xref: /dpdk/drivers/net/virtio/virtio_pci.c (revision 3998e2a07220844d3f3c17f76a781ced3efe0de0)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4 #include <stdint.h>
5 
6 #ifdef RTE_EXEC_ENV_LINUXAPP
7  #include <dirent.h>
8  #include <fcntl.h>
9 #endif
10 
11 #include <rte_io.h>
12 #include <rte_bus.h>
13 
14 #include "virtio_pci.h"
15 #include "virtio_logs.h"
16 #include "virtqueue.h"
17 
18 /*
19  * Following macros are derived from linux/pci_regs.h, however,
20  * we can't simply include that header here, as there is no such
21  * file for non-Linux platform.
22  */
23 #define PCI_CAPABILITY_LIST	0x34
24 #define PCI_CAP_ID_VNDR		0x09
25 #define PCI_CAP_ID_MSIX		0x11
26 
27 /*
28  * The remaining space is defined by each driver as the per-driver
29  * configuration space.
30  */
31 #define VIRTIO_PCI_CONFIG(hw) \
32 		(((hw)->use_msix == VIRTIO_MSIX_ENABLED) ? 24 : 20)
33 
34 static inline int
35 check_vq_phys_addr_ok(struct virtqueue *vq)
36 {
37 	/* Virtio PCI device VIRTIO_PCI_QUEUE_PF register is 32bit,
38 	 * and only accepts 32 bit page frame number.
39 	 * Check if the allocated physical memory exceeds 16TB.
40 	 */
41 	if ((vq->vq_ring_mem + vq->vq_ring_size - 1) >>
42 			(VIRTIO_PCI_QUEUE_ADDR_SHIFT + 32)) {
43 		PMD_INIT_LOG(ERR, "vring address shouldn't be above 16TB!");
44 		return 0;
45 	}
46 
47 	return 1;
48 }
49 
50 /*
51  * Since we are in legacy mode:
52  * http://ozlabs.org/~rusty/virtio-spec/virtio-0.9.5.pdf
53  *
54  * "Note that this is possible because while the virtio header is PCI (i.e.
55  * little) endian, the device-specific region is encoded in the native endian of
56  * the guest (where such distinction is applicable)."
57  *
58  * For powerpc which supports both, qemu supposes that cpu is big endian and
59  * enforces this for the virtio-net stuff.
60  */
61 static void
62 legacy_read_dev_config(struct virtio_hw *hw, size_t offset,
63 		       void *dst, int length)
64 {
65 #ifdef RTE_ARCH_PPC_64
66 	int size;
67 
68 	while (length > 0) {
69 		if (length >= 4) {
70 			size = 4;
71 			rte_pci_ioport_read(VTPCI_IO(hw), dst, size,
72 				VIRTIO_PCI_CONFIG(hw) + offset);
73 			*(uint32_t *)dst = rte_be_to_cpu_32(*(uint32_t *)dst);
74 		} else if (length >= 2) {
75 			size = 2;
76 			rte_pci_ioport_read(VTPCI_IO(hw), dst, size,
77 				VIRTIO_PCI_CONFIG(hw) + offset);
78 			*(uint16_t *)dst = rte_be_to_cpu_16(*(uint16_t *)dst);
79 		} else {
80 			size = 1;
81 			rte_pci_ioport_read(VTPCI_IO(hw), dst, size,
82 				VIRTIO_PCI_CONFIG(hw) + offset);
83 		}
84 
85 		dst = (char *)dst + size;
86 		offset += size;
87 		length -= size;
88 	}
89 #else
90 	rte_pci_ioport_read(VTPCI_IO(hw), dst, length,
91 		VIRTIO_PCI_CONFIG(hw) + offset);
92 #endif
93 }
94 
95 static void
96 legacy_write_dev_config(struct virtio_hw *hw, size_t offset,
97 			const void *src, int length)
98 {
99 #ifdef RTE_ARCH_PPC_64
100 	union {
101 		uint32_t u32;
102 		uint16_t u16;
103 	} tmp;
104 	int size;
105 
106 	while (length > 0) {
107 		if (length >= 4) {
108 			size = 4;
109 			tmp.u32 = rte_cpu_to_be_32(*(const uint32_t *)src);
110 			rte_pci_ioport_write(VTPCI_IO(hw), &tmp.u32, size,
111 				VIRTIO_PCI_CONFIG(hw) + offset);
112 		} else if (length >= 2) {
113 			size = 2;
114 			tmp.u16 = rte_cpu_to_be_16(*(const uint16_t *)src);
115 			rte_pci_ioport_write(VTPCI_IO(hw), &tmp.u16, size,
116 				VIRTIO_PCI_CONFIG(hw) + offset);
117 		} else {
118 			size = 1;
119 			rte_pci_ioport_write(VTPCI_IO(hw), src, size,
120 				VIRTIO_PCI_CONFIG(hw) + offset);
121 		}
122 
123 		src = (const char *)src + size;
124 		offset += size;
125 		length -= size;
126 	}
127 #else
128 	rte_pci_ioport_write(VTPCI_IO(hw), src, length,
129 		VIRTIO_PCI_CONFIG(hw) + offset);
130 #endif
131 }
132 
133 static uint64_t
134 legacy_get_features(struct virtio_hw *hw)
135 {
136 	uint32_t dst;
137 
138 	rte_pci_ioport_read(VTPCI_IO(hw), &dst, 4, VIRTIO_PCI_HOST_FEATURES);
139 	return dst;
140 }
141 
142 static void
143 legacy_set_features(struct virtio_hw *hw, uint64_t features)
144 {
145 	if ((features >> 32) != 0) {
146 		PMD_DRV_LOG(ERR,
147 			"only 32 bit features are allowed for legacy virtio!");
148 		return;
149 	}
150 	rte_pci_ioport_write(VTPCI_IO(hw), &features, 4,
151 		VIRTIO_PCI_GUEST_FEATURES);
152 }
153 
154 static uint8_t
155 legacy_get_status(struct virtio_hw *hw)
156 {
157 	uint8_t dst;
158 
159 	rte_pci_ioport_read(VTPCI_IO(hw), &dst, 1, VIRTIO_PCI_STATUS);
160 	return dst;
161 }
162 
163 static void
164 legacy_set_status(struct virtio_hw *hw, uint8_t status)
165 {
166 	rte_pci_ioport_write(VTPCI_IO(hw), &status, 1, VIRTIO_PCI_STATUS);
167 }
168 
169 static void
170 legacy_reset(struct virtio_hw *hw)
171 {
172 	legacy_set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
173 }
174 
175 static uint8_t
176 legacy_get_isr(struct virtio_hw *hw)
177 {
178 	uint8_t dst;
179 
180 	rte_pci_ioport_read(VTPCI_IO(hw), &dst, 1, VIRTIO_PCI_ISR);
181 	return dst;
182 }
183 
184 /* Enable one vector (0) for Link State Intrerrupt */
185 static uint16_t
186 legacy_set_config_irq(struct virtio_hw *hw, uint16_t vec)
187 {
188 	uint16_t dst;
189 
190 	rte_pci_ioport_write(VTPCI_IO(hw), &vec, 2, VIRTIO_MSI_CONFIG_VECTOR);
191 	rte_pci_ioport_read(VTPCI_IO(hw), &dst, 2, VIRTIO_MSI_CONFIG_VECTOR);
192 	return dst;
193 }
194 
195 static uint16_t
196 legacy_set_queue_irq(struct virtio_hw *hw, struct virtqueue *vq, uint16_t vec)
197 {
198 	uint16_t dst;
199 
200 	rte_pci_ioport_write(VTPCI_IO(hw), &vq->vq_queue_index, 2,
201 		VIRTIO_PCI_QUEUE_SEL);
202 	rte_pci_ioport_write(VTPCI_IO(hw), &vec, 2, VIRTIO_MSI_QUEUE_VECTOR);
203 	rte_pci_ioport_read(VTPCI_IO(hw), &dst, 2, VIRTIO_MSI_QUEUE_VECTOR);
204 	return dst;
205 }
206 
207 static uint16_t
208 legacy_get_queue_num(struct virtio_hw *hw, uint16_t queue_id)
209 {
210 	uint16_t dst;
211 
212 	rte_pci_ioport_write(VTPCI_IO(hw), &queue_id, 2, VIRTIO_PCI_QUEUE_SEL);
213 	rte_pci_ioport_read(VTPCI_IO(hw), &dst, 2, VIRTIO_PCI_QUEUE_NUM);
214 	return dst;
215 }
216 
217 static int
218 legacy_setup_queue(struct virtio_hw *hw, struct virtqueue *vq)
219 {
220 	uint32_t src;
221 
222 	if (!check_vq_phys_addr_ok(vq))
223 		return -1;
224 
225 	rte_pci_ioport_write(VTPCI_IO(hw), &vq->vq_queue_index, 2,
226 		VIRTIO_PCI_QUEUE_SEL);
227 	src = vq->vq_ring_mem >> VIRTIO_PCI_QUEUE_ADDR_SHIFT;
228 	rte_pci_ioport_write(VTPCI_IO(hw), &src, 4, VIRTIO_PCI_QUEUE_PFN);
229 
230 	return 0;
231 }
232 
233 static void
234 legacy_del_queue(struct virtio_hw *hw, struct virtqueue *vq)
235 {
236 	uint32_t src = 0;
237 
238 	rte_pci_ioport_write(VTPCI_IO(hw), &vq->vq_queue_index, 2,
239 		VIRTIO_PCI_QUEUE_SEL);
240 	rte_pci_ioport_write(VTPCI_IO(hw), &src, 4, VIRTIO_PCI_QUEUE_PFN);
241 }
242 
243 static void
244 legacy_notify_queue(struct virtio_hw *hw, struct virtqueue *vq)
245 {
246 	rte_pci_ioport_write(VTPCI_IO(hw), &vq->vq_queue_index, 2,
247 		VIRTIO_PCI_QUEUE_NOTIFY);
248 }
249 
250 const struct virtio_pci_ops legacy_ops = {
251 	.read_dev_cfg	= legacy_read_dev_config,
252 	.write_dev_cfg	= legacy_write_dev_config,
253 	.reset		= legacy_reset,
254 	.get_status	= legacy_get_status,
255 	.set_status	= legacy_set_status,
256 	.get_features	= legacy_get_features,
257 	.set_features	= legacy_set_features,
258 	.get_isr	= legacy_get_isr,
259 	.set_config_irq	= legacy_set_config_irq,
260 	.set_queue_irq  = legacy_set_queue_irq,
261 	.get_queue_num	= legacy_get_queue_num,
262 	.setup_queue	= legacy_setup_queue,
263 	.del_queue	= legacy_del_queue,
264 	.notify_queue	= legacy_notify_queue,
265 };
266 
267 static inline void
268 io_write64_twopart(uint64_t val, uint32_t *lo, uint32_t *hi)
269 {
270 	rte_write32(val & ((1ULL << 32) - 1), lo);
271 	rte_write32(val >> 32,		     hi);
272 }
273 
274 static void
275 modern_read_dev_config(struct virtio_hw *hw, size_t offset,
276 		       void *dst, int length)
277 {
278 	int i;
279 	uint8_t *p;
280 	uint8_t old_gen, new_gen;
281 
282 	do {
283 		old_gen = rte_read8(&hw->common_cfg->config_generation);
284 
285 		p = dst;
286 		for (i = 0;  i < length; i++)
287 			*p++ = rte_read8((uint8_t *)hw->dev_cfg + offset + i);
288 
289 		new_gen = rte_read8(&hw->common_cfg->config_generation);
290 	} while (old_gen != new_gen);
291 }
292 
293 static void
294 modern_write_dev_config(struct virtio_hw *hw, size_t offset,
295 			const void *src, int length)
296 {
297 	int i;
298 	const uint8_t *p = src;
299 
300 	for (i = 0;  i < length; i++)
301 		rte_write8((*p++), (((uint8_t *)hw->dev_cfg) + offset + i));
302 }
303 
304 static uint64_t
305 modern_get_features(struct virtio_hw *hw)
306 {
307 	uint32_t features_lo, features_hi;
308 
309 	rte_write32(0, &hw->common_cfg->device_feature_select);
310 	features_lo = rte_read32(&hw->common_cfg->device_feature);
311 
312 	rte_write32(1, &hw->common_cfg->device_feature_select);
313 	features_hi = rte_read32(&hw->common_cfg->device_feature);
314 
315 	return ((uint64_t)features_hi << 32) | features_lo;
316 }
317 
318 static void
319 modern_set_features(struct virtio_hw *hw, uint64_t features)
320 {
321 	rte_write32(0, &hw->common_cfg->guest_feature_select);
322 	rte_write32(features & ((1ULL << 32) - 1),
323 		    &hw->common_cfg->guest_feature);
324 
325 	rte_write32(1, &hw->common_cfg->guest_feature_select);
326 	rte_write32(features >> 32,
327 		    &hw->common_cfg->guest_feature);
328 }
329 
330 static uint8_t
331 modern_get_status(struct virtio_hw *hw)
332 {
333 	return rte_read8(&hw->common_cfg->device_status);
334 }
335 
336 static void
337 modern_set_status(struct virtio_hw *hw, uint8_t status)
338 {
339 	rte_write8(status, &hw->common_cfg->device_status);
340 }
341 
342 static void
343 modern_reset(struct virtio_hw *hw)
344 {
345 	modern_set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
346 	modern_get_status(hw);
347 }
348 
349 static uint8_t
350 modern_get_isr(struct virtio_hw *hw)
351 {
352 	return rte_read8(hw->isr);
353 }
354 
355 static uint16_t
356 modern_set_config_irq(struct virtio_hw *hw, uint16_t vec)
357 {
358 	rte_write16(vec, &hw->common_cfg->msix_config);
359 	return rte_read16(&hw->common_cfg->msix_config);
360 }
361 
362 static uint16_t
363 modern_set_queue_irq(struct virtio_hw *hw, struct virtqueue *vq, uint16_t vec)
364 {
365 	rte_write16(vq->vq_queue_index, &hw->common_cfg->queue_select);
366 	rte_write16(vec, &hw->common_cfg->queue_msix_vector);
367 	return rte_read16(&hw->common_cfg->queue_msix_vector);
368 }
369 
370 static uint16_t
371 modern_get_queue_num(struct virtio_hw *hw, uint16_t queue_id)
372 {
373 	rte_write16(queue_id, &hw->common_cfg->queue_select);
374 	return rte_read16(&hw->common_cfg->queue_size);
375 }
376 
377 static int
378 modern_setup_queue(struct virtio_hw *hw, struct virtqueue *vq)
379 {
380 	uint64_t desc_addr, avail_addr, used_addr;
381 	uint16_t notify_off;
382 
383 	if (!check_vq_phys_addr_ok(vq))
384 		return -1;
385 
386 	desc_addr = vq->vq_ring_mem;
387 	avail_addr = desc_addr + vq->vq_nentries * sizeof(struct vring_desc);
388 	used_addr = RTE_ALIGN_CEIL(avail_addr + offsetof(struct vring_avail,
389 							 ring[vq->vq_nentries]),
390 				   VIRTIO_PCI_VRING_ALIGN);
391 
392 	rte_write16(vq->vq_queue_index, &hw->common_cfg->queue_select);
393 
394 	io_write64_twopart(desc_addr, &hw->common_cfg->queue_desc_lo,
395 				      &hw->common_cfg->queue_desc_hi);
396 	io_write64_twopart(avail_addr, &hw->common_cfg->queue_avail_lo,
397 				       &hw->common_cfg->queue_avail_hi);
398 	io_write64_twopart(used_addr, &hw->common_cfg->queue_used_lo,
399 				      &hw->common_cfg->queue_used_hi);
400 
401 	notify_off = rte_read16(&hw->common_cfg->queue_notify_off);
402 	vq->notify_addr = (void *)((uint8_t *)hw->notify_base +
403 				notify_off * hw->notify_off_multiplier);
404 
405 	rte_write16(1, &hw->common_cfg->queue_enable);
406 
407 	PMD_INIT_LOG(DEBUG, "queue %u addresses:", vq->vq_queue_index);
408 	PMD_INIT_LOG(DEBUG, "\t desc_addr: %" PRIx64, desc_addr);
409 	PMD_INIT_LOG(DEBUG, "\t aval_addr: %" PRIx64, avail_addr);
410 	PMD_INIT_LOG(DEBUG, "\t used_addr: %" PRIx64, used_addr);
411 	PMD_INIT_LOG(DEBUG, "\t notify addr: %p (notify offset: %u)",
412 		vq->notify_addr, notify_off);
413 
414 	return 0;
415 }
416 
417 static void
418 modern_del_queue(struct virtio_hw *hw, struct virtqueue *vq)
419 {
420 	rte_write16(vq->vq_queue_index, &hw->common_cfg->queue_select);
421 
422 	io_write64_twopart(0, &hw->common_cfg->queue_desc_lo,
423 				  &hw->common_cfg->queue_desc_hi);
424 	io_write64_twopart(0, &hw->common_cfg->queue_avail_lo,
425 				  &hw->common_cfg->queue_avail_hi);
426 	io_write64_twopart(0, &hw->common_cfg->queue_used_lo,
427 				  &hw->common_cfg->queue_used_hi);
428 
429 	rte_write16(0, &hw->common_cfg->queue_enable);
430 }
431 
432 static void
433 modern_notify_queue(struct virtio_hw *hw __rte_unused, struct virtqueue *vq)
434 {
435 	rte_write16(vq->vq_queue_index, vq->notify_addr);
436 }
437 
438 const struct virtio_pci_ops modern_ops = {
439 	.read_dev_cfg	= modern_read_dev_config,
440 	.write_dev_cfg	= modern_write_dev_config,
441 	.reset		= modern_reset,
442 	.get_status	= modern_get_status,
443 	.set_status	= modern_set_status,
444 	.get_features	= modern_get_features,
445 	.set_features	= modern_set_features,
446 	.get_isr	= modern_get_isr,
447 	.set_config_irq	= modern_set_config_irq,
448 	.set_queue_irq  = modern_set_queue_irq,
449 	.get_queue_num	= modern_get_queue_num,
450 	.setup_queue	= modern_setup_queue,
451 	.del_queue	= modern_del_queue,
452 	.notify_queue	= modern_notify_queue,
453 };
454 
455 
456 void
457 vtpci_read_dev_config(struct virtio_hw *hw, size_t offset,
458 		      void *dst, int length)
459 {
460 	VTPCI_OPS(hw)->read_dev_cfg(hw, offset, dst, length);
461 }
462 
463 void
464 vtpci_write_dev_config(struct virtio_hw *hw, size_t offset,
465 		       const void *src, int length)
466 {
467 	VTPCI_OPS(hw)->write_dev_cfg(hw, offset, src, length);
468 }
469 
470 uint64_t
471 vtpci_negotiate_features(struct virtio_hw *hw, uint64_t host_features)
472 {
473 	uint64_t features;
474 
475 	/*
476 	 * Limit negotiated features to what the driver, virtqueue, and
477 	 * host all support.
478 	 */
479 	features = host_features & hw->guest_features;
480 	VTPCI_OPS(hw)->set_features(hw, features);
481 
482 	return features;
483 }
484 
485 void
486 vtpci_reset(struct virtio_hw *hw)
487 {
488 	VTPCI_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
489 	/* flush status write */
490 	VTPCI_OPS(hw)->get_status(hw);
491 }
492 
493 void
494 vtpci_reinit_complete(struct virtio_hw *hw)
495 {
496 	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_DRIVER_OK);
497 }
498 
499 void
500 vtpci_set_status(struct virtio_hw *hw, uint8_t status)
501 {
502 	if (status != VIRTIO_CONFIG_STATUS_RESET)
503 		status |= VTPCI_OPS(hw)->get_status(hw);
504 
505 	VTPCI_OPS(hw)->set_status(hw, status);
506 }
507 
508 uint8_t
509 vtpci_get_status(struct virtio_hw *hw)
510 {
511 	return VTPCI_OPS(hw)->get_status(hw);
512 }
513 
514 uint8_t
515 vtpci_isr(struct virtio_hw *hw)
516 {
517 	return VTPCI_OPS(hw)->get_isr(hw);
518 }
519 
520 static void *
521 get_cfg_addr(struct rte_pci_device *dev, struct virtio_pci_cap *cap)
522 {
523 	uint8_t  bar    = cap->bar;
524 	uint32_t length = cap->length;
525 	uint32_t offset = cap->offset;
526 	uint8_t *base;
527 
528 	if (bar >= PCI_MAX_RESOURCE) {
529 		PMD_INIT_LOG(ERR, "invalid bar: %u", bar);
530 		return NULL;
531 	}
532 
533 	if (offset + length < offset) {
534 		PMD_INIT_LOG(ERR, "offset(%u) + length(%u) overflows",
535 			offset, length);
536 		return NULL;
537 	}
538 
539 	if (offset + length > dev->mem_resource[bar].len) {
540 		PMD_INIT_LOG(ERR,
541 			"invalid cap: overflows bar space: %u > %" PRIu64,
542 			offset + length, dev->mem_resource[bar].len);
543 		return NULL;
544 	}
545 
546 	base = dev->mem_resource[bar].addr;
547 	if (base == NULL) {
548 		PMD_INIT_LOG(ERR, "bar %u base addr is NULL", bar);
549 		return NULL;
550 	}
551 
552 	return base + offset;
553 }
554 
555 #define PCI_MSIX_ENABLE 0x8000
556 
557 static int
558 virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw)
559 {
560 	uint8_t pos;
561 	struct virtio_pci_cap cap;
562 	int ret;
563 
564 	if (rte_pci_map_device(dev)) {
565 		PMD_INIT_LOG(DEBUG, "failed to map pci device!");
566 		return -1;
567 	}
568 
569 	ret = rte_pci_read_config(dev, &pos, 1, PCI_CAPABILITY_LIST);
570 	if (ret < 0) {
571 		PMD_INIT_LOG(DEBUG, "failed to read pci capability list");
572 		return -1;
573 	}
574 
575 	while (pos) {
576 		ret = rte_pci_read_config(dev, &cap, sizeof(cap), pos);
577 		if (ret < 0) {
578 			PMD_INIT_LOG(ERR,
579 				"failed to read pci cap at pos: %x", pos);
580 			break;
581 		}
582 
583 		if (cap.cap_vndr == PCI_CAP_ID_MSIX) {
584 			/* Transitional devices would also have this capability,
585 			 * that's why we also check if msix is enabled.
586 			 * 1st byte is cap ID; 2nd byte is the position of next
587 			 * cap; next two bytes are the flags.
588 			 */
589 			uint16_t flags = ((uint16_t *)&cap)[1];
590 
591 			if (flags & PCI_MSIX_ENABLE)
592 				hw->use_msix = VIRTIO_MSIX_ENABLED;
593 			else
594 				hw->use_msix = VIRTIO_MSIX_DISABLED;
595 		}
596 
597 		if (cap.cap_vndr != PCI_CAP_ID_VNDR) {
598 			PMD_INIT_LOG(DEBUG,
599 				"[%2x] skipping non VNDR cap id: %02x",
600 				pos, cap.cap_vndr);
601 			goto next;
602 		}
603 
604 		PMD_INIT_LOG(DEBUG,
605 			"[%2x] cfg type: %u, bar: %u, offset: %04x, len: %u",
606 			pos, cap.cfg_type, cap.bar, cap.offset, cap.length);
607 
608 		switch (cap.cfg_type) {
609 		case VIRTIO_PCI_CAP_COMMON_CFG:
610 			hw->common_cfg = get_cfg_addr(dev, &cap);
611 			break;
612 		case VIRTIO_PCI_CAP_NOTIFY_CFG:
613 			rte_pci_read_config(dev, &hw->notify_off_multiplier,
614 					4, pos + sizeof(cap));
615 			hw->notify_base = get_cfg_addr(dev, &cap);
616 			break;
617 		case VIRTIO_PCI_CAP_DEVICE_CFG:
618 			hw->dev_cfg = get_cfg_addr(dev, &cap);
619 			break;
620 		case VIRTIO_PCI_CAP_ISR_CFG:
621 			hw->isr = get_cfg_addr(dev, &cap);
622 			break;
623 		}
624 
625 next:
626 		pos = cap.cap_next;
627 	}
628 
629 	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
630 	    hw->dev_cfg == NULL    || hw->isr == NULL) {
631 		PMD_INIT_LOG(INFO, "no modern virtio pci device found.");
632 		return -1;
633 	}
634 
635 	PMD_INIT_LOG(INFO, "found modern virtio pci device.");
636 
637 	PMD_INIT_LOG(DEBUG, "common cfg mapped at: %p", hw->common_cfg);
638 	PMD_INIT_LOG(DEBUG, "device cfg mapped at: %p", hw->dev_cfg);
639 	PMD_INIT_LOG(DEBUG, "isr cfg mapped at: %p", hw->isr);
640 	PMD_INIT_LOG(DEBUG, "notify base: %p, notify off multiplier: %u",
641 		hw->notify_base, hw->notify_off_multiplier);
642 
643 	return 0;
644 }
645 
646 /*
647  * Return -1:
648  *   if there is error mapping with VFIO/UIO.
649  *   if port map error when driver type is KDRV_NONE.
650  *   if whitelisted but driver type is KDRV_UNKNOWN.
651  * Return 1 if kernel driver is managing the device.
652  * Return 0 on success.
653  */
654 int
655 vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw)
656 {
657 	/*
658 	 * Try if we can succeed reading virtio pci caps, which exists
659 	 * only on modern pci device. If failed, we fallback to legacy
660 	 * virtio handling.
661 	 */
662 	if (virtio_read_caps(dev, hw) == 0) {
663 		PMD_INIT_LOG(INFO, "modern virtio pci detected.");
664 		virtio_hw_internal[hw->port_id].vtpci_ops = &modern_ops;
665 		hw->modern = 1;
666 		return 0;
667 	}
668 
669 	PMD_INIT_LOG(INFO, "trying with legacy virtio pci.");
670 	if (rte_pci_ioport_map(dev, 0, VTPCI_IO(hw)) < 0) {
671 		if (dev->kdrv == RTE_KDRV_UNKNOWN &&
672 		    (!dev->device.devargs ||
673 		     dev->device.devargs->bus !=
674 		     rte_bus_find_by_name("pci"))) {
675 			PMD_INIT_LOG(INFO,
676 				"skip kernel managed virtio device.");
677 			return 1;
678 		}
679 		return -1;
680 	}
681 
682 	virtio_hw_internal[hw->port_id].vtpci_ops = &legacy_ops;
683 	hw->modern   = 0;
684 
685 	return 0;
686 }
687 
688 enum virtio_msix_status
689 vtpci_msix_detect(struct rte_pci_device *dev)
690 {
691 	uint8_t pos;
692 	struct virtio_pci_cap cap;
693 	int ret;
694 
695 	ret = rte_pci_read_config(dev, &pos, 1, PCI_CAPABILITY_LIST);
696 	if (ret < 0) {
697 		PMD_INIT_LOG(DEBUG, "failed to read pci capability list");
698 		return VIRTIO_MSIX_NONE;
699 	}
700 
701 	while (pos) {
702 		ret = rte_pci_read_config(dev, &cap, sizeof(cap), pos);
703 		if (ret < 0) {
704 			PMD_INIT_LOG(ERR,
705 				"failed to read pci cap at pos: %x", pos);
706 			break;
707 		}
708 
709 		if (cap.cap_vndr == PCI_CAP_ID_MSIX) {
710 			uint16_t flags = ((uint16_t *)&cap)[1];
711 
712 			if (flags & PCI_MSIX_ENABLE)
713 				return VIRTIO_MSIX_ENABLED;
714 			else
715 				return VIRTIO_MSIX_DISABLED;
716 		}
717 
718 		pos = cap.cap_next;
719 	}
720 
721 	return VIRTIO_MSIX_NONE;
722 }
723