xref: /openbmc/linux/drivers/scsi/fnic/vnic_dev.c (revision b6dcefde)
1 /*
2  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
3  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
4  *
5  * This program is free software; you may redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; version 2 of the License.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
10  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
11  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
12  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
13  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
14  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
15  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
16  * SOFTWARE.
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/errno.h>
21 #include <linux/types.h>
22 #include <linux/pci.h>
23 #include <linux/delay.h>
24 #include <linux/if_ether.h>
25 #include "vnic_resource.h"
26 #include "vnic_devcmd.h"
27 #include "vnic_dev.h"
28 #include "vnic_stats.h"
29 
30 struct vnic_res {
31 	void __iomem *vaddr;
32 	unsigned int count;
33 };
34 
35 struct vnic_dev {
36 	void *priv;
37 	struct pci_dev *pdev;
38 	struct vnic_res res[RES_TYPE_MAX];
39 	enum vnic_dev_intr_mode intr_mode;
40 	struct vnic_devcmd __iomem *devcmd;
41 	struct vnic_devcmd_notify *notify;
42 	struct vnic_devcmd_notify notify_copy;
43 	dma_addr_t notify_pa;
44 	u32 *linkstatus;
45 	dma_addr_t linkstatus_pa;
46 	struct vnic_stats *stats;
47 	dma_addr_t stats_pa;
48 	struct vnic_devcmd_fw_info *fw_info;
49 	dma_addr_t fw_info_pa;
50 };
51 
52 #define VNIC_MAX_RES_HDR_SIZE \
53 	(sizeof(struct vnic_resource_header) + \
54 	sizeof(struct vnic_resource) * RES_TYPE_MAX)
55 #define VNIC_RES_STRIDE	128
56 
57 void *vnic_dev_priv(struct vnic_dev *vdev)
58 {
59 	return vdev->priv;
60 }
61 
62 static int vnic_dev_discover_res(struct vnic_dev *vdev,
63 	struct vnic_dev_bar *bar)
64 {
65 	struct vnic_resource_header __iomem *rh;
66 	struct vnic_resource __iomem *r;
67 	u8 type;
68 
69 	if (bar->len < VNIC_MAX_RES_HDR_SIZE) {
70 		printk(KERN_ERR "vNIC BAR0 res hdr length error\n");
71 		return -EINVAL;
72 	}
73 
74 	rh = bar->vaddr;
75 	if (!rh) {
76 		printk(KERN_ERR "vNIC BAR0 res hdr not mem-mapped\n");
77 		return -EINVAL;
78 	}
79 
80 	if (ioread32(&rh->magic) != VNIC_RES_MAGIC ||
81 	    ioread32(&rh->version) != VNIC_RES_VERSION) {
82 		printk(KERN_ERR "vNIC BAR0 res magic/version error "
83 			"exp (%lx/%lx) curr (%x/%x)\n",
84 			VNIC_RES_MAGIC, VNIC_RES_VERSION,
85 			ioread32(&rh->magic), ioread32(&rh->version));
86 		return -EINVAL;
87 	}
88 
89 	r = (struct vnic_resource __iomem *)(rh + 1);
90 
91 	while ((type = ioread8(&r->type)) != RES_TYPE_EOL) {
92 
93 		u8 bar_num = ioread8(&r->bar);
94 		u32 bar_offset = ioread32(&r->bar_offset);
95 		u32 count = ioread32(&r->count);
96 		u32 len;
97 
98 		r++;
99 
100 		if (bar_num != 0)  /* only mapping in BAR0 resources */
101 			continue;
102 
103 		switch (type) {
104 		case RES_TYPE_WQ:
105 		case RES_TYPE_RQ:
106 		case RES_TYPE_CQ:
107 		case RES_TYPE_INTR_CTRL:
108 			/* each count is stride bytes long */
109 			len = count * VNIC_RES_STRIDE;
110 			if (len + bar_offset > bar->len) {
111 				printk(KERN_ERR "vNIC BAR0 resource %d "
112 					"out-of-bounds, offset 0x%x + "
113 					"size 0x%x > bar len 0x%lx\n",
114 					type, bar_offset,
115 					len,
116 					bar->len);
117 				return -EINVAL;
118 			}
119 			break;
120 		case RES_TYPE_INTR_PBA_LEGACY:
121 		case RES_TYPE_DEVCMD:
122 			len = count;
123 			break;
124 		default:
125 			continue;
126 		}
127 
128 		vdev->res[type].count = count;
129 		vdev->res[type].vaddr = (char __iomem *)bar->vaddr + bar_offset;
130 	}
131 
132 	return 0;
133 }
134 
135 unsigned int vnic_dev_get_res_count(struct vnic_dev *vdev,
136 	enum vnic_res_type type)
137 {
138 	return vdev->res[type].count;
139 }
140 
141 void __iomem *vnic_dev_get_res(struct vnic_dev *vdev, enum vnic_res_type type,
142 	unsigned int index)
143 {
144 	if (!vdev->res[type].vaddr)
145 		return NULL;
146 
147 	switch (type) {
148 	case RES_TYPE_WQ:
149 	case RES_TYPE_RQ:
150 	case RES_TYPE_CQ:
151 	case RES_TYPE_INTR_CTRL:
152 		return (char __iomem *)vdev->res[type].vaddr +
153 					index * VNIC_RES_STRIDE;
154 	default:
155 		return (char __iomem *)vdev->res[type].vaddr;
156 	}
157 }
158 
159 unsigned int vnic_dev_desc_ring_size(struct vnic_dev_ring *ring,
160 				     unsigned int desc_count,
161 				     unsigned int desc_size)
162 {
163 	/* The base address of the desc rings must be 512 byte aligned.
164 	 * Descriptor count is aligned to groups of 32 descriptors.  A
165 	 * count of 0 means the maximum 4096 descriptors.  Descriptor
166 	 * size is aligned to 16 bytes.
167 	 */
168 
169 	unsigned int count_align = 32;
170 	unsigned int desc_align = 16;
171 
172 	ring->base_align = 512;
173 
174 	if (desc_count == 0)
175 		desc_count = 4096;
176 
177 	ring->desc_count = ALIGN(desc_count, count_align);
178 
179 	ring->desc_size = ALIGN(desc_size, desc_align);
180 
181 	ring->size = ring->desc_count * ring->desc_size;
182 	ring->size_unaligned = ring->size + ring->base_align;
183 
184 	return ring->size_unaligned;
185 }
186 
187 void vnic_dev_clear_desc_ring(struct vnic_dev_ring *ring)
188 {
189 	memset(ring->descs, 0, ring->size);
190 }
191 
192 int vnic_dev_alloc_desc_ring(struct vnic_dev *vdev, struct vnic_dev_ring *ring,
193 	unsigned int desc_count, unsigned int desc_size)
194 {
195 	vnic_dev_desc_ring_size(ring, desc_count, desc_size);
196 
197 	ring->descs_unaligned = pci_alloc_consistent(vdev->pdev,
198 		ring->size_unaligned,
199 		&ring->base_addr_unaligned);
200 
201 	if (!ring->descs_unaligned) {
202 		printk(KERN_ERR
203 		  "Failed to allocate ring (size=%d), aborting\n",
204 			(int)ring->size);
205 		return -ENOMEM;
206 	}
207 
208 	ring->base_addr = ALIGN(ring->base_addr_unaligned,
209 		ring->base_align);
210 	ring->descs = (u8 *)ring->descs_unaligned +
211 		(ring->base_addr - ring->base_addr_unaligned);
212 
213 	vnic_dev_clear_desc_ring(ring);
214 
215 	ring->desc_avail = ring->desc_count - 1;
216 
217 	return 0;
218 }
219 
220 void vnic_dev_free_desc_ring(struct vnic_dev *vdev, struct vnic_dev_ring *ring)
221 {
222 	if (ring->descs) {
223 		pci_free_consistent(vdev->pdev,
224 			ring->size_unaligned,
225 			ring->descs_unaligned,
226 			ring->base_addr_unaligned);
227 		ring->descs = NULL;
228 	}
229 }
230 
231 int vnic_dev_cmd(struct vnic_dev *vdev, enum vnic_devcmd_cmd cmd,
232 	u64 *a0, u64 *a1, int wait)
233 {
234 	struct vnic_devcmd __iomem *devcmd = vdev->devcmd;
235 	int delay;
236 	u32 status;
237 	int dev_cmd_err[] = {
238 		/* convert from fw's version of error.h to host's version */
239 		0,	/* ERR_SUCCESS */
240 		EINVAL,	/* ERR_EINVAL */
241 		EFAULT,	/* ERR_EFAULT */
242 		EPERM,	/* ERR_EPERM */
243 		EBUSY,  /* ERR_EBUSY */
244 	};
245 	int err;
246 
247 	status = ioread32(&devcmd->status);
248 	if (status & STAT_BUSY) {
249 		printk(KERN_ERR "Busy devcmd %d\n", _CMD_N(cmd));
250 		return -EBUSY;
251 	}
252 
253 	if (_CMD_DIR(cmd) & _CMD_DIR_WRITE) {
254 		writeq(*a0, &devcmd->args[0]);
255 		writeq(*a1, &devcmd->args[1]);
256 		wmb();
257 	}
258 
259 	iowrite32(cmd, &devcmd->cmd);
260 
261 	if ((_CMD_FLAGS(cmd) & _CMD_FLAGS_NOWAIT))
262 			return 0;
263 
264 	for (delay = 0; delay < wait; delay++) {
265 
266 		udelay(100);
267 
268 		status = ioread32(&devcmd->status);
269 		if (!(status & STAT_BUSY)) {
270 
271 			if (status & STAT_ERROR) {
272 				err = dev_cmd_err[(int)readq(&devcmd->args[0])];
273 				printk(KERN_ERR "Error %d devcmd %d\n",
274 					err, _CMD_N(cmd));
275 				return -err;
276 			}
277 
278 			if (_CMD_DIR(cmd) & _CMD_DIR_READ) {
279 				rmb();
280 				*a0 = readq(&devcmd->args[0]);
281 				*a1 = readq(&devcmd->args[1]);
282 			}
283 
284 			return 0;
285 		}
286 	}
287 
288 	printk(KERN_ERR "Timedout devcmd %d\n", _CMD_N(cmd));
289 	return -ETIMEDOUT;
290 }
291 
292 int vnic_dev_fw_info(struct vnic_dev *vdev,
293 	struct vnic_devcmd_fw_info **fw_info)
294 {
295 	u64 a0, a1 = 0;
296 	int wait = 1000;
297 	int err = 0;
298 
299 	if (!vdev->fw_info) {
300 		vdev->fw_info = pci_alloc_consistent(vdev->pdev,
301 			sizeof(struct vnic_devcmd_fw_info),
302 			&vdev->fw_info_pa);
303 		if (!vdev->fw_info)
304 			return -ENOMEM;
305 
306 		a0 = vdev->fw_info_pa;
307 
308 		/* only get fw_info once and cache it */
309 		err = vnic_dev_cmd(vdev, CMD_MCPU_FW_INFO, &a0, &a1, wait);
310 	}
311 
312 	*fw_info = vdev->fw_info;
313 
314 	return err;
315 }
316 
317 int vnic_dev_spec(struct vnic_dev *vdev, unsigned int offset, unsigned int size,
318 	void *value)
319 {
320 	u64 a0, a1;
321 	int wait = 1000;
322 	int err;
323 
324 	a0 = offset;
325 	a1 = size;
326 
327 	err = vnic_dev_cmd(vdev, CMD_DEV_SPEC, &a0, &a1, wait);
328 
329 	switch (size) {
330 	case 1:
331 		*(u8 *)value = (u8)a0;
332 		break;
333 	case 2:
334 		*(u16 *)value = (u16)a0;
335 		break;
336 	case 4:
337 		*(u32 *)value = (u32)a0;
338 		break;
339 	case 8:
340 		*(u64 *)value = a0;
341 		break;
342 	default:
343 		BUG();
344 		break;
345 	}
346 
347 	return err;
348 }
349 
350 int vnic_dev_stats_clear(struct vnic_dev *vdev)
351 {
352 	u64 a0 = 0, a1 = 0;
353 	int wait = 1000;
354 	return vnic_dev_cmd(vdev, CMD_STATS_CLEAR, &a0, &a1, wait);
355 }
356 
357 int vnic_dev_stats_dump(struct vnic_dev *vdev, struct vnic_stats **stats)
358 {
359 	u64 a0, a1;
360 	int wait = 1000;
361 
362 	if (!vdev->stats) {
363 		vdev->stats = pci_alloc_consistent(vdev->pdev,
364 			sizeof(struct vnic_stats), &vdev->stats_pa);
365 		if (!vdev->stats)
366 			return -ENOMEM;
367 	}
368 
369 	*stats = vdev->stats;
370 	a0 = vdev->stats_pa;
371 	a1 = sizeof(struct vnic_stats);
372 
373 	return vnic_dev_cmd(vdev, CMD_STATS_DUMP, &a0, &a1, wait);
374 }
375 
376 int vnic_dev_close(struct vnic_dev *vdev)
377 {
378 	u64 a0 = 0, a1 = 0;
379 	int wait = 1000;
380 	return vnic_dev_cmd(vdev, CMD_CLOSE, &a0, &a1, wait);
381 }
382 
383 int vnic_dev_enable(struct vnic_dev *vdev)
384 {
385 	u64 a0 = 0, a1 = 0;
386 	int wait = 1000;
387 	return vnic_dev_cmd(vdev, CMD_ENABLE, &a0, &a1, wait);
388 }
389 
390 int vnic_dev_disable(struct vnic_dev *vdev)
391 {
392 	u64 a0 = 0, a1 = 0;
393 	int wait = 1000;
394 	return vnic_dev_cmd(vdev, CMD_DISABLE, &a0, &a1, wait);
395 }
396 
397 int vnic_dev_open(struct vnic_dev *vdev, int arg)
398 {
399 	u64 a0 = (u32)arg, a1 = 0;
400 	int wait = 1000;
401 	return vnic_dev_cmd(vdev, CMD_OPEN, &a0, &a1, wait);
402 }
403 
404 int vnic_dev_open_done(struct vnic_dev *vdev, int *done)
405 {
406 	u64 a0 = 0, a1 = 0;
407 	int wait = 1000;
408 	int err;
409 
410 	*done = 0;
411 
412 	err = vnic_dev_cmd(vdev, CMD_OPEN_STATUS, &a0, &a1, wait);
413 	if (err)
414 		return err;
415 
416 	*done = (a0 == 0);
417 
418 	return 0;
419 }
420 
421 int vnic_dev_soft_reset(struct vnic_dev *vdev, int arg)
422 {
423 	u64 a0 = (u32)arg, a1 = 0;
424 	int wait = 1000;
425 	return vnic_dev_cmd(vdev, CMD_SOFT_RESET, &a0, &a1, wait);
426 }
427 
428 int vnic_dev_soft_reset_done(struct vnic_dev *vdev, int *done)
429 {
430 	u64 a0 = 0, a1 = 0;
431 	int wait = 1000;
432 	int err;
433 
434 	*done = 0;
435 
436 	err = vnic_dev_cmd(vdev, CMD_SOFT_RESET_STATUS, &a0, &a1, wait);
437 	if (err)
438 		return err;
439 
440 	*done = (a0 == 0);
441 
442 	return 0;
443 }
444 
445 int vnic_dev_hang_notify(struct vnic_dev *vdev)
446 {
447 	u64 a0, a1;
448 	int wait = 1000;
449 	return vnic_dev_cmd(vdev, CMD_HANG_NOTIFY, &a0, &a1, wait);
450 }
451 
452 int vnic_dev_mac_addr(struct vnic_dev *vdev, u8 *mac_addr)
453 {
454 	u64 a0, a1;
455 	int wait = 1000;
456 	int err, i;
457 
458 	for (i = 0; i < ETH_ALEN; i++)
459 		mac_addr[i] = 0;
460 
461 	err = vnic_dev_cmd(vdev, CMD_MAC_ADDR, &a0, &a1, wait);
462 	if (err)
463 		return err;
464 
465 	for (i = 0; i < ETH_ALEN; i++)
466 		mac_addr[i] = ((u8 *)&a0)[i];
467 
468 	return 0;
469 }
470 
471 void vnic_dev_packet_filter(struct vnic_dev *vdev, int directed, int multicast,
472 	int broadcast, int promisc, int allmulti)
473 {
474 	u64 a0, a1 = 0;
475 	int wait = 1000;
476 	int err;
477 
478 	a0 = (directed ? CMD_PFILTER_DIRECTED : 0) |
479 	     (multicast ? CMD_PFILTER_MULTICAST : 0) |
480 	     (broadcast ? CMD_PFILTER_BROADCAST : 0) |
481 	     (promisc ? CMD_PFILTER_PROMISCUOUS : 0) |
482 	     (allmulti ? CMD_PFILTER_ALL_MULTICAST : 0);
483 
484 	err = vnic_dev_cmd(vdev, CMD_PACKET_FILTER, &a0, &a1, wait);
485 	if (err)
486 		printk(KERN_ERR "Can't set packet filter\n");
487 }
488 
489 void vnic_dev_add_addr(struct vnic_dev *vdev, u8 *addr)
490 {
491 	u64 a0 = 0, a1 = 0;
492 	int wait = 1000;
493 	int err;
494 	int i;
495 
496 	for (i = 0; i < ETH_ALEN; i++)
497 		((u8 *)&a0)[i] = addr[i];
498 
499 	err = vnic_dev_cmd(vdev, CMD_ADDR_ADD, &a0, &a1, wait);
500 	if (err)
501 		printk(KERN_ERR
502 			"Can't add addr [%02x:%02x:%02x:%02x:%02x:%02x], %d\n",
503 			addr[0], addr[1], addr[2], addr[3], addr[4], addr[5],
504 			err);
505 }
506 
507 void vnic_dev_del_addr(struct vnic_dev *vdev, u8 *addr)
508 {
509 	u64 a0 = 0, a1 = 0;
510 	int wait = 1000;
511 	int err;
512 	int i;
513 
514 	for (i = 0; i < ETH_ALEN; i++)
515 		((u8 *)&a0)[i] = addr[i];
516 
517 	err = vnic_dev_cmd(vdev, CMD_ADDR_DEL, &a0, &a1, wait);
518 	if (err)
519 		printk(KERN_ERR
520 			"Can't del addr [%02x:%02x:%02x:%02x:%02x:%02x], %d\n",
521 			addr[0], addr[1], addr[2], addr[3], addr[4], addr[5],
522 			err);
523 }
524 
525 int vnic_dev_notify_set(struct vnic_dev *vdev, u16 intr)
526 {
527 	u64 a0, a1;
528 	int wait = 1000;
529 
530 	if (!vdev->notify) {
531 		vdev->notify = pci_alloc_consistent(vdev->pdev,
532 			sizeof(struct vnic_devcmd_notify),
533 			&vdev->notify_pa);
534 		if (!vdev->notify)
535 			return -ENOMEM;
536 	}
537 
538 	a0 = vdev->notify_pa;
539 	a1 = ((u64)intr << 32) & 0x0000ffff00000000ULL;
540 	a1 += sizeof(struct vnic_devcmd_notify);
541 
542 	return vnic_dev_cmd(vdev, CMD_NOTIFY, &a0, &a1, wait);
543 }
544 
545 void vnic_dev_notify_unset(struct vnic_dev *vdev)
546 {
547 	u64 a0, a1;
548 	int wait = 1000;
549 
550 	a0 = 0;  /* paddr = 0 to unset notify buffer */
551 	a1 = 0x0000ffff00000000ULL; /* intr num = -1 to unreg for intr */
552 	a1 += sizeof(struct vnic_devcmd_notify);
553 
554 	vnic_dev_cmd(vdev, CMD_NOTIFY, &a0, &a1, wait);
555 }
556 
557 static int vnic_dev_notify_ready(struct vnic_dev *vdev)
558 {
559 	u32 *words;
560 	unsigned int nwords = sizeof(struct vnic_devcmd_notify) / 4;
561 	unsigned int i;
562 	u32 csum;
563 
564 	if (!vdev->notify)
565 		return 0;
566 
567 	do {
568 		csum = 0;
569 		memcpy(&vdev->notify_copy, vdev->notify,
570 			sizeof(struct vnic_devcmd_notify));
571 		words = (u32 *)&vdev->notify_copy;
572 		for (i = 1; i < nwords; i++)
573 			csum += words[i];
574 	} while (csum != words[0]);
575 
576 	return 1;
577 }
578 
579 int vnic_dev_init(struct vnic_dev *vdev, int arg)
580 {
581 	u64 a0 = (u32)arg, a1 = 0;
582 	int wait = 1000;
583 	return vnic_dev_cmd(vdev, CMD_INIT, &a0, &a1, wait);
584 }
585 
586 int vnic_dev_link_status(struct vnic_dev *vdev)
587 {
588 	if (vdev->linkstatus)
589 		return *vdev->linkstatus;
590 
591 	if (!vnic_dev_notify_ready(vdev))
592 		return 0;
593 
594 	return vdev->notify_copy.link_state;
595 }
596 
597 u32 vnic_dev_port_speed(struct vnic_dev *vdev)
598 {
599 	if (!vnic_dev_notify_ready(vdev))
600 		return 0;
601 
602 	return vdev->notify_copy.port_speed;
603 }
604 
605 u32 vnic_dev_msg_lvl(struct vnic_dev *vdev)
606 {
607 	if (!vnic_dev_notify_ready(vdev))
608 		return 0;
609 
610 	return vdev->notify_copy.msglvl;
611 }
612 
613 u32 vnic_dev_mtu(struct vnic_dev *vdev)
614 {
615 	if (!vnic_dev_notify_ready(vdev))
616 		return 0;
617 
618 	return vdev->notify_copy.mtu;
619 }
620 
621 u32 vnic_dev_link_down_cnt(struct vnic_dev *vdev)
622 {
623 	if (!vnic_dev_notify_ready(vdev))
624 		return 0;
625 
626 	return vdev->notify_copy.link_down_cnt;
627 }
628 
629 void vnic_dev_set_intr_mode(struct vnic_dev *vdev,
630 	enum vnic_dev_intr_mode intr_mode)
631 {
632 	vdev->intr_mode = intr_mode;
633 }
634 
635 enum vnic_dev_intr_mode vnic_dev_get_intr_mode(
636 	struct vnic_dev *vdev)
637 {
638 	return vdev->intr_mode;
639 }
640 
641 void vnic_dev_unregister(struct vnic_dev *vdev)
642 {
643 	if (vdev) {
644 		if (vdev->notify)
645 			pci_free_consistent(vdev->pdev,
646 				sizeof(struct vnic_devcmd_notify),
647 				vdev->notify,
648 				vdev->notify_pa);
649 		if (vdev->linkstatus)
650 			pci_free_consistent(vdev->pdev,
651 				sizeof(u32),
652 				vdev->linkstatus,
653 				vdev->linkstatus_pa);
654 		if (vdev->stats)
655 			pci_free_consistent(vdev->pdev,
656 				sizeof(struct vnic_dev),
657 				vdev->stats, vdev->stats_pa);
658 		if (vdev->fw_info)
659 			pci_free_consistent(vdev->pdev,
660 				sizeof(struct vnic_devcmd_fw_info),
661 				vdev->fw_info, vdev->fw_info_pa);
662 		kfree(vdev);
663 	}
664 }
665 
666 struct vnic_dev *vnic_dev_register(struct vnic_dev *vdev,
667 	void *priv, struct pci_dev *pdev, struct vnic_dev_bar *bar)
668 {
669 	if (!vdev) {
670 		vdev = kzalloc(sizeof(struct vnic_dev), GFP_KERNEL);
671 		if (!vdev)
672 			return NULL;
673 	}
674 
675 	vdev->priv = priv;
676 	vdev->pdev = pdev;
677 
678 	if (vnic_dev_discover_res(vdev, bar))
679 		goto err_out;
680 
681 	vdev->devcmd = vnic_dev_get_res(vdev, RES_TYPE_DEVCMD, 0);
682 	if (!vdev->devcmd)
683 		goto err_out;
684 
685 	return vdev;
686 
687 err_out:
688 	vnic_dev_unregister(vdev);
689 	return NULL;
690 }
691