1 /*
2  * Copyright (c) 2021 Cornelis Networks. All rights reserved.
3  * Copyright (c) 2013 Intel Corporation. All rights reserved.
4  * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
5  * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
6  *
7  * This software is available to you under a choice of one of two
8  * licenses.  You may choose to be licensed under the terms of the GNU
9  * General Public License (GPL) Version 2, available from the file
10  * COPYING in the main directory of this source tree, or the
11  * OpenIB.org BSD license below:
12  *
13  *     Redistribution and use in source and binary forms, with or
14  *     without modification, are permitted provided that the following
15  *     conditions are met:
16  *
17  *      - Redistributions of source code must retain the above
18  *        copyright notice, this list of conditions and the following
19  *        disclaimer.
20  *
21  *      - Redistributions in binary form must reproduce the above
22  *        copyright notice, this list of conditions and the following
23  *        disclaimer in the documentation and/or other materials
24  *        provided with the distribution.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33  * SOFTWARE.
34  */
35 
36 #include <linux/spinlock.h>
37 #include <linux/pci.h>
38 #include <linux/io.h>
39 #include <linux/delay.h>
40 #include <linux/netdevice.h>
41 #include <linux/vmalloc.h>
42 #include <linux/module.h>
43 #include <linux/prefetch.h>
44 
45 #include "qib.h"
46 
47 /*
48  * The size has to be longer than this string, so we can append
49  * board/chip information to it in the init code.
50  */
51 const char ib_qib_version[] = QIB_DRIVER_VERSION "\n";
52 
53 DEFINE_MUTEX(qib_mutex);	/* general driver use */
54 
55 unsigned qib_ibmtu;
56 module_param_named(ibmtu, qib_ibmtu, uint, S_IRUGO);
57 MODULE_PARM_DESC(ibmtu, "Set max IB MTU (0=2KB, 1=256, 2=512, ... 5=4096");
58 
59 unsigned qib_compat_ddr_negotiate = 1;
60 module_param_named(compat_ddr_negotiate, qib_compat_ddr_negotiate, uint,
61 		   S_IWUSR | S_IRUGO);
62 MODULE_PARM_DESC(compat_ddr_negotiate,
63 		 "Attempt pre-IBTA 1.2 DDR speed negotiation");
64 
65 MODULE_LICENSE("Dual BSD/GPL");
66 MODULE_AUTHOR("Cornelis <support@cornelisnetworks.com>");
67 MODULE_DESCRIPTION("Cornelis IB driver");
68 
69 /*
70  * QIB_PIO_MAXIBHDR is the max IB header size allowed for in our
71  * PIO send buffers.  This is well beyond anything currently
72  * defined in the InfiniBand spec.
73  */
74 #define QIB_PIO_MAXIBHDR 128
75 
76 /*
77  * QIB_MAX_PKT_RCV is the max # if packets processed per receive interrupt.
78  */
79 #define QIB_MAX_PKT_RECV 64
80 
81 struct qlogic_ib_stats qib_stats;
82 
83 struct pci_dev *qib_get_pci_dev(struct rvt_dev_info *rdi)
84 {
85 	struct qib_ibdev *ibdev = container_of(rdi, struct qib_ibdev, rdi);
86 	struct qib_devdata *dd = container_of(ibdev,
87 					      struct qib_devdata, verbs_dev);
88 	return dd->pcidev;
89 }
90 
91 /*
92  * Return count of units with at least one port ACTIVE.
93  */
94 int qib_count_active_units(void)
95 {
96 	struct qib_devdata *dd;
97 	struct qib_pportdata *ppd;
98 	unsigned long index, flags;
99 	int pidx, nunits_active = 0;
100 
101 	xa_lock_irqsave(&qib_dev_table, flags);
102 	xa_for_each(&qib_dev_table, index, dd) {
103 		if (!(dd->flags & QIB_PRESENT) || !dd->kregbase)
104 			continue;
105 		for (pidx = 0; pidx < dd->num_pports; ++pidx) {
106 			ppd = dd->pport + pidx;
107 			if (ppd->lid && (ppd->lflags & (QIBL_LINKINIT |
108 					 QIBL_LINKARMED | QIBL_LINKACTIVE))) {
109 				nunits_active++;
110 				break;
111 			}
112 		}
113 	}
114 	xa_unlock_irqrestore(&qib_dev_table, flags);
115 	return nunits_active;
116 }
117 
118 /*
119  * Return count of all units, optionally return in arguments
120  * the number of usable (present) units, and the number of
121  * ports that are up.
122  */
123 int qib_count_units(int *npresentp, int *nupp)
124 {
125 	int nunits = 0, npresent = 0, nup = 0;
126 	struct qib_devdata *dd;
127 	unsigned long index, flags;
128 	int pidx;
129 	struct qib_pportdata *ppd;
130 
131 	xa_lock_irqsave(&qib_dev_table, flags);
132 	xa_for_each(&qib_dev_table, index, dd) {
133 		nunits++;
134 		if ((dd->flags & QIB_PRESENT) && dd->kregbase)
135 			npresent++;
136 		for (pidx = 0; pidx < dd->num_pports; ++pidx) {
137 			ppd = dd->pport + pidx;
138 			if (ppd->lid && (ppd->lflags & (QIBL_LINKINIT |
139 					 QIBL_LINKARMED | QIBL_LINKACTIVE)))
140 				nup++;
141 		}
142 	}
143 	xa_unlock_irqrestore(&qib_dev_table, flags);
144 
145 	if (npresentp)
146 		*npresentp = npresent;
147 	if (nupp)
148 		*nupp = nup;
149 
150 	return nunits;
151 }
152 
153 /**
154  * qib_wait_linkstate - wait for an IB link state change to occur
155  * @ppd: the qlogic_ib device
156  * @state: the state to wait for
157  * @msecs: the number of milliseconds to wait
158  *
159  * wait up to msecs milliseconds for IB link state change to occur for
160  * now, take the easy polling route.  Currently used only by
161  * qib_set_linkstate.  Returns 0 if state reached, otherwise
162  * -ETIMEDOUT state can have multiple states set, for any of several
163  * transitions.
164  */
165 int qib_wait_linkstate(struct qib_pportdata *ppd, u32 state, int msecs)
166 {
167 	int ret;
168 	unsigned long flags;
169 
170 	spin_lock_irqsave(&ppd->lflags_lock, flags);
171 	if (ppd->state_wanted) {
172 		spin_unlock_irqrestore(&ppd->lflags_lock, flags);
173 		ret = -EBUSY;
174 		goto bail;
175 	}
176 	ppd->state_wanted = state;
177 	spin_unlock_irqrestore(&ppd->lflags_lock, flags);
178 	wait_event_interruptible_timeout(ppd->state_wait,
179 					 (ppd->lflags & state),
180 					 msecs_to_jiffies(msecs));
181 	spin_lock_irqsave(&ppd->lflags_lock, flags);
182 	ppd->state_wanted = 0;
183 	spin_unlock_irqrestore(&ppd->lflags_lock, flags);
184 
185 	if (!(ppd->lflags & state))
186 		ret = -ETIMEDOUT;
187 	else
188 		ret = 0;
189 bail:
190 	return ret;
191 }
192 
193 int qib_set_linkstate(struct qib_pportdata *ppd, u8 newstate)
194 {
195 	u32 lstate;
196 	int ret;
197 	struct qib_devdata *dd = ppd->dd;
198 	unsigned long flags;
199 
200 	switch (newstate) {
201 	case QIB_IB_LINKDOWN_ONLY:
202 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
203 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_NOP);
204 		/* don't wait */
205 		ret = 0;
206 		goto bail;
207 
208 	case QIB_IB_LINKDOWN:
209 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
210 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_POLL);
211 		/* don't wait */
212 		ret = 0;
213 		goto bail;
214 
215 	case QIB_IB_LINKDOWN_SLEEP:
216 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
217 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_SLEEP);
218 		/* don't wait */
219 		ret = 0;
220 		goto bail;
221 
222 	case QIB_IB_LINKDOWN_DISABLE:
223 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
224 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_DISABLE);
225 		/* don't wait */
226 		ret = 0;
227 		goto bail;
228 
229 	case QIB_IB_LINKARM:
230 		if (ppd->lflags & QIBL_LINKARMED) {
231 			ret = 0;
232 			goto bail;
233 		}
234 		if (!(ppd->lflags & (QIBL_LINKINIT | QIBL_LINKACTIVE))) {
235 			ret = -EINVAL;
236 			goto bail;
237 		}
238 		/*
239 		 * Since the port can be ACTIVE when we ask for ARMED,
240 		 * clear QIBL_LINKV so we can wait for a transition.
241 		 * If the link isn't ARMED, then something else happened
242 		 * and there is no point waiting for ARMED.
243 		 */
244 		spin_lock_irqsave(&ppd->lflags_lock, flags);
245 		ppd->lflags &= ~QIBL_LINKV;
246 		spin_unlock_irqrestore(&ppd->lflags_lock, flags);
247 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
248 				 IB_LINKCMD_ARMED | IB_LINKINITCMD_NOP);
249 		lstate = QIBL_LINKV;
250 		break;
251 
252 	case QIB_IB_LINKACTIVE:
253 		if (ppd->lflags & QIBL_LINKACTIVE) {
254 			ret = 0;
255 			goto bail;
256 		}
257 		if (!(ppd->lflags & QIBL_LINKARMED)) {
258 			ret = -EINVAL;
259 			goto bail;
260 		}
261 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
262 				 IB_LINKCMD_ACTIVE | IB_LINKINITCMD_NOP);
263 		lstate = QIBL_LINKACTIVE;
264 		break;
265 
266 	default:
267 		ret = -EINVAL;
268 		goto bail;
269 	}
270 	ret = qib_wait_linkstate(ppd, lstate, 10);
271 
272 bail:
273 	return ret;
274 }
275 
276 /*
277  * Get address of eager buffer from it's index (allocated in chunks, not
278  * contiguous).
279  */
280 static inline void *qib_get_egrbuf(const struct qib_ctxtdata *rcd, u32 etail)
281 {
282 	const u32 chunk = etail >> rcd->rcvegrbufs_perchunk_shift;
283 	const u32 idx =  etail & ((u32)rcd->rcvegrbufs_perchunk - 1);
284 
285 	return rcd->rcvegrbuf[chunk] + (idx << rcd->dd->rcvegrbufsize_shift);
286 }
287 
288 /*
289  * Returns 1 if error was a CRC, else 0.
290  * Needed for some chip's synthesized error counters.
291  */
292 static u32 qib_rcv_hdrerr(struct qib_ctxtdata *rcd, struct qib_pportdata *ppd,
293 			  u32 ctxt, u32 eflags, u32 l, u32 etail,
294 			  __le32 *rhf_addr, struct qib_message_header *rhdr)
295 {
296 	u32 ret = 0;
297 
298 	if (eflags & (QLOGIC_IB_RHF_H_ICRCERR | QLOGIC_IB_RHF_H_VCRCERR))
299 		ret = 1;
300 	else if (eflags == QLOGIC_IB_RHF_H_TIDERR) {
301 		/* For TIDERR and RC QPs premptively schedule a NAK */
302 		struct ib_header *hdr = (struct ib_header *)rhdr;
303 		struct ib_other_headers *ohdr = NULL;
304 		struct qib_ibport *ibp = &ppd->ibport_data;
305 		struct qib_devdata *dd = ppd->dd;
306 		struct rvt_dev_info *rdi = &dd->verbs_dev.rdi;
307 		struct rvt_qp *qp = NULL;
308 		u32 tlen = qib_hdrget_length_in_bytes(rhf_addr);
309 		u16 lid  = be16_to_cpu(hdr->lrh[1]);
310 		int lnh = be16_to_cpu(hdr->lrh[0]) & 3;
311 		u32 qp_num;
312 		u32 opcode;
313 		u32 psn;
314 		int diff;
315 
316 		/* Sanity check packet */
317 		if (tlen < 24)
318 			goto drop;
319 
320 		if (lid < be16_to_cpu(IB_MULTICAST_LID_BASE)) {
321 			lid &= ~((1 << ppd->lmc) - 1);
322 			if (unlikely(lid != ppd->lid))
323 				goto drop;
324 		}
325 
326 		/* Check for GRH */
327 		if (lnh == QIB_LRH_BTH)
328 			ohdr = &hdr->u.oth;
329 		else if (lnh == QIB_LRH_GRH) {
330 			u32 vtf;
331 
332 			ohdr = &hdr->u.l.oth;
333 			if (hdr->u.l.grh.next_hdr != IB_GRH_NEXT_HDR)
334 				goto drop;
335 			vtf = be32_to_cpu(hdr->u.l.grh.version_tclass_flow);
336 			if ((vtf >> IB_GRH_VERSION_SHIFT) != IB_GRH_VERSION)
337 				goto drop;
338 		} else
339 			goto drop;
340 
341 		/* Get opcode and PSN from packet */
342 		opcode = be32_to_cpu(ohdr->bth[0]);
343 		opcode >>= 24;
344 		psn = be32_to_cpu(ohdr->bth[2]);
345 
346 		/* Get the destination QP number. */
347 		qp_num = be32_to_cpu(ohdr->bth[1]) & RVT_QPN_MASK;
348 		if (qp_num != QIB_MULTICAST_QPN) {
349 			int ruc_res;
350 
351 			rcu_read_lock();
352 			qp = rvt_lookup_qpn(rdi, &ibp->rvp, qp_num);
353 			if (!qp) {
354 				rcu_read_unlock();
355 				goto drop;
356 			}
357 
358 			/*
359 			 * Handle only RC QPs - for other QP types drop error
360 			 * packet.
361 			 */
362 			spin_lock(&qp->r_lock);
363 
364 			/* Check for valid receive state. */
365 			if (!(ib_rvt_state_ops[qp->state] &
366 			      RVT_PROCESS_RECV_OK)) {
367 				ibp->rvp.n_pkt_drops++;
368 				goto unlock;
369 			}
370 
371 			switch (qp->ibqp.qp_type) {
372 			case IB_QPT_RC:
373 				ruc_res =
374 					qib_ruc_check_hdr(
375 						ibp, hdr,
376 						lnh == QIB_LRH_GRH,
377 						qp,
378 						be32_to_cpu(ohdr->bth[0]));
379 				if (ruc_res)
380 					goto unlock;
381 
382 				/* Only deal with RDMA Writes for now */
383 				if (opcode <
384 				    IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) {
385 					diff = qib_cmp24(psn, qp->r_psn);
386 					if (!qp->r_nak_state && diff >= 0) {
387 						ibp->rvp.n_rc_seqnak++;
388 						qp->r_nak_state =
389 							IB_NAK_PSN_ERROR;
390 						/* Use the expected PSN. */
391 						qp->r_ack_psn = qp->r_psn;
392 						/*
393 						 * Wait to send the sequence
394 						 * NAK until all packets
395 						 * in the receive queue have
396 						 * been processed.
397 						 * Otherwise, we end up
398 						 * propagating congestion.
399 						 */
400 						if (list_empty(&qp->rspwait)) {
401 							qp->r_flags |=
402 								RVT_R_RSP_NAK;
403 							rvt_get_qp(qp);
404 							list_add_tail(
405 							 &qp->rspwait,
406 							 &rcd->qp_wait_list);
407 						}
408 					} /* Out of sequence NAK */
409 				} /* QP Request NAKs */
410 				break;
411 			case IB_QPT_SMI:
412 			case IB_QPT_GSI:
413 			case IB_QPT_UD:
414 			case IB_QPT_UC:
415 			default:
416 				/* For now don't handle any other QP types */
417 				break;
418 			}
419 
420 unlock:
421 			spin_unlock(&qp->r_lock);
422 			rcu_read_unlock();
423 		} /* Unicast QP */
424 	} /* Valid packet with TIDErr */
425 
426 drop:
427 	return ret;
428 }
429 
430 /*
431  * qib_kreceive - receive a packet
432  * @rcd: the qlogic_ib context
433  * @llic: gets count of good packets needed to clear lli,
434  *          (used with chips that need need to track crcs for lli)
435  *
436  * called from interrupt handler for errors or receive interrupt
437  * Returns number of CRC error packets, needed by some chips for
438  * local link integrity tracking.   crcs are adjusted down by following
439  * good packets, if any, and count of good packets is also tracked.
440  */
441 u32 qib_kreceive(struct qib_ctxtdata *rcd, u32 *llic, u32 *npkts)
442 {
443 	struct qib_devdata *dd = rcd->dd;
444 	struct qib_pportdata *ppd = rcd->ppd;
445 	__le32 *rhf_addr;
446 	void *ebuf;
447 	const u32 rsize = dd->rcvhdrentsize;        /* words */
448 	const u32 maxcnt = dd->rcvhdrcnt * rsize;   /* words */
449 	u32 etail = -1, l, hdrqtail;
450 	struct qib_message_header *hdr;
451 	u32 eflags, etype, tlen, i = 0, updegr = 0, crcs = 0;
452 	int last;
453 	u64 lval;
454 	struct rvt_qp *qp, *nqp;
455 
456 	l = rcd->head;
457 	rhf_addr = (__le32 *) rcd->rcvhdrq + l + dd->rhf_offset;
458 	if (dd->flags & QIB_NODMA_RTAIL) {
459 		u32 seq = qib_hdrget_seq(rhf_addr);
460 
461 		if (seq != rcd->seq_cnt)
462 			goto bail;
463 		hdrqtail = 0;
464 	} else {
465 		hdrqtail = qib_get_rcvhdrtail(rcd);
466 		if (l == hdrqtail)
467 			goto bail;
468 		smp_rmb();  /* prevent speculative reads of dma'ed hdrq */
469 	}
470 
471 	for (last = 0, i = 1; !last; i += !last) {
472 		hdr = dd->f_get_msgheader(dd, rhf_addr);
473 		eflags = qib_hdrget_err_flags(rhf_addr);
474 		etype = qib_hdrget_rcv_type(rhf_addr);
475 		/* total length */
476 		tlen = qib_hdrget_length_in_bytes(rhf_addr);
477 		ebuf = NULL;
478 		if ((dd->flags & QIB_NODMA_RTAIL) ?
479 		    qib_hdrget_use_egr_buf(rhf_addr) :
480 		    (etype != RCVHQ_RCV_TYPE_EXPECTED)) {
481 			etail = qib_hdrget_index(rhf_addr);
482 			updegr = 1;
483 			if (tlen > sizeof(*hdr) ||
484 			    etype >= RCVHQ_RCV_TYPE_NON_KD) {
485 				ebuf = qib_get_egrbuf(rcd, etail);
486 				prefetch_range(ebuf, tlen - sizeof(*hdr));
487 			}
488 		}
489 		if (!eflags) {
490 			u16 lrh_len = be16_to_cpu(hdr->lrh[2]) << 2;
491 
492 			if (lrh_len != tlen) {
493 				qib_stats.sps_lenerrs++;
494 				goto move_along;
495 			}
496 		}
497 		if (etype == RCVHQ_RCV_TYPE_NON_KD && !eflags &&
498 		    ebuf == NULL &&
499 		    tlen > (dd->rcvhdrentsize - 2 + 1 -
500 				qib_hdrget_offset(rhf_addr)) << 2) {
501 			goto move_along;
502 		}
503 
504 		/*
505 		 * Both tiderr and qibhdrerr are set for all plain IB
506 		 * packets; only qibhdrerr should be set.
507 		 */
508 		if (unlikely(eflags))
509 			crcs += qib_rcv_hdrerr(rcd, ppd, rcd->ctxt, eflags, l,
510 					       etail, rhf_addr, hdr);
511 		else if (etype == RCVHQ_RCV_TYPE_NON_KD) {
512 			qib_ib_rcv(rcd, hdr, ebuf, tlen);
513 			if (crcs)
514 				crcs--;
515 			else if (llic && *llic)
516 				--*llic;
517 		}
518 move_along:
519 		l += rsize;
520 		if (l >= maxcnt)
521 			l = 0;
522 		if (i == QIB_MAX_PKT_RECV)
523 			last = 1;
524 
525 		rhf_addr = (__le32 *) rcd->rcvhdrq + l + dd->rhf_offset;
526 		if (dd->flags & QIB_NODMA_RTAIL) {
527 			u32 seq = qib_hdrget_seq(rhf_addr);
528 
529 			if (++rcd->seq_cnt > 13)
530 				rcd->seq_cnt = 1;
531 			if (seq != rcd->seq_cnt)
532 				last = 1;
533 		} else if (l == hdrqtail)
534 			last = 1;
535 		/*
536 		 * Update head regs etc., every 16 packets, if not last pkt,
537 		 * to help prevent rcvhdrq overflows, when many packets
538 		 * are processed and queue is nearly full.
539 		 * Don't request an interrupt for intermediate updates.
540 		 */
541 		lval = l;
542 		if (!last && !(i & 0xf)) {
543 			dd->f_update_usrhead(rcd, lval, updegr, etail, i);
544 			updegr = 0;
545 		}
546 	}
547 
548 	rcd->head = l;
549 
550 	/*
551 	 * Iterate over all QPs waiting to respond.
552 	 * The list won't change since the IRQ is only run on one CPU.
553 	 */
554 	list_for_each_entry_safe(qp, nqp, &rcd->qp_wait_list, rspwait) {
555 		list_del_init(&qp->rspwait);
556 		if (qp->r_flags & RVT_R_RSP_NAK) {
557 			qp->r_flags &= ~RVT_R_RSP_NAK;
558 			qib_send_rc_ack(qp);
559 		}
560 		if (qp->r_flags & RVT_R_RSP_SEND) {
561 			unsigned long flags;
562 
563 			qp->r_flags &= ~RVT_R_RSP_SEND;
564 			spin_lock_irqsave(&qp->s_lock, flags);
565 			if (ib_rvt_state_ops[qp->state] &
566 					RVT_PROCESS_OR_FLUSH_SEND)
567 				qib_schedule_send(qp);
568 			spin_unlock_irqrestore(&qp->s_lock, flags);
569 		}
570 		rvt_put_qp(qp);
571 	}
572 
573 bail:
574 	/* Report number of packets consumed */
575 	if (npkts)
576 		*npkts = i;
577 
578 	/*
579 	 * Always write head at end, and setup rcv interrupt, even
580 	 * if no packets were processed.
581 	 */
582 	lval = (u64)rcd->head | dd->rhdrhead_intr_off;
583 	dd->f_update_usrhead(rcd, lval, updegr, etail, i);
584 	return crcs;
585 }
586 
587 /**
588  * qib_set_mtu - set the MTU
589  * @ppd: the perport data
590  * @arg: the new MTU
591  *
592  * We can handle "any" incoming size, the issue here is whether we
593  * need to restrict our outgoing size.   For now, we don't do any
594  * sanity checking on this, and we don't deal with what happens to
595  * programs that are already running when the size changes.
596  * NOTE: changing the MTU will usually cause the IBC to go back to
597  * link INIT state...
598  */
599 int qib_set_mtu(struct qib_pportdata *ppd, u16 arg)
600 {
601 	u32 piosize;
602 	int ret, chk;
603 
604 	if (arg != 256 && arg != 512 && arg != 1024 && arg != 2048 &&
605 	    arg != 4096) {
606 		ret = -EINVAL;
607 		goto bail;
608 	}
609 	chk = ib_mtu_enum_to_int(qib_ibmtu);
610 	if (chk > 0 && arg > chk) {
611 		ret = -EINVAL;
612 		goto bail;
613 	}
614 
615 	piosize = ppd->ibmaxlen;
616 	ppd->ibmtu = arg;
617 
618 	if (arg >= (piosize - QIB_PIO_MAXIBHDR)) {
619 		/* Only if it's not the initial value (or reset to it) */
620 		if (piosize != ppd->init_ibmaxlen) {
621 			if (arg > piosize && arg <= ppd->init_ibmaxlen)
622 				piosize = ppd->init_ibmaxlen - 2 * sizeof(u32);
623 			ppd->ibmaxlen = piosize;
624 		}
625 	} else if ((arg + QIB_PIO_MAXIBHDR) != ppd->ibmaxlen) {
626 		piosize = arg + QIB_PIO_MAXIBHDR - 2 * sizeof(u32);
627 		ppd->ibmaxlen = piosize;
628 	}
629 
630 	ppd->dd->f_set_ib_cfg(ppd, QIB_IB_CFG_MTU, 0);
631 
632 	ret = 0;
633 
634 bail:
635 	return ret;
636 }
637 
638 int qib_set_lid(struct qib_pportdata *ppd, u32 lid, u8 lmc)
639 {
640 	struct qib_devdata *dd = ppd->dd;
641 
642 	ppd->lid = lid;
643 	ppd->lmc = lmc;
644 
645 	dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LIDLMC,
646 			 lid | (~((1U << lmc) - 1)) << 16);
647 
648 	qib_devinfo(dd->pcidev, "IB%u:%u got a lid: 0x%x\n",
649 		    dd->unit, ppd->port, lid);
650 
651 	return 0;
652 }
653 
654 /*
655  * Following deal with the "obviously simple" task of overriding the state
656  * of the LEDS, which normally indicate link physical and logical status.
657  * The complications arise in dealing with different hardware mappings
658  * and the board-dependent routine being called from interrupts.
659  * and then there's the requirement to _flash_ them.
660  */
661 #define LED_OVER_FREQ_SHIFT 8
662 #define LED_OVER_FREQ_MASK (0xFF<<LED_OVER_FREQ_SHIFT)
663 /* Below is "non-zero" to force override, but both actual LEDs are off */
664 #define LED_OVER_BOTH_OFF (8)
665 
666 static void qib_run_led_override(struct timer_list *t)
667 {
668 	struct qib_pportdata *ppd = from_timer(ppd, t,
669 						    led_override_timer);
670 	struct qib_devdata *dd = ppd->dd;
671 	int timeoff;
672 	int ph_idx;
673 
674 	if (!(dd->flags & QIB_INITTED))
675 		return;
676 
677 	ph_idx = ppd->led_override_phase++ & 1;
678 	ppd->led_override = ppd->led_override_vals[ph_idx];
679 	timeoff = ppd->led_override_timeoff;
680 
681 	dd->f_setextled(ppd, 1);
682 	/*
683 	 * don't re-fire the timer if user asked for it to be off; we let
684 	 * it fire one more time after they turn it off to simplify
685 	 */
686 	if (ppd->led_override_vals[0] || ppd->led_override_vals[1])
687 		mod_timer(&ppd->led_override_timer, jiffies + timeoff);
688 }
689 
690 void qib_set_led_override(struct qib_pportdata *ppd, unsigned int val)
691 {
692 	struct qib_devdata *dd = ppd->dd;
693 	int timeoff, freq;
694 
695 	if (!(dd->flags & QIB_INITTED))
696 		return;
697 
698 	/* First check if we are blinking. If not, use 1HZ polling */
699 	timeoff = HZ;
700 	freq = (val & LED_OVER_FREQ_MASK) >> LED_OVER_FREQ_SHIFT;
701 
702 	if (freq) {
703 		/* For blink, set each phase from one nybble of val */
704 		ppd->led_override_vals[0] = val & 0xF;
705 		ppd->led_override_vals[1] = (val >> 4) & 0xF;
706 		timeoff = (HZ << 4)/freq;
707 	} else {
708 		/* Non-blink set both phases the same. */
709 		ppd->led_override_vals[0] = val & 0xF;
710 		ppd->led_override_vals[1] = val & 0xF;
711 	}
712 	ppd->led_override_timeoff = timeoff;
713 
714 	/*
715 	 * If the timer has not already been started, do so. Use a "quick"
716 	 * timeout so the function will be called soon, to look at our request.
717 	 */
718 	if (atomic_inc_return(&ppd->led_override_timer_active) == 1) {
719 		/* Need to start timer */
720 		timer_setup(&ppd->led_override_timer, qib_run_led_override, 0);
721 		ppd->led_override_timer.expires = jiffies + 1;
722 		add_timer(&ppd->led_override_timer);
723 	} else {
724 		if (ppd->led_override_vals[0] || ppd->led_override_vals[1])
725 			mod_timer(&ppd->led_override_timer, jiffies + 1);
726 		atomic_dec(&ppd->led_override_timer_active);
727 	}
728 }
729 
730 /**
731  * qib_reset_device - reset the chip if possible
732  * @unit: the device to reset
733  *
734  * Whether or not reset is successful, we attempt to re-initialize the chip
735  * (that is, much like a driver unload/reload).  We clear the INITTED flag
736  * so that the various entry points will fail until we reinitialize.  For
737  * now, we only allow this if no user contexts are open that use chip resources
738  */
739 int qib_reset_device(int unit)
740 {
741 	int ret, i;
742 	struct qib_devdata *dd = qib_lookup(unit);
743 	struct qib_pportdata *ppd;
744 	unsigned long flags;
745 	int pidx;
746 
747 	if (!dd) {
748 		ret = -ENODEV;
749 		goto bail;
750 	}
751 
752 	qib_devinfo(dd->pcidev, "Reset on unit %u requested\n", unit);
753 
754 	if (!dd->kregbase || !(dd->flags & QIB_PRESENT)) {
755 		qib_devinfo(dd->pcidev,
756 			"Invalid unit number %u or not initialized or not present\n",
757 			unit);
758 		ret = -ENXIO;
759 		goto bail;
760 	}
761 
762 	spin_lock_irqsave(&dd->uctxt_lock, flags);
763 	if (dd->rcd)
764 		for (i = dd->first_user_ctxt; i < dd->cfgctxts; i++) {
765 			if (!dd->rcd[i] || !dd->rcd[i]->cnt)
766 				continue;
767 			spin_unlock_irqrestore(&dd->uctxt_lock, flags);
768 			ret = -EBUSY;
769 			goto bail;
770 		}
771 	spin_unlock_irqrestore(&dd->uctxt_lock, flags);
772 
773 	for (pidx = 0; pidx < dd->num_pports; ++pidx) {
774 		ppd = dd->pport + pidx;
775 		if (atomic_read(&ppd->led_override_timer_active)) {
776 			/* Need to stop LED timer, _then_ shut off LEDs */
777 			del_timer_sync(&ppd->led_override_timer);
778 			atomic_set(&ppd->led_override_timer_active, 0);
779 		}
780 
781 		/* Shut off LEDs after we are sure timer is not running */
782 		ppd->led_override = LED_OVER_BOTH_OFF;
783 		dd->f_setextled(ppd, 0);
784 		if (dd->flags & QIB_HAS_SEND_DMA)
785 			qib_teardown_sdma(ppd);
786 	}
787 
788 	ret = dd->f_reset(dd);
789 	if (ret == 1)
790 		ret = qib_init(dd, 1);
791 	else
792 		ret = -EAGAIN;
793 	if (ret)
794 		qib_dev_err(dd,
795 			"Reinitialize unit %u after reset failed with %d\n",
796 			unit, ret);
797 	else
798 		qib_devinfo(dd->pcidev,
799 			"Reinitialized unit %u after resetting\n",
800 			unit);
801 
802 bail:
803 	return ret;
804 }
805