xref: /openbmc/linux/drivers/infiniband/hw/hfi1/driver.c (revision 9c6d26df1fae6ad4718d51c48e6517913304ed27)
1 /*
2  * Copyright(c) 2015-2017 Intel Corporation.
3  *
4  * This file is provided under a dual BSD/GPLv2 license.  When using or
5  * redistributing this file, you may do so under either license.
6  *
7  * GPL LICENSE SUMMARY
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * BSD LICENSE
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  *
24  *  - Redistributions of source code must retain the above copyright
25  *    notice, this list of conditions and the following disclaimer.
26  *  - Redistributions in binary form must reproduce the above copyright
27  *    notice, this list of conditions and the following disclaimer in
28  *    the documentation and/or other materials provided with the
29  *    distribution.
30  *  - Neither the name of Intel Corporation nor the names of its
31  *    contributors may be used to endorse or promote products derived
32  *    from this software without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45  *
46  */
47 
48 #include <linux/spinlock.h>
49 #include <linux/pci.h>
50 #include <linux/io.h>
51 #include <linux/delay.h>
52 #include <linux/netdevice.h>
53 #include <linux/vmalloc.h>
54 #include <linux/module.h>
55 #include <linux/prefetch.h>
56 #include <rdma/ib_verbs.h>
57 
58 #include "hfi.h"
59 #include "trace.h"
60 #include "qp.h"
61 #include "sdma.h"
62 #include "debugfs.h"
63 #include "vnic.h"
64 
65 #undef pr_fmt
66 #define pr_fmt(fmt) DRIVER_NAME ": " fmt
67 
68 /*
69  * The size has to be longer than this string, so we can append
70  * board/chip information to it in the initialization code.
71  */
72 const char ib_hfi1_version[] = HFI1_DRIVER_VERSION "\n";
73 
74 DEFINE_SPINLOCK(hfi1_devs_lock);
75 LIST_HEAD(hfi1_dev_list);
76 DEFINE_MUTEX(hfi1_mutex);	/* general driver use */
77 
78 unsigned int hfi1_max_mtu = HFI1_DEFAULT_MAX_MTU;
79 module_param_named(max_mtu, hfi1_max_mtu, uint, S_IRUGO);
80 MODULE_PARM_DESC(max_mtu, "Set max MTU bytes, default is " __stringify(
81 		 HFI1_DEFAULT_MAX_MTU));
82 
83 unsigned int hfi1_cu = 1;
84 module_param_named(cu, hfi1_cu, uint, S_IRUGO);
85 MODULE_PARM_DESC(cu, "Credit return units");
86 
87 unsigned long hfi1_cap_mask = HFI1_CAP_MASK_DEFAULT;
88 static int hfi1_caps_set(const char *val, const struct kernel_param *kp);
89 static int hfi1_caps_get(char *buffer, const struct kernel_param *kp);
90 static const struct kernel_param_ops cap_ops = {
91 	.set = hfi1_caps_set,
92 	.get = hfi1_caps_get
93 };
94 module_param_cb(cap_mask, &cap_ops, &hfi1_cap_mask, S_IWUSR | S_IRUGO);
95 MODULE_PARM_DESC(cap_mask, "Bit mask of enabled/disabled HW features");
96 
97 MODULE_LICENSE("Dual BSD/GPL");
98 MODULE_DESCRIPTION("Intel Omni-Path Architecture driver");
99 
100 /*
101  * MAX_PKT_RCV is the max # if packets processed per receive interrupt.
102  */
103 #define MAX_PKT_RECV 64
104 /*
105  * MAX_PKT_THREAD_RCV is the max # of packets processed before
106  * the qp_wait_list queue is flushed.
107  */
108 #define MAX_PKT_RECV_THREAD (MAX_PKT_RECV * 4)
109 #define EGR_HEAD_UPDATE_THRESHOLD 16
110 
111 struct hfi1_ib_stats hfi1_stats;
112 
113 static int hfi1_caps_set(const char *val, const struct kernel_param *kp)
114 {
115 	int ret = 0;
116 	unsigned long *cap_mask_ptr = (unsigned long *)kp->arg,
117 		cap_mask = *cap_mask_ptr, value, diff,
118 		write_mask = ((HFI1_CAP_WRITABLE_MASK << HFI1_CAP_USER_SHIFT) |
119 			      HFI1_CAP_WRITABLE_MASK);
120 
121 	ret = kstrtoul(val, 0, &value);
122 	if (ret) {
123 		pr_warn("Invalid module parameter value for 'cap_mask'\n");
124 		goto done;
125 	}
126 	/* Get the changed bits (except the locked bit) */
127 	diff = value ^ (cap_mask & ~HFI1_CAP_LOCKED_SMASK);
128 
129 	/* Remove any bits that are not allowed to change after driver load */
130 	if (HFI1_CAP_LOCKED() && (diff & ~write_mask)) {
131 		pr_warn("Ignoring non-writable capability bits %#lx\n",
132 			diff & ~write_mask);
133 		diff &= write_mask;
134 	}
135 
136 	/* Mask off any reserved bits */
137 	diff &= ~HFI1_CAP_RESERVED_MASK;
138 	/* Clear any previously set and changing bits */
139 	cap_mask &= ~diff;
140 	/* Update the bits with the new capability */
141 	cap_mask |= (value & diff);
142 	/* Check for any kernel/user restrictions */
143 	diff = (cap_mask & (HFI1_CAP_MUST_HAVE_KERN << HFI1_CAP_USER_SHIFT)) ^
144 		((cap_mask & HFI1_CAP_MUST_HAVE_KERN) << HFI1_CAP_USER_SHIFT);
145 	cap_mask &= ~diff;
146 	/* Set the bitmask to the final set */
147 	*cap_mask_ptr = cap_mask;
148 done:
149 	return ret;
150 }
151 
152 static int hfi1_caps_get(char *buffer, const struct kernel_param *kp)
153 {
154 	unsigned long cap_mask = *(unsigned long *)kp->arg;
155 
156 	cap_mask &= ~HFI1_CAP_LOCKED_SMASK;
157 	cap_mask |= ((cap_mask & HFI1_CAP_K2U) << HFI1_CAP_USER_SHIFT);
158 
159 	return scnprintf(buffer, PAGE_SIZE, "0x%lx", cap_mask);
160 }
161 
162 struct pci_dev *get_pci_dev(struct rvt_dev_info *rdi)
163 {
164 	struct hfi1_ibdev *ibdev = container_of(rdi, struct hfi1_ibdev, rdi);
165 	struct hfi1_devdata *dd = container_of(ibdev,
166 					       struct hfi1_devdata, verbs_dev);
167 	return dd->pcidev;
168 }
169 
170 /*
171  * Return count of units with at least one port ACTIVE.
172  */
173 int hfi1_count_active_units(void)
174 {
175 	struct hfi1_devdata *dd;
176 	struct hfi1_pportdata *ppd;
177 	unsigned long flags;
178 	int pidx, nunits_active = 0;
179 
180 	spin_lock_irqsave(&hfi1_devs_lock, flags);
181 	list_for_each_entry(dd, &hfi1_dev_list, list) {
182 		if (!(dd->flags & HFI1_PRESENT) || !dd->kregbase1)
183 			continue;
184 		for (pidx = 0; pidx < dd->num_pports; ++pidx) {
185 			ppd = dd->pport + pidx;
186 			if (ppd->lid && ppd->linkup) {
187 				nunits_active++;
188 				break;
189 			}
190 		}
191 	}
192 	spin_unlock_irqrestore(&hfi1_devs_lock, flags);
193 	return nunits_active;
194 }
195 
196 /*
197  * Get address of eager buffer from it's index (allocated in chunks, not
198  * contiguous).
199  */
200 static inline void *get_egrbuf(const struct hfi1_ctxtdata *rcd, u64 rhf,
201 			       u8 *update)
202 {
203 	u32 idx = rhf_egr_index(rhf), offset = rhf_egr_buf_offset(rhf);
204 
205 	*update |= !(idx & (rcd->egrbufs.threshold - 1)) && !offset;
206 	return (void *)(((u64)(rcd->egrbufs.rcvtids[idx].addr)) +
207 			(offset * RCV_BUF_BLOCK_SIZE));
208 }
209 
210 static inline void *hfi1_get_header(struct hfi1_devdata *dd,
211 				    __le32 *rhf_addr)
212 {
213 	u32 offset = rhf_hdrq_offset(rhf_to_cpu(rhf_addr));
214 
215 	return (void *)(rhf_addr - dd->rhf_offset + offset);
216 }
217 
218 static inline struct ib_header *hfi1_get_msgheader(struct hfi1_devdata *dd,
219 						   __le32 *rhf_addr)
220 {
221 	return (struct ib_header *)hfi1_get_header(dd, rhf_addr);
222 }
223 
224 static inline struct hfi1_16b_header
225 		*hfi1_get_16B_header(struct hfi1_devdata *dd,
226 				     __le32 *rhf_addr)
227 {
228 	return (struct hfi1_16b_header *)hfi1_get_header(dd, rhf_addr);
229 }
230 
231 /*
232  * Validate and encode the a given RcvArray Buffer size.
233  * The function will check whether the given size falls within
234  * allowed size ranges for the respective type and, optionally,
235  * return the proper encoding.
236  */
237 int hfi1_rcvbuf_validate(u32 size, u8 type, u16 *encoded)
238 {
239 	if (unlikely(!PAGE_ALIGNED(size)))
240 		return 0;
241 	if (unlikely(size < MIN_EAGER_BUFFER))
242 		return 0;
243 	if (size >
244 	    (type == PT_EAGER ? MAX_EAGER_BUFFER : MAX_EXPECTED_BUFFER))
245 		return 0;
246 	if (encoded)
247 		*encoded = ilog2(size / PAGE_SIZE) + 1;
248 	return 1;
249 }
250 
251 static void rcv_hdrerr(struct hfi1_ctxtdata *rcd, struct hfi1_pportdata *ppd,
252 		       struct hfi1_packet *packet)
253 {
254 	struct ib_header *rhdr = packet->hdr;
255 	u32 rte = rhf_rcv_type_err(packet->rhf);
256 	u32 mlid_base;
257 	struct hfi1_ibport *ibp = rcd_to_iport(rcd);
258 	struct hfi1_devdata *dd = ppd->dd;
259 	struct hfi1_ibdev *verbs_dev = &dd->verbs_dev;
260 	struct rvt_dev_info *rdi = &verbs_dev->rdi;
261 
262 	if ((packet->rhf & RHF_DC_ERR) &&
263 	    hfi1_dbg_fault_suppress_err(verbs_dev))
264 		return;
265 
266 	if (packet->rhf & (RHF_VCRC_ERR | RHF_ICRC_ERR))
267 		return;
268 
269 	if (packet->etype == RHF_RCV_TYPE_BYPASS) {
270 		goto drop;
271 	} else {
272 		u8 lnh = ib_get_lnh(rhdr);
273 
274 		mlid_base = be16_to_cpu(IB_MULTICAST_LID_BASE);
275 		if (lnh == HFI1_LRH_BTH) {
276 			packet->ohdr = &rhdr->u.oth;
277 		} else if (lnh == HFI1_LRH_GRH) {
278 			packet->ohdr = &rhdr->u.l.oth;
279 			packet->grh = &rhdr->u.l.grh;
280 		} else {
281 			goto drop;
282 		}
283 	}
284 
285 	if (packet->rhf & RHF_TID_ERR) {
286 		/* For TIDERR and RC QPs preemptively schedule a NAK */
287 		u32 tlen = rhf_pkt_len(packet->rhf); /* in bytes */
288 		u32 dlid = ib_get_dlid(rhdr);
289 		u32 qp_num;
290 
291 		/* Sanity check packet */
292 		if (tlen < 24)
293 			goto drop;
294 
295 		/* Check for GRH */
296 		if (packet->grh) {
297 			u32 vtf;
298 			struct ib_grh *grh = packet->grh;
299 
300 			if (grh->next_hdr != IB_GRH_NEXT_HDR)
301 				goto drop;
302 			vtf = be32_to_cpu(grh->version_tclass_flow);
303 			if ((vtf >> IB_GRH_VERSION_SHIFT) != IB_GRH_VERSION)
304 				goto drop;
305 		}
306 
307 		/* Get the destination QP number. */
308 		qp_num = ib_bth_get_qpn(packet->ohdr);
309 		if (dlid < mlid_base) {
310 			struct rvt_qp *qp;
311 			unsigned long flags;
312 
313 			rcu_read_lock();
314 			qp = rvt_lookup_qpn(rdi, &ibp->rvp, qp_num);
315 			if (!qp) {
316 				rcu_read_unlock();
317 				goto drop;
318 			}
319 
320 			/*
321 			 * Handle only RC QPs - for other QP types drop error
322 			 * packet.
323 			 */
324 			spin_lock_irqsave(&qp->r_lock, flags);
325 
326 			/* Check for valid receive state. */
327 			if (!(ib_rvt_state_ops[qp->state] &
328 			      RVT_PROCESS_RECV_OK)) {
329 				ibp->rvp.n_pkt_drops++;
330 			}
331 
332 			switch (qp->ibqp.qp_type) {
333 			case IB_QPT_RC:
334 				hfi1_rc_hdrerr(rcd, packet, qp);
335 				break;
336 			default:
337 				/* For now don't handle any other QP types */
338 				break;
339 			}
340 
341 			spin_unlock_irqrestore(&qp->r_lock, flags);
342 			rcu_read_unlock();
343 		} /* Unicast QP */
344 	} /* Valid packet with TIDErr */
345 
346 	/* handle "RcvTypeErr" flags */
347 	switch (rte) {
348 	case RHF_RTE_ERROR_OP_CODE_ERR:
349 	{
350 		void *ebuf = NULL;
351 		u8 opcode;
352 
353 		if (rhf_use_egr_bfr(packet->rhf))
354 			ebuf = packet->ebuf;
355 
356 		if (!ebuf)
357 			goto drop; /* this should never happen */
358 
359 		opcode = ib_bth_get_opcode(packet->ohdr);
360 		if (opcode == IB_OPCODE_CNP) {
361 			/*
362 			 * Only in pre-B0 h/w is the CNP_OPCODE handled
363 			 * via this code path.
364 			 */
365 			struct rvt_qp *qp = NULL;
366 			u32 lqpn, rqpn;
367 			u16 rlid;
368 			u8 svc_type, sl, sc5;
369 
370 			sc5 = hfi1_9B_get_sc5(rhdr, packet->rhf);
371 			sl = ibp->sc_to_sl[sc5];
372 
373 			lqpn = ib_bth_get_qpn(packet->ohdr);
374 			rcu_read_lock();
375 			qp = rvt_lookup_qpn(rdi, &ibp->rvp, lqpn);
376 			if (!qp) {
377 				rcu_read_unlock();
378 				goto drop;
379 			}
380 
381 			switch (qp->ibqp.qp_type) {
382 			case IB_QPT_UD:
383 				rlid = 0;
384 				rqpn = 0;
385 				svc_type = IB_CC_SVCTYPE_UD;
386 				break;
387 			case IB_QPT_UC:
388 				rlid = ib_get_slid(rhdr);
389 				rqpn = qp->remote_qpn;
390 				svc_type = IB_CC_SVCTYPE_UC;
391 				break;
392 			default:
393 				rcu_read_unlock();
394 				goto drop;
395 			}
396 
397 			process_becn(ppd, sl, rlid, lqpn, rqpn, svc_type);
398 			rcu_read_unlock();
399 		}
400 
401 		packet->rhf &= ~RHF_RCV_TYPE_ERR_SMASK;
402 		break;
403 	}
404 	default:
405 		break;
406 	}
407 
408 drop:
409 	return;
410 }
411 
412 static inline void init_packet(struct hfi1_ctxtdata *rcd,
413 			       struct hfi1_packet *packet)
414 {
415 	packet->rsize = rcd->rcvhdrqentsize; /* words */
416 	packet->maxcnt = rcd->rcvhdrq_cnt * packet->rsize; /* words */
417 	packet->rcd = rcd;
418 	packet->updegr = 0;
419 	packet->etail = -1;
420 	packet->rhf_addr = get_rhf_addr(rcd);
421 	packet->rhf = rhf_to_cpu(packet->rhf_addr);
422 	packet->rhqoff = rcd->head;
423 	packet->numpkt = 0;
424 }
425 
426 /* We support only two types - 9B and 16B for now */
427 static const hfi1_handle_cnp hfi1_handle_cnp_tbl[2] = {
428 	[HFI1_PKT_TYPE_9B] = &return_cnp,
429 	[HFI1_PKT_TYPE_16B] = &return_cnp_16B
430 };
431 
432 void hfi1_process_ecn_slowpath(struct rvt_qp *qp, struct hfi1_packet *pkt,
433 			       bool do_cnp)
434 {
435 	struct hfi1_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
436 	struct ib_other_headers *ohdr = pkt->ohdr;
437 	struct ib_grh *grh = pkt->grh;
438 	u32 rqpn = 0, bth1;
439 	u16 pkey, rlid, dlid = ib_get_dlid(pkt->hdr);
440 	u8 hdr_type, sc, svc_type;
441 	bool is_mcast = false;
442 
443 	if (pkt->etype == RHF_RCV_TYPE_BYPASS) {
444 		is_mcast = hfi1_is_16B_mcast(dlid);
445 		pkey = hfi1_16B_get_pkey(pkt->hdr);
446 		sc = hfi1_16B_get_sc(pkt->hdr);
447 		hdr_type = HFI1_PKT_TYPE_16B;
448 	} else {
449 		is_mcast = (dlid > be16_to_cpu(IB_MULTICAST_LID_BASE)) &&
450 			   (dlid != be16_to_cpu(IB_LID_PERMISSIVE));
451 		pkey = ib_bth_get_pkey(ohdr);
452 		sc = hfi1_9B_get_sc5(pkt->hdr, pkt->rhf);
453 		hdr_type = HFI1_PKT_TYPE_9B;
454 	}
455 
456 	switch (qp->ibqp.qp_type) {
457 	case IB_QPT_SMI:
458 	case IB_QPT_GSI:
459 	case IB_QPT_UD:
460 		rlid = ib_get_slid(pkt->hdr);
461 		rqpn = ib_get_sqpn(pkt->ohdr);
462 		svc_type = IB_CC_SVCTYPE_UD;
463 		break;
464 	case IB_QPT_UC:
465 		rlid = rdma_ah_get_dlid(&qp->remote_ah_attr);
466 		rqpn = qp->remote_qpn;
467 		svc_type = IB_CC_SVCTYPE_UC;
468 		break;
469 	case IB_QPT_RC:
470 		rlid = rdma_ah_get_dlid(&qp->remote_ah_attr);
471 		rqpn = qp->remote_qpn;
472 		svc_type = IB_CC_SVCTYPE_RC;
473 		break;
474 	default:
475 		return;
476 	}
477 
478 	bth1 = be32_to_cpu(ohdr->bth[1]);
479 	/* Call appropriate CNP handler */
480 	if (do_cnp && (bth1 & IB_FECN_SMASK))
481 		hfi1_handle_cnp_tbl[hdr_type](ibp, qp, rqpn, pkey,
482 					      dlid, rlid, sc, grh);
483 
484 	if (!is_mcast && (bth1 & IB_BECN_SMASK)) {
485 		struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
486 		u32 lqpn = bth1 & RVT_QPN_MASK;
487 		u8 sl = ibp->sc_to_sl[sc];
488 
489 		process_becn(ppd, sl, rlid, lqpn, rqpn, svc_type);
490 	}
491 
492 }
493 
494 struct ps_mdata {
495 	struct hfi1_ctxtdata *rcd;
496 	u32 rsize;
497 	u32 maxcnt;
498 	u32 ps_head;
499 	u32 ps_tail;
500 	u32 ps_seq;
501 };
502 
503 static inline void init_ps_mdata(struct ps_mdata *mdata,
504 				 struct hfi1_packet *packet)
505 {
506 	struct hfi1_ctxtdata *rcd = packet->rcd;
507 
508 	mdata->rcd = rcd;
509 	mdata->rsize = packet->rsize;
510 	mdata->maxcnt = packet->maxcnt;
511 	mdata->ps_head = packet->rhqoff;
512 
513 	if (HFI1_CAP_KGET_MASK(rcd->flags, DMA_RTAIL)) {
514 		mdata->ps_tail = get_rcvhdrtail(rcd);
515 		if (rcd->ctxt == HFI1_CTRL_CTXT)
516 			mdata->ps_seq = rcd->seq_cnt;
517 		else
518 			mdata->ps_seq = 0; /* not used with DMA_RTAIL */
519 	} else {
520 		mdata->ps_tail = 0; /* used only with DMA_RTAIL*/
521 		mdata->ps_seq = rcd->seq_cnt;
522 	}
523 }
524 
525 static inline int ps_done(struct ps_mdata *mdata, u64 rhf,
526 			  struct hfi1_ctxtdata *rcd)
527 {
528 	if (HFI1_CAP_KGET_MASK(rcd->flags, DMA_RTAIL))
529 		return mdata->ps_head == mdata->ps_tail;
530 	return mdata->ps_seq != rhf_rcv_seq(rhf);
531 }
532 
533 static inline int ps_skip(struct ps_mdata *mdata, u64 rhf,
534 			  struct hfi1_ctxtdata *rcd)
535 {
536 	/*
537 	 * Control context can potentially receive an invalid rhf.
538 	 * Drop such packets.
539 	 */
540 	if ((rcd->ctxt == HFI1_CTRL_CTXT) && (mdata->ps_head != mdata->ps_tail))
541 		return mdata->ps_seq != rhf_rcv_seq(rhf);
542 
543 	return 0;
544 }
545 
546 static inline void update_ps_mdata(struct ps_mdata *mdata,
547 				   struct hfi1_ctxtdata *rcd)
548 {
549 	mdata->ps_head += mdata->rsize;
550 	if (mdata->ps_head >= mdata->maxcnt)
551 		mdata->ps_head = 0;
552 
553 	/* Control context must do seq counting */
554 	if (!HFI1_CAP_KGET_MASK(rcd->flags, DMA_RTAIL) ||
555 	    (rcd->ctxt == HFI1_CTRL_CTXT)) {
556 		if (++mdata->ps_seq > 13)
557 			mdata->ps_seq = 1;
558 	}
559 }
560 
561 /*
562  * prescan_rxq - search through the receive queue looking for packets
563  * containing Excplicit Congestion Notifications (FECNs, or BECNs).
564  * When an ECN is found, process the Congestion Notification, and toggle
565  * it off.
566  * This is declared as a macro to allow quick checking of the port to avoid
567  * the overhead of a function call if not enabled.
568  */
569 #define prescan_rxq(rcd, packet) \
570 	do { \
571 		if (rcd->ppd->cc_prescan) \
572 			__prescan_rxq(packet); \
573 	} while (0)
574 static void __prescan_rxq(struct hfi1_packet *packet)
575 {
576 	struct hfi1_ctxtdata *rcd = packet->rcd;
577 	struct ps_mdata mdata;
578 
579 	init_ps_mdata(&mdata, packet);
580 
581 	while (1) {
582 		struct hfi1_devdata *dd = rcd->dd;
583 		struct hfi1_ibport *ibp = rcd_to_iport(rcd);
584 		__le32 *rhf_addr = (__le32 *)rcd->rcvhdrq + mdata.ps_head +
585 					 dd->rhf_offset;
586 		struct rvt_qp *qp;
587 		struct ib_header *hdr;
588 		struct rvt_dev_info *rdi = &dd->verbs_dev.rdi;
589 		u64 rhf = rhf_to_cpu(rhf_addr);
590 		u32 etype = rhf_rcv_type(rhf), qpn, bth1;
591 		int is_ecn = 0;
592 		u8 lnh;
593 
594 		if (ps_done(&mdata, rhf, rcd))
595 			break;
596 
597 		if (ps_skip(&mdata, rhf, rcd))
598 			goto next;
599 
600 		if (etype != RHF_RCV_TYPE_IB)
601 			goto next;
602 
603 		packet->hdr = hfi1_get_msgheader(dd, rhf_addr);
604 		hdr = packet->hdr;
605 		lnh = ib_get_lnh(hdr);
606 
607 		if (lnh == HFI1_LRH_BTH) {
608 			packet->ohdr = &hdr->u.oth;
609 			packet->grh = NULL;
610 		} else if (lnh == HFI1_LRH_GRH) {
611 			packet->ohdr = &hdr->u.l.oth;
612 			packet->grh = &hdr->u.l.grh;
613 		} else {
614 			goto next; /* just in case */
615 		}
616 
617 		bth1 = be32_to_cpu(packet->ohdr->bth[1]);
618 		is_ecn = !!(bth1 & (IB_FECN_SMASK | IB_BECN_SMASK));
619 
620 		if (!is_ecn)
621 			goto next;
622 
623 		qpn = bth1 & RVT_QPN_MASK;
624 		rcu_read_lock();
625 		qp = rvt_lookup_qpn(rdi, &ibp->rvp, qpn);
626 
627 		if (!qp) {
628 			rcu_read_unlock();
629 			goto next;
630 		}
631 
632 		process_ecn(qp, packet, true);
633 		rcu_read_unlock();
634 
635 		/* turn off BECN, FECN */
636 		bth1 &= ~(IB_FECN_SMASK | IB_BECN_SMASK);
637 		packet->ohdr->bth[1] = cpu_to_be32(bth1);
638 next:
639 		update_ps_mdata(&mdata, rcd);
640 	}
641 }
642 
643 static void process_rcv_qp_work(struct hfi1_packet *packet)
644 {
645 	struct rvt_qp *qp, *nqp;
646 	struct hfi1_ctxtdata *rcd = packet->rcd;
647 
648 	/*
649 	 * Iterate over all QPs waiting to respond.
650 	 * The list won't change since the IRQ is only run on one CPU.
651 	 */
652 	list_for_each_entry_safe(qp, nqp, &rcd->qp_wait_list, rspwait) {
653 		list_del_init(&qp->rspwait);
654 		if (qp->r_flags & RVT_R_RSP_NAK) {
655 			qp->r_flags &= ~RVT_R_RSP_NAK;
656 			packet->qp = qp;
657 			hfi1_send_rc_ack(packet, 0);
658 		}
659 		if (qp->r_flags & RVT_R_RSP_SEND) {
660 			unsigned long flags;
661 
662 			qp->r_flags &= ~RVT_R_RSP_SEND;
663 			spin_lock_irqsave(&qp->s_lock, flags);
664 			if (ib_rvt_state_ops[qp->state] &
665 					RVT_PROCESS_OR_FLUSH_SEND)
666 				hfi1_schedule_send(qp);
667 			spin_unlock_irqrestore(&qp->s_lock, flags);
668 		}
669 		rvt_put_qp(qp);
670 	}
671 }
672 
673 static noinline int max_packet_exceeded(struct hfi1_packet *packet, int thread)
674 {
675 	if (thread) {
676 		if ((packet->numpkt & (MAX_PKT_RECV_THREAD - 1)) == 0)
677 			/* allow defered processing */
678 			process_rcv_qp_work(packet);
679 		cond_resched();
680 		return RCV_PKT_OK;
681 	} else {
682 		this_cpu_inc(*packet->rcd->dd->rcv_limit);
683 		return RCV_PKT_LIMIT;
684 	}
685 }
686 
687 static inline int check_max_packet(struct hfi1_packet *packet, int thread)
688 {
689 	int ret = RCV_PKT_OK;
690 
691 	if (unlikely((packet->numpkt & (MAX_PKT_RECV - 1)) == 0))
692 		ret = max_packet_exceeded(packet, thread);
693 	return ret;
694 }
695 
696 static noinline int skip_rcv_packet(struct hfi1_packet *packet, int thread)
697 {
698 	int ret;
699 
700 	/* Set up for the next packet */
701 	packet->rhqoff += packet->rsize;
702 	if (packet->rhqoff >= packet->maxcnt)
703 		packet->rhqoff = 0;
704 
705 	packet->numpkt++;
706 	ret = check_max_packet(packet, thread);
707 
708 	packet->rhf_addr = (__le32 *)packet->rcd->rcvhdrq + packet->rhqoff +
709 				     packet->rcd->dd->rhf_offset;
710 	packet->rhf = rhf_to_cpu(packet->rhf_addr);
711 
712 	return ret;
713 }
714 
715 static inline int process_rcv_packet(struct hfi1_packet *packet, int thread)
716 {
717 	int ret;
718 
719 	packet->etype = rhf_rcv_type(packet->rhf);
720 
721 	/* total length */
722 	packet->tlen = rhf_pkt_len(packet->rhf); /* in bytes */
723 	/* retrieve eager buffer details */
724 	packet->ebuf = NULL;
725 	if (rhf_use_egr_bfr(packet->rhf)) {
726 		packet->etail = rhf_egr_index(packet->rhf);
727 		packet->ebuf = get_egrbuf(packet->rcd, packet->rhf,
728 				 &packet->updegr);
729 		/*
730 		 * Prefetch the contents of the eager buffer.  It is
731 		 * OK to send a negative length to prefetch_range().
732 		 * The +2 is the size of the RHF.
733 		 */
734 		prefetch_range(packet->ebuf,
735 			       packet->tlen - ((packet->rcd->rcvhdrqentsize -
736 					       (rhf_hdrq_offset(packet->rhf)
737 						+ 2)) * 4));
738 	}
739 
740 	/*
741 	 * Call a type specific handler for the packet. We
742 	 * should be able to trust that etype won't be beyond
743 	 * the range of valid indexes. If so something is really
744 	 * wrong and we can probably just let things come
745 	 * crashing down. There is no need to eat another
746 	 * comparison in this performance critical code.
747 	 */
748 	packet->rcd->dd->rhf_rcv_function_map[packet->etype](packet);
749 	packet->numpkt++;
750 
751 	/* Set up for the next packet */
752 	packet->rhqoff += packet->rsize;
753 	if (packet->rhqoff >= packet->maxcnt)
754 		packet->rhqoff = 0;
755 
756 	ret = check_max_packet(packet, thread);
757 
758 	packet->rhf_addr = (__le32 *)packet->rcd->rcvhdrq + packet->rhqoff +
759 				      packet->rcd->dd->rhf_offset;
760 	packet->rhf = rhf_to_cpu(packet->rhf_addr);
761 
762 	return ret;
763 }
764 
765 static inline void process_rcv_update(int last, struct hfi1_packet *packet)
766 {
767 	/*
768 	 * Update head regs etc., every 16 packets, if not last pkt,
769 	 * to help prevent rcvhdrq overflows, when many packets
770 	 * are processed and queue is nearly full.
771 	 * Don't request an interrupt for intermediate updates.
772 	 */
773 	if (!last && !(packet->numpkt & 0xf)) {
774 		update_usrhead(packet->rcd, packet->rhqoff, packet->updegr,
775 			       packet->etail, 0, 0);
776 		packet->updegr = 0;
777 	}
778 	packet->grh = NULL;
779 }
780 
781 static inline void finish_packet(struct hfi1_packet *packet)
782 {
783 	/*
784 	 * Nothing we need to free for the packet.
785 	 *
786 	 * The only thing we need to do is a final update and call for an
787 	 * interrupt
788 	 */
789 	update_usrhead(packet->rcd, packet->rcd->head, packet->updegr,
790 		       packet->etail, rcv_intr_dynamic, packet->numpkt);
791 }
792 
793 /*
794  * Handle receive interrupts when using the no dma rtail option.
795  */
796 int handle_receive_interrupt_nodma_rtail(struct hfi1_ctxtdata *rcd, int thread)
797 {
798 	u32 seq;
799 	int last = RCV_PKT_OK;
800 	struct hfi1_packet packet;
801 
802 	init_packet(rcd, &packet);
803 	seq = rhf_rcv_seq(packet.rhf);
804 	if (seq != rcd->seq_cnt) {
805 		last = RCV_PKT_DONE;
806 		goto bail;
807 	}
808 
809 	prescan_rxq(rcd, &packet);
810 
811 	while (last == RCV_PKT_OK) {
812 		last = process_rcv_packet(&packet, thread);
813 		seq = rhf_rcv_seq(packet.rhf);
814 		if (++rcd->seq_cnt > 13)
815 			rcd->seq_cnt = 1;
816 		if (seq != rcd->seq_cnt)
817 			last = RCV_PKT_DONE;
818 		process_rcv_update(last, &packet);
819 	}
820 	process_rcv_qp_work(&packet);
821 	rcd->head = packet.rhqoff;
822 bail:
823 	finish_packet(&packet);
824 	return last;
825 }
826 
827 int handle_receive_interrupt_dma_rtail(struct hfi1_ctxtdata *rcd, int thread)
828 {
829 	u32 hdrqtail;
830 	int last = RCV_PKT_OK;
831 	struct hfi1_packet packet;
832 
833 	init_packet(rcd, &packet);
834 	hdrqtail = get_rcvhdrtail(rcd);
835 	if (packet.rhqoff == hdrqtail) {
836 		last = RCV_PKT_DONE;
837 		goto bail;
838 	}
839 	smp_rmb();  /* prevent speculative reads of dma'ed hdrq */
840 
841 	prescan_rxq(rcd, &packet);
842 
843 	while (last == RCV_PKT_OK) {
844 		last = process_rcv_packet(&packet, thread);
845 		if (packet.rhqoff == hdrqtail)
846 			last = RCV_PKT_DONE;
847 		process_rcv_update(last, &packet);
848 	}
849 	process_rcv_qp_work(&packet);
850 	rcd->head = packet.rhqoff;
851 bail:
852 	finish_packet(&packet);
853 	return last;
854 }
855 
856 static inline void set_nodma_rtail(struct hfi1_devdata *dd, u16 ctxt)
857 {
858 	struct hfi1_ctxtdata *rcd;
859 	u16 i;
860 
861 	/*
862 	 * For dynamically allocated kernel contexts (like vnic) switch
863 	 * interrupt handler only for that context. Otherwise, switch
864 	 * interrupt handler for all statically allocated kernel contexts.
865 	 */
866 	if (ctxt >= dd->first_dyn_alloc_ctxt) {
867 		rcd = hfi1_rcd_get_by_index_safe(dd, ctxt);
868 		if (rcd) {
869 			rcd->do_interrupt =
870 				&handle_receive_interrupt_nodma_rtail;
871 			hfi1_rcd_put(rcd);
872 		}
873 		return;
874 	}
875 
876 	for (i = HFI1_CTRL_CTXT + 1; i < dd->first_dyn_alloc_ctxt; i++) {
877 		rcd = hfi1_rcd_get_by_index(dd, i);
878 		if (rcd)
879 			rcd->do_interrupt =
880 				&handle_receive_interrupt_nodma_rtail;
881 		hfi1_rcd_put(rcd);
882 	}
883 }
884 
885 static inline void set_dma_rtail(struct hfi1_devdata *dd, u16 ctxt)
886 {
887 	struct hfi1_ctxtdata *rcd;
888 	u16 i;
889 
890 	/*
891 	 * For dynamically allocated kernel contexts (like vnic) switch
892 	 * interrupt handler only for that context. Otherwise, switch
893 	 * interrupt handler for all statically allocated kernel contexts.
894 	 */
895 	if (ctxt >= dd->first_dyn_alloc_ctxt) {
896 		rcd = hfi1_rcd_get_by_index_safe(dd, ctxt);
897 		if (rcd) {
898 			rcd->do_interrupt =
899 				&handle_receive_interrupt_dma_rtail;
900 			hfi1_rcd_put(rcd);
901 		}
902 		return;
903 	}
904 
905 	for (i = HFI1_CTRL_CTXT + 1; i < dd->first_dyn_alloc_ctxt; i++) {
906 		rcd = hfi1_rcd_get_by_index(dd, i);
907 		if (rcd)
908 			rcd->do_interrupt =
909 				&handle_receive_interrupt_dma_rtail;
910 		hfi1_rcd_put(rcd);
911 	}
912 }
913 
914 void set_all_slowpath(struct hfi1_devdata *dd)
915 {
916 	struct hfi1_ctxtdata *rcd;
917 	u16 i;
918 
919 	/* HFI1_CTRL_CTXT must always use the slow path interrupt handler */
920 	for (i = HFI1_CTRL_CTXT + 1; i < dd->num_rcv_contexts; i++) {
921 		rcd = hfi1_rcd_get_by_index(dd, i);
922 		if (!rcd)
923 			continue;
924 		if (i < dd->first_dyn_alloc_ctxt || rcd->is_vnic)
925 			rcd->do_interrupt = &handle_receive_interrupt;
926 
927 		hfi1_rcd_put(rcd);
928 	}
929 }
930 
931 static inline int set_armed_to_active(struct hfi1_ctxtdata *rcd,
932 				      struct hfi1_packet *packet,
933 				      struct hfi1_devdata *dd)
934 {
935 	struct work_struct *lsaw = &rcd->ppd->linkstate_active_work;
936 	u8 etype = rhf_rcv_type(packet->rhf);
937 	u8 sc = SC15_PACKET;
938 
939 	if (etype == RHF_RCV_TYPE_IB) {
940 		struct ib_header *hdr = hfi1_get_msgheader(packet->rcd->dd,
941 							   packet->rhf_addr);
942 		sc = hfi1_9B_get_sc5(hdr, packet->rhf);
943 	} else if (etype == RHF_RCV_TYPE_BYPASS) {
944 		struct hfi1_16b_header *hdr = hfi1_get_16B_header(
945 						packet->rcd->dd,
946 						packet->rhf_addr);
947 		sc = hfi1_16B_get_sc(hdr);
948 	}
949 	if (sc != SC15_PACKET) {
950 		int hwstate = driver_lstate(rcd->ppd);
951 
952 		if (hwstate != IB_PORT_ACTIVE) {
953 			dd_dev_info(dd,
954 				    "Unexpected link state %s\n",
955 				    opa_lstate_name(hwstate));
956 			return 0;
957 		}
958 
959 		queue_work(rcd->ppd->link_wq, lsaw);
960 		return 1;
961 	}
962 	return 0;
963 }
964 
965 /*
966  * handle_receive_interrupt - receive a packet
967  * @rcd: the context
968  *
969  * Called from interrupt handler for errors or receive interrupt.
970  * This is the slow path interrupt handler.
971  */
972 int handle_receive_interrupt(struct hfi1_ctxtdata *rcd, int thread)
973 {
974 	struct hfi1_devdata *dd = rcd->dd;
975 	u32 hdrqtail;
976 	int needset, last = RCV_PKT_OK;
977 	struct hfi1_packet packet;
978 	int skip_pkt = 0;
979 
980 	/* Control context will always use the slow path interrupt handler */
981 	needset = (rcd->ctxt == HFI1_CTRL_CTXT) ? 0 : 1;
982 
983 	init_packet(rcd, &packet);
984 
985 	if (!HFI1_CAP_KGET_MASK(rcd->flags, DMA_RTAIL)) {
986 		u32 seq = rhf_rcv_seq(packet.rhf);
987 
988 		if (seq != rcd->seq_cnt) {
989 			last = RCV_PKT_DONE;
990 			goto bail;
991 		}
992 		hdrqtail = 0;
993 	} else {
994 		hdrqtail = get_rcvhdrtail(rcd);
995 		if (packet.rhqoff == hdrqtail) {
996 			last = RCV_PKT_DONE;
997 			goto bail;
998 		}
999 		smp_rmb();  /* prevent speculative reads of dma'ed hdrq */
1000 
1001 		/*
1002 		 * Control context can potentially receive an invalid
1003 		 * rhf. Drop such packets.
1004 		 */
1005 		if (rcd->ctxt == HFI1_CTRL_CTXT) {
1006 			u32 seq = rhf_rcv_seq(packet.rhf);
1007 
1008 			if (seq != rcd->seq_cnt)
1009 				skip_pkt = 1;
1010 		}
1011 	}
1012 
1013 	prescan_rxq(rcd, &packet);
1014 
1015 	while (last == RCV_PKT_OK) {
1016 		if (unlikely(dd->do_drop &&
1017 			     atomic_xchg(&dd->drop_packet, DROP_PACKET_OFF) ==
1018 			     DROP_PACKET_ON)) {
1019 			dd->do_drop = 0;
1020 
1021 			/* On to the next packet */
1022 			packet.rhqoff += packet.rsize;
1023 			packet.rhf_addr = (__le32 *)rcd->rcvhdrq +
1024 					  packet.rhqoff +
1025 					  dd->rhf_offset;
1026 			packet.rhf = rhf_to_cpu(packet.rhf_addr);
1027 
1028 		} else if (skip_pkt) {
1029 			last = skip_rcv_packet(&packet, thread);
1030 			skip_pkt = 0;
1031 		} else {
1032 			/* Auto activate link on non-SC15 packet receive */
1033 			if (unlikely(rcd->ppd->host_link_state ==
1034 				     HLS_UP_ARMED) &&
1035 			    set_armed_to_active(rcd, &packet, dd))
1036 				goto bail;
1037 			last = process_rcv_packet(&packet, thread);
1038 		}
1039 
1040 		if (!HFI1_CAP_KGET_MASK(rcd->flags, DMA_RTAIL)) {
1041 			u32 seq = rhf_rcv_seq(packet.rhf);
1042 
1043 			if (++rcd->seq_cnt > 13)
1044 				rcd->seq_cnt = 1;
1045 			if (seq != rcd->seq_cnt)
1046 				last = RCV_PKT_DONE;
1047 			if (needset) {
1048 				dd_dev_info(dd, "Switching to NO_DMA_RTAIL\n");
1049 				set_nodma_rtail(dd, rcd->ctxt);
1050 				needset = 0;
1051 			}
1052 		} else {
1053 			if (packet.rhqoff == hdrqtail)
1054 				last = RCV_PKT_DONE;
1055 			/*
1056 			 * Control context can potentially receive an invalid
1057 			 * rhf. Drop such packets.
1058 			 */
1059 			if (rcd->ctxt == HFI1_CTRL_CTXT) {
1060 				u32 seq = rhf_rcv_seq(packet.rhf);
1061 
1062 				if (++rcd->seq_cnt > 13)
1063 					rcd->seq_cnt = 1;
1064 				if (!last && (seq != rcd->seq_cnt))
1065 					skip_pkt = 1;
1066 			}
1067 
1068 			if (needset) {
1069 				dd_dev_info(dd,
1070 					    "Switching to DMA_RTAIL\n");
1071 				set_dma_rtail(dd, rcd->ctxt);
1072 				needset = 0;
1073 			}
1074 		}
1075 
1076 		process_rcv_update(last, &packet);
1077 	}
1078 
1079 	process_rcv_qp_work(&packet);
1080 	rcd->head = packet.rhqoff;
1081 
1082 bail:
1083 	/*
1084 	 * Always write head at end, and setup rcv interrupt, even
1085 	 * if no packets were processed.
1086 	 */
1087 	finish_packet(&packet);
1088 	return last;
1089 }
1090 
1091 /*
1092  * We may discover in the interrupt that the hardware link state has
1093  * changed from ARMED to ACTIVE (due to the arrival of a non-SC15 packet),
1094  * and we need to update the driver's notion of the link state.  We cannot
1095  * run set_link_state from interrupt context, so we queue this function on
1096  * a workqueue.
1097  *
1098  * We delay the regular interrupt processing until after the state changes
1099  * so that the link will be in the correct state by the time any application
1100  * we wake up attempts to send a reply to any message it received.
1101  * (Subsequent receive interrupts may possibly force the wakeup before we
1102  * update the link state.)
1103  *
1104  * The rcd is freed in hfi1_free_ctxtdata after hfi1_postinit_cleanup invokes
1105  * dd->f_cleanup(dd) to disable the interrupt handler and flush workqueues,
1106  * so we're safe from use-after-free of the rcd.
1107  */
1108 void receive_interrupt_work(struct work_struct *work)
1109 {
1110 	struct hfi1_pportdata *ppd = container_of(work, struct hfi1_pportdata,
1111 						  linkstate_active_work);
1112 	struct hfi1_devdata *dd = ppd->dd;
1113 	struct hfi1_ctxtdata *rcd;
1114 	u16 i;
1115 
1116 	/* Received non-SC15 packet implies neighbor_normal */
1117 	ppd->neighbor_normal = 1;
1118 	set_link_state(ppd, HLS_UP_ACTIVE);
1119 
1120 	/*
1121 	 * Interrupt all statically allocated kernel contexts that could
1122 	 * have had an interrupt during auto activation.
1123 	 */
1124 	for (i = HFI1_CTRL_CTXT; i < dd->first_dyn_alloc_ctxt; i++) {
1125 		rcd = hfi1_rcd_get_by_index(dd, i);
1126 		if (rcd)
1127 			force_recv_intr(rcd);
1128 		hfi1_rcd_put(rcd);
1129 	}
1130 }
1131 
1132 /*
1133  * Convert a given MTU size to the on-wire MAD packet enumeration.
1134  * Return -1 if the size is invalid.
1135  */
1136 int mtu_to_enum(u32 mtu, int default_if_bad)
1137 {
1138 	switch (mtu) {
1139 	case     0: return OPA_MTU_0;
1140 	case   256: return OPA_MTU_256;
1141 	case   512: return OPA_MTU_512;
1142 	case  1024: return OPA_MTU_1024;
1143 	case  2048: return OPA_MTU_2048;
1144 	case  4096: return OPA_MTU_4096;
1145 	case  8192: return OPA_MTU_8192;
1146 	case 10240: return OPA_MTU_10240;
1147 	}
1148 	return default_if_bad;
1149 }
1150 
1151 u16 enum_to_mtu(int mtu)
1152 {
1153 	switch (mtu) {
1154 	case OPA_MTU_0:     return 0;
1155 	case OPA_MTU_256:   return 256;
1156 	case OPA_MTU_512:   return 512;
1157 	case OPA_MTU_1024:  return 1024;
1158 	case OPA_MTU_2048:  return 2048;
1159 	case OPA_MTU_4096:  return 4096;
1160 	case OPA_MTU_8192:  return 8192;
1161 	case OPA_MTU_10240: return 10240;
1162 	default: return 0xffff;
1163 	}
1164 }
1165 
1166 /*
1167  * set_mtu - set the MTU
1168  * @ppd: the per port data
1169  *
1170  * We can handle "any" incoming size, the issue here is whether we
1171  * need to restrict our outgoing size.  We do not deal with what happens
1172  * to programs that are already running when the size changes.
1173  */
1174 int set_mtu(struct hfi1_pportdata *ppd)
1175 {
1176 	struct hfi1_devdata *dd = ppd->dd;
1177 	int i, drain, ret = 0, is_up = 0;
1178 
1179 	ppd->ibmtu = 0;
1180 	for (i = 0; i < ppd->vls_supported; i++)
1181 		if (ppd->ibmtu < dd->vld[i].mtu)
1182 			ppd->ibmtu = dd->vld[i].mtu;
1183 	ppd->ibmaxlen = ppd->ibmtu + lrh_max_header_bytes(ppd->dd);
1184 
1185 	mutex_lock(&ppd->hls_lock);
1186 	if (ppd->host_link_state == HLS_UP_INIT ||
1187 	    ppd->host_link_state == HLS_UP_ARMED ||
1188 	    ppd->host_link_state == HLS_UP_ACTIVE)
1189 		is_up = 1;
1190 
1191 	drain = !is_ax(dd) && is_up;
1192 
1193 	if (drain)
1194 		/*
1195 		 * MTU is specified per-VL. To ensure that no packet gets
1196 		 * stuck (due, e.g., to the MTU for the packet's VL being
1197 		 * reduced), empty the per-VL FIFOs before adjusting MTU.
1198 		 */
1199 		ret = stop_drain_data_vls(dd);
1200 
1201 	if (ret) {
1202 		dd_dev_err(dd, "%s: cannot stop/drain VLs - refusing to change per-VL MTUs\n",
1203 			   __func__);
1204 		goto err;
1205 	}
1206 
1207 	hfi1_set_ib_cfg(ppd, HFI1_IB_CFG_MTU, 0);
1208 
1209 	if (drain)
1210 		open_fill_data_vls(dd); /* reopen all VLs */
1211 
1212 err:
1213 	mutex_unlock(&ppd->hls_lock);
1214 
1215 	return ret;
1216 }
1217 
1218 int hfi1_set_lid(struct hfi1_pportdata *ppd, u32 lid, u8 lmc)
1219 {
1220 	struct hfi1_devdata *dd = ppd->dd;
1221 
1222 	ppd->lid = lid;
1223 	ppd->lmc = lmc;
1224 	hfi1_set_ib_cfg(ppd, HFI1_IB_CFG_LIDLMC, 0);
1225 
1226 	dd_dev_info(dd, "port %u: got a lid: 0x%x\n", ppd->port, lid);
1227 
1228 	return 0;
1229 }
1230 
1231 void shutdown_led_override(struct hfi1_pportdata *ppd)
1232 {
1233 	struct hfi1_devdata *dd = ppd->dd;
1234 
1235 	/*
1236 	 * This pairs with the memory barrier in hfi1_start_led_override to
1237 	 * ensure that we read the correct state of LED beaconing represented
1238 	 * by led_override_timer_active
1239 	 */
1240 	smp_rmb();
1241 	if (atomic_read(&ppd->led_override_timer_active)) {
1242 		del_timer_sync(&ppd->led_override_timer);
1243 		atomic_set(&ppd->led_override_timer_active, 0);
1244 		/* Ensure the atomic_set is visible to all CPUs */
1245 		smp_wmb();
1246 	}
1247 
1248 	/* Hand control of the LED to the DC for normal operation */
1249 	write_csr(dd, DCC_CFG_LED_CNTRL, 0);
1250 }
1251 
1252 static void run_led_override(struct timer_list *t)
1253 {
1254 	struct hfi1_pportdata *ppd = from_timer(ppd, t, led_override_timer);
1255 	struct hfi1_devdata *dd = ppd->dd;
1256 	unsigned long timeout;
1257 	int phase_idx;
1258 
1259 	if (!(dd->flags & HFI1_INITTED))
1260 		return;
1261 
1262 	phase_idx = ppd->led_override_phase & 1;
1263 
1264 	setextled(dd, phase_idx);
1265 
1266 	timeout = ppd->led_override_vals[phase_idx];
1267 
1268 	/* Set up for next phase */
1269 	ppd->led_override_phase = !ppd->led_override_phase;
1270 
1271 	mod_timer(&ppd->led_override_timer, jiffies + timeout);
1272 }
1273 
1274 /*
1275  * To have the LED blink in a particular pattern, provide timeon and timeoff
1276  * in milliseconds.
1277  * To turn off custom blinking and return to normal operation, use
1278  * shutdown_led_override()
1279  */
1280 void hfi1_start_led_override(struct hfi1_pportdata *ppd, unsigned int timeon,
1281 			     unsigned int timeoff)
1282 {
1283 	if (!(ppd->dd->flags & HFI1_INITTED))
1284 		return;
1285 
1286 	/* Convert to jiffies for direct use in timer */
1287 	ppd->led_override_vals[0] = msecs_to_jiffies(timeoff);
1288 	ppd->led_override_vals[1] = msecs_to_jiffies(timeon);
1289 
1290 	/* Arbitrarily start from LED on phase */
1291 	ppd->led_override_phase = 1;
1292 
1293 	/*
1294 	 * If the timer has not already been started, do so. Use a "quick"
1295 	 * timeout so the handler will be called soon to look at our request.
1296 	 */
1297 	if (!timer_pending(&ppd->led_override_timer)) {
1298 		timer_setup(&ppd->led_override_timer, run_led_override, 0);
1299 		ppd->led_override_timer.expires = jiffies + 1;
1300 		add_timer(&ppd->led_override_timer);
1301 		atomic_set(&ppd->led_override_timer_active, 1);
1302 		/* Ensure the atomic_set is visible to all CPUs */
1303 		smp_wmb();
1304 	}
1305 }
1306 
1307 /**
1308  * hfi1_reset_device - reset the chip if possible
1309  * @unit: the device to reset
1310  *
1311  * Whether or not reset is successful, we attempt to re-initialize the chip
1312  * (that is, much like a driver unload/reload).  We clear the INITTED flag
1313  * so that the various entry points will fail until we reinitialize.  For
1314  * now, we only allow this if no user contexts are open that use chip resources
1315  */
1316 int hfi1_reset_device(int unit)
1317 {
1318 	int ret;
1319 	struct hfi1_devdata *dd = hfi1_lookup(unit);
1320 	struct hfi1_pportdata *ppd;
1321 	int pidx;
1322 
1323 	if (!dd) {
1324 		ret = -ENODEV;
1325 		goto bail;
1326 	}
1327 
1328 	dd_dev_info(dd, "Reset on unit %u requested\n", unit);
1329 
1330 	if (!dd->kregbase1 || !(dd->flags & HFI1_PRESENT)) {
1331 		dd_dev_info(dd,
1332 			    "Invalid unit number %u or not initialized or not present\n",
1333 			    unit);
1334 		ret = -ENXIO;
1335 		goto bail;
1336 	}
1337 
1338 	/* If there are any user/vnic contexts, we cannot reset */
1339 	mutex_lock(&hfi1_mutex);
1340 	if (dd->rcd)
1341 		if (hfi1_stats.sps_ctxts) {
1342 			mutex_unlock(&hfi1_mutex);
1343 			ret = -EBUSY;
1344 			goto bail;
1345 		}
1346 	mutex_unlock(&hfi1_mutex);
1347 
1348 	for (pidx = 0; pidx < dd->num_pports; ++pidx) {
1349 		ppd = dd->pport + pidx;
1350 
1351 		shutdown_led_override(ppd);
1352 	}
1353 	if (dd->flags & HFI1_HAS_SEND_DMA)
1354 		sdma_exit(dd);
1355 
1356 	hfi1_reset_cpu_counters(dd);
1357 
1358 	ret = hfi1_init(dd, 1);
1359 
1360 	if (ret)
1361 		dd_dev_err(dd,
1362 			   "Reinitialize unit %u after reset failed with %d\n",
1363 			   unit, ret);
1364 	else
1365 		dd_dev_info(dd, "Reinitialized unit %u after resetting\n",
1366 			    unit);
1367 
1368 bail:
1369 	return ret;
1370 }
1371 
1372 static inline void hfi1_setup_ib_header(struct hfi1_packet *packet)
1373 {
1374 	packet->hdr = (struct hfi1_ib_message_header *)
1375 			hfi1_get_msgheader(packet->rcd->dd,
1376 					   packet->rhf_addr);
1377 	packet->hlen = (u8 *)packet->rhf_addr - (u8 *)packet->hdr;
1378 }
1379 
1380 static int hfi1_bypass_ingress_pkt_check(struct hfi1_packet *packet)
1381 {
1382 	struct hfi1_pportdata *ppd = packet->rcd->ppd;
1383 
1384 	/* slid and dlid cannot be 0 */
1385 	if ((!packet->slid) || (!packet->dlid))
1386 		return -EINVAL;
1387 
1388 	/* Compare port lid with incoming packet dlid */
1389 	if ((!(hfi1_is_16B_mcast(packet->dlid))) &&
1390 	    (packet->dlid !=
1391 		opa_get_lid(be32_to_cpu(OPA_LID_PERMISSIVE), 16B))) {
1392 		if (packet->dlid != ppd->lid)
1393 			return -EINVAL;
1394 	}
1395 
1396 	/* No multicast packets with SC15 */
1397 	if ((hfi1_is_16B_mcast(packet->dlid)) && (packet->sc == 0xF))
1398 		return -EINVAL;
1399 
1400 	/* Packets with permissive DLID always on SC15 */
1401 	if ((packet->dlid == opa_get_lid(be32_to_cpu(OPA_LID_PERMISSIVE),
1402 					 16B)) &&
1403 	    (packet->sc != 0xF))
1404 		return -EINVAL;
1405 
1406 	return 0;
1407 }
1408 
1409 static int hfi1_setup_9B_packet(struct hfi1_packet *packet)
1410 {
1411 	struct hfi1_ibport *ibp = rcd_to_iport(packet->rcd);
1412 	struct ib_header *hdr;
1413 	u8 lnh;
1414 
1415 	hfi1_setup_ib_header(packet);
1416 	hdr = packet->hdr;
1417 
1418 	lnh = ib_get_lnh(hdr);
1419 	if (lnh == HFI1_LRH_BTH) {
1420 		packet->ohdr = &hdr->u.oth;
1421 		packet->grh = NULL;
1422 	} else if (lnh == HFI1_LRH_GRH) {
1423 		u32 vtf;
1424 
1425 		packet->ohdr = &hdr->u.l.oth;
1426 		packet->grh = &hdr->u.l.grh;
1427 		if (packet->grh->next_hdr != IB_GRH_NEXT_HDR)
1428 			goto drop;
1429 		vtf = be32_to_cpu(packet->grh->version_tclass_flow);
1430 		if ((vtf >> IB_GRH_VERSION_SHIFT) != IB_GRH_VERSION)
1431 			goto drop;
1432 	} else {
1433 		goto drop;
1434 	}
1435 
1436 	/* Query commonly used fields from packet header */
1437 	packet->payload = packet->ebuf;
1438 	packet->opcode = ib_bth_get_opcode(packet->ohdr);
1439 	packet->slid = ib_get_slid(hdr);
1440 	packet->dlid = ib_get_dlid(hdr);
1441 	if (unlikely((packet->dlid >= be16_to_cpu(IB_MULTICAST_LID_BASE)) &&
1442 		     (packet->dlid != be16_to_cpu(IB_LID_PERMISSIVE))))
1443 		packet->dlid += opa_get_mcast_base(OPA_MCAST_NR) -
1444 				be16_to_cpu(IB_MULTICAST_LID_BASE);
1445 	packet->sl = ib_get_sl(hdr);
1446 	packet->sc = hfi1_9B_get_sc5(hdr, packet->rhf);
1447 	packet->pad = ib_bth_get_pad(packet->ohdr);
1448 	packet->extra_byte = 0;
1449 	packet->pkey = ib_bth_get_pkey(packet->ohdr);
1450 	packet->migrated = ib_bth_is_migration(packet->ohdr);
1451 
1452 	return 0;
1453 drop:
1454 	ibp->rvp.n_pkt_drops++;
1455 	return -EINVAL;
1456 }
1457 
1458 static int hfi1_setup_bypass_packet(struct hfi1_packet *packet)
1459 {
1460 	/*
1461 	 * Bypass packets have a different header/payload split
1462 	 * compared to an IB packet.
1463 	 * Current split is set such that 16 bytes of the actual
1464 	 * header is in the header buffer and the remining is in
1465 	 * the eager buffer. We chose 16 since hfi1 driver only
1466 	 * supports 16B bypass packets and we will be able to
1467 	 * receive the entire LRH with such a split.
1468 	 */
1469 
1470 	struct hfi1_ctxtdata *rcd = packet->rcd;
1471 	struct hfi1_pportdata *ppd = rcd->ppd;
1472 	struct hfi1_ibport *ibp = &ppd->ibport_data;
1473 	u8 l4;
1474 	u8 grh_len;
1475 
1476 	packet->hdr = (struct hfi1_16b_header *)
1477 			hfi1_get_16B_header(packet->rcd->dd,
1478 					    packet->rhf_addr);
1479 	packet->hlen = (u8 *)packet->rhf_addr - (u8 *)packet->hdr;
1480 
1481 	l4 = hfi1_16B_get_l4(packet->hdr);
1482 	if (l4 == OPA_16B_L4_IB_LOCAL) {
1483 		grh_len = 0;
1484 		packet->ohdr = packet->ebuf;
1485 		packet->grh = NULL;
1486 	} else if (l4 == OPA_16B_L4_IB_GLOBAL) {
1487 		u32 vtf;
1488 
1489 		grh_len = sizeof(struct ib_grh);
1490 		packet->ohdr = packet->ebuf + grh_len;
1491 		packet->grh = packet->ebuf;
1492 		if (packet->grh->next_hdr != IB_GRH_NEXT_HDR)
1493 			goto drop;
1494 		vtf = be32_to_cpu(packet->grh->version_tclass_flow);
1495 		if ((vtf >> IB_GRH_VERSION_SHIFT) != IB_GRH_VERSION)
1496 			goto drop;
1497 	} else {
1498 		goto drop;
1499 	}
1500 
1501 	/* Query commonly used fields from packet header */
1502 	packet->opcode = ib_bth_get_opcode(packet->ohdr);
1503 	/* hdr_len_by_opcode already has an IB LRH factored in */
1504 	packet->hlen = hdr_len_by_opcode[packet->opcode] +
1505 		(LRH_16B_BYTES - LRH_9B_BYTES) + grh_len;
1506 	packet->payload = packet->ebuf + packet->hlen - LRH_16B_BYTES;
1507 	packet->slid = hfi1_16B_get_slid(packet->hdr);
1508 	packet->dlid = hfi1_16B_get_dlid(packet->hdr);
1509 	if (unlikely(hfi1_is_16B_mcast(packet->dlid)))
1510 		packet->dlid += opa_get_mcast_base(OPA_MCAST_NR) -
1511 				opa_get_lid(opa_get_mcast_base(OPA_MCAST_NR),
1512 					    16B);
1513 	packet->sc = hfi1_16B_get_sc(packet->hdr);
1514 	packet->sl = ibp->sc_to_sl[packet->sc];
1515 	packet->pad = hfi1_16B_bth_get_pad(packet->ohdr);
1516 	packet->extra_byte = SIZE_OF_LT;
1517 	packet->pkey = hfi1_16B_get_pkey(packet->hdr);
1518 	packet->migrated = opa_bth_is_migration(packet->ohdr);
1519 
1520 	if (hfi1_bypass_ingress_pkt_check(packet))
1521 		goto drop;
1522 
1523 	return 0;
1524 drop:
1525 	hfi1_cdbg(PKT, "%s: packet dropped\n", __func__);
1526 	ibp->rvp.n_pkt_drops++;
1527 	return -EINVAL;
1528 }
1529 
1530 void handle_eflags(struct hfi1_packet *packet)
1531 {
1532 	struct hfi1_ctxtdata *rcd = packet->rcd;
1533 	u32 rte = rhf_rcv_type_err(packet->rhf);
1534 
1535 	rcv_hdrerr(rcd, rcd->ppd, packet);
1536 	if (rhf_err_flags(packet->rhf))
1537 		dd_dev_err(rcd->dd,
1538 			   "receive context %d: rhf 0x%016llx, errs [ %s%s%s%s%s%s%s%s] rte 0x%x\n",
1539 			   rcd->ctxt, packet->rhf,
1540 			   packet->rhf & RHF_K_HDR_LEN_ERR ? "k_hdr_len " : "",
1541 			   packet->rhf & RHF_DC_UNC_ERR ? "dc_unc " : "",
1542 			   packet->rhf & RHF_DC_ERR ? "dc " : "",
1543 			   packet->rhf & RHF_TID_ERR ? "tid " : "",
1544 			   packet->rhf & RHF_LEN_ERR ? "len " : "",
1545 			   packet->rhf & RHF_ECC_ERR ? "ecc " : "",
1546 			   packet->rhf & RHF_VCRC_ERR ? "vcrc " : "",
1547 			   packet->rhf & RHF_ICRC_ERR ? "icrc " : "",
1548 			   rte);
1549 }
1550 
1551 /*
1552  * The following functions are called by the interrupt handler. They are type
1553  * specific handlers for each packet type.
1554  */
1555 int process_receive_ib(struct hfi1_packet *packet)
1556 {
1557 	if (unlikely(hfi1_dbg_fault_packet(packet)))
1558 		return RHF_RCV_CONTINUE;
1559 
1560 	if (hfi1_setup_9B_packet(packet))
1561 		return RHF_RCV_CONTINUE;
1562 
1563 	trace_hfi1_rcvhdr(packet);
1564 
1565 	if (unlikely(rhf_err_flags(packet->rhf))) {
1566 		handle_eflags(packet);
1567 		return RHF_RCV_CONTINUE;
1568 	}
1569 
1570 	hfi1_ib_rcv(packet);
1571 	return RHF_RCV_CONTINUE;
1572 }
1573 
1574 static inline bool hfi1_is_vnic_packet(struct hfi1_packet *packet)
1575 {
1576 	/* Packet received in VNIC context via RSM */
1577 	if (packet->rcd->is_vnic)
1578 		return true;
1579 
1580 	if ((hfi1_16B_get_l2(packet->ebuf) == OPA_16B_L2_TYPE) &&
1581 	    (hfi1_16B_get_l4(packet->ebuf) == OPA_16B_L4_ETHR))
1582 		return true;
1583 
1584 	return false;
1585 }
1586 
1587 int process_receive_bypass(struct hfi1_packet *packet)
1588 {
1589 	struct hfi1_devdata *dd = packet->rcd->dd;
1590 
1591 	if (hfi1_is_vnic_packet(packet)) {
1592 		hfi1_vnic_bypass_rcv(packet);
1593 		return RHF_RCV_CONTINUE;
1594 	}
1595 
1596 	if (hfi1_setup_bypass_packet(packet))
1597 		return RHF_RCV_CONTINUE;
1598 
1599 	trace_hfi1_rcvhdr(packet);
1600 
1601 	if (unlikely(rhf_err_flags(packet->rhf))) {
1602 		handle_eflags(packet);
1603 		return RHF_RCV_CONTINUE;
1604 	}
1605 
1606 	if (hfi1_16B_get_l2(packet->hdr) == 0x2) {
1607 		hfi1_16B_rcv(packet);
1608 	} else {
1609 		dd_dev_err(dd,
1610 			   "Bypass packets other than 16B are not supported in normal operation. Dropping\n");
1611 		incr_cntr64(&dd->sw_rcv_bypass_packet_errors);
1612 		if (!(dd->err_info_rcvport.status_and_code &
1613 		      OPA_EI_STATUS_SMASK)) {
1614 			u64 *flits = packet->ebuf;
1615 
1616 			if (flits && !(packet->rhf & RHF_LEN_ERR)) {
1617 				dd->err_info_rcvport.packet_flit1 = flits[0];
1618 				dd->err_info_rcvport.packet_flit2 =
1619 					packet->tlen > sizeof(flits[0]) ?
1620 					flits[1] : 0;
1621 			}
1622 			dd->err_info_rcvport.status_and_code |=
1623 				(OPA_EI_STATUS_SMASK | BAD_L2_ERR);
1624 		}
1625 	}
1626 	return RHF_RCV_CONTINUE;
1627 }
1628 
1629 int process_receive_error(struct hfi1_packet *packet)
1630 {
1631 	/* KHdrHCRCErr -- KDETH packet with a bad HCRC */
1632 	if (unlikely(
1633 		 hfi1_dbg_fault_suppress_err(&packet->rcd->dd->verbs_dev) &&
1634 		 rhf_rcv_type_err(packet->rhf) == 3))
1635 		return RHF_RCV_CONTINUE;
1636 
1637 	hfi1_setup_ib_header(packet);
1638 	handle_eflags(packet);
1639 
1640 	if (unlikely(rhf_err_flags(packet->rhf)))
1641 		dd_dev_err(packet->rcd->dd,
1642 			   "Unhandled error packet received. Dropping.\n");
1643 
1644 	return RHF_RCV_CONTINUE;
1645 }
1646 
1647 int kdeth_process_expected(struct hfi1_packet *packet)
1648 {
1649 	if (unlikely(hfi1_dbg_fault_packet(packet)))
1650 		return RHF_RCV_CONTINUE;
1651 
1652 	hfi1_setup_ib_header(packet);
1653 	if (unlikely(rhf_err_flags(packet->rhf)))
1654 		handle_eflags(packet);
1655 
1656 	dd_dev_err(packet->rcd->dd,
1657 		   "Unhandled expected packet received. Dropping.\n");
1658 	return RHF_RCV_CONTINUE;
1659 }
1660 
1661 int kdeth_process_eager(struct hfi1_packet *packet)
1662 {
1663 	hfi1_setup_ib_header(packet);
1664 	if (unlikely(rhf_err_flags(packet->rhf)))
1665 		handle_eflags(packet);
1666 	if (unlikely(hfi1_dbg_fault_packet(packet)))
1667 		return RHF_RCV_CONTINUE;
1668 
1669 	dd_dev_err(packet->rcd->dd,
1670 		   "Unhandled eager packet received. Dropping.\n");
1671 	return RHF_RCV_CONTINUE;
1672 }
1673 
1674 int process_receive_invalid(struct hfi1_packet *packet)
1675 {
1676 	dd_dev_err(packet->rcd->dd, "Invalid packet type %d. Dropping\n",
1677 		   rhf_rcv_type(packet->rhf));
1678 	return RHF_RCV_CONTINUE;
1679 }
1680 
1681 void seqfile_dump_rcd(struct seq_file *s, struct hfi1_ctxtdata *rcd)
1682 {
1683 	struct hfi1_packet packet;
1684 	struct ps_mdata mdata;
1685 
1686 	seq_printf(s, "Rcd %u: RcvHdr cnt %u entsize %u %s head %llu tail %llu\n",
1687 		   rcd->ctxt, rcd->rcvhdrq_cnt, rcd->rcvhdrqentsize,
1688 		   HFI1_CAP_KGET_MASK(rcd->flags, DMA_RTAIL) ?
1689 		   "dma_rtail" : "nodma_rtail",
1690 		   read_uctxt_csr(rcd->dd, rcd->ctxt, RCV_HDR_HEAD) &
1691 		   RCV_HDR_HEAD_HEAD_MASK,
1692 		   read_uctxt_csr(rcd->dd, rcd->ctxt, RCV_HDR_TAIL));
1693 
1694 	init_packet(rcd, &packet);
1695 	init_ps_mdata(&mdata, &packet);
1696 
1697 	while (1) {
1698 		struct hfi1_devdata *dd = rcd->dd;
1699 		__le32 *rhf_addr = (__le32 *)rcd->rcvhdrq + mdata.ps_head +
1700 					 dd->rhf_offset;
1701 		struct ib_header *hdr;
1702 		u64 rhf = rhf_to_cpu(rhf_addr);
1703 		u32 etype = rhf_rcv_type(rhf), qpn;
1704 		u8 opcode;
1705 		u32 psn;
1706 		u8 lnh;
1707 
1708 		if (ps_done(&mdata, rhf, rcd))
1709 			break;
1710 
1711 		if (ps_skip(&mdata, rhf, rcd))
1712 			goto next;
1713 
1714 		if (etype > RHF_RCV_TYPE_IB)
1715 			goto next;
1716 
1717 		packet.hdr = hfi1_get_msgheader(dd, rhf_addr);
1718 		hdr = packet.hdr;
1719 
1720 		lnh = be16_to_cpu(hdr->lrh[0]) & 3;
1721 
1722 		if (lnh == HFI1_LRH_BTH)
1723 			packet.ohdr = &hdr->u.oth;
1724 		else if (lnh == HFI1_LRH_GRH)
1725 			packet.ohdr = &hdr->u.l.oth;
1726 		else
1727 			goto next; /* just in case */
1728 
1729 		opcode = (be32_to_cpu(packet.ohdr->bth[0]) >> 24);
1730 		qpn = be32_to_cpu(packet.ohdr->bth[1]) & RVT_QPN_MASK;
1731 		psn = mask_psn(be32_to_cpu(packet.ohdr->bth[2]));
1732 
1733 		seq_printf(s, "\tEnt %u: opcode 0x%x, qpn 0x%x, psn 0x%x\n",
1734 			   mdata.ps_head, opcode, qpn, psn);
1735 next:
1736 		update_ps_mdata(&mdata, rcd);
1737 	}
1738 }
1739