS);
838 	if ((device_status & VIRTIO_CONFIG_DEVICE_STATUS_FEATURES_OK) == 0) {
839 		aprint_error_dev(self, "feature negotiation failed\n");
840 		bus_space_write_1(iot, ioh, VIRTIO_CONFIG1_DEVICE_STATUS,
841 				VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
842 		return;
843 	}
844 
845 	if ((negotiated & VIRTIO_F_VERSION_1) == 0) {
846 		aprint_error_dev(self, "host rejected version 1\n");
847 		bus_space_write_1(iot, ioh, VIRTIO_CONFIG1_DEVICE_STATUS,
848 				VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
849 		return;
850 	}
851 
852 	sc->sc_active_features = negotiated;
853 	return;
854 }
855 
856 
857 /* -------------------------------------
858  * Generic PCI interrupt code
859  * -------------------------------------*/
860 
861 static int
862 virtio_pci_setup_interrupts_10(struct virtio_softc *sc, int reinit)
863 {
864 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
865 	bus_space_tag_t	   iot = psc->sc_iot;
866 	bus_space_handle_t ioh = psc->sc_ioh;
867 	int vector, ret, qid;
868 
869 	if (!virtio_pci_msix_enabled(psc))
870 		return 0;
871 
872 	vector = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
873 	bus_space_write_2(iot, ioh,
874 		VIRTIO_CONFIG1_CONFIG_MSIX_VECTOR, vector);
875 	ret = bus_space_read_2(iot, ioh, VIRTIO_CONFIG1_CONFIG_MSIX_VECTOR);
876 	if (ret != vector) {
877 		VIRTIO_PCI_LOG(sc, reinit,
878 		    "can't set config msix vector\n");
879 		return -1;
880 	}
881 
882 	for (qid = 0; qid < sc->sc_nvqs; qid++) {
883 		vector = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
884 
885 		if (psc->sc_intr_pervq)
886 			vector += qid;
887 		bus_space_write_2(iot, ioh, VIRTIO_CONFIG1_QUEUE_SELECT, qid);
888 		bus_space_write_2(iot, ioh, VIRTIO_CONFIG1_QUEUE_MSIX_VECTOR,
889 			vector);
890 		ret = bus_space_read_2(iot, ioh,
891 			VIRTIO_CONFIG1_QUEUE_MSIX_VECTOR);
892 		if (ret != vector) {
893 			VIRTIO_PCI_LOG(sc, reinit, "can't set queue %d "
894 			    "msix vector\n", qid);
895 			return -1;
896 		}
897 	}
898 
899 	return 0;
900 }
901 
902 static int
903 virtio_pci_setup_interrupts_09(struct virtio_softc *sc, int reinit)
904 {
905 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
906 	int offset, vector, ret, qid;
907 
908 	if (!virtio_pci_msix_enabled(psc))
909 		return 0;
910 
911 	offset = VIRTIO_CONFIG_MSI_CONFIG_VECTOR;
912 	vector = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
913 
914 	bus_space_write_2(psc->sc_iot, psc->sc_ioh, offset, vector);
915 	ret = bus_space_read_2(psc->sc_iot, psc->sc_ioh, offset);
916 	if (ret != vector) {
917 		aprint_debug_dev(sc->sc_dev, "%s: expected=%d, actual=%d\n",
918 		    __func__, vector, ret);
919 		VIRTIO_PCI_LOG(sc, reinit,
920 		    "can't set config msix vector\n");
921 		return -1;
922 	}
923 
924 	for (qid = 0; qid < sc->sc_nvqs; qid++) {
925 		offset = VIRTIO_CONFIG_QUEUE_SELECT;
926 		bus_space_write_2(psc->sc_iot, psc->sc_ioh, offset, qid);
927 
928 		offset = VIRTIO_CONFIG_MSI_QUEUE_VECTOR;
929 		vector = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
930 
931 		if (psc->sc_intr_pervq)
932 			vector += qid;
933 
934 		bus_space_write_2(psc->sc_iot, psc->sc_ioh, offset, vector);
935 		ret = bus_space_read_2(psc->sc_iot, psc->sc_ioh, offset);
936 		if (ret != vector) {
937 			aprint_debug_dev(sc->sc_dev, "%s[qid=%d]:"
938 			    " expected=%d, actual=%d\n",
939 			    __func__, qid, vector, ret);
940 			VIRTIO_PCI_LOG(sc, reinit, "can't set queue %d "
941 			    "msix vector\n", qid);
942 			return -1;
943 		}
944 	}
945 
946 	return 0;
947 }
948 
949 static int
950 virtio_pci_establish_msix_interrupts(struct virtio_softc *sc,
951     struct pci_attach_args *pa)
952 {
953 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
954 	device_t self = sc->sc_dev;
955 	pci_chipset_tag_t pc = pa->pa_pc;
956 	struct virtqueue *vq;
957 	char intrbuf[PCI_INTRSTR_LEN];
958 	char intr_xname[INTRDEVNAMEBUF];
959 	char const *intrstr;
960 	int idx, qid, n;
961 
962 	idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
963 	if (sc->sc_flags & VIRTIO_F_INTR_MPSAFE)
964 		pci_intr_setattr(pc, &psc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
965 
966 	snprintf(intr_xname, sizeof(intr_xname), "%s config",
967 	    device_xname(sc->sc_dev));
968 
969 	psc->sc_ihs[idx] = pci_intr_establish_xname(pc, psc->sc_ihp[idx],
970 	    sc->sc_ipl, virtio_pci_msix_config_intr, sc, intr_xname);
971 	if (psc->sc_ihs[idx] == NULL) {
972 		aprint_error_dev(self, "couldn't establish MSI-X for config\n");
973 		goto error;
974 	}
975 
976 	idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
977 	if (psc->sc_intr_pervq) {
978 		for (qid = 0; qid < sc->sc_nvqs; qid++) {
979 			n = idx + qid;
980 			vq = &sc->sc_vqs[qid];
981 
982 			snprintf(intr_xname, sizeof(intr_xname), "%s vq#%d",
983 			    device_xname(sc->sc_dev), qid);
984 
985 			if (sc->sc_flags & VIRTIO_F_INTR_MPSAFE) {
986 				pci_intr_setattr(pc, &psc->sc_ihp[n],
987 				    PCI_INTR_MPSAFE, true);
988 			}
989 
990 			psc->sc_ihs[n] = pci_intr_establish_xname(pc, psc->sc_ihp[n],
991 			    sc->sc_ipl, vq->vq_intrhand, vq->vq_intrhand_arg, intr_xname);
992 			if (psc->sc_ihs[n] == NULL) {
993 				aprint_error_dev(self, "couldn't establish MSI-X for a vq\n");
994 				goto error;
995 			}
996 		}
997 	} else {
998 		if (sc->sc_flags & VIRTIO_F_INTR_MPSAFE)
999 			pci_intr_setattr(pc, &psc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
1000 
1001 		snprintf(intr_xname, sizeof(intr_xname), "%s queues",
1002 		    device_xname(sc->sc_dev));
1003 		psc->sc_ihs[idx] = pci_intr_establish_xname(pc, psc->sc_ihp[idx],
1004 		    sc->sc_ipl, virtio_pci_msix_queue_intr, sc, intr_xname);
1005 		if (psc->sc_ihs[idx] == NULL) {
1006 			aprint_error_dev(self, "couldn't establish MSI-X for queues\n");
1007 			goto error;
1008 		}
1009 	}
1010 
1011 	idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
1012 	intrstr = pci_intr_string(pc, psc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
1013 	aprint_normal_dev(self, "config interrupting at %s\n", intrstr);
1014 	idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
1015 	if (psc->sc_intr_pervq) {
1016 		kcpuset_t *affinity;
1017 		int affinity_to, r;
1018 
1019 		kcpuset_create(&affinity, false);
1020 
1021 		for (qid = 0; qid < sc->sc_nvqs; qid++) {
1022 			n = idx + qid;
1023 			affinity_to = (qid / 2) % ncpu;
1024 
1025 			intrstr = pci_intr_string(pc, psc->sc_ihp[n],
1026 			    intrbuf, sizeof(intrbuf));
1027 
1028 			kcpuset_zero(affinity);
1029 			kcpuset_set(affinity, affinity_to);
1030 			r = interrupt_distribute(psc->sc_ihs[n], affinity, NULL);
1031 			if (r == 0) {
1032 				aprint_normal_dev(self,
1033 				    "for vq #%d interrupting at %s affinity to %u\n",
1034 				    qid, intrstr, affinity_to);
1035 			} else {
1036 				aprint_normal_dev(self,
1037 				    "for vq #%d interrupting at %s\n",
1038 				    qid, intrstr);
1039 			}
1040 		}
1041 
1042 		kcpuset_destroy(affinity);
1043 	} else {
1044 		intrstr = pci_intr_string(pc, psc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
1045 		aprint_normal_dev(self, "queues interrupting at %s\n", intrstr);
1046 	}
1047 
1048 	return 0;
1049 
1050 error:
1051 	idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
1052 	if (psc->sc_ihs[idx] != NULL)
1053 		pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[idx]);
1054 	idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
1055 	if (psc->sc_intr_pervq) {
1056 		for (qid = 0; qid < sc->sc_nvqs; qid++) {
1057 			n = idx + qid;
1058 			if (psc->sc_ihs[n] == NULL)
1059 				continue;
1060 			pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[n]);
1061 		}
1062 
1063 	} else {
1064 		if (psc->sc_ihs[idx] != NULL)
1065 			pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[idx]);
1066 	}
1067 
1068 	return -1;
1069 }
1070 
1071 static int
1072 virtio_pci_establish_intx_interrupt(struct virtio_softc *sc,
1073     struct pci_attach_args *pa)
1074 {
1075 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
1076 	device_t self = sc->sc_dev;
1077 	pci_chipset_tag_t pc = pa->pa_pc;
1078 	char intrbuf[PCI_INTRSTR_LEN];
1079 	char const *intrstr;
1080 
1081 	if (sc->sc_flags & VIRTIO_F_INTR_MPSAFE)
1082 		pci_intr_setattr(pc, &psc->sc_ihp[0], PCI_INTR_MPSAFE, true);
1083 
1084 	psc->sc_ihs[0] = pci_intr_establish_xname(pc, psc->sc_ihp[0],
1085 	    sc->sc_ipl, virtio_pci_intr, sc, device_xname(sc->sc_dev));
1086 	if (psc->sc_ihs[0] == NULL) {
1087 		aprint_error_dev(self, "couldn't establish INTx\n");
1088 		return -1;
1089 	}
1090 
1091 	intrstr = pci_intr_string(pc, psc->sc_ihp[0], intrbuf, sizeof(intrbuf));
1092 	aprint_normal_dev(self, "interrupting at %s\n", intrstr);
1093 
1094 	return 0;
1095 }
1096 
1097 static int
1098 virtio_pci_alloc_interrupts(struct virtio_softc *sc)
1099 {
1100 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
1101 	device_t self = sc->sc_dev;
1102 	pci_chipset_tag_t pc = psc->sc_pa.pa_pc;
1103 	pcitag_t tag = psc->sc_pa.pa_tag;
1104 	int error;
1105 	int nmsix;
1106 	int off;
1107 	int counts[PCI_INTR_TYPE_SIZE];
1108 	pci_intr_type_t max_type;
1109 	pcireg_t ctl;
1110 
1111 	nmsix = pci_msix_count(psc->sc_pa.pa_pc, psc->sc_pa.pa_tag);
1112 	aprint_debug_dev(self, "pci_msix_count=%d\n", nmsix);
1113 
1114 	/* We need at least two: one for config and the other for queues */
1115 	if ((sc->sc_flags & VIRTIO_F_INTR_MSIX) == 0 || nmsix < 2) {
1116 		/* Try INTx only */
1117 		max_type = PCI_INTR_TYPE_INTX;
1118 		counts[PCI_INTR_TYPE_INTX] = 1;
1119 	} else {
1120 		/* Try MSI-X first and INTx second */
1121 		if (ISSET(sc->sc_flags, VIRTIO_F_INTR_PERVQ) &&
1122 		    sc->sc_nvqs + VIRTIO_MSIX_QUEUE_VECTOR_INDEX <= nmsix) {
1123 			nmsix = sc->sc_nvqs + VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
1124 		} else {
1125 			nmsix = 2;
1126 		}
1127 
1128 		max_type = PCI_INTR_TYPE_MSIX;
1129 		counts[PCI_INTR_TYPE_MSIX] = nmsix;
1130 		counts[PCI_INTR_TYPE_MSI] = 0;
1131 		counts[PCI_INTR_TYPE_INTX] = 1;
1132 	}
1133 
1134 retry:
1135 	error = pci_intr_alloc(&psc->sc_pa, &psc->sc_ihp, counts, max_type);
1136 	if (error != 0) {
1137 		aprint_error_dev(self, "couldn't map interrupt\n");
1138 		return -1;
1139 	}
1140 
1141 	if (pci_intr_type(pc, psc->sc_ihp[0]) == PCI_INTR_TYPE_MSIX) {
1142 		psc->sc_intr_pervq = nmsix > 2 ? true : false;
1143 		psc->sc_ihs = kmem_zalloc(sizeof(*psc->sc_ihs) * nmsix,
1144 		    KM_SLEEP);
1145 
1146 		error = virtio_pci_establish_msix_interrupts(sc, &psc->sc_pa);
1147 		if (error != 0) {
1148 			kmem_free(psc->sc_ihs, sizeof(*psc->sc_ihs) * nmsix);
1149 			pci_intr_release(pc, psc->sc_ihp, nmsix);
1150 
1151 			/* Retry INTx */
1152 			max_type = PCI_INTR_TYPE_INTX;
1153 			counts[PCI_INTR_TYPE_INTX] = 1;
1154 			goto retry;
1155 		}
1156 
1157 		psc->sc_ihs_num = nmsix;
1158 		psc->sc_devcfg_offset = VIRTIO_CONFIG_DEVICE_CONFIG_MSI;
1159 		virtio_pci_adjust_config_region(psc);
1160 	} else if (pci_intr_type(pc, psc->sc_ihp[0]) == PCI_INTR_TYPE_INTX) {
1161 		psc->sc_intr_pervq = false;
1162 		psc->sc_ihs = kmem_zalloc(sizeof(*psc->sc_ihs) * 1,
1163 		    KM_SLEEP);
1164 
1165 		error = virtio_pci_establish_intx_interrupt(sc, &psc->sc_pa);
1166 		if (error != 0) {
1167 			kmem_free(psc->sc_ihs, sizeof(*psc->sc_ihs) * 1);
1168 			pci_intr_release(pc, psc->sc_ihp, 1);
1169 			return -1;
1170 		}
1171 
1172 		psc->sc_ihs_num = 1;
1173 		psc->sc_devcfg_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
1174 		virtio_pci_adjust_config_region(psc);
1175 
1176 		error = pci_get_capability(pc, tag, PCI_CAP_MSIX, &off, NULL);
1177 		if (error != 0) {
1178 			ctl = pci_conf_read(pc, tag, off + PCI_MSIX_CTL);
1179 			ctl &= ~PCI_MSIX_CTL_ENABLE;
1180 			pci_conf_write(pc, tag, off + PCI_MSIX_CTL, ctl);
1181 		}
1182 	}
1183 
1184 	if (!psc->sc_intr_pervq)
1185 		CLR(sc->sc_flags, VIRTIO_F_INTR_PERVQ);
1186 	return 0;
1187 }
1188 
1189 static void
1190 virtio_pci_free_interrupts(struct virtio_softc *sc)
1191 {
1192 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
1193 
1194 	for (int i = 0; i < psc->sc_ihs_num; i++) {
1195 		if (psc->sc_ihs[i] == NULL)
1196 			continue;
1197 		pci_intr_disestablish(psc->sc_pa.pa_pc, psc->sc_ihs[i]);
1198 		psc->sc_ihs[i] = NULL;
1199 	}
1200 
1201 	if (psc->sc_ihs_num > 0)
1202 		pci_intr_release(psc->sc_pa.pa_pc, psc->sc_ihp, psc->sc_ihs_num);
1203 
1204 	if (psc->sc_ihs != NULL) {
1205 		kmem_free(psc->sc_ihs, sizeof(*psc->sc_ihs) * psc->sc_ihs_num);
1206 		psc->sc_ihs = NULL;
1207 	}
1208 	psc->sc_ihs_num = 0;
1209 }
1210 
1211 static bool
1212 virtio_pci_msix_enabled(struct virtio_pci_softc *psc)
1213 {
1214 	pci_chipset_tag_t pc = psc->sc_pa.pa_pc;
1215 
1216 	if (pci_intr_type(pc, psc->sc_ihp[0]) == PCI_INTR_TYPE_MSIX)
1217 		return true;
1218 
1219 	return false;
1220 }
1221 
1222 /*
1223  * Interrupt handler.
1224  */
1225 static int
1226 virtio_pci_intr(void *arg)
1227 {
1228 	struct virtio_softc *sc = arg;
1229 	struct virtio_pci_softc * const psc = (struct virtio_pci_softc *)sc;
1230 	int isr, r = 0;
1231 
1232 	/* check and ack the interrupt */
1233 	isr = bus_space_read_1(psc->sc_isr_iot, psc->sc_isr_ioh, 0);
1234 	if (isr == 0)
1235 		return 0;
1236 	if ((isr & VIRTIO_CONFIG_ISR_CONFIG_CHANGE) &&
1237 	    (sc->sc_config_change != NULL))
1238 		r = (sc->sc_config_change)(sc);
1239 	if (sc->sc_intrhand != NULL) {
1240 		if (sc->sc_soft_ih != NULL)
1241 			softint_schedule(sc->sc_soft_ih);
1242 		else
1243 			r |= (sc->sc_intrhand)(sc);
1244 	}
1245 
1246 	return r;
1247 }
1248 
1249 static int
1250 virtio_pci_msix_queue_intr(void *arg)
1251 {
1252 	struct virtio_softc *sc = arg;
1253 	int r = 0;
1254 
1255 	if (sc->sc_intrhand != NULL) {
1256 		if (sc->sc_soft_ih != NULL)
1257 			softint_schedule(sc->sc_soft_ih);
1258 		else
1259 			r |= (sc->sc_intrhand)(sc);
1260 	}
1261 
1262 	return r;
1263 }
1264 
1265 static int
1266 virtio_pci_msix_config_intr(void *arg)
1267 {
1268 	struct virtio_softc *sc = arg;
1269 	int r = 0;
1270 
1271 	if (sc->sc_config_change != NULL)
1272 		r = (sc->sc_config_change)(sc);
1273 	return r;
1274 }
1275 
1276 MODULE(MODULE_CLASS_DRIVER, virtio_pci, "pci,virtio");
1277 
1278 #ifdef _MODULE
1279 #include "ioconf.c"
1280 #endif
1281 
1282 static int
1283 virtio_pci_modcmd(modcmd_t cmd, void *opaque)
1284 {
1285 	int error = 0;
1286 
1287 #ifdef _MODULE
1288 	switch (cmd) {
1289 	case MODULE_CMD_INIT:
1290 		error = config_init_component(cfdriver_ioconf_virtio_pci,
1291 		    cfattach_ioconf_virtio_pci, cfdata_ioconf_virtio_pci);
1292 		break;
1293 	case MODULE_CMD_FINI:
1294 		error = config_fini_component(cfdriver_ioconf_virtio_pci,
1295 		    cfattach_ioconf_virtio_pci, cfdata_ioconf_virtio_pci);
1296 		break;
1297 	default:
1298 		error = ENOTTY;
1299 		break;
1300 	}
1301 #endif
1302 
1303 	return error;
1304 }
1305