1/*
2 *	SGI UltraViolet TLB flush routines.
3 *
4 *	(c) 2008-2014 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) */
28static int timeout_base_ns[] = {
29		20,
30		160,
31		1280,
32		10240,
33		81920,
34		655360,
35		5242880,
36		167772160
37};
38
39static int timeout_us;
40static int nobau;
41static int nobau_perm;
42static cycles_t congested_cycles;
43
44/* tunables: */
45static int max_concurr		= MAX_BAU_CONCURRENT;
46static int max_concurr_const	= MAX_BAU_CONCURRENT;
47static int plugged_delay	= PLUGGED_DELAY;
48static int plugsb4reset		= PLUGSB4RESET;
49static int giveup_limit		= GIVEUP_LIMIT;
50static int timeoutsb4reset	= TIMEOUTSB4RESET;
51static int ipi_reset_limit	= IPI_RESET_LIMIT;
52static int complete_threshold	= COMPLETE_THRESHOLD;
53static int congested_respns_us	= CONGESTED_RESPONSE_US;
54static int congested_reps	= CONGESTED_REPS;
55static int disabled_period	= DISABLED_PERIOD;
56
57static 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
70static struct dentry *tunables_dir;
71static struct dentry *tunables_file;
72
73/* these correspond to the statistics printed by ptc_seq_show() */
74static 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
109static int __init
110setup_nobau(char *arg)
111{
112	nobau = 1;
113	return 0;
114}
115early_param("nobau", setup_nobau);
116
117/* base pnode in this partition */
118static int uv_base_pnode __read_mostly;
119
120static DEFINE_PER_CPU(struct ptc_stats, ptcstats);
121static DEFINE_PER_CPU(struct bau_control, bau_control);
122static DEFINE_PER_CPU(cpumask_var_t, uv_flush_tlb_mask);
123
124static void
125set_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
143static void
144set_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 */
162static 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 */
177static 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 */
195static 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 */
213static 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 */
270static 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 */
335static 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 */
358static 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 */
407static 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 */
441static 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 */
455static 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
466static inline unsigned long cycles_2_us(unsigned long long cyc)
467{
468	return cycles_2_ns(cyc) / NSEC_PER_USEC;
469}
470
471static inline cycles_t sec_2_cycles(unsigned long sec)
472{
473	return ns_2_cycles(sec * NSEC_PER_SEC);
474}
475
476static 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 */
486static 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 */
494static inline void end_uvhub_quiesce(struct bau_control *hmaster)
495{
496	atom_asr(-1, (struct atomic_short *)&hmaster->uvhub_quiesce);
497}
498
499static 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 */
513static 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 */
566static unsigned long uv2_3_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 */
583int 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 */
600int 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
609static int uv2_3_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_3_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) > bcp->timeout_interval)
662					return handle_uv2_busy(bcp);
663			}
664			/*
665			 * descriptor_stat is still BUSY
666			 */
667			cpu_relax();
668		}
669		descriptor_stat = uv2_3_read_status(mmr_offset, right_shift, desc);
670	}
671	bcp->conseccompletes++;
672	return FLUSH_COMPLETE;
673}
674
675/*
676 * There are 2 status registers; each and array[32] of 2 bits. Set up for
677 * which register to read and position in that register based on cpu in
678 * current hub.
679 */
680static int wait_completion(struct bau_desc *bau_desc, struct bau_control *bcp, long try)
681{
682	int right_shift;
683	unsigned long mmr_offset;
684	int desc = bcp->uvhub_cpu;
685
686	if (desc < UV_CPUS_PER_AS) {
687		mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_0;
688		right_shift = desc * UV_ACT_STATUS_SIZE;
689	} else {
690		mmr_offset = UVH_LB_BAU_SB_ACTIVATION_STATUS_1;
691		right_shift = ((desc - UV_CPUS_PER_AS) * UV_ACT_STATUS_SIZE);
692	}
693
694	if (bcp->uvhub_version == 1)
695		return uv1_wait_completion(bau_desc, mmr_offset, right_shift, bcp, try);
696	else
697		return uv2_3_wait_completion(bau_desc, mmr_offset, right_shift, bcp, try);
698}
699
700/*
701 * Our retries are blocked by all destination sw ack resources being
702 * in use, and a timeout is pending. In that case hardware immediately
703 * returns the ERROR that looks like a destination timeout.
704 */
705static void destination_plugged(struct bau_desc *bau_desc,
706			struct bau_control *bcp,
707			struct bau_control *hmaster, struct ptc_stats *stat)
708{
709	udelay(bcp->plugged_delay);
710	bcp->plugged_tries++;
711
712	if (bcp->plugged_tries >= bcp->plugsb4reset) {
713		bcp->plugged_tries = 0;
714
715		quiesce_local_uvhub(hmaster);
716
717		spin_lock(&hmaster->queue_lock);
718		reset_with_ipi(&bau_desc->distribution, bcp);
719		spin_unlock(&hmaster->queue_lock);
720
721		end_uvhub_quiesce(hmaster);
722
723		bcp->ipi_attempts++;
724		stat->s_resets_plug++;
725	}
726}
727
728static void destination_timeout(struct bau_desc *bau_desc,
729			struct bau_control *bcp, struct bau_control *hmaster,
730			struct ptc_stats *stat)
731{
732	hmaster->max_concurr = 1;
733	bcp->timeout_tries++;
734	if (bcp->timeout_tries >= bcp->timeoutsb4reset) {
735		bcp->timeout_tries = 0;
736
737		quiesce_local_uvhub(hmaster);
738
739		spin_lock(&hmaster->queue_lock);
740		reset_with_ipi(&bau_desc->distribution, bcp);
741		spin_unlock(&hmaster->queue_lock);
742
743		end_uvhub_quiesce(hmaster);
744
745		bcp->ipi_attempts++;
746		stat->s_resets_timeout++;
747	}
748}
749
750/*
751 * Stop all cpus on a uvhub from using the BAU for a period of time.
752 * This is reversed by check_enable.
753 */
754static void disable_for_period(struct bau_control *bcp, struct ptc_stats *stat)
755{
756	int tcpu;
757	struct bau_control *tbcp;
758	struct bau_control *hmaster;
759	cycles_t tm1;
760
761	hmaster = bcp->uvhub_master;
762	spin_lock(&hmaster->disable_lock);
763	if (!bcp->baudisabled) {
764		stat->s_bau_disabled++;
765		tm1 = get_cycles();
766		for_each_present_cpu(tcpu) {
767			tbcp = &per_cpu(bau_control, tcpu);
768			if (tbcp->uvhub_master == hmaster) {
769				tbcp->baudisabled = 1;
770				tbcp->set_bau_on_time =
771					tm1 + bcp->disabled_period;
772			}
773		}
774	}
775	spin_unlock(&hmaster->disable_lock);
776}
777
778static void count_max_concurr(int stat, struct bau_control *bcp,
779				struct bau_control *hmaster)
780{
781	bcp->plugged_tries = 0;
782	bcp->timeout_tries = 0;
783	if (stat != FLUSH_COMPLETE)
784		return;
785	if (bcp->conseccompletes <= bcp->complete_threshold)
786		return;
787	if (hmaster->max_concurr >= hmaster->max_concurr_const)
788		return;
789	hmaster->max_concurr++;
790}
791
792static void record_send_stats(cycles_t time1, cycles_t time2,
793		struct bau_control *bcp, struct ptc_stats *stat,
794		int completion_status, int try)
795{
796	cycles_t elapsed;
797
798	if (time2 > time1) {
799		elapsed = time2 - time1;
800		stat->s_time += elapsed;
801
802		if ((completion_status == FLUSH_COMPLETE) && (try == 1)) {
803			bcp->period_requests++;
804			bcp->period_time += elapsed;
805			if ((elapsed > congested_cycles) &&
806			    (bcp->period_requests > bcp->cong_reps) &&
807			    ((bcp->period_time / bcp->period_requests) >
808							congested_cycles)) {
809				stat->s_congested++;
810				disable_for_period(bcp, stat);
811			}
812		}
813	} else
814		stat->s_requestor--;
815
816	if (completion_status == FLUSH_COMPLETE && try > 1)
817		stat->s_retriesok++;
818	else if (completion_status == FLUSH_GIVEUP) {
819		stat->s_giveup++;
820		if (get_cycles() > bcp->period_end)
821			bcp->period_giveups = 0;
822		bcp->period_giveups++;
823		if (bcp->period_giveups == 1)
824			bcp->period_end = get_cycles() + bcp->disabled_period;
825		if (bcp->period_giveups > bcp->giveup_limit) {
826			disable_for_period(bcp, stat);
827			stat->s_giveuplimit++;
828		}
829	}
830}
831
832/*
833 * Because of a uv1 hardware bug only a limited number of concurrent
834 * requests can be made.
835 */
836static void uv1_throttle(struct bau_control *hmaster, struct ptc_stats *stat)
837{
838	spinlock_t *lock = &hmaster->uvhub_lock;
839	atomic_t *v;
840
841	v = &hmaster->active_descriptor_count;
842	if (!atomic_inc_unless_ge(lock, v, hmaster->max_concurr)) {
843		stat->s_throttles++;
844		do {
845			cpu_relax();
846		} while (!atomic_inc_unless_ge(lock, v, hmaster->max_concurr));
847	}
848}
849
850/*
851 * Handle the completion status of a message send.
852 */
853static void handle_cmplt(int completion_status, struct bau_desc *bau_desc,
854			struct bau_control *bcp, struct bau_control *hmaster,
855			struct ptc_stats *stat)
856{
857	if (completion_status == FLUSH_RETRY_PLUGGED)
858		destination_plugged(bau_desc, bcp, hmaster, stat);
859	else if (completion_status == FLUSH_RETRY_TIMEOUT)
860		destination_timeout(bau_desc, bcp, hmaster, stat);
861}
862
863/*
864 * Send a broadcast and wait for it to complete.
865 *
866 * The flush_mask contains the cpus the broadcast is to be sent to including
867 * cpus that are on the local uvhub.
868 *
869 * Returns 0 if all flushing represented in the mask was done.
870 * Returns 1 if it gives up entirely and the original cpu mask is to be
871 * returned to the kernel.
872 */
873int uv_flush_send_and_wait(struct cpumask *flush_mask, struct bau_control *bcp,
874	struct bau_desc *bau_desc)
875{
876	int seq_number = 0;
877	int completion_stat = 0;
878	int uv1 = 0;
879	long try = 0;
880	unsigned long index;
881	cycles_t time1;
882	cycles_t time2;
883	struct ptc_stats *stat = bcp->statp;
884	struct bau_control *hmaster = bcp->uvhub_master;
885	struct uv1_bau_msg_header *uv1_hdr = NULL;
886	struct uv2_3_bau_msg_header *uv2_3_hdr = NULL;
887
888	if (bcp->uvhub_version == 1) {
889		uv1 = 1;
890		uv1_throttle(hmaster, stat);
891	}
892
893	while (hmaster->uvhub_quiesce)
894		cpu_relax();
895
896	time1 = get_cycles();
897	if (uv1)
898		uv1_hdr = &bau_desc->header.uv1_hdr;
899	else
900		/* uv2 and uv3 */
901		uv2_3_hdr = &bau_desc->header.uv2_3_hdr;
902
903	do {
904		if (try == 0) {
905			if (uv1)
906				uv1_hdr->msg_type = MSG_REGULAR;
907			else
908				uv2_3_hdr->msg_type = MSG_REGULAR;
909			seq_number = bcp->message_number++;
910		} else {
911			if (uv1)
912				uv1_hdr->msg_type = MSG_RETRY;
913			else
914				uv2_3_hdr->msg_type = MSG_RETRY;
915			stat->s_retry_messages++;
916		}
917
918		if (uv1)
919			uv1_hdr->sequence = seq_number;
920		else
921			uv2_3_hdr->sequence = seq_number;
922		index = (1UL << AS_PUSH_SHIFT) | bcp->uvhub_cpu;
923		bcp->send_message = get_cycles();
924
925		write_mmr_activation(index);
926
927		try++;
928		completion_stat = wait_completion(bau_desc, bcp, try);
929
930		handle_cmplt(completion_stat, bau_desc, bcp, hmaster, stat);
931
932		if (bcp->ipi_attempts >= bcp->ipi_reset_limit) {
933			bcp->ipi_attempts = 0;
934			stat->s_overipilimit++;
935			completion_stat = FLUSH_GIVEUP;
936			break;
937		}
938		cpu_relax();
939	} while ((completion_stat == FLUSH_RETRY_PLUGGED) ||
940		 (completion_stat == FLUSH_RETRY_TIMEOUT));
941
942	time2 = get_cycles();
943
944	count_max_concurr(completion_stat, bcp, hmaster);
945
946	while (hmaster->uvhub_quiesce)
947		cpu_relax();
948
949	atomic_dec(&hmaster->active_descriptor_count);
950
951	record_send_stats(time1, time2, bcp, stat, completion_stat, try);
952
953	if (completion_stat == FLUSH_GIVEUP)
954		/* FLUSH_GIVEUP will fall back to using IPI's for tlb flush */
955		return 1;
956	return 0;
957}
958
959/*
960 * The BAU is disabled for this uvhub. When the disabled time period has
961 * expired re-enable it.
962 * Return 0 if it is re-enabled for all cpus on this uvhub.
963 */
964static int check_enable(struct bau_control *bcp, struct ptc_stats *stat)
965{
966	int tcpu;
967	struct bau_control *tbcp;
968	struct bau_control *hmaster;
969
970	hmaster = bcp->uvhub_master;
971	spin_lock(&hmaster->disable_lock);
972	if (bcp->baudisabled && (get_cycles() >= bcp->set_bau_on_time)) {
973		stat->s_bau_reenabled++;
974		for_each_present_cpu(tcpu) {
975			tbcp = &per_cpu(bau_control, tcpu);
976			if (tbcp->uvhub_master == hmaster) {
977				tbcp->baudisabled = 0;
978				tbcp->period_requests = 0;
979				tbcp->period_time = 0;
980				tbcp->period_giveups = 0;
981			}
982		}
983		spin_unlock(&hmaster->disable_lock);
984		return 0;
985	}
986	spin_unlock(&hmaster->disable_lock);
987	return -1;
988}
989
990static void record_send_statistics(struct ptc_stats *stat, int locals, int hubs,
991				int remotes, struct bau_desc *bau_desc)
992{
993	stat->s_requestor++;
994	stat->s_ntargcpu += remotes + locals;
995	stat->s_ntargremotes += remotes;
996	stat->s_ntarglocals += locals;
997
998	/* uvhub statistics */
999	hubs = bau_uvhub_weight(&bau_desc->distribution);
1000	if (locals) {
1001		stat->s_ntarglocaluvhub++;
1002		stat->s_ntargremoteuvhub += (hubs - 1);
1003	} else
1004		stat->s_ntargremoteuvhub += hubs;
1005
1006	stat->s_ntarguvhub += hubs;
1007
1008	if (hubs >= 16)
1009		stat->s_ntarguvhub16++;
1010	else if (hubs >= 8)
1011		stat->s_ntarguvhub8++;
1012	else if (hubs >= 4)
1013		stat->s_ntarguvhub4++;
1014	else if (hubs >= 2)
1015		stat->s_ntarguvhub2++;
1016	else
1017		stat->s_ntarguvhub1++;
1018}
1019
1020/*
1021 * Translate a cpu mask to the uvhub distribution mask in the BAU
1022 * activation descriptor.
1023 */
1024static int set_distrib_bits(struct cpumask *flush_mask, struct bau_control *bcp,
1025			struct bau_desc *bau_desc, int *localsp, int *remotesp)
1026{
1027	int cpu;
1028	int pnode;
1029	int cnt = 0;
1030	struct hub_and_pnode *hpp;
1031
1032	for_each_cpu(cpu, flush_mask) {
1033		/*
1034		 * The distribution vector is a bit map of pnodes, relative
1035		 * to the partition base pnode (and the partition base nasid
1036		 * in the header).
1037		 * Translate cpu to pnode and hub using a local memory array.
1038		 */
1039		hpp = &bcp->socket_master->thp[cpu];
1040		pnode = hpp->pnode - bcp->partition_base_pnode;
1041		bau_uvhub_set(pnode, &bau_desc->distribution);
1042		cnt++;
1043		if (hpp->uvhub == bcp->uvhub)
1044			(*localsp)++;
1045		else
1046			(*remotesp)++;
1047	}
1048	if (!cnt)
1049		return 1;
1050	return 0;
1051}
1052
1053/*
1054 * globally purge translation cache of a virtual address or all TLB's
1055 * @cpumask: mask of all cpu's in which the address is to be removed
1056 * @mm: mm_struct containing virtual address range
1057 * @start: start virtual address to be removed from TLB
1058 * @end: end virtual address to be remove from TLB
1059 * @cpu: the current cpu
1060 *
1061 * This is the entry point for initiating any UV global TLB shootdown.
1062 *
1063 * Purges the translation caches of all specified processors of the given
1064 * virtual address, or purges all TLB's on specified processors.
1065 *
1066 * The caller has derived the cpumask from the mm_struct.  This function
1067 * is called only if there are bits set in the mask. (e.g. flush_tlb_page())
1068 *
1069 * The cpumask is converted into a uvhubmask of the uvhubs containing
1070 * those cpus.
1071 *
1072 * Note that this function should be called with preemption disabled.
1073 *
1074 * Returns NULL if all remote flushing was done.
1075 * Returns pointer to cpumask if some remote flushing remains to be
1076 * done.  The returned pointer is valid till preemption is re-enabled.
1077 */
1078const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
1079						struct mm_struct *mm,
1080						unsigned long start,
1081						unsigned long end,
1082						unsigned int cpu)
1083{
1084	int locals = 0;
1085	int remotes = 0;
1086	int hubs = 0;
1087	struct bau_desc *bau_desc;
1088	struct cpumask *flush_mask;
1089	struct ptc_stats *stat;
1090	struct bau_control *bcp;
1091	unsigned long descriptor_status;
1092	unsigned long status;
1093
1094	bcp = &per_cpu(bau_control, cpu);
1095
1096	if (bcp->nobau)
1097		return cpumask;
1098
1099	stat = bcp->statp;
1100	stat->s_enters++;
1101
1102	if (bcp->busy) {
1103		descriptor_status =
1104			read_lmmr(UVH_LB_BAU_SB_ACTIVATION_STATUS_0);
1105		status = ((descriptor_status >> (bcp->uvhub_cpu *
1106			UV_ACT_STATUS_SIZE)) & UV_ACT_STATUS_MASK) << 1;
1107		if (status == UV2H_DESC_BUSY)
1108			return cpumask;
1109		bcp->busy = 0;
1110	}
1111
1112	/* bau was disabled due to slow response */
1113	if (bcp->baudisabled) {
1114		if (check_enable(bcp, stat)) {
1115			stat->s_ipifordisabled++;
1116			return cpumask;
1117		}
1118	}
1119
1120	/*
1121	 * Each sending cpu has a per-cpu mask which it fills from the caller's
1122	 * cpu mask.  All cpus are converted to uvhubs and copied to the
1123	 * activation descriptor.
1124	 */
1125	flush_mask = (struct cpumask *)per_cpu(uv_flush_tlb_mask, cpu);
1126	/* don't actually do a shootdown of the local cpu */
1127	cpumask_andnot(flush_mask, cpumask, cpumask_of(cpu));
1128
1129	if (cpu_isset(cpu, *cpumask))
1130		stat->s_ntargself++;
1131
1132	bau_desc = bcp->descriptor_base;
1133	bau_desc += (ITEMS_PER_DESC * bcp->uvhub_cpu);
1134	bau_uvhubs_clear(&bau_desc->distribution, UV_DISTRIBUTION_SIZE);
1135	if (set_distrib_bits(flush_mask, bcp, bau_desc, &locals, &remotes))
1136		return NULL;
1137
1138	record_send_statistics(stat, locals, hubs, remotes, bau_desc);
1139
1140	if (!end || (end - start) <= PAGE_SIZE)
1141		bau_desc->payload.address = start;
1142	else
1143		bau_desc->payload.address = TLB_FLUSH_ALL;
1144	bau_desc->payload.sending_cpu = cpu;
1145	/*
1146	 * uv_flush_send_and_wait returns 0 if all cpu's were messaged,
1147	 * or 1 if it gave up and the original cpumask should be returned.
1148	 */
1149	if (!uv_flush_send_and_wait(flush_mask, bcp, bau_desc))
1150		return NULL;
1151	else
1152		return cpumask;
1153}
1154
1155/*
1156 * Search the message queue for any 'other' unprocessed message with the
1157 * same software acknowledge resource bit vector as the 'msg' message.
1158 */
1159struct bau_pq_entry *find_another_by_swack(struct bau_pq_entry *msg,
1160					   struct bau_control *bcp)
1161{
1162	struct bau_pq_entry *msg_next = msg + 1;
1163	unsigned char swack_vec = msg->swack_vec;
1164
1165	if (msg_next > bcp->queue_last)
1166		msg_next = bcp->queue_first;
1167	while (msg_next != msg) {
1168		if ((msg_next->canceled == 0) && (msg_next->replied_to == 0) &&
1169				(msg_next->swack_vec == swack_vec))
1170			return msg_next;
1171		msg_next++;
1172		if (msg_next > bcp->queue_last)
1173			msg_next = bcp->queue_first;
1174	}
1175	return NULL;
1176}
1177
1178/*
1179 * UV2 needs to work around a bug in which an arriving message has not
1180 * set a bit in the UVH_LB_BAU_INTD_SOFTWARE_ACKNOWLEDGE register.
1181 * Such a message must be ignored.
1182 */
1183void process_uv2_message(struct msg_desc *mdp, struct bau_control *bcp)
1184{
1185	unsigned long mmr_image;
1186	unsigned char swack_vec;
1187	struct bau_pq_entry *msg = mdp->msg;
1188	struct bau_pq_entry *other_msg;
1189
1190	mmr_image = read_mmr_sw_ack();
1191	swack_vec = msg->swack_vec;
1192
1193	if ((swack_vec & mmr_image) == 0) {
1194		/*
1195		 * This message was assigned a swack resource, but no
1196		 * reserved acknowlegment is pending.
1197		 * The bug has prevented this message from setting the MMR.
1198		 */
1199		/*
1200		 * Some message has set the MMR 'pending' bit; it might have
1201		 * been another message.  Look for that message.
1202		 */
1203		other_msg = find_another_by_swack(msg, bcp);
1204		if (other_msg) {
1205			/*
1206			 * There is another. Process this one but do not
1207			 * ack it.
1208			 */
1209			bau_process_message(mdp, bcp, 0);
1210			/*
1211			 * Let the natural processing of that other message
1212			 * acknowledge it. Don't get the processing of sw_ack's
1213			 * out of order.
1214			 */
1215			return;
1216		}
1217	}
1218
1219	/*
1220	 * Either the MMR shows this one pending a reply or there is no
1221	 * other message using this sw_ack, so it is safe to acknowledge it.
1222	 */
1223	bau_process_message(mdp, bcp, 1);
1224
1225	return;
1226}
1227
1228/*
1229 * The BAU message interrupt comes here. (registered by set_intr_gate)
1230 * See entry_64.S
1231 *
1232 * We received a broadcast assist message.
1233 *
1234 * Interrupts are disabled; this interrupt could represent
1235 * the receipt of several messages.
1236 *
1237 * All cores/threads on this hub get this interrupt.
1238 * The last one to see it does the software ack.
1239 * (the resource will not be freed until noninterruptable cpus see this
1240 *  interrupt; hardware may timeout the s/w ack and reply ERROR)
1241 */
1242void uv_bau_message_interrupt(struct pt_regs *regs)
1243{
1244	int count = 0;
1245	cycles_t time_start;
1246	struct bau_pq_entry *msg;
1247	struct bau_control *bcp;
1248	struct ptc_stats *stat;
1249	struct msg_desc msgdesc;
1250
1251	ack_APIC_irq();
1252	time_start = get_cycles();
1253
1254	bcp = &per_cpu(bau_control, smp_processor_id());
1255	stat = bcp->statp;
1256
1257	msgdesc.queue_first = bcp->queue_first;
1258	msgdesc.queue_last = bcp->queue_last;
1259
1260	msg = bcp->bau_msg_head;
1261	while (msg->swack_vec) {
1262		count++;
1263
1264		msgdesc.msg_slot = msg - msgdesc.queue_first;
1265		msgdesc.msg = msg;
1266		if (bcp->uvhub_version == 2)
1267			process_uv2_message(&msgdesc, bcp);
1268		else
1269			/* no error workaround for uv1 or uv3 */
1270			bau_process_message(&msgdesc, bcp, 1);
1271
1272		msg++;
1273		if (msg > msgdesc.queue_last)
1274			msg = msgdesc.queue_first;
1275		bcp->bau_msg_head = msg;
1276	}
1277	stat->d_time += (get_cycles() - time_start);
1278	if (!count)
1279		stat->d_nomsg++;
1280	else if (count > 1)
1281		stat->d_multmsg++;
1282}
1283
1284/*
1285 * Each target uvhub (i.e. a uvhub that has cpu's) needs to have
1286 * shootdown message timeouts enabled.  The timeout does not cause
1287 * an interrupt, but causes an error message to be returned to
1288 * the sender.
1289 */
1290static void __init enable_timeouts(void)
1291{
1292	int uvhub;
1293	int nuvhubs;
1294	int pnode;
1295	unsigned long mmr_image;
1296
1297	nuvhubs = uv_num_possible_blades();
1298
1299	for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
1300		if (!uv_blade_nr_possible_cpus(uvhub))
1301			continue;
1302
1303		pnode = uv_blade_to_pnode(uvhub);
1304		mmr_image = read_mmr_misc_control(pnode);
1305		/*
1306		 * Set the timeout period and then lock it in, in three
1307		 * steps; captures and locks in the period.
1308		 *
1309		 * To program the period, the SOFT_ACK_MODE must be off.
1310		 */
1311		mmr_image &= ~(1L << SOFTACK_MSHIFT);
1312		write_mmr_misc_control(pnode, mmr_image);
1313		/*
1314		 * Set the 4-bit period.
1315		 */
1316		mmr_image &= ~((unsigned long)0xf << SOFTACK_PSHIFT);
1317		mmr_image |= (SOFTACK_TIMEOUT_PERIOD << SOFTACK_PSHIFT);
1318		write_mmr_misc_control(pnode, mmr_image);
1319		/*
1320		 * UV1:
1321		 * Subsequent reversals of the timebase bit (3) cause an
1322		 * immediate timeout of one or all INTD resources as
1323		 * indicated in bits 2:0 (7 causes all of them to timeout).
1324		 */
1325		mmr_image |= (1L << SOFTACK_MSHIFT);
1326		if (is_uv2_hub()) {
1327			/* do not touch the legacy mode bit */
1328			/* hw bug workaround; do not use extended status */
1329			mmr_image &= ~(1L << UV2_EXT_SHFT);
1330		} else if (is_uv3_hub()) {
1331			mmr_image &= ~(1L << PREFETCH_HINT_SHFT);
1332			mmr_image |= (1L << SB_STATUS_SHFT);
1333		}
1334		write_mmr_misc_control(pnode, mmr_image);
1335	}
1336}
1337
1338static void *ptc_seq_start(struct seq_file *file, loff_t *offset)
1339{
1340	if (*offset < num_possible_cpus())
1341		return offset;
1342	return NULL;
1343}
1344
1345static void *ptc_seq_next(struct seq_file *file, void *data, loff_t *offset)
1346{
1347	(*offset)++;
1348	if (*offset < num_possible_cpus())
1349		return offset;
1350	return NULL;
1351}
1352
1353static void ptc_seq_stop(struct seq_file *file, void *data)
1354{
1355}
1356
1357/*
1358 * Display the statistics thru /proc/sgi_uv/ptc_statistics
1359 * 'data' points to the cpu number
1360 * Note: see the descriptions in stat_description[].
1361 */
1362static int ptc_seq_show(struct seq_file *file, void *data)
1363{
1364	struct ptc_stats *stat;
1365	struct bau_control *bcp;
1366	int cpu;
1367
1368	cpu = *(loff_t *)data;
1369	if (!cpu) {
1370		seq_printf(file,
1371		 "# cpu bauoff sent stime self locals remotes ncpus localhub ");
1372		seq_printf(file,
1373			"remotehub numuvhubs numuvhubs16 numuvhubs8 ");
1374		seq_printf(file,
1375			"numuvhubs4 numuvhubs2 numuvhubs1 dto snacks retries ");
1376		seq_printf(file,
1377			"rok resetp resett giveup sto bz throt disable ");
1378		seq_printf(file,
1379			"enable wars warshw warwaits enters ipidis plugged ");
1380		seq_printf(file,
1381			"ipiover glim cong swack recv rtime all one mult ");
1382		seq_printf(file,
1383			"none retry canc nocan reset rcan\n");
1384	}
1385	if (cpu < num_possible_cpus() && cpu_online(cpu)) {
1386		bcp = &per_cpu(bau_control, cpu);
1387		stat = bcp->statp;
1388		/* source side statistics */
1389		seq_printf(file,
1390			"cpu %d %d %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
1391			   cpu, bcp->nobau, stat->s_requestor,
1392			   cycles_2_us(stat->s_time),
1393			   stat->s_ntargself, stat->s_ntarglocals,
1394			   stat->s_ntargremotes, stat->s_ntargcpu,
1395			   stat->s_ntarglocaluvhub, stat->s_ntargremoteuvhub,
1396			   stat->s_ntarguvhub, stat->s_ntarguvhub16);
1397		seq_printf(file, "%ld %ld %ld %ld %ld %ld ",
1398			   stat->s_ntarguvhub8, stat->s_ntarguvhub4,
1399			   stat->s_ntarguvhub2, stat->s_ntarguvhub1,
1400			   stat->s_dtimeout, stat->s_strongnacks);
1401		seq_printf(file, "%ld %ld %ld %ld %ld %ld %ld %ld ",
1402			   stat->s_retry_messages, stat->s_retriesok,
1403			   stat->s_resets_plug, stat->s_resets_timeout,
1404			   stat->s_giveup, stat->s_stimeout,
1405			   stat->s_busy, stat->s_throttles);
1406		seq_printf(file, "%ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld ",
1407			   stat->s_bau_disabled, stat->s_bau_reenabled,
1408			   stat->s_uv2_wars, stat->s_uv2_wars_hw,
1409			   stat->s_uv2_war_waits, stat->s_enters,
1410			   stat->s_ipifordisabled, stat->s_plugged,
1411			   stat->s_overipilimit, stat->s_giveuplimit,
1412			   stat->s_congested);
1413
1414		/* destination side statistics */
1415		seq_printf(file,
1416			"%lx %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld\n",
1417			   read_gmmr_sw_ack(uv_cpu_to_pnode(cpu)),
1418			   stat->d_requestee, cycles_2_us(stat->d_time),
1419			   stat->d_alltlb, stat->d_onetlb, stat->d_multmsg,
1420			   stat->d_nomsg, stat->d_retries, stat->d_canceled,
1421			   stat->d_nocanceled, stat->d_resets,
1422			   stat->d_rcanceled);
1423	}
1424	return 0;
1425}
1426
1427/*
1428 * Display the tunables thru debugfs
1429 */
1430static ssize_t tunables_read(struct file *file, char __user *userbuf,
1431				size_t count, loff_t *ppos)
1432{
1433	char *buf;
1434	int ret;
1435
1436	buf = kasprintf(GFP_KERNEL, "%s %s %s\n%d %d %d %d %d %d %d %d %d %d\n",
1437		"max_concur plugged_delay plugsb4reset timeoutsb4reset",
1438		"ipi_reset_limit complete_threshold congested_response_us",
1439		"congested_reps disabled_period giveup_limit",
1440		max_concurr, plugged_delay, plugsb4reset,
1441		timeoutsb4reset, ipi_reset_limit, complete_threshold,
1442		congested_respns_us, congested_reps, disabled_period,
1443		giveup_limit);
1444
1445	if (!buf)
1446		return -ENOMEM;
1447
1448	ret = simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
1449	kfree(buf);
1450	return ret;
1451}
1452
1453/*
1454 * handle a write to /proc/sgi_uv/ptc_statistics
1455 * -1: reset the statistics
1456 *  0: display meaning of the statistics
1457 */
1458static ssize_t ptc_proc_write(struct file *file, const char __user *user,
1459				size_t count, loff_t *data)
1460{
1461	int cpu;
1462	int i;
1463	int elements;
1464	long input_arg;
1465	char optstr[64];
1466	struct ptc_stats *stat;
1467
1468	if (count == 0 || count > sizeof(optstr))
1469		return -EINVAL;
1470	if (copy_from_user(optstr, user, count))
1471		return -EFAULT;
1472	optstr[count - 1] = '\0';
1473
1474	if (!strcmp(optstr, "on")) {
1475		set_bau_on();
1476		return count;
1477	} else if (!strcmp(optstr, "off")) {
1478		set_bau_off();
1479		return count;
1480	}
1481
1482	if (kstrtol(optstr, 10, &input_arg) < 0) {
1483		printk(KERN_DEBUG "%s is invalid\n", optstr);
1484		return -EINVAL;
1485	}
1486
1487	if (input_arg == 0) {
1488		elements = ARRAY_SIZE(stat_description);
1489		printk(KERN_DEBUG "# cpu:      cpu number\n");
1490		printk(KERN_DEBUG "Sender statistics:\n");
1491		for (i = 0; i < elements; i++)
1492			printk(KERN_DEBUG "%s\n", stat_description[i]);
1493	} else if (input_arg == -1) {
1494		for_each_present_cpu(cpu) {
1495			stat = &per_cpu(ptcstats, cpu);
1496			memset(stat, 0, sizeof(struct ptc_stats));
1497		}
1498	}
1499
1500	return count;
1501}
1502
1503static int local_atoi(const char *name)
1504{
1505	int val = 0;
1506
1507	for (;; name++) {
1508		switch (*name) {
1509		case '0' ... '9':
1510			val = 10*val+(*name-'0');
1511			break;
1512		default:
1513			return val;
1514		}
1515	}
1516}
1517
1518/*
1519 * Parse the values written to /sys/kernel/debug/sgi_uv/bau_tunables.
1520 * Zero values reset them to defaults.
1521 */
1522static int parse_tunables_write(struct bau_control *bcp, char *instr,
1523				int count)
1524{
1525	char *p;
1526	char *q;
1527	int cnt = 0;
1528	int val;
1529	int e = ARRAY_SIZE(tunables);
1530
1531	p = instr + strspn(instr, WHITESPACE);
1532	q = p;
1533	for (; *p; p = q + strspn(q, WHITESPACE)) {
1534		q = p + strcspn(p, WHITESPACE);
1535		cnt++;
1536		if (q == p)
1537			break;
1538	}
1539	if (cnt != e) {
1540		printk(KERN_INFO "bau tunable error: should be %d values\n", e);
1541		return -EINVAL;
1542	}
1543
1544	p = instr + strspn(instr, WHITESPACE);
1545	q = p;
1546	for (cnt = 0; *p; p = q + strspn(q, WHITESPACE), cnt++) {
1547		q = p + strcspn(p, WHITESPACE);
1548		val = local_atoi(p);
1549		switch (cnt) {
1550		case 0:
1551			if (val == 0) {
1552				max_concurr = MAX_BAU_CONCURRENT;
1553				max_concurr_const = MAX_BAU_CONCURRENT;
1554				continue;
1555			}
1556			if (val < 1 || val > bcp->cpus_in_uvhub) {
1557				printk(KERN_DEBUG
1558				"Error: BAU max concurrent %d is invalid\n",
1559				val);
1560				return -EINVAL;
1561			}
1562			max_concurr = val;
1563			max_concurr_const = val;
1564			continue;
1565		default:
1566			if (val == 0)
1567				*tunables[cnt].tunp = tunables[cnt].deflt;
1568			else
1569				*tunables[cnt].tunp = val;
1570			continue;
1571		}
1572		if (q == p)
1573			break;
1574	}
1575	return 0;
1576}
1577
1578/*
1579 * Handle a write to debugfs. (/sys/kernel/debug/sgi_uv/bau_tunables)
1580 */
1581static ssize_t tunables_write(struct file *file, const char __user *user,
1582				size_t count, loff_t *data)
1583{
1584	int cpu;
1585	int ret;
1586	char instr[100];
1587	struct bau_control *bcp;
1588
1589	if (count == 0 || count > sizeof(instr)-1)
1590		return -EINVAL;
1591	if (copy_from_user(instr, user, count))
1592		return -EFAULT;
1593
1594	instr[count] = '\0';
1595
1596	cpu = get_cpu();
1597	bcp = &per_cpu(bau_control, cpu);
1598	ret = parse_tunables_write(bcp, instr, count);
1599	put_cpu();
1600	if (ret)
1601		return ret;
1602
1603	for_each_present_cpu(cpu) {
1604		bcp = &per_cpu(bau_control, cpu);
1605		bcp->max_concurr =		max_concurr;
1606		bcp->max_concurr_const =	max_concurr;
1607		bcp->plugged_delay =		plugged_delay;
1608		bcp->plugsb4reset =		plugsb4reset;
1609		bcp->timeoutsb4reset =		timeoutsb4reset;
1610		bcp->ipi_reset_limit =		ipi_reset_limit;
1611		bcp->complete_threshold =	complete_threshold;
1612		bcp->cong_response_us =		congested_respns_us;
1613		bcp->cong_reps =		congested_reps;
1614		bcp->disabled_period =		sec_2_cycles(disabled_period);
1615		bcp->giveup_limit =		giveup_limit;
1616	}
1617	return count;
1618}
1619
1620static const struct seq_operations uv_ptc_seq_ops = {
1621	.start		= ptc_seq_start,
1622	.next		= ptc_seq_next,
1623	.stop		= ptc_seq_stop,
1624	.show		= ptc_seq_show
1625};
1626
1627static int ptc_proc_open(struct inode *inode, struct file *file)
1628{
1629	return seq_open(file, &uv_ptc_seq_ops);
1630}
1631
1632static int tunables_open(struct inode *inode, struct file *file)
1633{
1634	return 0;
1635}
1636
1637static const struct file_operations proc_uv_ptc_operations = {
1638	.open		= ptc_proc_open,
1639	.read		= seq_read,
1640	.write		= ptc_proc_write,
1641	.llseek		= seq_lseek,
1642	.release	= seq_release,
1643};
1644
1645static const struct file_operations tunables_fops = {
1646	.open		= tunables_open,
1647	.read		= tunables_read,
1648	.write		= tunables_write,
1649	.llseek		= default_llseek,
1650};
1651
1652static int __init uv_ptc_init(void)
1653{
1654	struct proc_dir_entry *proc_uv_ptc;
1655
1656	if (!is_uv_system())
1657		return 0;
1658
1659	proc_uv_ptc = proc_create(UV_PTC_BASENAME, 0444, NULL,
1660				  &proc_uv_ptc_operations);
1661	if (!proc_uv_ptc) {
1662		printk(KERN_ERR "unable to create %s proc entry\n",
1663		       UV_PTC_BASENAME);
1664		return -EINVAL;
1665	}
1666
1667	tunables_dir = debugfs_create_dir(UV_BAU_TUNABLES_DIR, NULL);
1668	if (!tunables_dir) {
1669		printk(KERN_ERR "unable to create debugfs directory %s\n",
1670		       UV_BAU_TUNABLES_DIR);
1671		return -EINVAL;
1672	}
1673	tunables_file = debugfs_create_file(UV_BAU_TUNABLES_FILE, 0600,
1674					tunables_dir, NULL, &tunables_fops);
1675	if (!tunables_file) {
1676		printk(KERN_ERR "unable to create debugfs file %s\n",
1677		       UV_BAU_TUNABLES_FILE);
1678		return -EINVAL;
1679	}
1680	return 0;
1681}
1682
1683/*
1684 * Initialize the sending side's sending buffers.
1685 */
1686static void activation_descriptor_init(int node, int pnode, int base_pnode)
1687{
1688	int i;
1689	int cpu;
1690	int uv1 = 0;
1691	unsigned long gpa;
1692	unsigned long m;
1693	unsigned long n;
1694	size_t dsize;
1695	struct bau_desc *bau_desc;
1696	struct bau_desc *bd2;
1697	struct uv1_bau_msg_header *uv1_hdr;
1698	struct uv2_3_bau_msg_header *uv2_3_hdr;
1699	struct bau_control *bcp;
1700
1701	/*
1702	 * each bau_desc is 64 bytes; there are 8 (ITEMS_PER_DESC)
1703	 * per cpu; and one per cpu on the uvhub (ADP_SZ)
1704	 */
1705	dsize = sizeof(struct bau_desc) * ADP_SZ * ITEMS_PER_DESC;
1706	bau_desc = kmalloc_node(dsize, GFP_KERNEL, node);
1707	BUG_ON(!bau_desc);
1708
1709	gpa = uv_gpa(bau_desc);
1710	n = uv_gpa_to_gnode(gpa);
1711	m = uv_gpa_to_offset(gpa);
1712	if (is_uv1_hub())
1713		uv1 = 1;
1714
1715	/* the 14-bit pnode */
1716	write_mmr_descriptor_base(pnode, (n << UV_DESC_PSHIFT | m));
1717	/*
1718	 * Initializing all 8 (ITEMS_PER_DESC) descriptors for each
1719	 * cpu even though we only use the first one; one descriptor can
1720	 * describe a broadcast to 256 uv hubs.
1721	 */
1722	for (i = 0, bd2 = bau_desc; i < (ADP_SZ * ITEMS_PER_DESC); i++, bd2++) {
1723		memset(bd2, 0, sizeof(struct bau_desc));
1724		if (uv1) {
1725			uv1_hdr = &bd2->header.uv1_hdr;
1726			uv1_hdr->swack_flag =	1;
1727			/*
1728			 * The base_dest_nasid set in the message header
1729			 * is the nasid of the first uvhub in the partition.
1730			 * The bit map will indicate destination pnode numbers
1731			 * relative to that base. They may not be consecutive
1732			 * if nasid striding is being used.
1733			 */
1734			uv1_hdr->base_dest_nasid =
1735						UV_PNODE_TO_NASID(base_pnode);
1736			uv1_hdr->dest_subnodeid =	UV_LB_SUBNODEID;
1737			uv1_hdr->command =		UV_NET_ENDPOINT_INTD;
1738			uv1_hdr->int_both =		1;
1739			/*
1740			 * all others need to be set to zero:
1741			 *   fairness chaining multilevel count replied_to
1742			 */
1743		} else {
1744			/*
1745			 * BIOS uses legacy mode, but uv2 and uv3 hardware always
1746			 * uses native mode for selective broadcasts.
1747			 */
1748			uv2_3_hdr = &bd2->header.uv2_3_hdr;
1749			uv2_3_hdr->swack_flag =	1;
1750			uv2_3_hdr->base_dest_nasid =
1751						UV_PNODE_TO_NASID(base_pnode);
1752			uv2_3_hdr->dest_subnodeid =	UV_LB_SUBNODEID;
1753			uv2_3_hdr->command =		UV_NET_ENDPOINT_INTD;
1754		}
1755	}
1756	for_each_present_cpu(cpu) {
1757		if (pnode != uv_blade_to_pnode(uv_cpu_to_blade_id(cpu)))
1758			continue;
1759		bcp = &per_cpu(bau_control, cpu);
1760		bcp->descriptor_base = bau_desc;
1761	}
1762}
1763
1764/*
1765 * initialize the destination side's receiving buffers
1766 * entered for each uvhub in the partition
1767 * - node is first node (kernel memory notion) on the uvhub
1768 * - pnode is the uvhub's physical identifier
1769 */
1770static void pq_init(int node, int pnode)
1771{
1772	int cpu;
1773	size_t plsize;
1774	char *cp;
1775	void *vp;
1776	unsigned long pn;
1777	unsigned long first;
1778	unsigned long pn_first;
1779	unsigned long last;
1780	struct bau_pq_entry *pqp;
1781	struct bau_control *bcp;
1782
1783	plsize = (DEST_Q_SIZE + 1) * sizeof(struct bau_pq_entry);
1784	vp = kmalloc_node(plsize, GFP_KERNEL, node);
1785	pqp = (struct bau_pq_entry *)vp;
1786	BUG_ON(!pqp);
1787
1788	cp = (char *)pqp + 31;
1789	pqp = (struct bau_pq_entry *)(((unsigned long)cp >> 5) << 5);
1790
1791	for_each_present_cpu(cpu) {
1792		if (pnode != uv_cpu_to_pnode(cpu))
1793			continue;
1794		/* for every cpu on this pnode: */
1795		bcp = &per_cpu(bau_control, cpu);
1796		bcp->queue_first	= pqp;
1797		bcp->bau_msg_head	= pqp;
1798		bcp->queue_last		= pqp + (DEST_Q_SIZE - 1);
1799	}
1800	/*
1801	 * need the gnode of where the memory was really allocated
1802	 */
1803	pn = uv_gpa_to_gnode(uv_gpa(pqp));
1804	first = uv_physnodeaddr(pqp);
1805	pn_first = ((unsigned long)pn << UV_PAYLOADQ_PNODE_SHIFT) | first;
1806	last = uv_physnodeaddr(pqp + (DEST_Q_SIZE - 1));
1807	write_mmr_payload_first(pnode, pn_first);
1808	write_mmr_payload_tail(pnode, first);
1809	write_mmr_payload_last(pnode, last);
1810	write_gmmr_sw_ack(pnode, 0xffffUL);
1811
1812	/* in effect, all msg_type's are set to MSG_NOOP */
1813	memset(pqp, 0, sizeof(struct bau_pq_entry) * DEST_Q_SIZE);
1814}
1815
1816/*
1817 * Initialization of each UV hub's structures
1818 */
1819static void __init init_uvhub(int uvhub, int vector, int base_pnode)
1820{
1821	int node;
1822	int pnode;
1823	unsigned long apicid;
1824
1825	node = uvhub_to_first_node(uvhub);
1826	pnode = uv_blade_to_pnode(uvhub);
1827
1828	activation_descriptor_init(node, pnode, base_pnode);
1829
1830	pq_init(node, pnode);
1831	/*
1832	 * The below initialization can't be in firmware because the
1833	 * messaging IRQ will be determined by the OS.
1834	 */
1835	apicid = uvhub_to_first_apicid(uvhub) | uv_apicid_hibits;
1836	write_mmr_data_config(pnode, ((apicid << 32) | vector));
1837}
1838
1839/*
1840 * We will set BAU_MISC_CONTROL with a timeout period.
1841 * But the BIOS has set UVH_AGING_PRESCALE_SEL and UVH_TRANSACTION_TIMEOUT.
1842 * So the destination timeout period has to be calculated from them.
1843 */
1844static int calculate_destination_timeout(void)
1845{
1846	unsigned long mmr_image;
1847	int mult1;
1848	int mult2;
1849	int index;
1850	int base;
1851	int ret;
1852	unsigned long ts_ns;
1853
1854	if (is_uv1_hub()) {
1855		mult1 = SOFTACK_TIMEOUT_PERIOD & BAU_MISC_CONTROL_MULT_MASK;
1856		mmr_image = uv_read_local_mmr(UVH_AGING_PRESCALE_SEL);
1857		index = (mmr_image >> BAU_URGENCY_7_SHIFT) & BAU_URGENCY_7_MASK;
1858		mmr_image = uv_read_local_mmr(UVH_TRANSACTION_TIMEOUT);
1859		mult2 = (mmr_image >> BAU_TRANS_SHIFT) & BAU_TRANS_MASK;
1860		ts_ns = timeout_base_ns[index];
1861		ts_ns *= (mult1 * mult2);
1862		ret = ts_ns / 1000;
1863	} else {
1864		/* same destination timeout for uv2 and uv3 */
1865		/* 4 bits  0/1 for 10/80us base, 3 bits of multiplier */
1866		mmr_image = uv_read_local_mmr(UVH_LB_BAU_MISC_CONTROL);
1867		mmr_image = (mmr_image & UV_SA_MASK) >> UV_SA_SHFT;
1868		if (mmr_image & (1L << UV2_ACK_UNITS_SHFT))
1869			base = 80;
1870		else
1871			base = 10;
1872		mult1 = mmr_image & UV2_ACK_MASK;
1873		ret = mult1 * base;
1874	}
1875	return ret;
1876}
1877
1878static void __init init_per_cpu_tunables(void)
1879{
1880	int cpu;
1881	struct bau_control *bcp;
1882
1883	for_each_present_cpu(cpu) {
1884		bcp = &per_cpu(bau_control, cpu);
1885		bcp->baudisabled		= 0;
1886		if (nobau)
1887			bcp->nobau		= 1;
1888		bcp->statp			= &per_cpu(ptcstats, cpu);
1889		/* time interval to catch a hardware stay-busy bug */
1890		bcp->timeout_interval		= usec_2_cycles(2*timeout_us);
1891		bcp->max_concurr		= max_concurr;
1892		bcp->max_concurr_const		= max_concurr;
1893		bcp->plugged_delay		= plugged_delay;
1894		bcp->plugsb4reset		= plugsb4reset;
1895		bcp->timeoutsb4reset		= timeoutsb4reset;
1896		bcp->ipi_reset_limit		= ipi_reset_limit;
1897		bcp->complete_threshold		= complete_threshold;
1898		bcp->cong_response_us		= congested_respns_us;
1899		bcp->cong_reps			= congested_reps;
1900		bcp->disabled_period =		sec_2_cycles(disabled_period);
1901		bcp->giveup_limit =		giveup_limit;
1902		spin_lock_init(&bcp->queue_lock);
1903		spin_lock_init(&bcp->uvhub_lock);
1904		spin_lock_init(&bcp->disable_lock);
1905	}
1906}
1907
1908/*
1909 * Scan all cpus to collect blade and socket summaries.
1910 */
1911static int __init get_cpu_topology(int base_pnode,
1912					struct uvhub_desc *uvhub_descs,
1913					unsigned char *uvhub_mask)
1914{
1915	int cpu;
1916	int pnode;
1917	int uvhub;
1918	int socket;
1919	struct bau_control *bcp;
1920	struct uvhub_desc *bdp;
1921	struct socket_desc *sdp;
1922
1923	for_each_present_cpu(cpu) {
1924		bcp = &per_cpu(bau_control, cpu);
1925
1926		memset(bcp, 0, sizeof(struct bau_control));
1927
1928		pnode = uv_cpu_hub_info(cpu)->pnode;
1929		if ((pnode - base_pnode) >= UV_DISTRIBUTION_SIZE) {
1930			printk(KERN_EMERG
1931				"cpu %d pnode %d-%d beyond %d; BAU disabled\n",
1932				cpu, pnode, base_pnode, UV_DISTRIBUTION_SIZE);
1933			return 1;
1934		}
1935
1936		bcp->osnode = cpu_to_node(cpu);
1937		bcp->partition_base_pnode = base_pnode;
1938
1939		uvhub = uv_cpu_hub_info(cpu)->numa_blade_id;
1940		*(uvhub_mask + (uvhub/8)) |= (1 << (uvhub%8));
1941		bdp = &uvhub_descs[uvhub];
1942
1943		bdp->num_cpus++;
1944		bdp->uvhub = uvhub;
1945		bdp->pnode = pnode;
1946
1947		/* kludge: 'assuming' one node per socket, and assuming that
1948		   disabling a socket just leaves a gap in node numbers */
1949		socket = bcp->osnode & 1;
1950		bdp->socket_mask |= (1 << socket);
1951		sdp = &bdp->socket[socket];
1952		sdp->cpu_number[sdp->num_cpus] = cpu;
1953		sdp->num_cpus++;
1954		if (sdp->num_cpus > MAX_CPUS_PER_SOCKET) {
1955			printk(KERN_EMERG "%d cpus per socket invalid\n",
1956				sdp->num_cpus);
1957			return 1;
1958		}
1959	}
1960	return 0;
1961}
1962
1963/*
1964 * Each socket is to get a local array of pnodes/hubs.
1965 */
1966static void make_per_cpu_thp(struct bau_control *smaster)
1967{
1968	int cpu;
1969	size_t hpsz = sizeof(struct hub_and_pnode) * num_possible_cpus();
1970
1971	smaster->thp = kmalloc_node(hpsz, GFP_KERNEL, smaster->osnode);
1972	memset(smaster->thp, 0, hpsz);
1973	for_each_present_cpu(cpu) {
1974		smaster->thp[cpu].pnode = uv_cpu_hub_info(cpu)->pnode;
1975		smaster->thp[cpu].uvhub = uv_cpu_hub_info(cpu)->numa_blade_id;
1976	}
1977}
1978
1979/*
1980 * Each uvhub is to get a local cpumask.
1981 */
1982static void make_per_hub_cpumask(struct bau_control *hmaster)
1983{
1984	int sz = sizeof(cpumask_t);
1985
1986	hmaster->cpumask = kzalloc_node(sz, GFP_KERNEL, hmaster->osnode);
1987}
1988
1989/*
1990 * Initialize all the per_cpu information for the cpu's on a given socket,
1991 * given what has been gathered into the socket_desc struct.
1992 * And reports the chosen hub and socket masters back to the caller.
1993 */
1994static int scan_sock(struct socket_desc *sdp, struct uvhub_desc *bdp,
1995			struct bau_control **smasterp,
1996			struct bau_control **hmasterp)
1997{
1998	int i;
1999	int cpu;
2000	struct bau_control *bcp;
2001
2002	for (i = 0; i < sdp->num_cpus; i++) {
2003		cpu = sdp->cpu_number[i];
2004		bcp = &per_cpu(bau_control, cpu);
2005		bcp->cpu = cpu;
2006		if (i == 0) {
2007			*smasterp = bcp;
2008			if (!(*hmasterp))
2009				*hmasterp = bcp;
2010		}
2011		bcp->cpus_in_uvhub = bdp->num_cpus;
2012		bcp->cpus_in_socket = sdp->num_cpus;
2013		bcp->socket_master = *smasterp;
2014		bcp->uvhub = bdp->uvhub;
2015		if (is_uv1_hub())
2016			bcp->uvhub_version = 1;
2017		else if (is_uv2_hub())
2018			bcp->uvhub_version = 2;
2019		else if (is_uv3_hub())
2020			bcp->uvhub_version = 3;
2021		else {
2022			printk(KERN_EMERG "uvhub version not 1, 2 or 3\n");
2023			return 1;
2024		}
2025		bcp->uvhub_master = *hmasterp;
2026		bcp->uvhub_cpu = uv_cpu_hub_info(cpu)->blade_processor_id;
2027		if (bcp->uvhub_cpu >= MAX_CPUS_PER_UVHUB) {
2028			printk(KERN_EMERG "%d cpus per uvhub invalid\n",
2029				bcp->uvhub_cpu);
2030			return 1;
2031		}
2032	}
2033	return 0;
2034}
2035
2036/*
2037 * Summarize the blade and socket topology into the per_cpu structures.
2038 */
2039static int __init summarize_uvhub_sockets(int nuvhubs,
2040			struct uvhub_desc *uvhub_descs,
2041			unsigned char *uvhub_mask)
2042{
2043	int socket;
2044	int uvhub;
2045	unsigned short socket_mask;
2046
2047	for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
2048		struct uvhub_desc *bdp;
2049		struct bau_control *smaster = NULL;
2050		struct bau_control *hmaster = NULL;
2051
2052		if (!(*(uvhub_mask + (uvhub/8)) & (1 << (uvhub%8))))
2053			continue;
2054
2055		bdp = &uvhub_descs[uvhub];
2056		socket_mask = bdp->socket_mask;
2057		socket = 0;
2058		while (socket_mask) {
2059			struct socket_desc *sdp;
2060			if ((socket_mask & 1)) {
2061				sdp = &bdp->socket[socket];
2062				if (scan_sock(sdp, bdp, &smaster, &hmaster))
2063					return 1;
2064				make_per_cpu_thp(smaster);
2065			}
2066			socket++;
2067			socket_mask = (socket_mask >> 1);
2068		}
2069		make_per_hub_cpumask(hmaster);
2070	}
2071	return 0;
2072}
2073
2074/*
2075 * initialize the bau_control structure for each cpu
2076 */
2077static int __init init_per_cpu(int nuvhubs, int base_part_pnode)
2078{
2079	unsigned char *uvhub_mask;
2080	void *vp;
2081	struct uvhub_desc *uvhub_descs;
2082
2083	timeout_us = calculate_destination_timeout();
2084
2085	vp = kmalloc(nuvhubs * sizeof(struct uvhub_desc), GFP_KERNEL);
2086	uvhub_descs = (struct uvhub_desc *)vp;
2087	memset(uvhub_descs, 0, nuvhubs * sizeof(struct uvhub_desc));
2088	uvhub_mask = kzalloc((nuvhubs+7)/8, GFP_KERNEL);
2089
2090	if (get_cpu_topology(base_part_pnode, uvhub_descs, uvhub_mask))
2091		goto fail;
2092
2093	if (summarize_uvhub_sockets(nuvhubs, uvhub_descs, uvhub_mask))
2094		goto fail;
2095
2096	kfree(uvhub_descs);
2097	kfree(uvhub_mask);
2098	init_per_cpu_tunables();
2099	return 0;
2100
2101fail:
2102	kfree(uvhub_descs);
2103	kfree(uvhub_mask);
2104	return 1;
2105}
2106
2107/*
2108 * Initialization of BAU-related structures
2109 */
2110static int __init uv_bau_init(void)
2111{
2112	int uvhub;
2113	int pnode;
2114	int nuvhubs;
2115	int cur_cpu;
2116	int cpus;
2117	int vector;
2118	cpumask_var_t *mask;
2119
2120	if (!is_uv_system())
2121		return 0;
2122
2123	for_each_possible_cpu(cur_cpu) {
2124		mask = &per_cpu(uv_flush_tlb_mask, cur_cpu);
2125		zalloc_cpumask_var_node(mask, GFP_KERNEL, cpu_to_node(cur_cpu));
2126	}
2127
2128	nuvhubs = uv_num_possible_blades();
2129	congested_cycles = usec_2_cycles(congested_respns_us);
2130
2131	uv_base_pnode = 0x7fffffff;
2132	for (uvhub = 0; uvhub < nuvhubs; uvhub++) {
2133		cpus = uv_blade_nr_possible_cpus(uvhub);
2134		if (cpus && (uv_blade_to_pnode(uvhub) < uv_base_pnode))
2135			uv_base_pnode = uv_blade_to_pnode(uvhub);
2136	}
2137
2138	enable_timeouts();
2139
2140	if (init_per_cpu(nuvhubs, uv_base_pnode)) {
2141		set_bau_off();
2142		nobau_perm = 1;
2143		return 0;
2144	}
2145
2146	vector = UV_BAU_MESSAGE;
2147	for_each_possible_blade(uvhub) {
2148		if (uv_blade_nr_possible_cpus(uvhub))
2149			init_uvhub(uvhub, vector, uv_base_pnode);
2150	}
2151
2152	alloc_intr_gate(vector, uv_bau_message_intr1);
2153
2154	for_each_possible_blade(uvhub) {
2155		if (uv_blade_nr_possible_cpus(uvhub)) {
2156			unsigned long val;
2157			unsigned long mmr;
2158			pnode = uv_blade_to_pnode(uvhub);
2159			/* INIT the bau */
2160			val = 1L << 63;
2161			write_gmmr_activation(pnode, val);
2162			mmr = 1; /* should be 1 to broadcast to both sockets */
2163			if (!is_uv1_hub())
2164				write_mmr_data_broadcast(pnode, mmr);
2165		}
2166	}
2167
2168	return 0;
2169}
2170core_initcall(uv_bau_init);
2171fs_initcall(uv_ptc_init);
2172