1 /*
2  * Copyright (c) 2013 Intel Corporation. All rights reserved.
3  * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
4  * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 
35 #include <linux/spinlock.h>
36 #include <linux/pci.h>
37 #include <linux/io.h>
38 #include <linux/delay.h>
39 #include <linux/netdevice.h>
40 #include <linux/vmalloc.h>
41 #include <linux/module.h>
42 #include <linux/prefetch.h>
43 
44 #include "qib.h"
45 
46 /*
47  * The size has to be longer than this string, so we can append
48  * board/chip information to it in the init code.
49  */
50 const char ib_qib_version[] = QIB_DRIVER_VERSION "\n";
51 
52 DEFINE_SPINLOCK(qib_devs_lock);
53 LIST_HEAD(qib_dev_list);
54 DEFINE_MUTEX(qib_mutex);	/* general driver use */
55 
56 unsigned qib_ibmtu;
57 module_param_named(ibmtu, qib_ibmtu, uint, S_IRUGO);
58 MODULE_PARM_DESC(ibmtu, "Set max IB MTU (0=2KB, 1=256, 2=512, ... 5=4096");
59 
60 unsigned qib_compat_ddr_negotiate = 1;
61 module_param_named(compat_ddr_negotiate, qib_compat_ddr_negotiate, uint,
62 		   S_IWUSR | S_IRUGO);
63 MODULE_PARM_DESC(compat_ddr_negotiate,
64 		 "Attempt pre-IBTA 1.2 DDR speed negotiation");
65 
66 MODULE_LICENSE("Dual BSD/GPL");
67 MODULE_AUTHOR("Intel <ibsupport@intel.com>");
68 MODULE_DESCRIPTION("Intel IB driver");
69 
70 /*
71  * QIB_PIO_MAXIBHDR is the max IB header size allowed for in our
72  * PIO send buffers.  This is well beyond anything currently
73  * defined in the InfiniBand spec.
74  */
75 #define QIB_PIO_MAXIBHDR 128
76 
77 /*
78  * QIB_MAX_PKT_RCV is the max # if packets processed per receive interrupt.
79  */
80 #define QIB_MAX_PKT_RECV 64
81 
82 struct qlogic_ib_stats qib_stats;
83 
84 struct pci_dev *qib_get_pci_dev(struct rvt_dev_info *rdi)
85 {
86 	struct qib_ibdev *ibdev = container_of(rdi, struct qib_ibdev, rdi);
87 	struct qib_devdata *dd = container_of(ibdev,
88 					      struct qib_devdata, verbs_dev);
89 	return dd->pcidev;
90 }
91 
92 /*
93  * Return count of units with at least one port ACTIVE.
94  */
95 int qib_count_active_units(void)
96 {
97 	struct qib_devdata *dd;
98 	struct qib_pportdata *ppd;
99 	unsigned long flags;
100 	int pidx, nunits_active = 0;
101 
102 	spin_lock_irqsave(&qib_devs_lock, flags);
103 	list_for_each_entry(dd, &qib_dev_list, list) {
104 		if (!(dd->flags & QIB_PRESENT) || !dd->kregbase)
105 			continue;
106 		for (pidx = 0; pidx < dd->num_pports; ++pidx) {
107 			ppd = dd->pport + pidx;
108 			if (ppd->lid && (ppd->lflags & (QIBL_LINKINIT |
109 					 QIBL_LINKARMED | QIBL_LINKACTIVE))) {
110 				nunits_active++;
111 				break;
112 			}
113 		}
114 	}
115 	spin_unlock_irqrestore(&qib_devs_lock, flags);
116 	return nunits_active;
117 }
118 
119 /*
120  * Return count of all units, optionally return in arguments
121  * the number of usable (present) units, and the number of
122  * ports that are up.
123  */
124 int qib_count_units(int *npresentp, int *nupp)
125 {
126 	int nunits = 0, npresent = 0, nup = 0;
127 	struct qib_devdata *dd;
128 	unsigned long flags;
129 	int pidx;
130 	struct qib_pportdata *ppd;
131 
132 	spin_lock_irqsave(&qib_devs_lock, flags);
133 
134 	list_for_each_entry(dd, &qib_dev_list, list) {
135 		nunits++;
136 		if ((dd->flags & QIB_PRESENT) && dd->kregbase)
137 			npresent++;
138 		for (pidx = 0; pidx < dd->num_pports; ++pidx) {
139 			ppd = dd->pport + pidx;
140 			if (ppd->lid && (ppd->lflags & (QIBL_LINKINIT |
141 					 QIBL_LINKARMED | QIBL_LINKACTIVE)))
142 				nup++;
143 		}
144 	}
145 
146 	spin_unlock_irqrestore(&qib_devs_lock, flags);
147 
148 	if (npresentp)
149 		*npresentp = npresent;
150 	if (nupp)
151 		*nupp = nup;
152 
153 	return nunits;
154 }
155 
156 /**
157  * qib_wait_linkstate - wait for an IB link state change to occur
158  * @dd: the qlogic_ib device
159  * @state: the state to wait for
160  * @msecs: the number of milliseconds to wait
161  *
162  * wait up to msecs milliseconds for IB link state change to occur for
163  * now, take the easy polling route.  Currently used only by
164  * qib_set_linkstate.  Returns 0 if state reached, otherwise
165  * -ETIMEDOUT state can have multiple states set, for any of several
166  * transitions.
167  */
168 int qib_wait_linkstate(struct qib_pportdata *ppd, u32 state, int msecs)
169 {
170 	int ret;
171 	unsigned long flags;
172 
173 	spin_lock_irqsave(&ppd->lflags_lock, flags);
174 	if (ppd->state_wanted) {
175 		spin_unlock_irqrestore(&ppd->lflags_lock, flags);
176 		ret = -EBUSY;
177 		goto bail;
178 	}
179 	ppd->state_wanted = state;
180 	spin_unlock_irqrestore(&ppd->lflags_lock, flags);
181 	wait_event_interruptible_timeout(ppd->state_wait,
182 					 (ppd->lflags & state),
183 					 msecs_to_jiffies(msecs));
184 	spin_lock_irqsave(&ppd->lflags_lock, flags);
185 	ppd->state_wanted = 0;
186 	spin_unlock_irqrestore(&ppd->lflags_lock, flags);
187 
188 	if (!(ppd->lflags & state))
189 		ret = -ETIMEDOUT;
190 	else
191 		ret = 0;
192 bail:
193 	return ret;
194 }
195 
196 int qib_set_linkstate(struct qib_pportdata *ppd, u8 newstate)
197 {
198 	u32 lstate;
199 	int ret;
200 	struct qib_devdata *dd = ppd->dd;
201 	unsigned long flags;
202 
203 	switch (newstate) {
204 	case QIB_IB_LINKDOWN_ONLY:
205 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
206 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_NOP);
207 		/* don't wait */
208 		ret = 0;
209 		goto bail;
210 
211 	case QIB_IB_LINKDOWN:
212 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
213 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_POLL);
214 		/* don't wait */
215 		ret = 0;
216 		goto bail;
217 
218 	case QIB_IB_LINKDOWN_SLEEP:
219 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
220 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_SLEEP);
221 		/* don't wait */
222 		ret = 0;
223 		goto bail;
224 
225 	case QIB_IB_LINKDOWN_DISABLE:
226 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
227 				 IB_LINKCMD_DOWN | IB_LINKINITCMD_DISABLE);
228 		/* don't wait */
229 		ret = 0;
230 		goto bail;
231 
232 	case QIB_IB_LINKARM:
233 		if (ppd->lflags & QIBL_LINKARMED) {
234 			ret = 0;
235 			goto bail;
236 		}
237 		if (!(ppd->lflags & (QIBL_LINKINIT | QIBL_LINKACTIVE))) {
238 			ret = -EINVAL;
239 			goto bail;
240 		}
241 		/*
242 		 * Since the port can be ACTIVE when we ask for ARMED,
243 		 * clear QIBL_LINKV so we can wait for a transition.
244 		 * If the link isn't ARMED, then something else happened
245 		 * and there is no point waiting for ARMED.
246 		 */
247 		spin_lock_irqsave(&ppd->lflags_lock, flags);
248 		ppd->lflags &= ~QIBL_LINKV;
249 		spin_unlock_irqrestore(&ppd->lflags_lock, flags);
250 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
251 				 IB_LINKCMD_ARMED | IB_LINKINITCMD_NOP);
252 		lstate = QIBL_LINKV;
253 		break;
254 
255 	case QIB_IB_LINKACTIVE:
256 		if (ppd->lflags & QIBL_LINKACTIVE) {
257 			ret = 0;
258 			goto bail;
259 		}
260 		if (!(ppd->lflags & QIBL_LINKARMED)) {
261 			ret = -EINVAL;
262 			goto bail;
263 		}
264 		dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LSTATE,
265 				 IB_LINKCMD_ACTIVE | IB_LINKINITCMD_NOP);
266 		lstate = QIBL_LINKACTIVE;
267 		break;
268 
269 	default:
270 		ret = -EINVAL;
271 		goto bail;
272 	}
273 	ret = qib_wait_linkstate(ppd, lstate, 10);
274 
275 bail:
276 	return ret;
277 }
278 
279 /*
280  * Get address of eager buffer from it's index (allocated in chunks, not
281  * contiguous).
282  */
283 static inline void *qib_get_egrbuf(const struct qib_ctxtdata *rcd, u32 etail)
284 {
285 	const u32 chunk = etail >> rcd->rcvegrbufs_perchunk_shift;
286 	const u32 idx =  etail & ((u32)rcd->rcvegrbufs_perchunk - 1);
287 
288 	return rcd->rcvegrbuf[chunk] + (idx << rcd->dd->rcvegrbufsize_shift);
289 }
290 
291 /*
292  * Returns 1 if error was a CRC, else 0.
293  * Needed for some chip's synthesized error counters.
294  */
295 static u32 qib_rcv_hdrerr(struct qib_ctxtdata *rcd, struct qib_pportdata *ppd,
296 			  u32 ctxt, u32 eflags, u32 l, u32 etail,
297 			  __le32 *rhf_addr, struct qib_message_header *rhdr)
298 {
299 	u32 ret = 0;
300 
301 	if (eflags & (QLOGIC_IB_RHF_H_ICRCERR | QLOGIC_IB_RHF_H_VCRCERR))
302 		ret = 1;
303 	else if (eflags == QLOGIC_IB_RHF_H_TIDERR) {
304 		/* For TIDERR and RC QPs premptively schedule a NAK */
305 		struct ib_header *hdr = (struct ib_header *)rhdr;
306 		struct ib_other_headers *ohdr = NULL;
307 		struct qib_ibport *ibp = &ppd->ibport_data;
308 		struct qib_devdata *dd = ppd->dd;
309 		struct rvt_dev_info *rdi = &dd->verbs_dev.rdi;
310 		struct rvt_qp *qp = NULL;
311 		u32 tlen = qib_hdrget_length_in_bytes(rhf_addr);
312 		u16 lid  = be16_to_cpu(hdr->lrh[1]);
313 		int lnh = be16_to_cpu(hdr->lrh[0]) & 3;
314 		u32 qp_num;
315 		u32 opcode;
316 		u32 psn;
317 		int diff;
318 
319 		/* Sanity check packet */
320 		if (tlen < 24)
321 			goto drop;
322 
323 		if (lid < be16_to_cpu(IB_MULTICAST_LID_BASE)) {
324 			lid &= ~((1 << ppd->lmc) - 1);
325 			if (unlikely(lid != ppd->lid))
326 				goto drop;
327 		}
328 
329 		/* Check for GRH */
330 		if (lnh == QIB_LRH_BTH)
331 			ohdr = &hdr->u.oth;
332 		else if (lnh == QIB_LRH_GRH) {
333 			u32 vtf;
334 
335 			ohdr = &hdr->u.l.oth;
336 			if (hdr->u.l.grh.next_hdr != IB_GRH_NEXT_HDR)
337 				goto drop;
338 			vtf = be32_to_cpu(hdr->u.l.grh.version_tclass_flow);
339 			if ((vtf >> IB_GRH_VERSION_SHIFT) != IB_GRH_VERSION)
340 				goto drop;
341 		} else
342 			goto drop;
343 
344 		/* Get opcode and PSN from packet */
345 		opcode = be32_to_cpu(ohdr->bth[0]);
346 		opcode >>= 24;
347 		psn = be32_to_cpu(ohdr->bth[2]);
348 
349 		/* Get the destination QP number. */
350 		qp_num = be32_to_cpu(ohdr->bth[1]) & RVT_QPN_MASK;
351 		if (qp_num != QIB_MULTICAST_QPN) {
352 			int ruc_res;
353 
354 			rcu_read_lock();
355 			qp = rvt_lookup_qpn(rdi, &ibp->rvp, qp_num);
356 			if (!qp) {
357 				rcu_read_unlock();
358 				goto drop;
359 			}
360 
361 			/*
362 			 * Handle only RC QPs - for other QP types drop error
363 			 * packet.
364 			 */
365 			spin_lock(&qp->r_lock);
366 
367 			/* Check for valid receive state. */
368 			if (!(ib_rvt_state_ops[qp->state] &
369 			      RVT_PROCESS_RECV_OK)) {
370 				ibp->rvp.n_pkt_drops++;
371 				goto unlock;
372 			}
373 
374 			switch (qp->ibqp.qp_type) {
375 			case IB_QPT_RC:
376 				ruc_res =
377 					qib_ruc_check_hdr(
378 						ibp, hdr,
379 						lnh == QIB_LRH_GRH,
380 						qp,
381 						be32_to_cpu(ohdr->bth[0]));
382 				if (ruc_res)
383 					goto unlock;
384 
385 				/* Only deal with RDMA Writes for now */
386 				if (opcode <
387 				    IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) {
388 					diff = qib_cmp24(psn, qp->r_psn);
389 					if (!qp->r_nak_state && diff >= 0) {
390 						ibp->rvp.n_rc_seqnak++;
391 						qp->r_nak_state =
392 							IB_NAK_PSN_ERROR;
393 						/* Use the expected PSN. */
394 						qp->r_ack_psn = qp->r_psn;
395 						/*
396 						 * Wait to send the sequence
397 						 * NAK until all packets
398 						 * in the receive queue have
399 						 * been processed.
400 						 * Otherwise, we end up
401 						 * propagating congestion.
402 						 */
403 						if (list_empty(&qp->rspwait)) {
404 							qp->r_flags |=
405 								RVT_R_RSP_NAK;
406 							rvt_get_qp(qp);
407 							list_add_tail(
408 							 &qp->rspwait,
409 							 &rcd->qp_wait_list);
410 						}
411 					} /* Out of sequence NAK */
412 				} /* QP Request NAKs */
413 				break;
414 			case IB_QPT_SMI:
415 			case IB_QPT_GSI:
416 			case IB_QPT_UD:
417 			case IB_QPT_UC:
418 			default:
419 				/* For now don't handle any other QP types */
420 				break;
421 			}
422 
423 unlock:
424 			spin_unlock(&qp->r_lock);
425 			rcu_read_unlock();
426 		} /* Unicast QP */
427 	} /* Valid packet with TIDErr */
428 
429 drop:
430 	return ret;
431 }
432 
433 /*
434  * qib_kreceive - receive a packet
435  * @rcd: the qlogic_ib context
436  * @llic: gets count of good packets needed to clear lli,
437  *          (used with chips that need need to track crcs for lli)
438  *
439  * called from interrupt handler for errors or receive interrupt
440  * Returns number of CRC error packets, needed by some chips for
441  * local link integrity tracking.   crcs are adjusted down by following
442  * good packets, if any, and count of good packets is also tracked.
443  */
444 u32 qib_kreceive(struct qib_ctxtdata *rcd, u32 *llic, u32 *npkts)
445 {
446 	struct qib_devdata *dd = rcd->dd;
447 	struct qib_pportdata *ppd = rcd->ppd;
448 	__le32 *rhf_addr;
449 	void *ebuf;
450 	const u32 rsize = dd->rcvhdrentsize;        /* words */
451 	const u32 maxcnt = dd->rcvhdrcnt * rsize;   /* words */
452 	u32 etail = -1, l, hdrqtail;
453 	struct qib_message_header *hdr;
454 	u32 eflags, etype, tlen, i = 0, updegr = 0, crcs = 0;
455 	int last;
456 	u64 lval;
457 	struct rvt_qp *qp, *nqp;
458 
459 	l = rcd->head;
460 	rhf_addr = (__le32 *) rcd->rcvhdrq + l + dd->rhf_offset;
461 	if (dd->flags & QIB_NODMA_RTAIL) {
462 		u32 seq = qib_hdrget_seq(rhf_addr);
463 
464 		if (seq != rcd->seq_cnt)
465 			goto bail;
466 		hdrqtail = 0;
467 	} else {
468 		hdrqtail = qib_get_rcvhdrtail(rcd);
469 		if (l == hdrqtail)
470 			goto bail;
471 		smp_rmb();  /* prevent speculative reads of dma'ed hdrq */
472 	}
473 
474 	for (last = 0, i = 1; !last; i += !last) {
475 		hdr = dd->f_get_msgheader(dd, rhf_addr);
476 		eflags = qib_hdrget_err_flags(rhf_addr);
477 		etype = qib_hdrget_rcv_type(rhf_addr);
478 		/* total length */
479 		tlen = qib_hdrget_length_in_bytes(rhf_addr);
480 		ebuf = NULL;
481 		if ((dd->flags & QIB_NODMA_RTAIL) ?
482 		    qib_hdrget_use_egr_buf(rhf_addr) :
483 		    (etype != RCVHQ_RCV_TYPE_EXPECTED)) {
484 			etail = qib_hdrget_index(rhf_addr);
485 			updegr = 1;
486 			if (tlen > sizeof(*hdr) ||
487 			    etype >= RCVHQ_RCV_TYPE_NON_KD) {
488 				ebuf = qib_get_egrbuf(rcd, etail);
489 				prefetch_range(ebuf, tlen - sizeof(*hdr));
490 			}
491 		}
492 		if (!eflags) {
493 			u16 lrh_len = be16_to_cpu(hdr->lrh[2]) << 2;
494 
495 			if (lrh_len != tlen) {
496 				qib_stats.sps_lenerrs++;
497 				goto move_along;
498 			}
499 		}
500 		if (etype == RCVHQ_RCV_TYPE_NON_KD && !eflags &&
501 		    ebuf == NULL &&
502 		    tlen > (dd->rcvhdrentsize - 2 + 1 -
503 				qib_hdrget_offset(rhf_addr)) << 2) {
504 			goto move_along;
505 		}
506 
507 		/*
508 		 * Both tiderr and qibhdrerr are set for all plain IB
509 		 * packets; only qibhdrerr should be set.
510 		 */
511 		if (unlikely(eflags))
512 			crcs += qib_rcv_hdrerr(rcd, ppd, rcd->ctxt, eflags, l,
513 					       etail, rhf_addr, hdr);
514 		else if (etype == RCVHQ_RCV_TYPE_NON_KD) {
515 			qib_ib_rcv(rcd, hdr, ebuf, tlen);
516 			if (crcs)
517 				crcs--;
518 			else if (llic && *llic)
519 				--*llic;
520 		}
521 move_along:
522 		l += rsize;
523 		if (l >= maxcnt)
524 			l = 0;
525 		if (i == QIB_MAX_PKT_RECV)
526 			last = 1;
527 
528 		rhf_addr = (__le32 *) rcd->rcvhdrq + l + dd->rhf_offset;
529 		if (dd->flags & QIB_NODMA_RTAIL) {
530 			u32 seq = qib_hdrget_seq(rhf_addr);
531 
532 			if (++rcd->seq_cnt > 13)
533 				rcd->seq_cnt = 1;
534 			if (seq != rcd->seq_cnt)
535 				last = 1;
536 		} else if (l == hdrqtail)
537 			last = 1;
538 		/*
539 		 * Update head regs etc., every 16 packets, if not last pkt,
540 		 * to help prevent rcvhdrq overflows, when many packets
541 		 * are processed and queue is nearly full.
542 		 * Don't request an interrupt for intermediate updates.
543 		 */
544 		lval = l;
545 		if (!last && !(i & 0xf)) {
546 			dd->f_update_usrhead(rcd, lval, updegr, etail, i);
547 			updegr = 0;
548 		}
549 	}
550 
551 	rcd->head = l;
552 
553 	/*
554 	 * Iterate over all QPs waiting to respond.
555 	 * The list won't change since the IRQ is only run on one CPU.
556 	 */
557 	list_for_each_entry_safe(qp, nqp, &rcd->qp_wait_list, rspwait) {
558 		list_del_init(&qp->rspwait);
559 		if (qp->r_flags & RVT_R_RSP_NAK) {
560 			qp->r_flags &= ~RVT_R_RSP_NAK;
561 			qib_send_rc_ack(qp);
562 		}
563 		if (qp->r_flags & RVT_R_RSP_SEND) {
564 			unsigned long flags;
565 
566 			qp->r_flags &= ~RVT_R_RSP_SEND;
567 			spin_lock_irqsave(&qp->s_lock, flags);
568 			if (ib_rvt_state_ops[qp->state] &
569 					RVT_PROCESS_OR_FLUSH_SEND)
570 				qib_schedule_send(qp);
571 			spin_unlock_irqrestore(&qp->s_lock, flags);
572 		}
573 		rvt_put_qp(qp);
574 	}
575 
576 bail:
577 	/* Report number of packets consumed */
578 	if (npkts)
579 		*npkts = i;
580 
581 	/*
582 	 * Always write head at end, and setup rcv interrupt, even
583 	 * if no packets were processed.
584 	 */
585 	lval = (u64)rcd->head | dd->rhdrhead_intr_off;
586 	dd->f_update_usrhead(rcd, lval, updegr, etail, i);
587 	return crcs;
588 }
589 
590 /**
591  * qib_set_mtu - set the MTU
592  * @ppd: the perport data
593  * @arg: the new MTU
594  *
595  * We can handle "any" incoming size, the issue here is whether we
596  * need to restrict our outgoing size.   For now, we don't do any
597  * sanity checking on this, and we don't deal with what happens to
598  * programs that are already running when the size changes.
599  * NOTE: changing the MTU will usually cause the IBC to go back to
600  * link INIT state...
601  */
602 int qib_set_mtu(struct qib_pportdata *ppd, u16 arg)
603 {
604 	u32 piosize;
605 	int ret, chk;
606 
607 	if (arg != 256 && arg != 512 && arg != 1024 && arg != 2048 &&
608 	    arg != 4096) {
609 		ret = -EINVAL;
610 		goto bail;
611 	}
612 	chk = ib_mtu_enum_to_int(qib_ibmtu);
613 	if (chk > 0 && arg > chk) {
614 		ret = -EINVAL;
615 		goto bail;
616 	}
617 
618 	piosize = ppd->ibmaxlen;
619 	ppd->ibmtu = arg;
620 
621 	if (arg >= (piosize - QIB_PIO_MAXIBHDR)) {
622 		/* Only if it's not the initial value (or reset to it) */
623 		if (piosize != ppd->init_ibmaxlen) {
624 			if (arg > piosize && arg <= ppd->init_ibmaxlen)
625 				piosize = ppd->init_ibmaxlen - 2 * sizeof(u32);
626 			ppd->ibmaxlen = piosize;
627 		}
628 	} else if ((arg + QIB_PIO_MAXIBHDR) != ppd->ibmaxlen) {
629 		piosize = arg + QIB_PIO_MAXIBHDR - 2 * sizeof(u32);
630 		ppd->ibmaxlen = piosize;
631 	}
632 
633 	ppd->dd->f_set_ib_cfg(ppd, QIB_IB_CFG_MTU, 0);
634 
635 	ret = 0;
636 
637 bail:
638 	return ret;
639 }
640 
641 int qib_set_lid(struct qib_pportdata *ppd, u32 lid, u8 lmc)
642 {
643 	struct qib_devdata *dd = ppd->dd;
644 
645 	ppd->lid = lid;
646 	ppd->lmc = lmc;
647 
648 	dd->f_set_ib_cfg(ppd, QIB_IB_CFG_LIDLMC,
649 			 lid | (~((1U << lmc) - 1)) << 16);
650 
651 	qib_devinfo(dd->pcidev, "IB%u:%u got a lid: 0x%x\n",
652 		    dd->unit, ppd->port, lid);
653 
654 	return 0;
655 }
656 
657 /*
658  * Following deal with the "obviously simple" task of overriding the state
659  * of the LEDS, which normally indicate link physical and logical status.
660  * The complications arise in dealing with different hardware mappings
661  * and the board-dependent routine being called from interrupts.
662  * and then there's the requirement to _flash_ them.
663  */
664 #define LED_OVER_FREQ_SHIFT 8
665 #define LED_OVER_FREQ_MASK (0xFF<<LED_OVER_FREQ_SHIFT)
666 /* Below is "non-zero" to force override, but both actual LEDs are off */
667 #define LED_OVER_BOTH_OFF (8)
668 
669 static void qib_run_led_override(struct timer_list *t)
670 {
671 	struct qib_pportdata *ppd = from_timer(ppd, t,
672 						    led_override_timer);
673 	struct qib_devdata *dd = ppd->dd;
674 	int timeoff;
675 	int ph_idx;
676 
677 	if (!(dd->flags & QIB_INITTED))
678 		return;
679 
680 	ph_idx = ppd->led_override_phase++ & 1;
681 	ppd->led_override = ppd->led_override_vals[ph_idx];
682 	timeoff = ppd->led_override_timeoff;
683 
684 	dd->f_setextled(ppd, 1);
685 	/*
686 	 * don't re-fire the timer if user asked for it to be off; we let
687 	 * it fire one more time after they turn it off to simplify
688 	 */
689 	if (ppd->led_override_vals[0] || ppd->led_override_vals[1])
690 		mod_timer(&ppd->led_override_timer, jiffies + timeoff);
691 }
692 
693 void qib_set_led_override(struct qib_pportdata *ppd, unsigned int val)
694 {
695 	struct qib_devdata *dd = ppd->dd;
696 	int timeoff, freq;
697 
698 	if (!(dd->flags & QIB_INITTED))
699 		return;
700 
701 	/* First check if we are blinking. If not, use 1HZ polling */
702 	timeoff = HZ;
703 	freq = (val & LED_OVER_FREQ_MASK) >> LED_OVER_FREQ_SHIFT;
704 
705 	if (freq) {
706 		/* For blink, set each phase from one nybble of val */
707 		ppd->led_override_vals[0] = val & 0xF;
708 		ppd->led_override_vals[1] = (val >> 4) & 0xF;
709 		timeoff = (HZ << 4)/freq;
710 	} else {
711 		/* Non-blink set both phases the same. */
712 		ppd->led_override_vals[0] = val & 0xF;
713 		ppd->led_override_vals[1] = val & 0xF;
714 	}
715 	ppd->led_override_timeoff = timeoff;
716 
717 	/*
718 	 * If the timer has not already been started, do so. Use a "quick"
719 	 * timeout so the function will be called soon, to look at our request.
720 	 */
721 	if (atomic_inc_return(&ppd->led_override_timer_active) == 1) {
722 		/* Need to start timer */
723 		timer_setup(&ppd->led_override_timer, qib_run_led_override, 0);
724 		ppd->led_override_timer.expires = jiffies + 1;
725 		add_timer(&ppd->led_override_timer);
726 	} else {
727 		if (ppd->led_override_vals[0] || ppd->led_override_vals[1])
728 			mod_timer(&ppd->led_override_timer, jiffies + 1);
729 		atomic_dec(&ppd->led_override_timer_active);
730 	}
731 }
732 
733 /**
734  * qib_reset_device - reset the chip if possible
735  * @unit: the device to reset
736  *
737  * Whether or not reset is successful, we attempt to re-initialize the chip
738  * (that is, much like a driver unload/reload).  We clear the INITTED flag
739  * so that the various entry points will fail until we reinitialize.  For
740  * now, we only allow this if no user contexts are open that use chip resources
741  */
742 int qib_reset_device(int unit)
743 {
744 	int ret, i;
745 	struct qib_devdata *dd = qib_lookup(unit);
746 	struct qib_pportdata *ppd;
747 	unsigned long flags;
748 	int pidx;
749 
750 	if (!dd) {
751 		ret = -ENODEV;
752 		goto bail;
753 	}
754 
755 	qib_devinfo(dd->pcidev, "Reset on unit %u requested\n", unit);
756 
757 	if (!dd->kregbase || !(dd->flags & QIB_PRESENT)) {
758 		qib_devinfo(dd->pcidev,
759 			"Invalid unit number %u or not initialized or not present\n",
760 			unit);
761 		ret = -ENXIO;
762 		goto bail;
763 	}
764 
765 	spin_lock_irqsave(&dd->uctxt_lock, flags);
766 	if (dd->rcd)
767 		for (i = dd->first_user_ctxt; i < dd->cfgctxts; i++) {
768 			if (!dd->rcd[i] || !dd->rcd[i]->cnt)
769 				continue;
770 			spin_unlock_irqrestore(&dd->uctxt_lock, flags);
771 			ret = -EBUSY;
772 			goto bail;
773 		}
774 	spin_unlock_irqrestore(&dd->uctxt_lock, flags);
775 
776 	for (pidx = 0; pidx < dd->num_pports; ++pidx) {
777 		ppd = dd->pport + pidx;
778 		if (atomic_read(&ppd->led_override_timer_active)) {
779 			/* Need to stop LED timer, _then_ shut off LEDs */
780 			del_timer_sync(&ppd->led_override_timer);
781 			atomic_set(&ppd->led_override_timer_active, 0);
782 		}
783 
784 		/* Shut off LEDs after we are sure timer is not running */
785 		ppd->led_override = LED_OVER_BOTH_OFF;
786 		dd->f_setextled(ppd, 0);
787 		if (dd->flags & QIB_HAS_SEND_DMA)
788 			qib_teardown_sdma(ppd);
789 	}
790 
791 	ret = dd->f_reset(dd);
792 	if (ret == 1)
793 		ret = qib_init(dd, 1);
794 	else
795 		ret = -EAGAIN;
796 	if (ret)
797 		qib_dev_err(dd,
798 			"Reinitialize unit %u after reset failed with %d\n",
799 			unit, ret);
800 	else
801 		qib_devinfo(dd->pcidev,
802 			"Reinitialized unit %u after resetting\n",
803 			unit);
804 
805 bail:
806 	return ret;
807 }
808