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TOMOYO Linux Cross Reference
Linux/arch/x86/platform/uv/tlb_uv.c

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  1 /*
  2  *      SGI UltraViolet TLB flush routines.
  3  *
  4  *      (c) 2008-2012 Cliff Wickman <cpw@sgi.com>, SGI.
  5  *
  6  *      This code is released under the GNU General Public License version 2 or
  7  *      later.
  8  */
  9 #include <linux/seq_file.h>
 10 #include <linux/proc_fs.h>
 11 #include <linux/debugfs.h>
 12 #include <linux/kernel.h>
 13 #include <linux/slab.h>
 14 #include <linux/delay.h>
 15 
 16 #include <asm/mmu_context.h>
 17 #include <asm/uv/uv.h>
 18 #include <asm/uv/uv_mmrs.h>
 19 #include <asm/uv/uv_hub.h>
 20 #include <asm/uv/uv_bau.h>
 21 #include <asm/apic.h>
 22 #include <asm/idle.h>
 23 #include <asm/tsc.h>
 24 #include <asm/irq_vectors.h>
 25 #include <asm/timer.h>
 26 
 27 /* timeouts in nanoseconds (indexed by UVH_AGING_PRESCALE_SEL urgency7 30:28) */
 28 static int timeout_base_ns[] = {
 29                 20,
 30                 160,
 31                 1280,
 32                 10240,
 33                 81920,
 34                 655360,
 35                 5242880,
 36                 167772160
 37 };
 38 
 39 static int timeout_us;
 40 static int nobau;
 41 static int nobau_perm;
 42 static cycles_t congested_cycles;
 43 
 44 /* tunables: */
 45 static int max_concurr          = MAX_BAU_CONCURRENT;
 46 static int max_concurr_const    = MAX_BAU_CONCURRENT;
 47 static int plugged_delay        = PLUGGED_DELAY;
 48 static int plugsb4reset         = PLUGSB4RESET;
 49 static int giveup_limit         = GIVEUP_LIMIT;
 50 static int timeoutsb4reset      = TIMEOUTSB4RESET;
 51 static int ipi_reset_limit      = IPI_RESET_LIMIT;
 52 static int complete_threshold   = COMPLETE_THRESHOLD;
 53 static int congested_respns_us  = CONGESTED_RESPONSE_US;
 54 static int congested_reps       = CONGESTED_REPS;
 55 static int disabled_period      = DISABLED_PERIOD;
 56 
 57 static struct tunables tunables[] = {
 58         {&max_concurr, MAX_BAU_CONCURRENT}, /* must be [0] */
 59         {&plugged_delay, PLUGGED_DELAY},
 60         {&plugsb4reset, PLUGSB4RESET},
 61         {&timeoutsb4reset, TIMEOUTSB4RESET},
 62         {&ipi_reset_limit, IPI_RESET_LIMIT},
 63         {&complete_threshold, COMPLETE_THRESHOLD},
 64         {&congested_respns_us, CONGESTED_RESPONSE_US},
 65         {&congested_reps, CONGESTED_REPS},
 66         {&disabled_period, DISABLED_PERIOD},
 67         {&giveup_limit, GIVEUP_LIMIT}
 68 };
 69 
 70 static struct dentry *tunables_dir;
 71 static struct dentry *tunables_file;
 72 
 73 /* these correspond to the statistics printed by ptc_seq_show() */
 74 static char *stat_description[] = {
 75         "sent:     number of shootdown messages sent",
 76         "stime:    time spent sending messages",
 77         "numuvhubs: number of hubs targeted with shootdown",
 78         "numuvhubs16: number times 16 or more hubs targeted",
 79         "numuvhubs8: number times 8 or more hubs targeted",
 80         "numuvhubs4: number times 4 or more hubs targeted",
 81         "numuvhubs2: number times 2 or more hubs targeted",
 82         "numuvhubs1: number times 1 hub targeted",
 83         "numcpus:  number of cpus targeted with shootdown",
 84         "dto:      number of destination timeouts",
 85         "retries:  destination timeout retries sent",
 86         "rok:   :  destination timeouts successfully retried",
 87         "resetp:   ipi-style resource resets for plugs",
 88         "resett:   ipi-style resource resets for timeouts",
 89         "giveup:   fall-backs to ipi-style shootdowns",
 90         "sto:      number of source timeouts",
 91         "bz:       number of stay-busy's",
 92         "throt:    number times spun in throttle",
 93         "swack:   image of UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE",
 94         "recv:     shootdown messages received",
 95         "rtime:    time spent processing messages",
 96         "all:      shootdown all-tlb messages",
 97         "one:      shootdown one-tlb messages",
 98         "mult:     interrupts that found multiple messages",
 99         "none:     interrupts that found no messages",
100         "retry:    number of retry messages processed",
101         "canc:     number messages canceled by retries",
102         "nocan:    number retries that found nothing to cancel",
103         "reset:    number of ipi-style reset requests processed",
104         "rcan:     number messages canceled by reset requests",
105         "disable:  number times use of the BAU was disabled",
106         "enable:   number times use of the BAU was re-enabled"
107 };
108 
109 static int __init
110 setup_nobau(char *arg)
111 {
112         nobau = 1;
113         return 0;
114 }
115 early_param("nobau", setup_nobau);
116 
117 /* base pnode in this partition */
118 static int uv_base_pnode __read_mostly;
119 
120 static DEFINE_PER_CPU(struct ptc_stats, ptcstats);
121 static DEFINE_PER_CPU(struct bau_control, bau_control);
122 static DEFINE_PER_CPU(cpumask_var_t, uv_flush_tlb_mask);
123 
124 static void
125 set_bau_on(void)
126 {
127         int cpu;
128         struct bau_control *bcp;
129 
130         if (nobau_perm) {
131                 pr_info("BAU not initialized; cannot be turned on\n");
132                 return;
133         }
134         nobau = 0;
135         for_each_present_cpu(cpu) {
136                 bcp = &per_cpu(bau_control, cpu);
137                 bcp->nobau = 0;
138         }
139         pr_info("BAU turned on\n");
140         return;
141 }
142 
143 static void
144 set_bau_off(void)
145 {
146         int cpu;
147         struct bau_control *bcp;
148 
149         nobau = 1;
150         for_each_present_cpu(cpu) {
151                 bcp = &per_cpu(bau_control, cpu);
152                 bcp->nobau = 1;
153         }
154         pr_info("BAU turned off\n");
155         return;
156 }
157 
158 /*
159  * Determine the first node on a uvhub. 'Nodes' are used for kernel
160  * memory allocation.
161  */
162 static int __init uvhub_to_first_node(int uvhub)
163 {
164         int node, b;
165 
166         for_each_online_node(node) {
167                 b = uv_node_to_blade_id(node);
168                 if (uvhub == b)
169                         return node;
170         }
171         return -1;
172 }
173 
174 /*
175  * Determine the apicid of the first cpu on a uvhub.
176  */
177 static int __init uvhub_to_first_apicid(int uvhub)
178 {
179         int cpu;
180 
181         for_each_present_cpu(cpu)
182                 if (uvhub == uv_cpu_to_blade_id(cpu))
183                         return per_cpu(x86_cpu_to_apicid, cpu);
184         return -1;
185 }
186 
187 /*
188  * Free a software acknowledge hardware resource by clearing its Pending
189  * bit. This will return a reply to the sender.
190  * If the message has timed out, a reply has already been sent by the
191  * hardware but the resource has not been released. In that case our
192  * clear of the Timeout bit (as well) will free the resource. No reply will
193  * be sent (the hardware will only do one reply per message).
194  */
195 static void reply_to_message(struct msg_desc *mdp, struct bau_control *bcp,
196                                                 int do_acknowledge)
197 {
198         unsigned long dw;
199         struct bau_pq_entry *msg;
200 
201         msg = mdp->msg;
202         if (!msg->canceled && do_acknowledge) {
203                 dw = (msg->swack_vec << UV_SW_ACK_NPENDING) | msg->swack_vec;
204                 write_mmr_sw_ack(dw);
205         }
206         msg->replied_to = 1;
207         msg->swack_vec = 0;
208 }
209 
210 /*
211  * Process the receipt of a RETRY message
212  */
213 static void bau_process_retry_msg(struct msg_desc *mdp,
214                                         struct bau_control *bcp)
215 {
216         int i;
217         int cancel_count = 0;
218         unsigned long msg_res;
219         unsigned long mmr = 0;
220         struct bau_pq_entry *msg = mdp->msg;
221         struct bau_pq_entry *msg2;
222         struct ptc_stats *stat = bcp->statp;
223 
224         stat->d_retries++;
225         /*
226          * cancel any message from msg+1 to the retry itself
227          */
228         for (msg2 = msg+1, i = 0; i < DEST_Q_SIZE; msg2++, i++) {
229                 if (msg2 > mdp->queue_last)
230                         msg2 = mdp->queue_first;
231                 if (msg2 == msg)
232                         break;
233 
234                 /* same conditions for cancellation as do_reset */
235                 if ((msg2->replied_to == 0) && (msg2->canceled == 0) &&
236                     (msg2->swack_vec) && ((msg2->swack_vec &
237                         msg->swack_vec) == 0) &&
238                     (msg2->sending_cpu == msg->sending_cpu) &&
239                     (msg2->msg_type != MSG_NOOP)) {
240                         mmr = read_mmr_sw_ack();
241                         msg_res = msg2->swack_vec;
242                         /*
243                          * This is a message retry; clear the resources held
244                          * by the previous message only if they timed out.
245                          * If it has not timed out we have an unexpected
246                          * situation to report.
247                          */
248                         if (mmr & (msg_res << UV_SW_ACK_NPENDING)) {
249                                 unsigned long mr;
250                                 /*
251                                  * Is the resource timed out?
252                                  * Make everyone ignore the cancelled message.
253                                  */
254                                 msg2->canceled = 1;
255                                 stat->d_canceled++;
256                                 cancel_count++;
257                                 mr = (msg_res << UV_SW_ACK_NPENDING) | msg_res;
258                                 write_mmr_sw_ack(mr);
259                         }
260                 }
261         }
262         if (!cancel_count)
263                 stat->d_nocanceled++;
264 }
265 
266 /*
267  * Do all the things a cpu should do for a TLB shootdown message.
268  * Other cpu's may come here at the same time for this message.
269  */
270 static void bau_process_message(struct msg_desc *mdp, struct bau_control *bcp,
271                                                 int do_acknowledge)
272 {
273         short socket_ack_count = 0;
274         short *sp;
275         struct atomic_short *asp;
276         struct ptc_stats *stat = bcp->statp;
277         struct bau_pq_entry *msg = mdp->msg;
278         struct bau_control *smaster = bcp->socket_master;
279 
280         /*
281          * This must be a normal message, or retry of a normal message
282          */
283         if (msg->address == TLB_FLUSH_ALL) {
284                 local_flush_tlb();
285                 stat->d_alltlb++;
286         } else {
287                 __flush_tlb_one(msg->address);
288                 stat->d_onetlb++;
289         }
290         stat->d_requestee++;
291 
292         /*
293          * One cpu on each uvhub has the additional job on a RETRY
294          * of releasing the resource held by the message that is
295          * being retried.  That message is identified by sending
296          * cpu number.
297          */
298         if (msg->msg_type == MSG_RETRY && bcp == bcp->uvhub_master)
299                 bau_process_retry_msg(mdp, bcp);
300 
301         /*
302          * This is a swack message, so we have to reply to it.
303          * Count each responding cpu on the socket. This avoids
304          * pinging the count's cache line back and forth between
305          * the sockets.
306          */
307         sp = &smaster->socket_acknowledge_count[mdp->msg_slot];
308         asp = (struct atomic_short *)sp;
309         socket_ack_count = atom_asr(1, asp);
310         if (socket_ack_count == bcp->cpus_in_socket) {
311                 int msg_ack_count;
312                 /*
313                  * Both sockets dump their completed count total into
314                  * the message's count.
315                  */
316                 *sp = 0;
317                 asp = (struct atomic_short *)&msg->acknowledge_count;
318                 msg_ack_count = atom_asr(socket_ack_count, asp);
319 
320                 if (msg_ack_count == bcp->cpus_in_uvhub) {
321                         /*
322                          * All cpus in uvhub saw it; reply
323                          * (unless we are in the UV2 workaround)
324                          */
325                         reply_to_message(mdp, bcp, do_acknowledge);
326                 }
327         }
328 
329         return;
330 }
331 
332 /*
333  * Determine the first cpu on a pnode.
334  */
335 static int pnode_to_first_cpu(int pnode, struct bau_control *smaster)
336 {
337         int cpu;
338         struct hub_and_pnode *hpp;
339 
340         for_each_present_cpu(cpu) {
341                 hpp = &smaster->thp[cpu];
342                 if (pnode == hpp->pnode)
343                         return cpu;
344         }
345         return -1;
346 }
347 
348 /*
349  * Last resort when we get a large number of destination timeouts is
350  * to clear resources held by a given cpu.
351  * Do this with IPI so that all messages in the BAU message queue
352  * can be identified by their nonzero swack_vec field.
353  *
354  * This is entered for a single cpu on the uvhub.
355  * The sender want's this uvhub to free a specific message's
356  * swack resources.
357  */
358 static void do_reset(void *ptr)
359 {
360         int i;
361         struct bau_control *bcp = &per_cpu(bau_control, smp_processor_id());
362         struct reset_args *rap = (struct reset_args *)ptr;
363         struct bau_pq_entry *msg;
364         struct ptc_stats *stat = bcp->statp;
365 
366         stat->d_resets++;
367         /*
368          * We're looking for the given sender, and
369          * will free its swack resource.
370          * If all cpu's finally responded after the timeout, its
371          * message 'replied_to' was set.
372          */
373         for (msg = bcp->queue_first, i = 0; i < DEST_Q_SIZE; msg++, i++) {
374                 unsigned long msg_res;
375                 /* do_reset: same conditions for cancellation as
376                    bau_process_retry_msg() */
377                 if ((msg->replied_to == 0) &&
378                     (msg->canceled == 0) &&
379                     (msg->sending_cpu == rap->sender) &&
380                     (msg->swack_vec) &&
381                     (msg->msg_type != MSG_NOOP)) {
382                         unsigned long mmr;
383                         unsigned long mr;
384                         /*
385                          * make everyone else ignore this message
386                          */
387                         msg->canceled = 1;
388                         /*
389                          * only reset the resource if it is still pending
390                          */
391                         mmr = read_mmr_sw_ack();
392                         msg_res = msg->swack_vec;
393                         mr = (msg_res << UV_SW_ACK_NPENDING) | msg_res;
394                         if (mmr & msg_res) {
395                                 stat->d_rcanceled++;
396                                 write_mmr_sw_ack(mr);
397                         }
398                 }
399         }
400         return;
401 }
402 
403 /*
404  * Use IPI to get all target uvhubs to release resources held by
405  * a given sending cpu number.
406  */
407 static void reset_with_ipi(struct pnmask *distribution, struct bau_control *bcp)
408 {
409         int pnode;
410         int apnode;
411         int maskbits;
412         int sender = bcp->cpu;
413         cpumask_t *mask = bcp->uvhub_master->cpumask;
414         struct bau_control *smaster = bcp->socket_master;
415         struct reset_args reset_args;
416 
417         reset_args.sender = sender;
418         cpus_clear(*mask);
419         /* find a single cpu for each uvhub in this distribution mask */
420         maskbits = sizeof(struct pnmask) * BITSPERBYTE;
421         /* each bit is a pnode relative to the partition base pnode */
422         for (pnode = 0; pnode < maskbits; pnode++) {
423                 int cpu;
424                 if (!bau_uvhub_isset(pnode, distribution))
425                         continue;
426                 apnode = pnode + bcp->partition_base_pnode;
427                 cpu = pnode_to_first_cpu(apnode, smaster);
428                 cpu_set(cpu, *mask);
429         }
430 
431         /* IPI all cpus; preemption is already disabled */
432         smp_call_function_many(mask, do_reset, (void *)&reset_args, 1);
433         return;
434 }
435 
436 /*
437  * Not to be confused with cycles_2_ns() from tsc.c; this gives a relative
438  * number, not an absolute. It converts a duration in cycles to a duration in
439  * ns.
440  */
441 static inline unsigned long long cycles_2_ns(unsigned long long cyc)
442 {
443         struct cyc2ns_data *data = cyc2ns_read_begin();
444         unsigned long long ns;
445 
446         ns = mul_u64_u32_shr(cyc, data->cyc2ns_mul, data->cyc2ns_shift);
447 
448         cyc2ns_read_end(data);
449         return ns;
450 }
451 
452 /*
453  * The reverse of the above; converts a duration in ns to a duration in cycles.
454  */ 
455 static inline unsigned long long ns_2_cycles(unsigned long long ns)
456 {
457         struct cyc2ns_data *data = cyc2ns_read_begin();
458         unsigned long long cyc;
459 
460         cyc = (ns << data->cyc2ns_shift) / data->cyc2ns_mul;
461 
462         cyc2ns_read_end(data);
463         return cyc;
464 }
465 
466 static inline unsigned long cycles_2_us(unsigned long long cyc)
467 {
468         return cycles_2_ns(cyc) / NSEC_PER_USEC;
469 }
470 
471 static inline cycles_t sec_2_cycles(unsigned long sec)
472 {
473         return ns_2_cycles(sec * NSEC_PER_SEC);
474 }
475 
476 static inline unsigned long long usec_2_cycles(unsigned long usec)
477 {
478         return ns_2_cycles(usec * NSEC_PER_USEC);
479 }
480 
481 /*
482  * wait for all cpus on this hub to finish their sends and go quiet
483  * leaves uvhub_quiesce set so that no new broadcasts are started by
484  * bau_flush_send_and_wait()
485  */
486 static inline void quiesce_local_uvhub(struct bau_control *hmaster)
487 {
488         atom_asr(1, (struct atomic_short *)&hmaster->uvhub_quiesce);
489 }
490 
491 /*
492  * mark this quiet-requestor as done
493  */
494 static inline void end_uvhub_quiesce(struct bau_control *hmaster)
495 {
496         atom_asr(-1, (struct atomic_short *)&hmaster->uvhub_quiesce);
497 }
498 
499 static unsigned long uv1_read_status(unsigned long mmr_offset, int right_shift)
500 {
501         unsigned long descriptor_status;
502 
503         descriptor_status = uv_read_local_mmr(mmr_offset);
504         descriptor_status >>= right_shift;
505         descriptor_status &= UV_ACT_STATUS_MASK;
506         return descriptor_status;
507 }
508 
509 /*
510  * Wait for completion of a broadcast software ack message
511  * return COMPLETE, RETRY(PLUGGED or TIMEOUT) or GIVEUP
512  */
513 static int uv1_wait_completion(struct bau_desc *bau_desc,
514                                 unsigned long mmr_offset, int right_shift,
515                                 struct bau_control *bcp, long try)
516 {
517         unsigned long descriptor_status;
518         cycles_t ttm;
519         struct ptc_stats *stat = bcp->statp;
520 
521         descriptor_status = uv1_read_status(mmr_offset, right_shift);
522         /* spin on the status MMR, waiting for it to go idle */
523         while ((descriptor_status != DS_IDLE)) {
524                 /*
525                  * Our software ack messages may be blocked because
526                  * there are no swack resources available.  As long
527                  * as none of them has timed out hardware will NACK
528                  * our message and its state will stay IDLE.
529                  */
530                 if (descriptor_status == DS_SOURCE_TIMEOUT) {
531                         stat->s_stimeout++;
532                         return FLUSH_GIVEUP;
533                 } else if (descriptor_status == DS_DESTINATION_TIMEOUT) {
534                         stat->s_dtimeout++;
535                         ttm = get_cycles();
536 
537                         /*
538                          * Our retries may be blocked by all destination
539                          * swack resources being consumed, and a timeout
540                          * pending.  In that case hardware returns the
541                          * ERROR that looks like a destination timeout.
542                          */
543                         if (cycles_2_us(ttm - bcp->send_message) < timeout_us) {
544                                 bcp->conseccompletes = 0;
545                                 return FLUSH_RETRY_PLUGGED;
546                         }
547 
548                         bcp->conseccompletes = 0;
549                         return FLUSH_RETRY_TIMEOUT;
550                 } else {
551                         /*
552                          * descriptor_status is still BUSY
553                          */
554                         cpu_relax();
555                 }
556                 descriptor_status = uv1_read_status(mmr_offset, right_shift);
557         }
558         bcp->conseccompletes++;
559         return FLUSH_COMPLETE;
560 }
561 
562 /*
563  * UV2 could have an extra bit of status in the ACTIVATION_STATUS_2 register.
564  * But not currently used.
565  */
566 static unsigned long uv2_read_status(unsigned long offset, int rshft, int desc)
567 {
568         unsigned long descriptor_status;
569 
570         descriptor_status =
571                 ((read_lmmr(offset) >> rshft) & UV_ACT_STATUS_MASK) << 1;
572         return descriptor_status;
573 }
574 
575 /*
576  * Return whether the status of the descriptor that is normally used for this
577  * cpu (the one indexed by its hub-relative cpu number) is busy.
578  * The status of the original 32 descriptors is always reflected in the 64
579  * bits of UVH_LB_BAU_SB_ACTIVATION_STATUS_0.
580  * The bit provided by the activation_status_2 register is irrelevant to
581  * the status if it is only being tested for busy or not busy.
582  */
583 int normal_busy(struct bau_control *bcp)
584 {
585         int cpu = bcp->uvhub_cpu;
586         int mmr_offset;
587         int right_shift;
588 
589         mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_0;
590         right_shift = cpu * UV_ACT_STATUS_SIZE;
591         return (((((read_lmmr(mmr_offset) >> right_shift) &
592                                 UV_ACT_STATUS_MASK)) << 1) == UV2H_DESC_BUSY);
593 }
594 
595 /*
596  * Entered when a bau descriptor has gone into a permanent busy wait because
597  * of a hardware bug.
598  * Workaround the bug.
599  */
600 int handle_uv2_busy(struct bau_control *bcp)
601 {
602         struct ptc_stats *stat = bcp->statp;
603 
604         stat->s_uv2_wars++;
605         bcp->busy = 1;
606         return FLUSH_GIVEUP;
607 }
608 
609 static int uv2_wait_completion(struct bau_desc *bau_desc,
610                                 unsigned long mmr_offset, int right_shift,
611                                 struct bau_control *bcp, long try)
612 {
613         unsigned long descriptor_stat;
614         cycles_t ttm;
615         int desc = bcp->uvhub_cpu;
616         long busy_reps = 0;
617         struct ptc_stats *stat = bcp->statp;
618 
619         descriptor_stat = uv2_read_status(mmr_offset, right_shift, desc);
620 
621         /* spin on the status MMR, waiting for it to go idle */
622         while (descriptor_stat != UV2H_DESC_IDLE) {
623                 if ((descriptor_stat == UV2H_DESC_SOURCE_TIMEOUT)) {
624                         /*
625                          * A h/w bug on the destination side may
626                          * have prevented the message being marked
627                          * pending, thus it doesn't get replied to
628                          * and gets continually nacked until it times
629                          * out with a SOURCE_TIMEOUT.
630                          */
631                         stat->s_stimeout++;
632                         return FLUSH_GIVEUP;
633                 } else if (descriptor_stat == UV2H_DESC_DEST_TIMEOUT) {
634                         ttm = get_cycles();
635 
636                         /*
637                          * Our retries may be blocked by all destination
638                          * swack resources being consumed, and a timeout
639                          * pending.  In that case hardware returns the
640                          * ERROR that looks like a destination timeout.
641                          * Without using the extended status we have to
642                          * deduce from the short time that this was a
643                          * strong nack.
644                          */
645                         if (cycles_2_us(ttm - bcp->send_message) < timeout_us) {
646                                 bcp->conseccompletes = 0;
647                                 stat->s_plugged++;
648                                 /* FLUSH_RETRY_PLUGGED causes hang on boot */
649                                 return FLUSH_GIVEUP;
650                         }
651                         stat->s_dtimeout++;
652                         bcp->conseccompletes = 0;
653                         /* FLUSH_RETRY_TIMEOUT causes hang on boot */
654                         return FLUSH_GIVEUP;
655                 } else {
656                         busy_reps++;
657                         if (busy_reps > 1000000) {
658                                 /* not to hammer on the clock */
659                                 busy_reps = 0;
660                                 ttm = get_cycles();
661                                 if ((ttm - bcp->send_message) >
662                                                 bcp->timeout_interval)
663                                         return handle_uv2_busy(bcp);
664                         }
665                         /*
666                          * descriptor_stat is still BUSY
667                          */
668                         cpu_relax();
669                 }
670                 descriptor_stat = uv2_read_status(mmr_offset, right_shift,
671                                                                         desc);
672         }
673         bcp->conseccompletes++;
674         return FLUSH_COMPLETE;
675 }
676 
677 /*
678  * There are 2 status registers; each and array[32] of 2 bits. Set up for
679  * which register to read and position in that register based on cpu in
680  * current hub.
681  */
682 static int wait_completion(struct bau_desc *bau_desc,
683                                 struct bau_control *bcp, long try)
684 {
685         int right_shift;
686         unsigned long mmr_offset;
687         int desc = bcp->uvhub_cpu;
688 
689         if (desc < UV_CPUS_PER_AS) {
690                 mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_0;
691                 right_shift = desc * UV_ACT_STATUS_SIZE;
692         } else {
693                 mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_1;
694                 right_shift = ((desc - UV_CPUS_PER_AS) * UV_ACT_STATUS_SIZE);
695         }
696 
697         if (bcp->uvhub_version == 1)
698                 return uv1_wait_completion(bau_desc, mmr_offset, right_shift,
699                                                                 bcp, try);
700         else
701                 return uv2_wait_completion(bau_desc, mmr_offset, right_shift,
702                                                                 bcp, try);
703 }
704 
705 /*
706  * Our retries are blocked by all destination sw ack resources being
707  * in use, and a timeout is pending. In that case hardware immediately
708  * returns the ERROR that looks like a destination timeout.
709  */
710 static void destination_plugged(struct bau_desc *bau_desc,
711                         struct bau_control *bcp,
712                         struct bau_control *hmaster, struct ptc_stats *stat)
713 {
714         udelay(bcp->plugged_delay);
715         bcp->plugged_tries++;
716 
717         if (bcp->plugged_tries >= bcp->plugsb4reset) {
718                 bcp->plugged_tries = 0;
719 
720                 quiesce_local_uvhub(hmaster);
721 
722                 spin_lock(&hmaster->queue_lock);
723                 reset_with_ipi(&bau_desc->distribution, bcp);
724                 spin_unlock(&hmaster->queue_lock);
725 
726                 end_uvhub_quiesce(hmaster);
727 
728                 bcp->ipi_attempts++;
729                 stat->s_resets_plug++;
730         }
731 }
732 
733 static void destination_timeout(struct bau_desc *bau_desc,
734                         struct bau_control *bcp, struct bau_control *hmaster,
735                         struct ptc_stats *stat)
736 {
737         hmaster->max_concurr = 1;
738         bcp->timeout_tries++;
739         if (bcp->timeout_tries >= bcp->timeoutsb4reset) {
740                 bcp->timeout_tries = 0;
741 
742                 quiesce_local_uvhub(hmaster);
743 
744                 spin_lock(&hmaster->queue_lock);
745                 reset_with_ipi(&bau_desc->distribution, bcp);
746                 spin_unlock(&hmaster->queue_lock);
747 
748                 end_uvhub_quiesce(hmaster);
749 
750                 bcp->ipi_attempts++;
751                 stat->s_resets_timeout++;
752         }
753 }
754 
755 /*
756  * Stop all cpus on a uvhub from using the BAU for a period of time.
757  * This is reversed by check_enable.
758  */
759 static void disable_for_period(struct bau_control *bcp, struct ptc_stats *stat)
760 {
761         int tcpu;
762         struct bau_control *tbcp;
763         struct bau_control *hmaster;
764         cycles_t tm1;
765 
766         hmaster = bcp->uvhub_master;
767         spin_lock(&hmaster->disable_lock);
768         if (!bcp->baudisabled) {
769                 stat->s_bau_disabled++;
770                 tm1 = get_cycles();
771                 for_each_present_cpu(tcpu) {
772                         tbcp = &per_cpu(bau_control, tcpu);
773                         if (tbcp->uvhub_master == hmaster) {
774                                 tbcp->baudisabled = 1;
775                                 tbcp->set_bau_on_time =
776                                         tm1 + bcp->disabled_period;
777                         }
778                 }
779         }
780         spin_unlock(&hmaster->disable_lock);
781 }
782 
783 static void count_max_concurr(int stat, struct bau_control *bcp,
784                                 struct bau_control *hmaster)
785 {
786         bcp->plugged_tries = 0;
787         bcp->timeout_tries = 0;
788         if (stat != FLUSH_COMPLETE)
789                 return;
790         if (bcp->conseccompletes <= bcp->complete_threshold)
791                 return;
792         if (hmaster->max_concurr >= hmaster->max_concurr_const)
793                 return;
794         hmaster->max_concurr++;
795 }
796 
797 static void record_send_stats(cycles_t time1, cycles_t time2,
798                 struct bau_control *bcp, struct ptc_stats *stat,
799                 int completion_status, int try)
800 {
801         cycles_t elapsed;
802 
803         if (time2 > time1) {
804                 elapsed = time2 - time1;
805                 stat->s_time += elapsed;
806 
807                 if ((completion_status == FLUSH_COMPLETE) && (try == 1)) {
808                         bcp->period_requests++;
809                         bcp->period_time += elapsed;
810                         if ((elapsed > congested_cycles) &&
811                             (bcp->period_requests > bcp->cong_reps) &&
812                             ((bcp->period_time / bcp->period_requests) >
813                                                         congested_cycles)) {
814                                 stat->s_congested++;
815                                 disable_for_period(bcp, stat);
816                         }
817                 }
818         } else
819                 stat->s_requestor--;
820 
821         if (completion_status == FLUSH_COMPLETE && try > 1)
822                 stat->s_retriesok++;
823         else if (completion_status == FLUSH_GIVEUP) {
824                 stat->s_giveup++;
825                 if (get_cycles() > bcp->period_end)
826                         bcp->period_giveups = 0;
827                 bcp->period_giveups++;
828                 if (bcp->period_giveups == 1)
829                         bcp->period_end = get_cycles() + bcp->disabled_period;
830                 if (bcp->period_giveups > bcp->giveup_limit) {
831                         disable_for_period(bcp, stat);
832                         stat->s_giveuplimit++;
833                 }
834         }
835 }
836 
837 /*
838  * Because of a uv1 hardware bug only a limited number of concurrent
839  * requests can be made.
840  */
841 static void uv1_throttle(struct bau_control *hmaster, struct ptc_stats *stat)
842 {
843         spinlock_t *lock = &hmaster->uvhub_lock;
844         atomic_t *v;
845 
846         v = &hmaster->active_descriptor_count;
847         if (!atomic_inc_unless_ge(lock, v, hmaster->max_concurr)) {
848                 stat->s_throttles++;
849                 do {
850                         cpu_relax();
851                 } while (!atomic_inc_unless_ge(lock, v, hmaster->max_concurr));
852         }
853 }
854 
855 /*
856  * Handle the completion status of a message send.
857  */
858 static void handle_cmplt(int completion_status, struct bau_desc *bau_desc,
859                         struct bau_control *bcp, struct bau_control *hmaster,
860                         struct ptc_stats *stat)
861 {
862         if (completion_status == FLUSH_RETRY_PLUGGED)
863                 destination_plugged(bau_desc, bcp, hmaster, stat);
864         else if (completion_status == FLUSH_RETRY_TIMEOUT)
865                 destination_timeout(bau_desc, bcp, hmaster, stat);
866 }
867 
868 /*
869  * Send a broadcast and wait for it to complete.
870  *
871  * The flush_mask contains the cpus the broadcast is to be sent to including
872  * cpus that are on the local uvhub.
873  *
874  * Returns 0 if all flushing represented in the mask was done.
875  * Returns 1 if it gives up entirely and the original cpu mask is to be
876  * returned to the kernel.
877  */
878 int uv_flush_send_and_wait(struct cpumask *flush_mask, struct bau_control *bcp,
879         struct bau_desc *bau_desc)
880 {
881         int seq_number = 0;
882         int completion_stat = 0;
883         int uv1 = 0;
884         long try = 0;
885         unsigned long index;
886         cycles_t time1;
887         cycles_t time2;
888         struct ptc_stats *stat = bcp->statp;
889         struct bau_control *hmaster = bcp->uvhub_master;
890         struct uv1_bau_msg_header *uv1_hdr = NULL;
891         struct uv2_bau_msg_header *uv2_hdr = NULL;
892 
893         if (bcp->uvhub_version == 1) {
894                 uv1 = 1;
895                 uv1_throttle(hmaster, stat);
896         }
897 
898         while (hmaster->uvhub_quiesce)
899                 cpu_relax();
900 
901         time1 = get_cycles();
902         if (uv1)
903                 uv1_hdr = &bau_desc->header.uv1_hdr;
904         else
905                 uv2_hdr = &bau_desc->header.uv2_hdr;
906 
907         do {
908                 if (try == 0) {
909                         if (uv1)
910                                 uv1_hdr->msg_type = MSG_REGULAR;
911                         else
912                                 uv2_hdr->msg_type = MSG_REGULAR;
913                         seq_number = bcp->message_number++;
914                 } else {
915                         if (uv1)
916                                 uv1_hdr->msg_type = MSG_RETRY;
917                         else
918                                 uv2_hdr->msg_type = MSG_RETRY;
919                         stat->s_retry_messages++;
920                 }
921 
922                 if (uv1)
923                         uv1_hdr->sequence = seq_number;
924                 else
925                         uv2_hdr->sequence = seq_number;
926                 index = (1UL << AS_PUSH_SHIFT) | bcp->uvhub_cpu;
927                 bcp->send_message = get_cycles();
928 
929                 write_mmr_activation(index);
930 
931                 try++;
932                 completion_stat = wait_completion(bau_desc, bcp, try);
933 
934                 handle_cmplt(completion_stat, bau_desc, bcp, hmaster, stat);
935 
936                 if (bcp->ipi_attempts >= bcp->ipi_reset_limit) {
937                         bcp->ipi_attempts = 0;
938                         stat->s_overipilimit++;
939                         completion_stat = FLUSH_GIVEUP;
940                         break;
941                 }
942                 cpu_relax();
943         } while ((completion_stat == FLUSH_RETRY_PLUGGED) ||
944                  (completion_stat == FLUSH_RETRY_TIMEOUT));
945 
946         time2 = get_cycles();
947 
948         count_max_concurr(completion_stat, bcp, hmaster);
949 
950         while (hmaster->uvhub_quiesce)
951                 cpu_relax();
952 
953         atomic_dec(&hmaster->active_descriptor_count);
954 
955         record_send_stats(time1, time2, bcp, stat, completion_stat, try);
956 
957         if (completion_stat == FLUSH_GIVEUP)
958                 /* FLUSH_GIVEUP will fall back to using IPI's for tlb flush */
959                 return 1;
960         return 0;
961 }
962 
963 /*
964  * The BAU is disabled for this uvhub. When the disabled time period has
965  * expired re-enable it.
966  * Return 0 if it is re-enabled for all cpus on this uvhub.
967  */
968 static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
969 {
970         int tcpu;
971         struct bau_control *tbcp;
972         struct bau_control *hmaster;
973 
974         hmaster = bcp->uvhub_master;
975         spin_lock(&hmaster->disable_lock);
976         if (bcp->baudisabled && (get_cycles() >= bcp->set_bau_on_time)) {
977                 stat->s_bau_reenabled++;
978                 for_each_present_cpu(tcpu) {
979                         tbcp = &per_cpu(bau_control, tcpu);
980                         if (tbcp->uvhub_master == hmaster) {
981                                 tbcp->baudisabled = 0;
982                                 tbcp->period_requests = 0;
983                                 tbcp->period_time = 0;
984                                 tbcp->period_giveups = 0;
985                         }
986                 }
987                 spin_unlock(&hmaster->disable_lock);
988                 return 0;
989         }
990         spin_unlock(&hmaster->disable_lock);
991         return -1;
992 }
993 
994 static void record_send_statistics(struct ptc_stats *stat, int locals, int hubs,
995                                 int remotes, struct bau_desc *bau_desc)
996 {
997         stat->s_requestor++;
998         stat->s_ntargcpu += remotes + locals;
999         stat->s_ntargremotes += remotes;
1000         stat->s_ntarglocals += locals;
1001 
1002         /* uvhub statistics */
1003         hubs = bau_uvhub_weight(&bau_desc->distribution);
1004         if (locals) {
1005                 stat->s_ntarglocaluvhub++;
1006                 stat->s_ntargremoteuvhub += (hubs - 1);
1007         } else
1008                 stat->s_ntargremoteuvhub += hubs;
1009 
1010         stat->s_ntarguvhub += hubs;
1011 
1012         if (hubs >= 16)
1013                 stat->s_ntarguvhub16++;
1014         else if (hubs >= 8)
1015                 stat->s_ntarguvhub8++;
1016         else if (hubs >= 4)
1017                 stat->s_ntarguvhub4++;
1018         else if (hubs >= 2)
1019                 stat->s_ntarguvhub2++;
1020         else
1021                 stat->s_ntarguvhub1++;
1022 }
1023 
1024 /*
1025  * Translate a cpu mask to the uvhub distribution mask in the BAU
1026  * activation descriptor.
1027  */
1028 static int set_distrib_bits(struct cpumask *flush_mask, struct bau_control *bcp,
1029                         struct bau_desc *bau_desc, int *localsp, int *remotesp)
1030 {
1031         int cpu;
1032         int pnode;
1033         int cnt = 0;
1034         struct hub_and_pnode *hpp;
1035 
1036         for_each_cpu(cpu, flush_mask) {
1037                 /*
1038                  * The distribution vector is a bit map of pnodes, relative
1039                  * to the partition base pnode (and the partition base nasid
1040                  * in the header).
1041                  * Translate cpu to pnode and hub using a local memory array.
1042                  */
1043                 hpp = &bcp->socket_master->thp[cpu];
1044                 pnode = hpp->pnode - bcp->partition_base_pnode;
1045                 bau_uvhub_set(pnode, &bau_desc->distribution);
1046                 cnt++;
1047                 if (hpp->uvhub == bcp->uvhub)
1048                         (*localsp)++;
1049                 else
1050                         (*remotesp)++;
1051         }
1052         if (!cnt)
1053                 return 1;
1054         return 0;
1055 }
1056 
1057 /*
1058  * globally purge translation cache of a virtual address or all TLB's
1059  * @cpumask: mask of all cpu's in which the address is to be removed
1060  * @mm: mm_struct containing virtual address range
1061  * @start: start virtual address to be removed from TLB
1062  * @end: end virtual address to be remove from TLB
1063  * @cpu: the current cpu
1064  *
1065  * This is the entry point for initiating any UV global TLB shootdown.
1066  *
1067  * Purges the translation caches of all specified processors of the given
1068  * virtual address, or purges all TLB's on specified processors.
1069  *
1070  * The caller has derived the cpumask from the mm_struct.  This function
1071  * is called only if there are bits set in the mask. (e.g. flush_tlb_page())
1072  *
1073  * The cpumask is converted into a uvhubmask of the uvhubs containing
1074  * those cpus.
1075  *
1076  * Note that this function should be called with preemption disabled.
1077  *
1078  * Returns NULL if all remote flushing was done.
1079  * Returns pointer to cpumask if some remote flushing remains to be
1080  * done.  The returned pointer is valid till preemption is re-enabled.
1081  */
1082 const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
1083                                 struct mm_struct *mm, unsigned long start,
1084                                 unsigned long end, unsigned int cpu)
1085 {
1086         int locals = 0;
1087         int remotes = 0;
1088         int hubs = 0;
1089         struct bau_desc *bau_desc;
1090         struct cpumask *flush_mask;
1091         struct ptc_stats *stat;
1092         struct bau_control *bcp;
1093         unsigned long descriptor_status;
1094         unsigned long status;
1095 
1096         bcp = &per_cpu(bau_control, cpu);
1097 
1098         if (bcp->nobau)
1099                 return cpumask;
1100 
1101         stat = bcp->statp;
1102         stat->s_enters++;
1103 
1104         if (bcp->busy) {
1105                 descriptor_status =
1106                         read_lmmr(UVH_LB_BAU_SB_ACTIVATION_STATUS_0);
1107                 status = ((descriptor_status >> (bcp->uvhub_cpu *
1108                         UV_ACT_STATUS_SIZE)) & UV_ACT_STATUS_MASK) << 1;
1109                 if (status == UV2H_DESC_BUSY)
1110                         return cpumask;
1111                 bcp->busy = 0;
1112         }
1113 
1114         /* bau was disabled due to slow response */
1115         if (bcp->baudisabled) {
1116                 if (check_enable(bcp, stat)) {
1117                         stat->s_ipifordisabled++;
1118                         return cpumask;
1119                 }
1120         }
1121 
1122         /*
1123          * Each sending cpu has a per-cpu mask which it fills from the caller's
1124          * cpu mask.  All cpus are converted to uvhubs and copied to the
1125          * activation descriptor.
1126          */
1127         flush_mask = (struct cpumask *)per_cpu(uv_flush_tlb_mask, cpu);
1128         /* don't actually do a shootdown of the local cpu */
1129         cpumask_andnot(flush_mask, cpumask, cpumask_of(cpu));
1130 
1131         if (cpu_isset(cpu, *cpumask))
1132                 stat->s_ntargself++;
1133 
1134         bau_desc = bcp->descriptor_base;
1135         bau_desc += (ITEMS_PER_DESC * bcp->uvhub_cpu);
1136         bau_uvhubs_clear(&bau_desc->distribution, UV_DISTRIBUTION_SIZE);
1137         if (set_distrib_bits(flush_mask, bcp, bau_desc, &locals, &remotes))
1138                 return NULL;
1139 
1140         record_send_statistics(stat, locals, hubs, remotes, bau_desc);
1141 
1142         if (!end || (end - start) <= PAGE_SIZE)
1143                 bau_desc->payload.address = start;
1144         else
1145                 bau_desc->payload.address = TLB_FLUSH_ALL;
1146         bau_desc->payload.sending_cpu = cpu;
1147         /*
1148          * uv_flush_send_and_wait returns 0 if all cpu's were messaged,
1149          * or 1 if it gave up and the original cpumask should be returned.
1150          */
1151         if (!uv_flush_send_and_wait(flush_mask, bcp, bau_desc))
1152                 return NULL;
1153         else
1154                 return cpumask;
1155 }
1156 
1157 /*
1158  * Search the message queue for any 'other' unprocessed message with the
1159  * same software acknowledge resource bit vector as the 'msg' message.
1160  */
1161 struct bau_pq_entry *find_another_by_swack(struct bau_pq_entry *msg,
1162                                            struct bau_control *bcp)
1163 {
1164         struct bau_pq_entry *msg_next = msg + 1;
1165         unsigned char swack_vec = msg->swack_vec;
1166 
1167         if (msg_next > bcp->queue_last)
1168                 msg_next = bcp->queue_first;
1169         while (msg_next != msg) {
1170                 if ((msg_next->canceled == 0) && (msg_next->replied_to == 0) &&
1171                                 (msg_next->swack_vec == swack_vec))
1172                         return msg_next;
1173                 msg_next++;
1174                 if (msg_next > bcp->queue_last)
1175                         msg_next = bcp->queue_first;
1176         }
1177         return NULL;
1178 }
1179 
1180 /*
1181  * UV2 needs to work around a bug in which an arriving message has not
1182  * set a bit in the UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE register.
1183  * Such a message must be ignored.
1184  */
1185 void process_uv2_message(struct msg_desc *mdp, struct bau_control *bcp)
1186 {
1187         unsigned long mmr_image;
1188         unsigned char swack_vec;
1189         struct bau_pq_entry *msg = mdp->msg;
1190         struct bau_pq_entry *other_msg;
1191 
1192         mmr_image = read_mmr_sw_ack();
1193         swack_vec = msg->swack_vec;
1194 
1195         if ((swack_vec & mmr_image) == 0) {
1196                 /*
1197                  * This message was assigned a swack resource, but no
1198                  * reserved acknowlegment is pending.
1199                  * The bug has prevented this message from setting the MMR.
1200                  */
1201                 /*
1202                  * Some message has set the MMR 'pending' bit; it might have
1203                  * been another message.  Look for that message.
1204                  */
1205                 other_msg = find_another_by_swack(msg, bcp);
1206                 if (other_msg) {
1207                         /*
1208                          * There is another. Process this one but do not
1209                          * ack it.
1210                          */
1211                         bau_process_message(mdp, bcp, 0);
1212                         /*
1213                          * Let the natural processing of that other message
1214                          * acknowledge it. Don't get the processing of sw_ack's
1215                          * out of order.
1216                          */
1217                         return;
1218                 }
1219         }
1220 
1221         /*
1222          * Either the MMR shows this one pending a reply or there is no
1223          * other message using this sw_ack, so it is safe to acknowledge it.
1224          */
1225         bau_process_message(mdp, bcp, 1);
1226 
1227         return;
1228 }
1229 
1230 /*
1231  * The BAU message interrupt comes here. (registered by set_intr_gate)
1232  * See entry_64.S
1233  *
1234  * We received a broadcast assist message.
1235  *
1236  * Interrupts are disabled; this interrupt could represent
1237  * the receipt of several messages.
1238  *
1239  * All cores/threads on this hub get this interrupt.
1240  * The last one to see it does the software ack.
1241  * (the resource will not be freed until noninterruptable cpus see this
1242  *  interrupt; hardware may timeout the s/w ack and reply ERROR)
1243  */
1244 void uv_bau_message_interrupt(struct pt_regs *regs)
1245 {
1246         int count = 0;
1247         cycles_t time_start;
1248         struct bau_pq_entry *msg;
1249         struct bau_control *bcp;
1250         struct ptc_stats *stat;
1251         struct msg_desc msgdesc;
1252 
1253         ack_APIC_irq();
1254         time_start = get_cycles();
1255 
1256         bcp = &per_cpu(bau_control, smp_processor_id());
1257         stat = bcp->statp;
1258 
1259         msgdesc.queue_first = bcp->queue_first;
1260         msgdesc.queue_last = bcp->queue_last;
1261 
1262         msg = bcp->bau_msg_head;
1263         while (msg->swack_vec) {
1264                 count++;
1265 
1266                 msgdesc.msg_slot = msg - msgdesc.queue_first;
1267                 msgdesc.msg = msg;
1268                 if (bcp->uvhub_version == 2)
1269                         process_uv2_message(&msgdesc, bcp);
1270                 else
1271                         bau_process_message(&msgdesc, bcp, 1);
1272 
1273                 msg++;
1274                 if (msg > msgdesc.queue_last)
1275                         msg = msgdesc.queue_first;
1276                 bcp->bau_msg_head = msg;
1277         }
1278         stat->d_time += (get_cycles() - time_start);
1279         if (!count)
1280                 stat->d_nomsg++;
1281         else if (count > 1)
1282                 stat->d_multmsg++;
1283 }
1284 
1285 /*
1286  * Each target uvhub (i.e. a uvhub that has cpu's) needs to have
1287  * shootdown message timeouts enabled.  The timeout does not cause
1288  * an interrupt, but causes an error message to be returned to
1289  * the sender.
1290  */
1291 static void __init enable_timeouts(void)
1292 {
1293         int uvhub;
1294         int nuvhubs;
1295         int pnode;
1296         unsigned long mmr_image;
1297 
1298         nuvhubs = uv_num_possible_blades();
1299 
1300         for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
1301                 if (!uv_blade_nr_possible_cpus(uvhub))
1302                         continue;
1303 
1304                 pnode = uv_blade_to_pnode(uvhub);
1305                 mmr_image = read_mmr_misc_control(pnode);
1306                 /*
1307                  * Set the timeout period and then lock it in, in three
1308                  * steps; captures and locks in the period.
1309                  *
1310                  * To program the period, the SOFT_ACK_MODE must be off.
1311                  */
1312                 mmr_image &= ~(1L << SOFTACK_MSHIFT);
1313                 write_mmr_misc_control(pnode, mmr_image);
1314                 /*
1315                  * Set the 4-bit period.
1316                  */
1317                 mmr_image &= ~((unsigned long)0xf << SOFTACK_PSHIFT);
1318                 mmr_image |= (SOFTACK_TIMEOUT_PERIOD << SOFTACK_PSHIFT);
1319                 write_mmr_misc_control(pnode, mmr_image);
1320                 /*
1321                  * UV1:
1322                  * Subsequent reversals of the timebase bit (3) cause an
1323                  * immediate timeout of one or all INTD resources as
1324                  * indicated in bits 2:0 (7 causes all of them to timeout).
1325                  */
1326                 mmr_image |= (1L << SOFTACK_MSHIFT);
1327                 if (is_uv2_hub()) {
1328                         /* hw bug workaround; do not use extended status */
1329                         mmr_image &= ~(1L << UV2_EXT_SHFT);
1330                 }
1331                 write_mmr_misc_control(pnode, mmr_image);
1332         }
1333 }
1334 
1335 static void *ptc_seq_start(struct seq_file *file, loff_t *offset)
1336 {
1337         if (*offset < num_possible_cpus())
1338                 return offset;
1339         return NULL;
1340 }
1341 
1342 static void *ptc_seq_next(struct seq_file *file, void *data, loff_t *offset)
1343 {
1344         (*offset)++;
1345         if (*offset < num_possible_cpus())
1346                 return offset;
1347         return NULL;
1348 }
1349 
1350 static void ptc_seq_stop(struct seq_file *file, void *data)
1351 {
1352 }
1353 
1354 /*
1355  * Display the statistics thru /proc/sgi_uv/ptc_statistics
1356  * 'data' points to the cpu number
1357  * Note: see the descriptions in stat_description[].
1358  */
1359 static int ptc_seq_show(struct seq_file *file, void *data)
1360 {
1361         struct ptc_stats *stat;
1362         struct bau_control *bcp;
1363         int cpu;
1364 
1365         cpu = *(loff_t *)data;
1366         if (!cpu) {
1367                 seq_printf(file,
1368                  "# cpu bauoff sent stime self locals remotes ncpus localhub ");
1369                 seq_printf(file,
1370                         "remotehub numuvhubs numuvhubs16 numuvhubs8 ");
1371                 seq_printf(file,
1372                         "numuvhubs4 numuvhubs2 numuvhubs1 dto snacks retries ");
1373                 seq_printf(file,
1374                         "rok resetp resett giveup sto bz throt disable ");
1375                 seq_printf(file,
1376                         "enable wars warshw warwaits enters ipidis plugged ");
1377                 seq_printf(file,
1378                         "ipiover glim cong swack recv rtime all one mult ");
1379                 seq_printf(file,
1380                         "none retry canc nocan reset rcan\n");
1381         }
1382         if (cpu < num_possible_cpus() && cpu_online(cpu)) {
1383                 bcp = &per_cpu(bau_control, cpu);
1384                 stat = bcp->statp;
1385                 /* source side statistics */
1386                 seq_printf(file,
1387                         "cpu %d %d %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
1388                            cpu, bcp->nobau, stat->s_requestor,
1389                            cycles_2_us(stat->s_time),
1390                            stat->s_ntargself, stat->s_ntarglocals,
1391                            stat->s_ntargremotes, stat->s_ntargcpu,
1392                            stat->s_ntarglocaluvhub, stat->s_ntargremoteuvhub,
1393                            stat->s_ntarguvhub, stat->s_ntarguvhub16);
1394                 seq_printf(file, "%ld %ld %ld %ld %ld %ld ",
1395                            stat->s_ntarguvhub8, stat->s_ntarguvhub4,
1396                            stat->s_ntarguvhub2, stat->s_ntarguvhub1,
1397                            stat->s_dtimeout, stat->s_strongnacks);
1398                 seq_printf(file, "%ld %ld %ld %ld %ld %ld %ld %ld ",
1399                            stat->s_retry_messages, stat->s_retriesok,
1400                            stat->s_resets_plug, stat->s_resets_timeout,
1401                            stat->s_giveup, stat->s_stimeout,
1402                            stat->s_busy, stat->s_throttles);
1403                 seq_printf(file, "%ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
1404                            stat->s_bau_disabled, stat->s_bau_reenabled,
1405                            stat->s_uv2_wars, stat->s_uv2_wars_hw,
1406                            stat->s_uv2_war_waits, stat->s_enters,
1407                            stat->s_ipifordisabled, stat->s_plugged,
1408                            stat->s_overipilimit, stat->s_giveuplimit,
1409                            stat->s_congested);
1410 
1411                 /* destination side statistics */
1412                 seq_printf(file,
1413                         "%lx %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld\n",
1414                            read_gmmr_sw_ack(uv_cpu_to_pnode(cpu)),
1415                            stat->d_requestee, cycles_2_us(stat->d_time),
1416                            stat->d_alltlb, stat->d_onetlb, stat->d_multmsg,
1417                            stat->d_nomsg, stat->d_retries, stat->d_canceled,
1418                            stat->d_nocanceled, stat->d_resets,
1419                            stat->d_rcanceled);
1420         }
1421         return 0;
1422 }
1423 
1424 /*
1425  * Display the tunables thru debugfs
1426  */
1427 static ssize_t tunables_read(struct file *file, char __user *userbuf,
1428                                 size_t count, loff_t *ppos)
1429 {
1430         char *buf;
1431         int ret;
1432 
1433         buf = kasprintf(GFP_KERNEL, "%s %s %s\n%d %d %d %d %d %d %d %d %d %d\n",
1434                 "max_concur plugged_delay plugsb4reset timeoutsb4reset",
1435                 "ipi_reset_limit complete_threshold congested_response_us",
1436                 "congested_reps disabled_period giveup_limit",
1437                 max_concurr, plugged_delay, plugsb4reset,
1438                 timeoutsb4reset, ipi_reset_limit, complete_threshold,
1439                 congested_respns_us, congested_reps, disabled_period,
1440                 giveup_limit);
1441 
1442         if (!buf)
1443                 return -ENOMEM;
1444 
1445         ret = simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
1446         kfree(buf);
1447         return ret;
1448 }
1449 
1450 /*
1451  * handle a write to /proc/sgi_uv/ptc_statistics
1452  * -1: reset the statistics
1453  *  0: display meaning of the statistics
1454  */
1455 static ssize_t ptc_proc_write(struct file *file, const char __user *user,
1456                                 size_t count, loff_t *data)
1457 {
1458         int cpu;
1459         int i;
1460         int elements;
1461         long input_arg;
1462         char optstr[64];
1463         struct ptc_stats *stat;
1464 
1465         if (count == 0 || count > sizeof(optstr))
1466                 return -EINVAL;
1467         if (copy_from_user(optstr, user, count))
1468                 return -EFAULT;
1469         optstr[count - 1] = '\0';
1470 
1471         if (!strcmp(optstr, "on")) {
1472                 set_bau_on();
1473                 return count;
1474         } else if (!strcmp(optstr, "off")) {
1475                 set_bau_off();
1476                 return count;
1477         }
1478 
1479         if (strict_strtol(optstr, 10, &input_arg) < 0) {
1480                 printk(KERN_DEBUG "%s is invalid\n", optstr);
1481                 return -EINVAL;
1482         }
1483 
1484         if (input_arg == 0) {
1485                 elements = ARRAY_SIZE(stat_description);
1486                 printk(KERN_DEBUG "# cpu:      cpu number\n");
1487                 printk(KERN_DEBUG "Sender statistics:\n");
1488                 for (i = 0; i < elements; i++)
1489                         printk(KERN_DEBUG "%s\n", stat_description[i]);
1490         } else if (input_arg == -1) {
1491                 for_each_present_cpu(cpu) {
1492                         stat = &per_cpu(ptcstats, cpu);
1493                         memset(stat, 0, sizeof(struct ptc_stats));
1494                 }
1495         }
1496 
1497         return count;
1498 }
1499 
1500 static int local_atoi(const char *name)
1501 {
1502         int val = 0;
1503 
1504         for (;; name++) {
1505                 switch (*name) {
1506                 case '' ... '9':
1507                         val = 10*val+(*name-'');
1508                         break;
1509                 default:
1510                         return val;
1511                 }
1512         }
1513 }
1514 
1515 /*
1516  * Parse the values written to /sys/kernel/debug/sgi_uv/bau_tunables.
1517  * Zero values reset them to defaults.
1518  */
1519 static int parse_tunables_write(struct bau_control *bcp, char *instr,
1520                                 int count)
1521 {
1522         char *p;
1523         char *q;
1524         int cnt = 0;
1525         int val;
1526         int e = ARRAY_SIZE(tunables);
1527 
1528         p = instr + strspn(instr, WHITESPACE);
1529         q = p;
1530         for (; *p; p = q + strspn(q, WHITESPACE)) {
1531                 q = p + strcspn(p, WHITESPACE);
1532                 cnt++;
1533                 if (q == p)
1534                         break;
1535         }
1536         if (cnt != e) {
1537                 printk(KERN_INFO "bau tunable error: should be %d values\n", e);
1538                 return -EINVAL;
1539         }
1540 
1541         p = instr + strspn(instr, WHITESPACE);
1542         q = p;
1543         for (cnt = 0; *p; p = q + strspn(q, WHITESPACE), cnt++) {
1544                 q = p + strcspn(p, WHITESPACE);
1545                 val = local_atoi(p);
1546                 switch (cnt) {
1547                 case 0:
1548                         if (val == 0) {
1549                                 max_concurr = MAX_BAU_CONCURRENT;
1550                                 max_concurr_const = MAX_BAU_CONCURRENT;
1551                                 continue;
1552                         }
1553                         if (val < 1 || val > bcp->cpus_in_uvhub) {
1554                                 printk(KERN_DEBUG
1555                                 "Error: BAU max concurrent %d is invalid\n",
1556                                 val);
1557                                 return -EINVAL;
1558                         }
1559                         max_concurr = val;
1560                         max_concurr_const = val;
1561                         continue;
1562                 default:
1563                         if (val == 0)
1564                                 *tunables[cnt].tunp = tunables[cnt].deflt;
1565                         else
1566                                 *tunables[cnt].tunp = val;
1567                         continue;
1568                 }
1569                 if (q == p)
1570                         break;
1571         }
1572         return 0;
1573 }
1574 
1575 /*
1576  * Handle a write to debugfs. (/sys/kernel/debug/sgi_uv/bau_tunables)
1577  */
1578 static ssize_t tunables_write(struct file *file, const char __user *user,
1579                                 size_t count, loff_t *data)
1580 {
1581         int cpu;
1582         int ret;
1583         char instr[100];
1584         struct bau_control *bcp;
1585 
1586         if (count == 0 || count > sizeof(instr)-1)
1587                 return -EINVAL;
1588         if (copy_from_user(instr, user, count))
1589                 return -EFAULT;
1590 
1591         instr[count] = '\0';
1592 
1593         cpu = get_cpu();
1594         bcp = &per_cpu(bau_control, cpu);
1595         ret = parse_tunables_write(bcp, instr, count);
1596         put_cpu();
1597         if (ret)
1598                 return ret;
1599 
1600         for_each_present_cpu(cpu) {
1601                 bcp = &per_cpu(bau_control, cpu);
1602                 bcp->max_concurr =              max_concurr;
1603                 bcp->max_concurr_const =        max_concurr;
1604                 bcp->plugged_delay =            plugged_delay;
1605                 bcp->plugsb4reset =             plugsb4reset;
1606                 bcp->timeoutsb4reset =          timeoutsb4reset;
1607                 bcp->ipi_reset_limit =          ipi_reset_limit;
1608                 bcp->complete_threshold =       complete_threshold;
1609                 bcp->cong_response_us =         congested_respns_us;
1610                 bcp->cong_reps =                congested_reps;
1611                 bcp->disabled_period =          sec_2_cycles(disabled_period);
1612                 bcp->giveup_limit =             giveup_limit;
1613         }
1614         return count;
1615 }
1616 
1617 static const struct seq_operations uv_ptc_seq_ops = {
1618         .start          = ptc_seq_start,
1619         .next           = ptc_seq_next,
1620         .stop           = ptc_seq_stop,
1621         .show           = ptc_seq_show
1622 };
1623 
1624 static int ptc_proc_open(struct inode *inode, struct file *file)
1625 {
1626         return seq_open(file, &uv_ptc_seq_ops);
1627 }
1628 
1629 static int tunables_open(struct inode *inode, struct file *file)
1630 {
1631         return 0;
1632 }
1633 
1634 static const struct file_operations proc_uv_ptc_operations = {
1635         .open           = ptc_proc_open,
1636         .read           = seq_read,
1637         .write          = ptc_proc_write,
1638         .llseek         = seq_lseek,
1639         .release        = seq_release,
1640 };
1641 
1642 static const struct file_operations tunables_fops = {
1643         .open           = tunables_open,
1644         .read           = tunables_read,
1645         .write          = tunables_write,
1646         .llseek         = default_llseek,
1647 };
1648 
1649 static int __init uv_ptc_init(void)
1650 {
1651         struct proc_dir_entry *proc_uv_ptc;
1652 
1653         if (!is_uv_system())
1654                 return 0;
1655 
1656         proc_uv_ptc = proc_create(UV_PTC_BASENAME, 0444, NULL,
1657                                   &proc_uv_ptc_operations);
1658         if (!proc_uv_ptc) {
1659                 printk(KERN_ERR "unable to create %s proc entry\n",
1660                        UV_PTC_BASENAME);
1661                 return -EINVAL;
1662         }
1663 
1664         tunables_dir = debugfs_create_dir(UV_BAU_TUNABLES_DIR, NULL);
1665         if (!tunables_dir) {
1666                 printk(KERN_ERR "unable to create debugfs directory %s\n",
1667                        UV_BAU_TUNABLES_DIR);
1668                 return -EINVAL;
1669         }
1670         tunables_file = debugfs_create_file(UV_BAU_TUNABLES_FILE, 0600,
1671                                         tunables_dir, NULL, &tunables_fops);
1672         if (!tunables_file) {
1673                 printk(KERN_ERR "unable to create debugfs file %s\n",
1674                        UV_BAU_TUNABLES_FILE);
1675                 return -EINVAL;
1676         }
1677         return 0;
1678 }
1679 
1680 /*
1681  * Initialize the sending side's sending buffers.
1682  */
1683 static void activation_descriptor_init(int node, int pnode, int base_pnode)
1684 {
1685         int i;
1686         int cpu;
1687         int uv1 = 0;
1688         unsigned long gpa;
1689         unsigned long m;
1690         unsigned long n;
1691         size_t dsize;
1692         struct bau_desc *bau_desc;
1693         struct bau_desc *bd2;
1694         struct uv1_bau_msg_header *uv1_hdr;
1695         struct uv2_bau_msg_header *uv2_hdr;
1696         struct bau_control *bcp;
1697 
1698         /*
1699          * each bau_desc is 64 bytes; there are 8 (ITEMS_PER_DESC)
1700          * per cpu; and one per cpu on the uvhub (ADP_SZ)
1701          */
1702         dsize = sizeof(struct bau_desc) * ADP_SZ * ITEMS_PER_DESC;
1703         bau_desc = kmalloc_node(dsize, GFP_KERNEL, node);
1704         BUG_ON(!bau_desc);
1705 
1706         gpa = uv_gpa(bau_desc);
1707         n = uv_gpa_to_gnode(gpa);
1708         m = uv_gpa_to_offset(gpa);
1709         if (is_uv1_hub())
1710                 uv1 = 1;
1711 
1712         /* the 14-bit pnode */
1713         write_mmr_descriptor_base(pnode, (n << UV_DESC_PSHIFT | m));
1714         /*
1715          * Initializing all 8 (ITEMS_PER_DESC) descriptors for each
1716          * cpu even though we only use the first one; one descriptor can
1717          * describe a broadcast to 256 uv hubs.
1718          */
1719         for (i = 0, bd2 = bau_desc; i < (ADP_SZ * ITEMS_PER_DESC); i++, bd2++) {
1720                 memset(bd2, 0, sizeof(struct bau_desc));
1721                 if (uv1) {
1722                         uv1_hdr = &bd2->header.uv1_hdr;
1723                         uv1_hdr->swack_flag =   1;
1724                         /*
1725                          * The base_dest_nasid set in the message header
1726                          * is the nasid of the first uvhub in the partition.
1727                          * The bit map will indicate destination pnode numbers
1728                          * relative to that base. They may not be consecutive
1729                          * if nasid striding is being used.
1730                          */
1731                         uv1_hdr->base_dest_nasid =
1732                                                 UV_PNODE_TO_NASID(base_pnode);
1733                         uv1_hdr->dest_subnodeid =       UV_LB_SUBNODEID;
1734                         uv1_hdr->command =              UV_NET_ENDPOINT_INTD;
1735                         uv1_hdr->int_both =             1;
1736                         /*
1737                          * all others need to be set to zero:
1738                          *   fairness chaining multilevel count replied_to
1739                          */
1740                 } else {
1741                         /*
1742                          * BIOS uses legacy mode, but UV2 hardware always
1743                          * uses native mode for selective broadcasts.
1744                          */
1745                         uv2_hdr = &bd2->header.uv2_hdr;
1746                         uv2_hdr->swack_flag =   1;
1747                         uv2_hdr->base_dest_nasid =
1748                                                 UV_PNODE_TO_NASID(base_pnode);
1749                         uv2_hdr->dest_subnodeid =       UV_LB_SUBNODEID;
1750                         uv2_hdr->command =              UV_NET_ENDPOINT_INTD;
1751                 }
1752         }
1753         for_each_present_cpu(cpu) {
1754                 if (pnode != uv_blade_to_pnode(uv_cpu_to_blade_id(cpu)))
1755                         continue;
1756                 bcp = &per_cpu(bau_control, cpu);
1757                 bcp->descriptor_base = bau_desc;
1758         }
1759 }
1760 
1761 /*
1762  * initialize the destination side's receiving buffers
1763  * entered for each uvhub in the partition
1764  * - node is first node (kernel memory notion) on the uvhub
1765  * - pnode is the uvhub's physical identifier
1766  */
1767 static void pq_init(int node, int pnode)
1768 {
1769         int cpu;
1770         size_t plsize;
1771         char *cp;
1772         void *vp;
1773         unsigned long pn;
1774         unsigned long first;
1775         unsigned long pn_first;
1776         unsigned long last;
1777         struct bau_pq_entry *pqp;
1778         struct bau_control *bcp;
1779 
1780         plsize = (DEST_Q_SIZE + 1) * sizeof(struct bau_pq_entry);
1781         vp = kmalloc_node(plsize, GFP_KERNEL, node);
1782         pqp = (struct bau_pq_entry *)vp;
1783         BUG_ON(!pqp);
1784 
1785         cp = (char *)pqp + 31;
1786         pqp = (struct bau_pq_entry *)(((unsigned long)cp >> 5) << 5);
1787 
1788         for_each_present_cpu(cpu) {
1789                 if (pnode != uv_cpu_to_pnode(cpu))
1790                         continue;
1791                 /* for every cpu on this pnode: */
1792                 bcp = &per_cpu(bau_control, cpu);
1793                 bcp->queue_first        = pqp;
1794                 bcp->bau_msg_head       = pqp;
1795                 bcp->queue_last         = pqp + (DEST_Q_SIZE - 1);
1796         }
1797         /*
1798          * need the gnode of where the memory was really allocated
1799          */
1800         pn = uv_gpa_to_gnode(uv_gpa(pqp));
1801         first = uv_physnodeaddr(pqp);
1802         pn_first = ((unsigned long)pn << UV_PAYLOADQ_PNODE_SHIFT) | first;
1803         last = uv_physnodeaddr(pqp + (DEST_Q_SIZE - 1));
1804         write_mmr_payload_first(pnode, pn_first);
1805         write_mmr_payload_tail(pnode, first);
1806         write_mmr_payload_last(pnode, last);
1807         write_gmmr_sw_ack(pnode, 0xffffUL);
1808 
1809         /* in effect, all msg_type's are set to MSG_NOOP */
1810         memset(pqp, 0, sizeof(struct bau_pq_entry) * DEST_Q_SIZE);
1811 }
1812 
1813 /*
1814  * Initialization of each UV hub's structures
1815  */
1816 static void __init init_uvhub(int uvhub, int vector, int base_pnode)
1817 {
1818         int node;
1819         int pnode;
1820         unsigned long apicid;
1821 
1822         node = uvhub_to_first_node(uvhub);
1823         pnode = uv_blade_to_pnode(uvhub);
1824 
1825         activation_descriptor_init(node, pnode, base_pnode);
1826 
1827         pq_init(node, pnode);
1828         /*
1829          * The below initialization can't be in firmware because the
1830          * messaging IRQ will be determined by the OS.
1831          */
1832         apicid = uvhub_to_first_apicid(uvhub) | uv_apicid_hibits;
1833         write_mmr_data_config(pnode, ((apicid << 32) | vector));
1834 }
1835 
1836 /*
1837  * We will set BAU_MISC_CONTROL with a timeout period.
1838  * But the BIOS has set UVH_AGING_PRESCALE_SEL and UVH_TRANSACTION_TIMEOUT.
1839  * So the destination timeout period has to be calculated from them.
1840  */
1841 static int calculate_destination_timeout(void)
1842 {
1843         unsigned long mmr_image;
1844         int mult1;
1845         int mult2;
1846         int index;
1847         int base;
1848         int ret;
1849         unsigned long ts_ns;
1850 
1851         if (is_uv1_hub()) {
1852                 mult1 = SOFTACK_TIMEOUT_PERIOD & BAU_MISC_CONTROL_MULT_MASK;
1853                 mmr_image = uv_read_local_mmr(UVH_AGING_PRESCALE_SEL);
1854                 index = (mmr_image >> BAU_URGENCY_7_SHIFT) & BAU_URGENCY_7_MASK;
1855                 mmr_image = uv_read_local_mmr(UVH_TRANSACTION_TIMEOUT);
1856                 mult2 = (mmr_image >> BAU_TRANS_SHIFT) & BAU_TRANS_MASK;
1857                 ts_ns = timeout_base_ns[index];
1858                 ts_ns *= (mult1 * mult2);
1859                 ret = ts_ns / 1000;
1860         } else {
1861                 /* 4 bits  0/1 for 10/80us base, 3 bits of multiplier */
1862                 mmr_image = uv_read_local_mmr(UVH_LB_BAU_MISC_CONTROL);
1863                 mmr_image = (mmr_image & UV_SA_MASK) >> UV_SA_SHFT;
1864                 if (mmr_image & (1L << UV2_ACK_UNITS_SHFT))
1865                         base = 80;
1866                 else
1867                         base = 10;
1868                 mult1 = mmr_image & UV2_ACK_MASK;
1869                 ret = mult1 * base;
1870         }
1871         return ret;
1872 }
1873 
1874 static void __init init_per_cpu_tunables(void)
1875 {
1876         int cpu;
1877         struct bau_control *bcp;
1878 
1879         for_each_present_cpu(cpu) {
1880                 bcp = &per_cpu(bau_control, cpu);
1881                 bcp->baudisabled                = 0;
1882                 if (nobau)
1883                         bcp->nobau              = 1;
1884                 bcp->statp                      = &per_cpu(ptcstats, cpu);
1885                 /* time interval to catch a hardware stay-busy bug */
1886                 bcp->timeout_interval           = usec_2_cycles(2*timeout_us);
1887                 bcp->max_concurr                = max_concurr;
1888                 bcp->max_concurr_const          = max_concurr;
1889                 bcp->plugged_delay              = plugged_delay;
1890                 bcp->plugsb4reset               = plugsb4reset;
1891                 bcp->timeoutsb4reset            = timeoutsb4reset;
1892                 bcp->ipi_reset_limit            = ipi_reset_limit;
1893                 bcp->complete_threshold         = complete_threshold;
1894                 bcp->cong_response_us           = congested_respns_us;
1895                 bcp->cong_reps                  = congested_reps;
1896                 bcp->disabled_period =          sec_2_cycles(disabled_period);
1897                 bcp->giveup_limit =             giveup_limit;
1898                 spin_lock_init(&bcp->queue_lock);
1899                 spin_lock_init(&bcp->uvhub_lock);
1900                 spin_lock_init(&bcp->disable_lock);
1901         }
1902 }
1903 
1904 /*
1905  * Scan all cpus to collect blade and socket summaries.
1906  */
1907 static int __init get_cpu_topology(int base_pnode,
1908                                         struct uvhub_desc *uvhub_descs,
1909                                         unsigned char *uvhub_mask)
1910 {
1911         int cpu;
1912         int pnode;
1913         int uvhub;
1914         int socket;
1915         struct bau_control *bcp;
1916         struct uvhub_desc *bdp;
1917         struct socket_desc *sdp;
1918 
1919         for_each_present_cpu(cpu) {
1920                 bcp = &per_cpu(bau_control, cpu);
1921 
1922                 memset(bcp, 0, sizeof(struct bau_control));
1923 
1924                 pnode = uv_cpu_hub_info(cpu)->pnode;
1925                 if ((pnode - base_pnode) >= UV_DISTRIBUTION_SIZE) {
1926                         printk(KERN_EMERG
1927                                 "cpu %d pnode %d-%d beyond %d; BAU disabled\n",
1928                                 cpu, pnode, base_pnode, UV_DISTRIBUTION_SIZE);
1929                         return 1;
1930                 }
1931 
1932                 bcp->osnode = cpu_to_node(cpu);
1933                 bcp->partition_base_pnode = base_pnode;
1934 
1935                 uvhub = uv_cpu_hub_info(cpu)->numa_blade_id;
1936                 *(uvhub_mask + (uvhub/8)) |= (1 << (uvhub%8));
1937                 bdp = &uvhub_descs[uvhub];
1938 
1939                 bdp->num_cpus++;
1940                 bdp->uvhub = uvhub;
1941                 bdp->pnode = pnode;
1942 
1943                 /* kludge: 'assuming' one node per socket, and assuming that
1944                    disabling a socket just leaves a gap in node numbers */
1945                 socket = bcp->osnode & 1;
1946                 bdp->socket_mask |= (1 << socket);
1947                 sdp = &bdp->socket[socket];
1948                 sdp->cpu_number[sdp->num_cpus] = cpu;
1949                 sdp->num_cpus++;
1950                 if (sdp->num_cpus > MAX_CPUS_PER_SOCKET) {
1951                         printk(KERN_EMERG "%d cpus per socket invalid\n",
1952                                 sdp->num_cpus);
1953                         return 1;
1954                 }
1955         }
1956         return 0;
1957 }
1958 
1959 /*
1960  * Each socket is to get a local array of pnodes/hubs.
1961  */
1962 static void make_per_cpu_thp(struct bau_control *smaster)
1963 {
1964         int cpu;
1965         size_t hpsz = sizeof(struct hub_and_pnode) * num_possible_cpus();
1966 
1967         smaster->thp = kmalloc_node(hpsz, GFP_KERNEL, smaster->osnode);
1968         memset(smaster->thp, 0, hpsz);
1969         for_each_present_cpu(cpu) {
1970                 smaster->thp[cpu].pnode = uv_cpu_hub_info(cpu)->pnode;
1971                 smaster->thp[cpu].uvhub = uv_cpu_hub_info(cpu)->numa_blade_id;
1972         }
1973 }
1974 
1975 /*
1976  * Each uvhub is to get a local cpumask.
1977  */
1978 static void make_per_hub_cpumask(struct bau_control *hmaster)
1979 {
1980         int sz = sizeof(cpumask_t);
1981 
1982         hmaster->cpumask = kzalloc_node(sz, GFP_KERNEL, hmaster->osnode);
1983 }
1984 
1985 /*
1986  * Initialize all the per_cpu information for the cpu's on a given socket,
1987  * given what has been gathered into the socket_desc struct.
1988  * And reports the chosen hub and socket masters back to the caller.
1989  */
1990 static int scan_sock(struct socket_desc *sdp, struct uvhub_desc *bdp,
1991                         struct bau_control **smasterp,
1992                         struct bau_control **hmasterp)
1993 {
1994         int i;
1995         int cpu;
1996         struct bau_control *bcp;
1997 
1998         for (i = 0; i < sdp->num_cpus; i++) {
1999                 cpu = sdp->cpu_number[i];
2000                 bcp = &per_cpu(bau_control, cpu);
2001                 bcp->cpu = cpu;
2002                 if (i == 0) {
2003                         *smasterp = bcp;
2004                         if (!(*hmasterp))
2005                                 *hmasterp = bcp;
2006                 }
2007                 bcp->cpus_in_uvhub = bdp->num_cpus;
2008                 bcp->cpus_in_socket = sdp->num_cpus;
2009                 bcp->socket_master = *smasterp;
2010                 bcp->uvhub = bdp->uvhub;
2011                 if (is_uv1_hub())
2012                         bcp->uvhub_version = 1;
2013                 else if (is_uv2_hub())
2014                         bcp->uvhub_version = 2;
2015                 else {
2016                         printk(KERN_EMERG "uvhub version not 1 or 2\n");
2017                         return 1;
2018                 }
2019                 bcp->uvhub_master = *hmasterp;
2020                 bcp->uvhub_cpu = uv_cpu_hub_info(cpu)->blade_processor_id;
2021                 if (bcp->uvhub_cpu >= MAX_CPUS_PER_UVHUB) {
2022                         printk(KERN_EMERG "%d cpus per uvhub invalid\n",
2023                                 bcp->uvhub_cpu);
2024                         return 1;
2025                 }
2026         }
2027         return 0;
2028 }
2029 
2030 /*
2031  * Summarize the blade and socket topology into the per_cpu structures.
2032  */
2033 static int __init summarize_uvhub_sockets(int nuvhubs,
2034                         struct uvhub_desc *uvhub_descs,
2035                         unsigned char *uvhub_mask)
2036 {
2037         int socket;
2038         int uvhub;
2039         unsigned short socket_mask;
2040 
2041         for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
2042                 struct uvhub_desc *bdp;
2043                 struct bau_control *smaster = NULL;
2044                 struct bau_control *hmaster = NULL;
2045 
2046                 if (!(*(uvhub_mask + (uvhub/8)) & (1 << (uvhub%8))))
2047                         continue;
2048 
2049                 bdp = &uvhub_descs[uvhub];
2050                 socket_mask = bdp->socket_mask;
2051                 socket = 0;
2052                 while (socket_mask) {
2053                         struct socket_desc *sdp;
2054                         if ((socket_mask & 1)) {
2055                                 sdp = &bdp->socket[socket];
2056                                 if (scan_sock(sdp, bdp, &smaster, &hmaster))
2057                                         return 1;
2058                                 make_per_cpu_thp(smaster);
2059                         }
2060                         socket++;
2061                         socket_mask = (socket_mask >> 1);
2062                 }
2063                 make_per_hub_cpumask(hmaster);
2064         }
2065         return 0;
2066 }
2067 
2068 /*
2069  * initialize the bau_control structure for each cpu
2070  */
2071 static int __init init_per_cpu(int nuvhubs, int base_part_pnode)
2072 {
2073         unsigned char *uvhub_mask;
2074         void *vp;
2075         struct uvhub_desc *uvhub_descs;
2076 
2077         timeout_us = calculate_destination_timeout();
2078 
2079         vp = kmalloc(nuvhubs * sizeof(struct uvhub_desc), GFP_KERNEL);
2080         uvhub_descs = (struct uvhub_desc *)vp;
2081         memset(uvhub_descs, 0, nuvhubs * sizeof(struct uvhub_desc));
2082         uvhub_mask = kzalloc((nuvhubs+7)/8, GFP_KERNEL);
2083 
2084         if (get_cpu_topology(base_part_pnode, uvhub_descs, uvhub_mask))
2085                 goto fail;
2086 
2087         if (summarize_uvhub_sockets(nuvhubs, uvhub_descs, uvhub_mask))
2088                 goto fail;
2089 
2090         kfree(uvhub_descs);
2091         kfree(uvhub_mask);
2092         init_per_cpu_tunables();
2093         return 0;
2094 
2095 fail:
2096         kfree(uvhub_descs);
2097         kfree(uvhub_mask);
2098         return 1;
2099 }
2100 
2101 /*
2102  * Initialization of BAU-related structures
2103  */
2104 static int __init uv_bau_init(void)
2105 {
2106         int uvhub;
2107         int pnode;
2108         int nuvhubs;
2109         int cur_cpu;
2110         int cpus;
2111         int vector;
2112         cpumask_var_t *mask;
2113 
2114         if (!is_uv_system())
2115                 return 0;
2116 
2117         for_each_possible_cpu(cur_cpu) {
2118                 mask = &per_cpu(uv_flush_tlb_mask, cur_cpu);
2119                 zalloc_cpumask_var_node(mask, GFP_KERNEL, cpu_to_node(cur_cpu));
2120         }
2121 
2122         nuvhubs = uv_num_possible_blades();
2123         congested_cycles = usec_2_cycles(congested_respns_us);
2124 
2125         uv_base_pnode = 0x7fffffff;
2126         for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
2127                 cpus = uv_blade_nr_possible_cpus(uvhub);
2128                 if (cpus && (uv_blade_to_pnode(uvhub) < uv_base_pnode))
2129                         uv_base_pnode = uv_blade_to_pnode(uvhub);
2130         }
2131 
2132         enable_timeouts();
2133 
2134         if (init_per_cpu(nuvhubs, uv_base_pnode)) {
2135                 set_bau_off();
2136                 nobau_perm = 1;
2137                 return 0;
2138         }
2139 
2140         vector = UV_BAU_MESSAGE;
2141         for_each_possible_blade(uvhub)
2142                 if (uv_blade_nr_possible_cpus(uvhub))
2143                         init_uvhub(uvhub, vector, uv_base_pnode);
2144 
2145         alloc_intr_gate(vector, uv_bau_message_intr1);
2146 
2147         for_each_possible_blade(uvhub) {
2148                 if (uv_blade_nr_possible_cpus(uvhub)) {
2149                         unsigned long val;
2150                         unsigned long mmr;
2151                         pnode = uv_blade_to_pnode(uvhub);
2152                         /* INIT the bau */
2153                         val = 1L << 63;
2154                         write_gmmr_activation(pnode, val);
2155                         mmr = 1; /* should be 1 to broadcast to both sockets */
2156                         if (!is_uv1_hub())
2157                                 write_mmr_data_broadcast(pnode, mmr);
2158                 }
2159         }
2160 
2161         return 0;
2162 }
2163 core_initcall(uv_bau_init);
2164 fs_initcall(uv_ptc_init);
2165 

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