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IB/ipath: Misc sparse warning cleanup
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1 /*
2  * Copyright (c) 2006, 2007 QLogic Corporation. All rights reserved.
3  * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *        copyright notice, this list of conditions and the following
17  *        disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer in the documentation and/or other materials
22  *        provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33
34 #include <linux/pci.h>
35
36 #include "ipath_kernel.h"
37 #include "ipath_verbs.h"
38 #include "ipath_common.h"
39
40 /*
41  * clear (write) a pio buffer, to clear a parity error.   This routine
42  * should only be called when in freeze mode, and the buffer should be
43  * canceled afterwards.
44  */
45 static void ipath_clrpiobuf(struct ipath_devdata *dd, u32 pnum)
46 {
47         u32 __iomem *pbuf;
48         u32 dwcnt; /* dword count to write */
49         if (pnum < dd->ipath_piobcnt2k) {
50                 pbuf = (u32 __iomem *) (dd->ipath_pio2kbase + pnum *
51                         dd->ipath_palign);
52                 dwcnt = dd->ipath_piosize2k >> 2;
53         }
54         else {
55                 pbuf = (u32 __iomem *) (dd->ipath_pio4kbase +
56                         (pnum - dd->ipath_piobcnt2k) * dd->ipath_4kalign);
57                 dwcnt = dd->ipath_piosize4k >> 2;
58         }
59         dev_info(&dd->pcidev->dev,
60                 "Rewrite PIO buffer %u, to recover from parity error\n",
61                 pnum);
62
63         /* no flush required, since already in freeze */
64         writel(dwcnt + 1, pbuf);
65         while (--dwcnt)
66                 writel(0, pbuf++);
67 }
68
69 /*
70  * Called when we might have an error that is specific to a particular
71  * PIO buffer, and may need to cancel that buffer, so it can be re-used.
72  * If rewrite is true, and bits are set in the sendbufferror registers,
73  * we'll write to the buffer, for error recovery on parity errors.
74  */
75 static void ipath_disarm_senderrbufs(struct ipath_devdata *dd, int rewrite)
76 {
77         u32 piobcnt;
78         unsigned long sbuf[4];
79         /*
80          * it's possible that sendbuffererror could have bits set; might
81          * have already done this as a result of hardware error handling
82          */
83         piobcnt = dd->ipath_piobcnt2k + dd->ipath_piobcnt4k;
84         /* read these before writing errorclear */
85         sbuf[0] = ipath_read_kreg64(
86                 dd, dd->ipath_kregs->kr_sendbuffererror);
87         sbuf[1] = ipath_read_kreg64(
88                 dd, dd->ipath_kregs->kr_sendbuffererror + 1);
89         if (piobcnt > 128) {
90                 sbuf[2] = ipath_read_kreg64(
91                         dd, dd->ipath_kregs->kr_sendbuffererror + 2);
92                 sbuf[3] = ipath_read_kreg64(
93                         dd, dd->ipath_kregs->kr_sendbuffererror + 3);
94         }
95
96         if (sbuf[0] || sbuf[1] || (piobcnt > 128 && (sbuf[2] || sbuf[3]))) {
97                 int i;
98                 if (ipath_debug & (__IPATH_PKTDBG|__IPATH_DBG) &&
99                         dd->ipath_lastcancel > jiffies) {
100                         __IPATH_DBG_WHICH(__IPATH_PKTDBG|__IPATH_DBG,
101                                           "SendbufErrs %lx %lx", sbuf[0],
102                                           sbuf[1]);
103                         if (ipath_debug & __IPATH_PKTDBG && piobcnt > 128)
104                                 printk(" %lx %lx ", sbuf[2], sbuf[3]);
105                         printk("\n");
106                 }
107
108                 for (i = 0; i < piobcnt; i++)
109                         if (test_bit(i, sbuf)) {
110                                 if (rewrite)
111                                         ipath_clrpiobuf(dd, i);
112                                 ipath_disarm_piobufs(dd, i, 1);
113                         }
114                 /* ignore armlaunch errs for a bit */
115                 dd->ipath_lastcancel = jiffies+3;
116         }
117 }
118
119
120 /* These are all rcv-related errors which we want to count for stats */
121 #define E_SUM_PKTERRS \
122         (INFINIPATH_E_RHDRLEN | INFINIPATH_E_RBADTID | \
123          INFINIPATH_E_RBADVERSION | INFINIPATH_E_RHDR | \
124          INFINIPATH_E_RLONGPKTLEN | INFINIPATH_E_RSHORTPKTLEN | \
125          INFINIPATH_E_RMAXPKTLEN | INFINIPATH_E_RMINPKTLEN | \
126          INFINIPATH_E_RFORMATERR | INFINIPATH_E_RUNSUPVL | \
127          INFINIPATH_E_RUNEXPCHAR | INFINIPATH_E_REBP)
128
129 /* These are all send-related errors which we want to count for stats */
130 #define E_SUM_ERRS \
131         (INFINIPATH_E_SPIOARMLAUNCH | INFINIPATH_E_SUNEXPERRPKTNUM | \
132          INFINIPATH_E_SDROPPEDDATAPKT | INFINIPATH_E_SDROPPEDSMPPKT | \
133          INFINIPATH_E_SMAXPKTLEN | INFINIPATH_E_SUNSUPVL | \
134          INFINIPATH_E_SMINPKTLEN | INFINIPATH_E_SPKTLEN | \
135          INFINIPATH_E_INVALIDADDR)
136
137 /*
138  * this is similar to E_SUM_ERRS, but can't ignore armlaunch, don't ignore
139  * errors not related to freeze and cancelling buffers.  Can't ignore
140  * armlaunch because could get more while still cleaning up, and need
141  * to cancel those as they happen.
142  */
143 #define E_SPKT_ERRS_IGNORE \
144          (INFINIPATH_E_SDROPPEDDATAPKT | INFINIPATH_E_SDROPPEDSMPPKT | \
145          INFINIPATH_E_SMAXPKTLEN | INFINIPATH_E_SMINPKTLEN | \
146          INFINIPATH_E_SPKTLEN)
147
148 /*
149  * these are errors that can occur when the link changes state while
150  * a packet is being sent or received.  This doesn't cover things
151  * like EBP or VCRC that can be the result of a sending having the
152  * link change state, so we receive a "known bad" packet.
153  */
154 #define E_SUM_LINK_PKTERRS \
155         (INFINIPATH_E_SDROPPEDDATAPKT | INFINIPATH_E_SDROPPEDSMPPKT | \
156          INFINIPATH_E_SMINPKTLEN | INFINIPATH_E_SPKTLEN | \
157          INFINIPATH_E_RSHORTPKTLEN | INFINIPATH_E_RMINPKTLEN | \
158          INFINIPATH_E_RUNEXPCHAR)
159
160 static u64 handle_e_sum_errs(struct ipath_devdata *dd, ipath_err_t errs)
161 {
162         u64 ignore_this_time = 0;
163
164         ipath_disarm_senderrbufs(dd, 0);
165         if ((errs & E_SUM_LINK_PKTERRS) &&
166             !(dd->ipath_flags & IPATH_LINKACTIVE)) {
167                 /*
168                  * This can happen when SMA is trying to bring the link
169                  * up, but the IB link changes state at the "wrong" time.
170                  * The IB logic then complains that the packet isn't
171                  * valid.  We don't want to confuse people, so we just
172                  * don't print them, except at debug
173                  */
174                 ipath_dbg("Ignoring packet errors %llx, because link not "
175                           "ACTIVE\n", (unsigned long long) errs);
176                 ignore_this_time = errs & E_SUM_LINK_PKTERRS;
177         }
178
179         return ignore_this_time;
180 }
181
182 /* generic hw error messages... */
183 #define INFINIPATH_HWE_TXEMEMPARITYERR_MSG(a) \
184         { \
185                 .mask = ( INFINIPATH_HWE_TXEMEMPARITYERR_##a <<    \
186                           INFINIPATH_HWE_TXEMEMPARITYERR_SHIFT ),   \
187                 .msg = "TXE " #a " Memory Parity"            \
188         }
189 #define INFINIPATH_HWE_RXEMEMPARITYERR_MSG(a) \
190         { \
191                 .mask = ( INFINIPATH_HWE_RXEMEMPARITYERR_##a <<    \
192                           INFINIPATH_HWE_RXEMEMPARITYERR_SHIFT ),   \
193                 .msg = "RXE " #a " Memory Parity"            \
194         }
195
196 static const struct ipath_hwerror_msgs ipath_generic_hwerror_msgs[] = {
197         INFINIPATH_HWE_MSG(IBCBUSFRSPCPARITYERR, "IPATH2IB Parity"),
198         INFINIPATH_HWE_MSG(IBCBUSTOSPCPARITYERR, "IB2IPATH Parity"),
199
200         INFINIPATH_HWE_TXEMEMPARITYERR_MSG(PIOBUF),
201         INFINIPATH_HWE_TXEMEMPARITYERR_MSG(PIOPBC),
202         INFINIPATH_HWE_TXEMEMPARITYERR_MSG(PIOLAUNCHFIFO),
203
204         INFINIPATH_HWE_RXEMEMPARITYERR_MSG(RCVBUF),
205         INFINIPATH_HWE_RXEMEMPARITYERR_MSG(LOOKUPQ),
206         INFINIPATH_HWE_RXEMEMPARITYERR_MSG(EAGERTID),
207         INFINIPATH_HWE_RXEMEMPARITYERR_MSG(EXPTID),
208         INFINIPATH_HWE_RXEMEMPARITYERR_MSG(FLAGBUF),
209         INFINIPATH_HWE_RXEMEMPARITYERR_MSG(DATAINFO),
210         INFINIPATH_HWE_RXEMEMPARITYERR_MSG(HDRINFO),
211 };
212
213 /**
214  * ipath_format_hwmsg - format a single hwerror message
215  * @msg message buffer
216  * @msgl length of message buffer
217  * @hwmsg message to add to message buffer
218  */
219 static void ipath_format_hwmsg(char *msg, size_t msgl, const char *hwmsg)
220 {
221         strlcat(msg, "[", msgl);
222         strlcat(msg, hwmsg, msgl);
223         strlcat(msg, "]", msgl);
224 }
225
226 /**
227  * ipath_format_hwerrors - format hardware error messages for display
228  * @hwerrs hardware errors bit vector
229  * @hwerrmsgs hardware error descriptions
230  * @nhwerrmsgs number of hwerrmsgs
231  * @msg message buffer
232  * @msgl message buffer length
233  */
234 void ipath_format_hwerrors(u64 hwerrs,
235                            const struct ipath_hwerror_msgs *hwerrmsgs,
236                            size_t nhwerrmsgs,
237                            char *msg, size_t msgl)
238 {
239         int i;
240         const int glen =
241             sizeof(ipath_generic_hwerror_msgs) /
242             sizeof(ipath_generic_hwerror_msgs[0]);
243
244         for (i=0; i<glen; i++) {
245                 if (hwerrs & ipath_generic_hwerror_msgs[i].mask) {
246                         ipath_format_hwmsg(msg, msgl,
247                                            ipath_generic_hwerror_msgs[i].msg);
248                 }
249         }
250
251         for (i=0; i<nhwerrmsgs; i++) {
252                 if (hwerrs & hwerrmsgs[i].mask) {
253                         ipath_format_hwmsg(msg, msgl, hwerrmsgs[i].msg);
254                 }
255         }
256 }
257
258 /* return the strings for the most common link states */
259 static char *ib_linkstate(u32 linkstate)
260 {
261         char *ret;
262
263         switch (linkstate) {
264         case IPATH_IBSTATE_INIT:
265                 ret = "Init";
266                 break;
267         case IPATH_IBSTATE_ARM:
268                 ret = "Arm";
269                 break;
270         case IPATH_IBSTATE_ACTIVE:
271                 ret = "Active";
272                 break;
273         default:
274                 ret = "Down";
275         }
276
277         return ret;
278 }
279
280 void signal_ib_event(struct ipath_devdata *dd, enum ib_event_type ev)
281 {
282         struct ib_event event;
283
284         event.device = &dd->verbs_dev->ibdev;
285         event.element.port_num = 1;
286         event.event = ev;
287         ib_dispatch_event(&event);
288 }
289
290 static void handle_e_ibstatuschanged(struct ipath_devdata *dd,
291                                      ipath_err_t errs, int noprint)
292 {
293         u64 val;
294         u32 ltstate, lstate;
295
296         /*
297          * even if diags are enabled, we want to notice LINKINIT, etc.
298          * We just don't want to change the LED state, or
299          * dd->ipath_kregs->kr_ibcctrl
300          */
301         val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_ibcstatus);
302         lstate = val & IPATH_IBSTATE_MASK;
303
304         /*
305          * this is confusing enough when it happens that I want to always put it
306          * on the console and in the logs.  If it was a requested state change,
307          * we'll have already cleared the flags, so we won't print this warning
308          */
309         if ((lstate != IPATH_IBSTATE_ARM && lstate != IPATH_IBSTATE_ACTIVE)
310                 && (dd->ipath_flags & (IPATH_LINKARMED | IPATH_LINKACTIVE))) {
311                 dev_info(&dd->pcidev->dev, "Link state changed from %s to %s\n",
312                                  (dd->ipath_flags & IPATH_LINKARMED) ? "ARM" : "ACTIVE",
313                                  ib_linkstate(lstate));
314                 /*
315                  * Flush all queued sends when link went to DOWN or INIT,
316                  * to be sure that they don't block SMA and other MAD packets
317                  */
318                 ipath_cancel_sends(dd, 1);
319         }
320         else if (lstate == IPATH_IBSTATE_INIT || lstate == IPATH_IBSTATE_ARM ||
321             lstate == IPATH_IBSTATE_ACTIVE) {
322                 /*
323                  * only print at SMA if there is a change, debug if not
324                  * (sometimes we want to know that, usually not).
325                  */
326                 if (lstate == ((unsigned) dd->ipath_lastibcstat
327                                & IPATH_IBSTATE_MASK)) {
328                         ipath_dbg("Status change intr but no change (%s)\n",
329                                   ib_linkstate(lstate));
330                 }
331                 else
332                         ipath_cdbg(VERBOSE, "Unit %u link state %s, last "
333                                    "was %s\n", dd->ipath_unit,
334                                    ib_linkstate(lstate),
335                                    ib_linkstate((unsigned)
336                                                 dd->ipath_lastibcstat
337                                                 & IPATH_IBSTATE_MASK));
338         }
339         else {
340                 lstate = dd->ipath_lastibcstat & IPATH_IBSTATE_MASK;
341                 if (lstate == IPATH_IBSTATE_INIT ||
342                     lstate == IPATH_IBSTATE_ARM ||
343                     lstate == IPATH_IBSTATE_ACTIVE)
344                         ipath_cdbg(VERBOSE, "Unit %u link state down"
345                                    " (state 0x%x), from %s\n",
346                                    dd->ipath_unit,
347                                    (u32)val & IPATH_IBSTATE_MASK,
348                                    ib_linkstate(lstate));
349                 else
350                         ipath_cdbg(VERBOSE, "Unit %u link state changed "
351                                    "to 0x%x from down (%x)\n",
352                                    dd->ipath_unit, (u32) val, lstate);
353         }
354         ltstate = (val >> INFINIPATH_IBCS_LINKTRAININGSTATE_SHIFT) &
355                 INFINIPATH_IBCS_LINKTRAININGSTATE_MASK;
356         lstate = (val >> INFINIPATH_IBCS_LINKSTATE_SHIFT) &
357                 INFINIPATH_IBCS_LINKSTATE_MASK;
358
359         if (ltstate == INFINIPATH_IBCS_LT_STATE_POLLACTIVE ||
360             ltstate == INFINIPATH_IBCS_LT_STATE_POLLQUIET) {
361                 u32 last_ltstate;
362
363                 /*
364                  * Ignore cycling back and forth from Polling.Active
365                  * to Polling.Quiet while waiting for the other end of
366                  * the link to come up. We will cycle back and forth
367                  * between them if no cable is plugged in,
368                  * the other device is powered off or disabled, etc.
369                  */
370                 last_ltstate = (dd->ipath_lastibcstat >>
371                                 INFINIPATH_IBCS_LINKTRAININGSTATE_SHIFT)
372                         & INFINIPATH_IBCS_LINKTRAININGSTATE_MASK;
373                 if (last_ltstate == INFINIPATH_IBCS_LT_STATE_POLLACTIVE
374                     || last_ltstate ==
375                     INFINIPATH_IBCS_LT_STATE_POLLQUIET) {
376                         if (dd->ipath_ibpollcnt > 40) {
377                                 dd->ipath_flags |= IPATH_NOCABLE;
378                                 *dd->ipath_statusp |=
379                                         IPATH_STATUS_IB_NOCABLE;
380                         } else
381                                 dd->ipath_ibpollcnt++;
382                         goto skip_ibchange;
383                 }
384         }
385         dd->ipath_ibpollcnt = 0;        /* some state other than 2 or 3 */
386         ipath_stats.sps_iblink++;
387         if (ltstate != INFINIPATH_IBCS_LT_STATE_LINKUP) {
388                 if (dd->ipath_flags & IPATH_LINKACTIVE)
389                         signal_ib_event(dd, IB_EVENT_PORT_ERR);
390                 dd->ipath_flags |= IPATH_LINKDOWN;
391                 dd->ipath_flags &= ~(IPATH_LINKUNK | IPATH_LINKINIT
392                                      | IPATH_LINKACTIVE |
393                                      IPATH_LINKARMED);
394                 *dd->ipath_statusp &= ~IPATH_STATUS_IB_READY;
395                 dd->ipath_lli_counter = 0;
396                 if (!noprint) {
397                         if (((dd->ipath_lastibcstat >>
398                               INFINIPATH_IBCS_LINKSTATE_SHIFT) &
399                              INFINIPATH_IBCS_LINKSTATE_MASK)
400                             == INFINIPATH_IBCS_L_STATE_ACTIVE)
401                                 /* if from up to down be more vocal */
402                                 ipath_cdbg(VERBOSE,
403                                            "Unit %u link now down (%s)\n",
404                                            dd->ipath_unit,
405                                            ipath_ibcstatus_str[ltstate]);
406                         else
407                                 ipath_cdbg(VERBOSE, "Unit %u link is "
408                                            "down (%s)\n", dd->ipath_unit,
409                                            ipath_ibcstatus_str[ltstate]);
410                 }
411
412                 dd->ipath_f_setextled(dd, lstate, ltstate);
413         } else if ((val & IPATH_IBSTATE_MASK) == IPATH_IBSTATE_ACTIVE) {
414                 dd->ipath_flags |= IPATH_LINKACTIVE;
415                 dd->ipath_flags &=
416                         ~(IPATH_LINKUNK | IPATH_LINKINIT | IPATH_LINKDOWN |
417                           IPATH_LINKARMED | IPATH_NOCABLE);
418                 *dd->ipath_statusp &= ~IPATH_STATUS_IB_NOCABLE;
419                 *dd->ipath_statusp |=
420                         IPATH_STATUS_IB_READY | IPATH_STATUS_IB_CONF;
421                 dd->ipath_f_setextled(dd, lstate, ltstate);
422                 signal_ib_event(dd, IB_EVENT_PORT_ACTIVE);
423         } else if ((val & IPATH_IBSTATE_MASK) == IPATH_IBSTATE_INIT) {
424                 if (dd->ipath_flags & IPATH_LINKACTIVE)
425                         signal_ib_event(dd, IB_EVENT_PORT_ERR);
426                 /*
427                  * set INIT and DOWN.  Down is checked by most of the other
428                  * code, but INIT is useful to know in a few places.
429                  */
430                 dd->ipath_flags |= IPATH_LINKINIT | IPATH_LINKDOWN;
431                 dd->ipath_flags &=
432                         ~(IPATH_LINKUNK | IPATH_LINKACTIVE | IPATH_LINKARMED
433                           | IPATH_NOCABLE);
434                 *dd->ipath_statusp &= ~(IPATH_STATUS_IB_NOCABLE
435                                         | IPATH_STATUS_IB_READY);
436                 dd->ipath_f_setextled(dd, lstate, ltstate);
437         } else if ((val & IPATH_IBSTATE_MASK) == IPATH_IBSTATE_ARM) {
438                 if (dd->ipath_flags & IPATH_LINKACTIVE)
439                         signal_ib_event(dd, IB_EVENT_PORT_ERR);
440                 dd->ipath_flags |= IPATH_LINKARMED;
441                 dd->ipath_flags &=
442                         ~(IPATH_LINKUNK | IPATH_LINKDOWN | IPATH_LINKINIT |
443                           IPATH_LINKACTIVE | IPATH_NOCABLE);
444                 *dd->ipath_statusp &= ~(IPATH_STATUS_IB_NOCABLE
445                                         | IPATH_STATUS_IB_READY);
446                 dd->ipath_f_setextled(dd, lstate, ltstate);
447         } else {
448                 if (!noprint)
449                         ipath_dbg("IBstatuschange unit %u: %s (%x)\n",
450                                   dd->ipath_unit,
451                                   ipath_ibcstatus_str[ltstate], ltstate);
452         }
453 skip_ibchange:
454         dd->ipath_lastibcstat = val;
455 }
456
457 static void handle_supp_msgs(struct ipath_devdata *dd,
458                              unsigned supp_msgs, char *msg, int msgsz)
459 {
460         /*
461          * Print the message unless it's ibc status change only, which
462          * happens so often we never want to count it.
463          */
464         if (dd->ipath_lasterror & ~INFINIPATH_E_IBSTATUSCHANGED) {
465                 int iserr;
466                 iserr = ipath_decode_err(msg, msgsz,
467                                          dd->ipath_lasterror &
468                                          ~INFINIPATH_E_IBSTATUSCHANGED);
469                 if (dd->ipath_lasterror &
470                         ~(INFINIPATH_E_RRCVEGRFULL |
471                         INFINIPATH_E_RRCVHDRFULL | INFINIPATH_E_PKTERRS))
472                         ipath_dev_err(dd, "Suppressed %u messages for "
473                                       "fast-repeating errors (%s) (%llx)\n",
474                                       supp_msgs, msg,
475                                       (unsigned long long)
476                                       dd->ipath_lasterror);
477                 else {
478                         /*
479                          * rcvegrfull and rcvhdrqfull are "normal", for some
480                          * types of processes (mostly benchmarks) that send
481                          * huge numbers of messages, while not processing
482                          * them. So only complain about these at debug
483                          * level.
484                          */
485                         if (iserr)
486                                 ipath_dbg("Suppressed %u messages for %s\n",
487                                           supp_msgs, msg);
488                         else
489                                 ipath_cdbg(ERRPKT,
490                                         "Suppressed %u messages for %s\n",
491                                           supp_msgs, msg);
492                 }
493         }
494 }
495
496 static unsigned handle_frequent_errors(struct ipath_devdata *dd,
497                                        ipath_err_t errs, char *msg,
498                                        int msgsz, int *noprint)
499 {
500         unsigned long nc;
501         static unsigned long nextmsg_time;
502         static unsigned nmsgs, supp_msgs;
503
504         /*
505          * Throttle back "fast" messages to no more than 10 per 5 seconds.
506          * This isn't perfect, but it's a reasonable heuristic. If we get
507          * more than 10, give a 6x longer delay.
508          */
509         nc = jiffies;
510         if (nmsgs > 10) {
511                 if (time_before(nc, nextmsg_time)) {
512                         *noprint = 1;
513                         if (!supp_msgs++)
514                                 nextmsg_time = nc + HZ * 3;
515                 }
516                 else if (supp_msgs) {
517                         handle_supp_msgs(dd, supp_msgs, msg, msgsz);
518                         supp_msgs = 0;
519                         nmsgs = 0;
520                 }
521         }
522         else if (!nmsgs++ || time_after(nc, nextmsg_time))
523                 nextmsg_time = nc + HZ / 2;
524
525         return supp_msgs;
526 }
527
528 static int handle_errors(struct ipath_devdata *dd, ipath_err_t errs)
529 {
530         char msg[128];
531         u64 ignore_this_time = 0;
532         int i, iserr = 0;
533         int chkerrpkts = 0, noprint = 0;
534         unsigned supp_msgs;
535         int log_idx;
536
537         supp_msgs = handle_frequent_errors(dd, errs, msg, sizeof msg, &noprint);
538
539         /* don't report errors that are masked */
540         errs &= ~dd->ipath_maskederrs;
541
542         /* do these first, they are most important */
543         if (errs & INFINIPATH_E_HARDWARE) {
544                 /* reuse same msg buf */
545                 dd->ipath_f_handle_hwerrors(dd, msg, sizeof msg);
546         } else {
547                 u64 mask;
548                 for (log_idx = 0; log_idx < IPATH_EEP_LOG_CNT; ++log_idx) {
549                         mask = dd->ipath_eep_st_masks[log_idx].errs_to_log;
550                         if (errs & mask)
551                                 ipath_inc_eeprom_err(dd, log_idx, 1);
552                 }
553         }
554
555         if (!noprint && (errs & ~dd->ipath_e_bitsextant))
556                 ipath_dev_err(dd, "error interrupt with unknown errors "
557                               "%llx set\n", (unsigned long long)
558                               (errs & ~dd->ipath_e_bitsextant));
559
560         if (errs & E_SUM_ERRS)
561                 ignore_this_time = handle_e_sum_errs(dd, errs);
562         else if ((errs & E_SUM_LINK_PKTERRS) &&
563             !(dd->ipath_flags & IPATH_LINKACTIVE)) {
564                 /*
565                  * This can happen when SMA is trying to bring the link
566                  * up, but the IB link changes state at the "wrong" time.
567                  * The IB logic then complains that the packet isn't
568                  * valid.  We don't want to confuse people, so we just
569                  * don't print them, except at debug
570                  */
571                 ipath_dbg("Ignoring packet errors %llx, because link not "
572                           "ACTIVE\n", (unsigned long long) errs);
573                 ignore_this_time = errs & E_SUM_LINK_PKTERRS;
574         }
575
576         if (supp_msgs == 250000) {
577                 int s_iserr;
578                 /*
579                  * It's not entirely reasonable assuming that the errors set
580                  * in the last clear period are all responsible for the
581                  * problem, but the alternative is to assume it's the only
582                  * ones on this particular interrupt, which also isn't great
583                  */
584                 dd->ipath_maskederrs |= dd->ipath_lasterror | errs;
585                 dd->ipath_errormask &= ~dd->ipath_maskederrs;
586                 ipath_write_kreg(dd, dd->ipath_kregs->kr_errormask,
587                         dd->ipath_errormask);
588                 s_iserr = ipath_decode_err(msg, sizeof msg,
589                         dd->ipath_maskederrs);
590
591                 if (dd->ipath_maskederrs &
592                         ~(INFINIPATH_E_RRCVEGRFULL |
593                         INFINIPATH_E_RRCVHDRFULL | INFINIPATH_E_PKTERRS))
594                         ipath_dev_err(dd, "Temporarily disabling "
595                             "error(s) %llx reporting; too frequent (%s)\n",
596                                 (unsigned long long)dd->ipath_maskederrs,
597                                 msg);
598                 else {
599                         /*
600                          * rcvegrfull and rcvhdrqfull are "normal",
601                          * for some types of processes (mostly benchmarks)
602                          * that send huge numbers of messages, while not
603                          * processing them.  So only complain about
604                          * these at debug level.
605                          */
606                         if (s_iserr)
607                                 ipath_dbg("Temporarily disabling reporting "
608                                     "too frequent queue full errors (%s)\n",
609                                     msg);
610                         else
611                                 ipath_cdbg(ERRPKT,
612                                     "Temporarily disabling reporting too"
613                                     " frequent packet errors (%s)\n",
614                                     msg);
615                 }
616
617                 /*
618                  * Re-enable the masked errors after around 3 minutes.  in
619                  * ipath_get_faststats().  If we have a series of fast
620                  * repeating but different errors, the interval will keep
621                  * stretching out, but that's OK, as that's pretty
622                  * catastrophic.
623                  */
624                 dd->ipath_unmasktime = jiffies + HZ * 180;
625         }
626
627         ipath_write_kreg(dd, dd->ipath_kregs->kr_errorclear, errs);
628         if (ignore_this_time)
629                 errs &= ~ignore_this_time;
630         if (errs & ~dd->ipath_lasterror) {
631                 errs &= ~dd->ipath_lasterror;
632                 /* never suppress duplicate hwerrors or ibstatuschange */
633                 dd->ipath_lasterror |= errs &
634                         ~(INFINIPATH_E_HARDWARE |
635                           INFINIPATH_E_IBSTATUSCHANGED);
636         }
637
638         /* likely due to cancel, so suppress */
639         if ((errs & (INFINIPATH_E_SPKTLEN | INFINIPATH_E_SPIOARMLAUNCH)) &&
640                 dd->ipath_lastcancel > jiffies) {
641                 ipath_dbg("Suppressed armlaunch/spktlen after error send cancel\n");
642                 errs &= ~(INFINIPATH_E_SPIOARMLAUNCH | INFINIPATH_E_SPKTLEN);
643         }
644
645         if (!errs)
646                 return 0;
647
648         if (!noprint)
649                 /*
650                  * the ones we mask off are handled specially below or above
651                  */
652                 ipath_decode_err(msg, sizeof msg,
653                                  errs & ~(INFINIPATH_E_IBSTATUSCHANGED |
654                                           INFINIPATH_E_RRCVEGRFULL |
655                                           INFINIPATH_E_RRCVHDRFULL |
656                                           INFINIPATH_E_HARDWARE));
657         else
658                 /* so we don't need if (!noprint) at strlcat's below */
659                 *msg = 0;
660
661         if (errs & E_SUM_PKTERRS) {
662                 ipath_stats.sps_pkterrs++;
663                 chkerrpkts = 1;
664         }
665         if (errs & E_SUM_ERRS)
666                 ipath_stats.sps_errs++;
667
668         if (errs & (INFINIPATH_E_RICRC | INFINIPATH_E_RVCRC)) {
669                 ipath_stats.sps_crcerrs++;
670                 chkerrpkts = 1;
671         }
672         iserr = errs & ~(E_SUM_PKTERRS | INFINIPATH_E_PKTERRS);
673
674
675         /*
676          * We don't want to print these two as they happen, or we can make
677          * the situation even worse, because it takes so long to print
678          * messages to serial consoles.  Kernel ports get printed from
679          * fast_stats, no more than every 5 seconds, user ports get printed
680          * on close
681          */
682         if (errs & INFINIPATH_E_RRCVHDRFULL) {
683                 u32 hd, tl;
684                 ipath_stats.sps_hdrqfull++;
685                 for (i = 0; i < dd->ipath_cfgports; i++) {
686                         struct ipath_portdata *pd = dd->ipath_pd[i];
687                         if (i == 0) {
688                                 hd = pd->port_head;
689                                 tl = (u32) le64_to_cpu(
690                                         *dd->ipath_hdrqtailptr);
691                         } else if (pd && pd->port_cnt &&
692                                    pd->port_rcvhdrtail_kvaddr) {
693                                 /*
694                                  * don't report same point multiple times,
695                                  * except kernel
696                                  */
697                                 tl = *(u64 *) pd->port_rcvhdrtail_kvaddr;
698                                 if (tl == pd->port_lastrcvhdrqtail)
699                                         continue;
700                                 hd = ipath_read_ureg32(dd, ur_rcvhdrhead,
701                                                        i);
702                         } else
703                                 continue;
704                         if (hd == (tl + 1) ||
705                             (!hd && tl == dd->ipath_hdrqlast)) {
706                                 if (i == 0)
707                                         chkerrpkts = 1;
708                                 pd->port_lastrcvhdrqtail = tl;
709                                 pd->port_hdrqfull++;
710                                 /* flush hdrqfull so that poll() sees it */
711                                 wmb();
712                                 wake_up_interruptible(&pd->port_wait);
713                         }
714                 }
715         }
716         if (errs & INFINIPATH_E_RRCVEGRFULL) {
717                 struct ipath_portdata *pd = dd->ipath_pd[0];
718
719                 /*
720                  * since this is of less importance and not likely to
721                  * happen without also getting hdrfull, only count
722                  * occurrences; don't check each port (or even the kernel
723                  * vs user)
724                  */
725                 ipath_stats.sps_etidfull++;
726                 if (pd->port_head !=
727                     (u32) le64_to_cpu(*dd->ipath_hdrqtailptr))
728                         chkerrpkts = 1;
729         }
730
731         /*
732          * do this before IBSTATUSCHANGED, in case both bits set in a single
733          * interrupt; we want the STATUSCHANGE to "win", so we do our
734          * internal copy of state machine correctly
735          */
736         if (errs & INFINIPATH_E_RIBLOSTLINK) {
737                 /*
738                  * force through block below
739                  */
740                 errs |= INFINIPATH_E_IBSTATUSCHANGED;
741                 ipath_stats.sps_iblink++;
742                 dd->ipath_flags |= IPATH_LINKDOWN;
743                 dd->ipath_flags &= ~(IPATH_LINKUNK | IPATH_LINKINIT
744                                      | IPATH_LINKARMED | IPATH_LINKACTIVE);
745                 *dd->ipath_statusp &= ~IPATH_STATUS_IB_READY;
746                 if (!noprint) {
747                         u64 st = ipath_read_kreg64(
748                                 dd, dd->ipath_kregs->kr_ibcstatus);
749
750                         ipath_dbg("Lost link, link now down (%s)\n",
751                                   ipath_ibcstatus_str[st & 0xf]);
752                 }
753         }
754         if (errs & INFINIPATH_E_IBSTATUSCHANGED)
755                 handle_e_ibstatuschanged(dd, errs, noprint);
756
757         if (errs & INFINIPATH_E_RESET) {
758                 if (!noprint)
759                         ipath_dev_err(dd, "Got reset, requires re-init "
760                                       "(unload and reload driver)\n");
761                 dd->ipath_flags &= ~IPATH_INITTED;      /* needs re-init */
762                 /* mark as having had error */
763                 *dd->ipath_statusp |= IPATH_STATUS_HWERROR;
764                 *dd->ipath_statusp &= ~IPATH_STATUS_IB_CONF;
765         }
766
767         if (!noprint && *msg) {
768                 if (iserr)
769                         ipath_dev_err(dd, "%s error\n", msg);
770                 else
771                         dev_info(&dd->pcidev->dev, "%s packet problems\n",
772                                 msg);
773         }
774         if (dd->ipath_state_wanted & dd->ipath_flags) {
775                 ipath_cdbg(VERBOSE, "driver wanted state %x, iflags now %x, "
776                            "waking\n", dd->ipath_state_wanted,
777                            dd->ipath_flags);
778                 wake_up_interruptible(&ipath_state_wait);
779         }
780
781         return chkerrpkts;
782 }
783
784
785 /*
786  * try to cleanup as much as possible for anything that might have gone
787  * wrong while in freeze mode, such as pio buffers being written by user
788  * processes (causing armlaunch), send errors due to going into freeze mode,
789  * etc., and try to avoid causing extra interrupts while doing so.
790  * Forcibly update the in-memory pioavail register copies after cleanup
791  * because the chip won't do it for anything changing while in freeze mode
792  * (we don't want to wait for the next pio buffer state change).
793  * Make sure that we don't lose any important interrupts by using the chip
794  * feature that says that writing 0 to a bit in *clear that is set in
795  * *status will cause an interrupt to be generated again (if allowed by
796  * the *mask value).
797  */
798 void ipath_clear_freeze(struct ipath_devdata *dd)
799 {
800         int i, im;
801         __le64 val;
802         unsigned long flags;
803
804         /* disable error interrupts, to avoid confusion */
805         ipath_write_kreg(dd, dd->ipath_kregs->kr_errormask, 0ULL);
806
807         /* also disable interrupts; errormask is sometimes overwriten */
808         ipath_write_kreg(dd, dd->ipath_kregs->kr_intmask, 0ULL);
809
810         /*
811          * clear all sends, because they have may been
812          * completed by usercode while in freeze mode, and
813          * therefore would not be sent, and eventually
814          * might cause the process to run out of bufs
815          */
816         ipath_cancel_sends(dd, 0);
817         ipath_write_kreg(dd, dd->ipath_kregs->kr_control,
818                          dd->ipath_control);
819
820         /* ensure pio avail updates continue */
821         spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
822         ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
823                  dd->ipath_sendctrl & ~INFINIPATH_S_PIOBUFAVAILUPD);
824         ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
825         ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
826                          dd->ipath_sendctrl);
827         ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
828         spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
829
830         /*
831          * We just enabled pioavailupdate, so dma copy is almost certainly
832          * not yet right, so read the registers directly.  Similar to init
833          */
834         for (i = 0; i < dd->ipath_pioavregs; i++) {
835                 /* deal with 6110 chip bug */
836                 im = i > 3 ? i ^ 1 : i;
837                 val = ipath_read_kreg64(dd, (0x1000 / sizeof(u64)) + im);
838                 dd->ipath_pioavailregs_dma[i] = dd->ipath_pioavailshadow[i]
839                         = le64_to_cpu(val);
840         }
841
842         /*
843          * force new interrupt if any hwerr, error or interrupt bits are
844          * still set, and clear "safe" send packet errors related to freeze
845          * and cancelling sends.  Re-enable error interrupts before possible
846          * force of re-interrupt on pending interrupts.
847          */
848         ipath_write_kreg(dd, dd->ipath_kregs->kr_hwerrclear, 0ULL);
849         ipath_write_kreg(dd, dd->ipath_kregs->kr_errorclear,
850                 E_SPKT_ERRS_IGNORE);
851         ipath_write_kreg(dd, dd->ipath_kregs->kr_errormask,
852                 dd->ipath_errormask);
853         ipath_write_kreg(dd, dd->ipath_kregs->kr_intmask, -1LL);
854         ipath_write_kreg(dd, dd->ipath_kregs->kr_intclear, 0ULL);
855 }
856
857
858 /* this is separate to allow for better optimization of ipath_intr() */
859
860 static noinline void ipath_bad_intr(struct ipath_devdata *dd, u32 *unexpectp)
861 {
862         /*
863          * sometimes happen during driver init and unload, don't want
864          * to process any interrupts at that point
865          */
866
867         /* this is just a bandaid, not a fix, if something goes badly
868          * wrong */
869         if (++*unexpectp > 100) {
870                 if (++*unexpectp > 105) {
871                         /*
872                          * ok, we must be taking somebody else's interrupts,
873                          * due to a messed up mptable and/or PIRQ table, so
874                          * unregister the interrupt.  We've seen this during
875                          * linuxbios development work, and it may happen in
876                          * the future again.
877                          */
878                         if (dd->pcidev && dd->ipath_irq) {
879                                 ipath_dev_err(dd, "Now %u unexpected "
880                                               "interrupts, unregistering "
881                                               "interrupt handler\n",
882                                               *unexpectp);
883                                 ipath_dbg("free_irq of irq %d\n",
884                                           dd->ipath_irq);
885                                 dd->ipath_f_free_irq(dd);
886                         }
887                 }
888                 if (ipath_read_ireg(dd, dd->ipath_kregs->kr_intmask)) {
889                         ipath_dev_err(dd, "%u unexpected interrupts, "
890                                       "disabling interrupts completely\n",
891                                       *unexpectp);
892                         /*
893                          * disable all interrupts, something is very wrong
894                          */
895                         ipath_write_kreg(dd, dd->ipath_kregs->kr_intmask,
896                                          0ULL);
897                 }
898         } else if (*unexpectp > 1)
899                 ipath_dbg("Interrupt when not ready, should not happen, "
900                           "ignoring\n");
901 }
902
903 static noinline void ipath_bad_regread(struct ipath_devdata *dd)
904 {
905         static int allbits;
906
907         /* separate routine, for better optimization of ipath_intr() */
908
909         /*
910          * We print the message and disable interrupts, in hope of
911          * having a better chance of debugging the problem.
912          */
913         ipath_dev_err(dd,
914                       "Read of interrupt status failed (all bits set)\n");
915         if (allbits++) {
916                 /* disable all interrupts, something is very wrong */
917                 ipath_write_kreg(dd, dd->ipath_kregs->kr_intmask, 0ULL);
918                 if (allbits == 2) {
919                         ipath_dev_err(dd, "Still bad interrupt status, "
920                                       "unregistering interrupt\n");
921                         dd->ipath_f_free_irq(dd);
922                 } else if (allbits > 2) {
923                         if ((allbits % 10000) == 0)
924                                 printk(".");
925                 } else
926                         ipath_dev_err(dd, "Disabling interrupts, "
927                                       "multiple errors\n");
928         }
929 }
930
931 static void handle_layer_pioavail(struct ipath_devdata *dd)
932 {
933         unsigned long flags;
934         int ret;
935
936         ret = ipath_ib_piobufavail(dd->verbs_dev);
937         if (ret > 0)
938                 goto set;
939
940         return;
941 set:
942         spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
943         dd->ipath_sendctrl |= INFINIPATH_S_PIOINTBUFAVAIL;
944         ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
945                          dd->ipath_sendctrl);
946         ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
947         spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
948 }
949
950 /*
951  * Handle receive interrupts for user ports; this means a user
952  * process was waiting for a packet to arrive, and didn't want
953  * to poll
954  */
955 static void handle_urcv(struct ipath_devdata *dd, u32 istat)
956 {
957         u64 portr;
958         int i;
959         int rcvdint = 0;
960
961         /*
962          * test_and_clear_bit(IPATH_PORT_WAITING_RCV) and
963          * test_and_clear_bit(IPATH_PORT_WAITING_URG) below
964          * would both like timely updates of the bits so that
965          * we don't pass them by unnecessarily.  the rmb()
966          * here ensures that we see them promptly -- the
967          * corresponding wmb()'s are in ipath_poll_urgent()
968          * and ipath_poll_next()...
969          */
970         rmb();
971         portr = ((istat >> INFINIPATH_I_RCVAVAIL_SHIFT) &
972                  dd->ipath_i_rcvavail_mask)
973                 | ((istat >> INFINIPATH_I_RCVURG_SHIFT) &
974                    dd->ipath_i_rcvurg_mask);
975         for (i = 1; i < dd->ipath_cfgports; i++) {
976                 struct ipath_portdata *pd = dd->ipath_pd[i];
977                 if (portr & (1 << i) && pd && pd->port_cnt) {
978                         if (test_and_clear_bit(IPATH_PORT_WAITING_RCV,
979                                                &pd->port_flag)) {
980                                 clear_bit(i + dd->ipath_r_intravail_shift,
981                                           &dd->ipath_rcvctrl);
982                                 wake_up_interruptible(&pd->port_wait);
983                                 rcvdint = 1;
984                         } else if (test_and_clear_bit(IPATH_PORT_WAITING_URG,
985                                                       &pd->port_flag)) {
986                                 pd->port_urgent++;
987                                 wake_up_interruptible(&pd->port_wait);
988                         }
989                 }
990         }
991         if (rcvdint) {
992                 /* only want to take one interrupt, so turn off the rcv
993                  * interrupt for all the ports that we did the wakeup on
994                  * (but never for kernel port)
995                  */
996                 ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
997                                  dd->ipath_rcvctrl);
998         }
999 }
1000
1001 irqreturn_t ipath_intr(int irq, void *data)
1002 {
1003         struct ipath_devdata *dd = data;
1004         u32 istat, chk0rcv = 0;
1005         ipath_err_t estat = 0;
1006         irqreturn_t ret;
1007         static unsigned unexpected = 0;
1008         static const u32 port0rbits = (1U<<INFINIPATH_I_RCVAVAIL_SHIFT) |
1009                  (1U<<INFINIPATH_I_RCVURG_SHIFT);
1010
1011         ipath_stats.sps_ints++;
1012
1013         if (dd->ipath_int_counter != (u32) -1)
1014                 dd->ipath_int_counter++;
1015
1016         if (!(dd->ipath_flags & IPATH_PRESENT)) {
1017                 /*
1018                  * This return value is not great, but we do not want the
1019                  * interrupt core code to remove our interrupt handler
1020                  * because we don't appear to be handling an interrupt
1021                  * during a chip reset.
1022                  */
1023                 return IRQ_HANDLED;
1024         }
1025
1026         /*
1027          * this needs to be flags&initted, not statusp, so we keep
1028          * taking interrupts even after link goes down, etc.
1029          * Also, we *must* clear the interrupt at some point, or we won't
1030          * take it again, which can be real bad for errors, etc...
1031          */
1032
1033         if (!(dd->ipath_flags & IPATH_INITTED)) {
1034                 ipath_bad_intr(dd, &unexpected);
1035                 ret = IRQ_NONE;
1036                 goto bail;
1037         }
1038
1039         istat = ipath_read_ireg(dd, dd->ipath_kregs->kr_intstatus);
1040
1041         if (unlikely(!istat)) {
1042                 ipath_stats.sps_nullintr++;
1043                 ret = IRQ_NONE; /* not our interrupt, or already handled */
1044                 goto bail;
1045         }
1046         if (unlikely(istat == -1)) {
1047                 ipath_bad_regread(dd);
1048                 /* don't know if it was our interrupt or not */
1049                 ret = IRQ_NONE;
1050                 goto bail;
1051         }
1052
1053         if (unexpected)
1054                 unexpected = 0;
1055
1056         if (unlikely(istat & ~dd->ipath_i_bitsextant))
1057                 ipath_dev_err(dd,
1058                               "interrupt with unknown interrupts %x set\n",
1059                               istat & (u32) ~ dd->ipath_i_bitsextant);
1060         else
1061                 ipath_cdbg(VERBOSE, "intr stat=0x%x\n", istat);
1062
1063         if (unlikely(istat & INFINIPATH_I_ERROR)) {
1064                 ipath_stats.sps_errints++;
1065                 estat = ipath_read_kreg64(dd,
1066                                           dd->ipath_kregs->kr_errorstatus);
1067                 if (!estat)
1068                         dev_info(&dd->pcidev->dev, "error interrupt (%x), "
1069                                  "but no error bits set!\n", istat);
1070                 else if (estat == -1LL)
1071                         /*
1072                          * should we try clearing all, or hope next read
1073                          * works?
1074                          */
1075                         ipath_dev_err(dd, "Read of error status failed "
1076                                       "(all bits set); ignoring\n");
1077                 else
1078                         if (handle_errors(dd, estat))
1079                                 /* force calling ipath_kreceive() */
1080                                 chk0rcv = 1;
1081         }
1082
1083         if (istat & INFINIPATH_I_GPIO) {
1084                 /*
1085                  * GPIO interrupts fall in two broad classes:
1086                  * GPIO_2 indicates (on some HT4xx boards) that a packet
1087                  *        has arrived for Port 0. Checking for this
1088                  *        is controlled by flag IPATH_GPIO_INTR.
1089                  * GPIO_3..5 on IBA6120 Rev2 and IBA6110 Rev4 chips indicate
1090                  *        errors that we need to count. Checking for this
1091                  *        is controlled by flag IPATH_GPIO_ERRINTRS.
1092                  */
1093                 u32 gpiostatus;
1094                 u32 to_clear = 0;
1095
1096                 gpiostatus = ipath_read_kreg32(
1097                         dd, dd->ipath_kregs->kr_gpio_status);
1098                 /* First the error-counter case.
1099                  */
1100                 if ((gpiostatus & IPATH_GPIO_ERRINTR_MASK) &&
1101                     (dd->ipath_flags & IPATH_GPIO_ERRINTRS)) {
1102                         /* want to clear the bits we see asserted. */
1103                         to_clear |= (gpiostatus & IPATH_GPIO_ERRINTR_MASK);
1104
1105                         /*
1106                          * Count appropriately, clear bits out of our copy,
1107                          * as they have been "handled".
1108                          */
1109                         if (gpiostatus & (1 << IPATH_GPIO_RXUVL_BIT)) {
1110                                 ipath_dbg("FlowCtl on UnsupVL\n");
1111                                 dd->ipath_rxfc_unsupvl_errs++;
1112                         }
1113                         if (gpiostatus & (1 << IPATH_GPIO_OVRUN_BIT)) {
1114                                 ipath_dbg("Overrun Threshold exceeded\n");
1115                                 dd->ipath_overrun_thresh_errs++;
1116                         }
1117                         if (gpiostatus & (1 << IPATH_GPIO_LLI_BIT)) {
1118                                 ipath_dbg("Local Link Integrity error\n");
1119                                 dd->ipath_lli_errs++;
1120                         }
1121                         gpiostatus &= ~IPATH_GPIO_ERRINTR_MASK;
1122                 }
1123                 /* Now the Port0 Receive case */
1124                 if ((gpiostatus & (1 << IPATH_GPIO_PORT0_BIT)) &&
1125                     (dd->ipath_flags & IPATH_GPIO_INTR)) {
1126                         /*
1127                          * GPIO status bit 2 is set, and we expected it.
1128                          * clear it and indicate in p0bits.
1129                          * This probably only happens if a Port0 pkt
1130                          * arrives at _just_ the wrong time, and we
1131                          * handle that by seting chk0rcv;
1132                          */
1133                         to_clear |= (1 << IPATH_GPIO_PORT0_BIT);
1134                         gpiostatus &= ~(1 << IPATH_GPIO_PORT0_BIT);
1135                         chk0rcv = 1;
1136                 }
1137                 if (gpiostatus) {
1138                         /*
1139                          * Some unexpected bits remain. If they could have
1140                          * caused the interrupt, complain and clear.
1141                          * To avoid repetition of this condition, also clear
1142                          * the mask. It is almost certainly due to error.
1143                          */
1144                         const u32 mask = (u32) dd->ipath_gpio_mask;
1145
1146                         if (mask & gpiostatus) {
1147                                 ipath_dbg("Unexpected GPIO IRQ bits %x\n",
1148                                   gpiostatus & mask);
1149                                 to_clear |= (gpiostatus & mask);
1150                                 dd->ipath_gpio_mask &= ~(gpiostatus & mask);
1151                                 ipath_write_kreg(dd,
1152                                         dd->ipath_kregs->kr_gpio_mask,
1153                                         dd->ipath_gpio_mask);
1154                         }
1155                 }
1156                 if (to_clear) {
1157                         ipath_write_kreg(dd, dd->ipath_kregs->kr_gpio_clear,
1158                                         (u64) to_clear);
1159                 }
1160         }
1161         chk0rcv |= istat & port0rbits;
1162
1163         /*
1164          * Clear the interrupt bits we found set, unless they are receive
1165          * related, in which case we already cleared them above, and don't
1166          * want to clear them again, because we might lose an interrupt.
1167          * Clear it early, so we "know" know the chip will have seen this by
1168          * the time we process the queue, and will re-interrupt if necessary.
1169          * The processor itself won't take the interrupt again until we return.
1170          */
1171         ipath_write_kreg(dd, dd->ipath_kregs->kr_intclear, istat);
1172
1173         /*
1174          * handle port0 receive  before checking for pio buffers available,
1175          * since receives can overflow; piobuf waiters can afford a few
1176          * extra cycles, since they were waiting anyway, and user's waiting
1177          * for receive are at the bottom.
1178          */
1179         if (chk0rcv) {
1180                 ipath_kreceive(dd->ipath_pd[0]);
1181                 istat &= ~port0rbits;
1182         }
1183
1184         if (istat & ((dd->ipath_i_rcvavail_mask <<
1185                       INFINIPATH_I_RCVAVAIL_SHIFT)
1186                      | (dd->ipath_i_rcvurg_mask <<
1187                         INFINIPATH_I_RCVURG_SHIFT)))
1188                 handle_urcv(dd, istat);
1189
1190         if (istat & INFINIPATH_I_SPIOBUFAVAIL) {
1191                 unsigned long flags;
1192
1193                 spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
1194                 dd->ipath_sendctrl &= ~INFINIPATH_S_PIOINTBUFAVAIL;
1195                 ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
1196                                  dd->ipath_sendctrl);
1197                 ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
1198                 spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
1199
1200                 handle_layer_pioavail(dd);
1201         }
1202
1203         ret = IRQ_HANDLED;
1204
1205 bail:
1206         return ret;
1207 }