xref: /openbmc/linux/arch/sparc/kernel/smp_64.c (revision 1e726951)
1 // SPDX-License-Identifier: GPL-2.0
2 /* smp.c: Sparc64 SMP support.
3  *
4  * Copyright (C) 1997, 2007, 2008 David S. Miller (davem@davemloft.net)
5  */
6 
7 #include <linux/export.h>
8 #include <linux/kernel.h>
9 #include <linux/sched/mm.h>
10 #include <linux/sched/hotplug.h>
11 #include <linux/mm.h>
12 #include <linux/pagemap.h>
13 #include <linux/threads.h>
14 #include <linux/smp.h>
15 #include <linux/interrupt.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/spinlock.h>
20 #include <linux/fs.h>
21 #include <linux/seq_file.h>
22 #include <linux/cache.h>
23 #include <linux/jiffies.h>
24 #include <linux/profile.h>
25 #include <linux/memblock.h>
26 #include <linux/vmalloc.h>
27 #include <linux/ftrace.h>
28 #include <linux/cpu.h>
29 #include <linux/slab.h>
30 #include <linux/kgdb.h>
31 
32 #include <asm/head.h>
33 #include <asm/ptrace.h>
34 #include <linux/atomic.h>
35 #include <asm/tlbflush.h>
36 #include <asm/mmu_context.h>
37 #include <asm/cpudata.h>
38 #include <asm/hvtramp.h>
39 #include <asm/io.h>
40 #include <asm/timer.h>
41 #include <asm/setup.h>
42 
43 #include <asm/irq.h>
44 #include <asm/irq_regs.h>
45 #include <asm/page.h>
46 #include <asm/oplib.h>
47 #include <linux/uaccess.h>
48 #include <asm/starfire.h>
49 #include <asm/tlb.h>
50 #include <asm/pgalloc.h>
51 #include <asm/sections.h>
52 #include <asm/prom.h>
53 #include <asm/mdesc.h>
54 #include <asm/ldc.h>
55 #include <asm/hypervisor.h>
56 #include <asm/pcr.h>
57 
58 #include "cpumap.h"
59 #include "kernel.h"
60 
61 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
62 cpumask_t cpu_core_map[NR_CPUS] __read_mostly =
63 	{ [0 ... NR_CPUS-1] = CPU_MASK_NONE };
64 
65 cpumask_t cpu_core_sib_map[NR_CPUS] __read_mostly = {
66 	[0 ... NR_CPUS-1] = CPU_MASK_NONE };
67 
68 cpumask_t cpu_core_sib_cache_map[NR_CPUS] __read_mostly = {
69 	[0 ... NR_CPUS - 1] = CPU_MASK_NONE };
70 
71 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
72 EXPORT_SYMBOL(cpu_core_map);
73 EXPORT_SYMBOL(cpu_core_sib_map);
74 EXPORT_SYMBOL(cpu_core_sib_cache_map);
75 
76 static cpumask_t smp_commenced_mask;
77 
78 static DEFINE_PER_CPU(bool, poke);
79 static bool cpu_poke;
80 
81 void smp_info(struct seq_file *m)
82 {
83 	int i;
84 
85 	seq_printf(m, "State:\n");
86 	for_each_online_cpu(i)
87 		seq_printf(m, "CPU%d:\t\tonline\n", i);
88 }
89 
90 void smp_bogo(struct seq_file *m)
91 {
92 	int i;
93 
94 	for_each_online_cpu(i)
95 		seq_printf(m,
96 			   "Cpu%dClkTck\t: %016lx\n",
97 			   i, cpu_data(i).clock_tick);
98 }
99 
100 extern void setup_sparc64_timer(void);
101 
102 static volatile unsigned long callin_flag = 0;
103 
104 void smp_callin(void)
105 {
106 	int cpuid = hard_smp_processor_id();
107 
108 	__local_per_cpu_offset = __per_cpu_offset(cpuid);
109 
110 	if (tlb_type == hypervisor)
111 		sun4v_ktsb_register();
112 
113 	__flush_tlb_all();
114 
115 	setup_sparc64_timer();
116 
117 	if (cheetah_pcache_forced_on)
118 		cheetah_enable_pcache();
119 
120 	callin_flag = 1;
121 	__asm__ __volatile__("membar #Sync\n\t"
122 			     "flush  %%g6" : : : "memory");
123 
124 	/* Clear this or we will die instantly when we
125 	 * schedule back to this idler...
126 	 */
127 	current_thread_info()->new_child = 0;
128 
129 	/* Attach to the address space of init_task. */
130 	mmgrab(&init_mm);
131 	current->active_mm = &init_mm;
132 
133 	/* inform the notifiers about the new cpu */
134 	notify_cpu_starting(cpuid);
135 
136 	while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
137 		rmb();
138 
139 	set_cpu_online(cpuid, true);
140 
141 	local_irq_enable();
142 
143 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
144 }
145 
146 void cpu_panic(void)
147 {
148 	printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
149 	panic("SMP bolixed\n");
150 }
151 
152 /* This tick register synchronization scheme is taken entirely from
153  * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
154  *
155  * The only change I've made is to rework it so that the master
156  * initiates the synchonization instead of the slave. -DaveM
157  */
158 
159 #define MASTER	0
160 #define SLAVE	(SMP_CACHE_BYTES/sizeof(unsigned long))
161 
162 #define NUM_ROUNDS	64	/* magic value */
163 #define NUM_ITERS	5	/* likewise */
164 
165 static DEFINE_RAW_SPINLOCK(itc_sync_lock);
166 static unsigned long go[SLAVE + 1];
167 
168 #define DEBUG_TICK_SYNC	0
169 
170 static inline long get_delta (long *rt, long *master)
171 {
172 	unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
173 	unsigned long tcenter, t0, t1, tm;
174 	unsigned long i;
175 
176 	for (i = 0; i < NUM_ITERS; i++) {
177 		t0 = tick_ops->get_tick();
178 		go[MASTER] = 1;
179 		membar_safe("#StoreLoad");
180 		while (!(tm = go[SLAVE]))
181 			rmb();
182 		go[SLAVE] = 0;
183 		wmb();
184 		t1 = tick_ops->get_tick();
185 
186 		if (t1 - t0 < best_t1 - best_t0)
187 			best_t0 = t0, best_t1 = t1, best_tm = tm;
188 	}
189 
190 	*rt = best_t1 - best_t0;
191 	*master = best_tm - best_t0;
192 
193 	/* average best_t0 and best_t1 without overflow: */
194 	tcenter = (best_t0/2 + best_t1/2);
195 	if (best_t0 % 2 + best_t1 % 2 == 2)
196 		tcenter++;
197 	return tcenter - best_tm;
198 }
199 
200 void smp_synchronize_tick_client(void)
201 {
202 	long i, delta, adj, adjust_latency = 0, done = 0;
203 	unsigned long flags, rt, master_time_stamp;
204 #if DEBUG_TICK_SYNC
205 	struct {
206 		long rt;	/* roundtrip time */
207 		long master;	/* master's timestamp */
208 		long diff;	/* difference between midpoint and master's timestamp */
209 		long lat;	/* estimate of itc adjustment latency */
210 	} t[NUM_ROUNDS];
211 #endif
212 
213 	go[MASTER] = 1;
214 
215 	while (go[MASTER])
216 		rmb();
217 
218 	local_irq_save(flags);
219 	{
220 		for (i = 0; i < NUM_ROUNDS; i++) {
221 			delta = get_delta(&rt, &master_time_stamp);
222 			if (delta == 0)
223 				done = 1;	/* let's lock on to this... */
224 
225 			if (!done) {
226 				if (i > 0) {
227 					adjust_latency += -delta;
228 					adj = -delta + adjust_latency/4;
229 				} else
230 					adj = -delta;
231 
232 				tick_ops->add_tick(adj);
233 			}
234 #if DEBUG_TICK_SYNC
235 			t[i].rt = rt;
236 			t[i].master = master_time_stamp;
237 			t[i].diff = delta;
238 			t[i].lat = adjust_latency/4;
239 #endif
240 		}
241 	}
242 	local_irq_restore(flags);
243 
244 #if DEBUG_TICK_SYNC
245 	for (i = 0; i < NUM_ROUNDS; i++)
246 		printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
247 		       t[i].rt, t[i].master, t[i].diff, t[i].lat);
248 #endif
249 
250 	printk(KERN_INFO "CPU %d: synchronized TICK with master CPU "
251 	       "(last diff %ld cycles, maxerr %lu cycles)\n",
252 	       smp_processor_id(), delta, rt);
253 }
254 
255 static void smp_start_sync_tick_client(int cpu);
256 
257 static void smp_synchronize_one_tick(int cpu)
258 {
259 	unsigned long flags, i;
260 
261 	go[MASTER] = 0;
262 
263 	smp_start_sync_tick_client(cpu);
264 
265 	/* wait for client to be ready */
266 	while (!go[MASTER])
267 		rmb();
268 
269 	/* now let the client proceed into his loop */
270 	go[MASTER] = 0;
271 	membar_safe("#StoreLoad");
272 
273 	raw_spin_lock_irqsave(&itc_sync_lock, flags);
274 	{
275 		for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
276 			while (!go[MASTER])
277 				rmb();
278 			go[MASTER] = 0;
279 			wmb();
280 			go[SLAVE] = tick_ops->get_tick();
281 			membar_safe("#StoreLoad");
282 		}
283 	}
284 	raw_spin_unlock_irqrestore(&itc_sync_lock, flags);
285 }
286 
287 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
288 static void ldom_startcpu_cpuid(unsigned int cpu, unsigned long thread_reg,
289 				void **descrp)
290 {
291 	extern unsigned long sparc64_ttable_tl0;
292 	extern unsigned long kern_locked_tte_data;
293 	struct hvtramp_descr *hdesc;
294 	unsigned long trampoline_ra;
295 	struct trap_per_cpu *tb;
296 	u64 tte_vaddr, tte_data;
297 	unsigned long hv_err;
298 	int i;
299 
300 	hdesc = kzalloc(sizeof(*hdesc) +
301 			(sizeof(struct hvtramp_mapping) *
302 			 num_kernel_image_mappings - 1),
303 			GFP_KERNEL);
304 	if (!hdesc) {
305 		printk(KERN_ERR "ldom_startcpu_cpuid: Cannot allocate "
306 		       "hvtramp_descr.\n");
307 		return;
308 	}
309 	*descrp = hdesc;
310 
311 	hdesc->cpu = cpu;
312 	hdesc->num_mappings = num_kernel_image_mappings;
313 
314 	tb = &trap_block[cpu];
315 
316 	hdesc->fault_info_va = (unsigned long) &tb->fault_info;
317 	hdesc->fault_info_pa = kimage_addr_to_ra(&tb->fault_info);
318 
319 	hdesc->thread_reg = thread_reg;
320 
321 	tte_vaddr = (unsigned long) KERNBASE;
322 	tte_data = kern_locked_tte_data;
323 
324 	for (i = 0; i < hdesc->num_mappings; i++) {
325 		hdesc->maps[i].vaddr = tte_vaddr;
326 		hdesc->maps[i].tte   = tte_data;
327 		tte_vaddr += 0x400000;
328 		tte_data  += 0x400000;
329 	}
330 
331 	trampoline_ra = kimage_addr_to_ra(hv_cpu_startup);
332 
333 	hv_err = sun4v_cpu_start(cpu, trampoline_ra,
334 				 kimage_addr_to_ra(&sparc64_ttable_tl0),
335 				 __pa(hdesc));
336 	if (hv_err)
337 		printk(KERN_ERR "ldom_startcpu_cpuid: sun4v_cpu_start() "
338 		       "gives error %lu\n", hv_err);
339 }
340 #endif
341 
342 extern unsigned long sparc64_cpu_startup;
343 
344 /* The OBP cpu startup callback truncates the 3rd arg cookie to
345  * 32-bits (I think) so to be safe we have it read the pointer
346  * contained here so we work on >4GB machines. -DaveM
347  */
348 static struct thread_info *cpu_new_thread = NULL;
349 
350 static int smp_boot_one_cpu(unsigned int cpu, struct task_struct *idle)
351 {
352 	unsigned long entry =
353 		(unsigned long)(&sparc64_cpu_startup);
354 	unsigned long cookie =
355 		(unsigned long)(&cpu_new_thread);
356 	void *descr = NULL;
357 	int timeout, ret;
358 
359 	callin_flag = 0;
360 	cpu_new_thread = task_thread_info(idle);
361 
362 	if (tlb_type == hypervisor) {
363 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
364 		if (ldom_domaining_enabled)
365 			ldom_startcpu_cpuid(cpu,
366 					    (unsigned long) cpu_new_thread,
367 					    &descr);
368 		else
369 #endif
370 			prom_startcpu_cpuid(cpu, entry, cookie);
371 	} else {
372 		struct device_node *dp = of_find_node_by_cpuid(cpu);
373 
374 		prom_startcpu(dp->phandle, entry, cookie);
375 	}
376 
377 	for (timeout = 0; timeout < 50000; timeout++) {
378 		if (callin_flag)
379 			break;
380 		udelay(100);
381 	}
382 
383 	if (callin_flag) {
384 		ret = 0;
385 	} else {
386 		printk("Processor %d is stuck.\n", cpu);
387 		ret = -ENODEV;
388 	}
389 	cpu_new_thread = NULL;
390 
391 	kfree(descr);
392 
393 	return ret;
394 }
395 
396 static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
397 {
398 	u64 result, target;
399 	int stuck, tmp;
400 
401 	if (this_is_starfire) {
402 		/* map to real upaid */
403 		cpu = (((cpu & 0x3c) << 1) |
404 			((cpu & 0x40) >> 4) |
405 			(cpu & 0x3));
406 	}
407 
408 	target = (cpu << 14) | 0x70;
409 again:
410 	/* Ok, this is the real Spitfire Errata #54.
411 	 * One must read back from a UDB internal register
412 	 * after writes to the UDB interrupt dispatch, but
413 	 * before the membar Sync for that write.
414 	 * So we use the high UDB control register (ASI 0x7f,
415 	 * ADDR 0x20) for the dummy read. -DaveM
416 	 */
417 	tmp = 0x40;
418 	__asm__ __volatile__(
419 	"wrpr	%1, %2, %%pstate\n\t"
420 	"stxa	%4, [%0] %3\n\t"
421 	"stxa	%5, [%0+%8] %3\n\t"
422 	"add	%0, %8, %0\n\t"
423 	"stxa	%6, [%0+%8] %3\n\t"
424 	"membar	#Sync\n\t"
425 	"stxa	%%g0, [%7] %3\n\t"
426 	"membar	#Sync\n\t"
427 	"mov	0x20, %%g1\n\t"
428 	"ldxa	[%%g1] 0x7f, %%g0\n\t"
429 	"membar	#Sync"
430 	: "=r" (tmp)
431 	: "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
432 	  "r" (data0), "r" (data1), "r" (data2), "r" (target),
433 	  "r" (0x10), "0" (tmp)
434         : "g1");
435 
436 	/* NOTE: PSTATE_IE is still clear. */
437 	stuck = 100000;
438 	do {
439 		__asm__ __volatile__("ldxa [%%g0] %1, %0"
440 			: "=r" (result)
441 			: "i" (ASI_INTR_DISPATCH_STAT));
442 		if (result == 0) {
443 			__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
444 					     : : "r" (pstate));
445 			return;
446 		}
447 		stuck -= 1;
448 		if (stuck == 0)
449 			break;
450 	} while (result & 0x1);
451 	__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
452 			     : : "r" (pstate));
453 	if (stuck == 0) {
454 		printk("CPU[%d]: mondo stuckage result[%016llx]\n",
455 		       smp_processor_id(), result);
456 	} else {
457 		udelay(2);
458 		goto again;
459 	}
460 }
461 
462 static void spitfire_xcall_deliver(struct trap_per_cpu *tb, int cnt)
463 {
464 	u64 *mondo, data0, data1, data2;
465 	u16 *cpu_list;
466 	u64 pstate;
467 	int i;
468 
469 	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
470 	cpu_list = __va(tb->cpu_list_pa);
471 	mondo = __va(tb->cpu_mondo_block_pa);
472 	data0 = mondo[0];
473 	data1 = mondo[1];
474 	data2 = mondo[2];
475 	for (i = 0; i < cnt; i++)
476 		spitfire_xcall_helper(data0, data1, data2, pstate, cpu_list[i]);
477 }
478 
479 /* Cheetah now allows to send the whole 64-bytes of data in the interrupt
480  * packet, but we have no use for that.  However we do take advantage of
481  * the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
482  */
483 static void cheetah_xcall_deliver(struct trap_per_cpu *tb, int cnt)
484 {
485 	int nack_busy_id, is_jbus, need_more;
486 	u64 *mondo, pstate, ver, busy_mask;
487 	u16 *cpu_list;
488 
489 	cpu_list = __va(tb->cpu_list_pa);
490 	mondo = __va(tb->cpu_mondo_block_pa);
491 
492 	/* Unfortunately, someone at Sun had the brilliant idea to make the
493 	 * busy/nack fields hard-coded by ITID number for this Ultra-III
494 	 * derivative processor.
495 	 */
496 	__asm__ ("rdpr %%ver, %0" : "=r" (ver));
497 	is_jbus = ((ver >> 32) == __JALAPENO_ID ||
498 		   (ver >> 32) == __SERRANO_ID);
499 
500 	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
501 
502 retry:
503 	need_more = 0;
504 	__asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
505 			     : : "r" (pstate), "i" (PSTATE_IE));
506 
507 	/* Setup the dispatch data registers. */
508 	__asm__ __volatile__("stxa	%0, [%3] %6\n\t"
509 			     "stxa	%1, [%4] %6\n\t"
510 			     "stxa	%2, [%5] %6\n\t"
511 			     "membar	#Sync\n\t"
512 			     : /* no outputs */
513 			     : "r" (mondo[0]), "r" (mondo[1]), "r" (mondo[2]),
514 			       "r" (0x40), "r" (0x50), "r" (0x60),
515 			       "i" (ASI_INTR_W));
516 
517 	nack_busy_id = 0;
518 	busy_mask = 0;
519 	{
520 		int i;
521 
522 		for (i = 0; i < cnt; i++) {
523 			u64 target, nr;
524 
525 			nr = cpu_list[i];
526 			if (nr == 0xffff)
527 				continue;
528 
529 			target = (nr << 14) | 0x70;
530 			if (is_jbus) {
531 				busy_mask |= (0x1UL << (nr * 2));
532 			} else {
533 				target |= (nack_busy_id << 24);
534 				busy_mask |= (0x1UL <<
535 					      (nack_busy_id * 2));
536 			}
537 			__asm__ __volatile__(
538 				"stxa	%%g0, [%0] %1\n\t"
539 				"membar	#Sync\n\t"
540 				: /* no outputs */
541 				: "r" (target), "i" (ASI_INTR_W));
542 			nack_busy_id++;
543 			if (nack_busy_id == 32) {
544 				need_more = 1;
545 				break;
546 			}
547 		}
548 	}
549 
550 	/* Now, poll for completion. */
551 	{
552 		u64 dispatch_stat, nack_mask;
553 		long stuck;
554 
555 		stuck = 100000 * nack_busy_id;
556 		nack_mask = busy_mask << 1;
557 		do {
558 			__asm__ __volatile__("ldxa	[%%g0] %1, %0"
559 					     : "=r" (dispatch_stat)
560 					     : "i" (ASI_INTR_DISPATCH_STAT));
561 			if (!(dispatch_stat & (busy_mask | nack_mask))) {
562 				__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
563 						     : : "r" (pstate));
564 				if (unlikely(need_more)) {
565 					int i, this_cnt = 0;
566 					for (i = 0; i < cnt; i++) {
567 						if (cpu_list[i] == 0xffff)
568 							continue;
569 						cpu_list[i] = 0xffff;
570 						this_cnt++;
571 						if (this_cnt == 32)
572 							break;
573 					}
574 					goto retry;
575 				}
576 				return;
577 			}
578 			if (!--stuck)
579 				break;
580 		} while (dispatch_stat & busy_mask);
581 
582 		__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
583 				     : : "r" (pstate));
584 
585 		if (dispatch_stat & busy_mask) {
586 			/* Busy bits will not clear, continue instead
587 			 * of freezing up on this cpu.
588 			 */
589 			printk("CPU[%d]: mondo stuckage result[%016llx]\n",
590 			       smp_processor_id(), dispatch_stat);
591 		} else {
592 			int i, this_busy_nack = 0;
593 
594 			/* Delay some random time with interrupts enabled
595 			 * to prevent deadlock.
596 			 */
597 			udelay(2 * nack_busy_id);
598 
599 			/* Clear out the mask bits for cpus which did not
600 			 * NACK us.
601 			 */
602 			for (i = 0; i < cnt; i++) {
603 				u64 check_mask, nr;
604 
605 				nr = cpu_list[i];
606 				if (nr == 0xffff)
607 					continue;
608 
609 				if (is_jbus)
610 					check_mask = (0x2UL << (2*nr));
611 				else
612 					check_mask = (0x2UL <<
613 						      this_busy_nack);
614 				if ((dispatch_stat & check_mask) == 0)
615 					cpu_list[i] = 0xffff;
616 				this_busy_nack += 2;
617 				if (this_busy_nack == 64)
618 					break;
619 			}
620 
621 			goto retry;
622 		}
623 	}
624 }
625 
626 #define	CPU_MONDO_COUNTER(cpuid)	(cpu_mondo_counter[cpuid])
627 #define	MONDO_USEC_WAIT_MIN		2
628 #define	MONDO_USEC_WAIT_MAX		100
629 #define	MONDO_RETRY_LIMIT		500000
630 
631 /* Multi-cpu list version.
632  *
633  * Deliver xcalls to 'cnt' number of cpus in 'cpu_list'.
634  * Sometimes not all cpus receive the mondo, requiring us to re-send
635  * the mondo until all cpus have received, or cpus are truly stuck
636  * unable to receive mondo, and we timeout.
637  * Occasionally a target cpu strand is borrowed briefly by hypervisor to
638  * perform guest service, such as PCIe error handling. Consider the
639  * service time, 1 second overall wait is reasonable for 1 cpu.
640  * Here two in-between mondo check wait time are defined: 2 usec for
641  * single cpu quick turn around and up to 100usec for large cpu count.
642  * Deliver mondo to large number of cpus could take longer, we adjusts
643  * the retry count as long as target cpus are making forward progress.
644  */
645 static void hypervisor_xcall_deliver(struct trap_per_cpu *tb, int cnt)
646 {
647 	int this_cpu, tot_cpus, prev_sent, i, rem;
648 	int usec_wait, retries, tot_retries;
649 	u16 first_cpu = 0xffff;
650 	unsigned long xc_rcvd = 0;
651 	unsigned long status;
652 	int ecpuerror_id = 0;
653 	int enocpu_id = 0;
654 	u16 *cpu_list;
655 	u16 cpu;
656 
657 	this_cpu = smp_processor_id();
658 	cpu_list = __va(tb->cpu_list_pa);
659 	usec_wait = cnt * MONDO_USEC_WAIT_MIN;
660 	if (usec_wait > MONDO_USEC_WAIT_MAX)
661 		usec_wait = MONDO_USEC_WAIT_MAX;
662 	retries = tot_retries = 0;
663 	tot_cpus = cnt;
664 	prev_sent = 0;
665 
666 	do {
667 		int n_sent, mondo_delivered, target_cpu_busy;
668 
669 		status = sun4v_cpu_mondo_send(cnt,
670 					      tb->cpu_list_pa,
671 					      tb->cpu_mondo_block_pa);
672 
673 		/* HV_EOK means all cpus received the xcall, we're done.  */
674 		if (likely(status == HV_EOK))
675 			goto xcall_done;
676 
677 		/* If not these non-fatal errors, panic */
678 		if (unlikely((status != HV_EWOULDBLOCK) &&
679 			(status != HV_ECPUERROR) &&
680 			(status != HV_ENOCPU)))
681 			goto fatal_errors;
682 
683 		/* First, see if we made any forward progress.
684 		 *
685 		 * Go through the cpu_list, count the target cpus that have
686 		 * received our mondo (n_sent), and those that did not (rem).
687 		 * Re-pack cpu_list with the cpus remain to be retried in the
688 		 * front - this simplifies tracking the truly stalled cpus.
689 		 *
690 		 * The hypervisor indicates successful sends by setting
691 		 * cpu list entries to the value 0xffff.
692 		 *
693 		 * EWOULDBLOCK means some target cpus did not receive the
694 		 * mondo and retry usually helps.
695 		 *
696 		 * ECPUERROR means at least one target cpu is in error state,
697 		 * it's usually safe to skip the faulty cpu and retry.
698 		 *
699 		 * ENOCPU means one of the target cpu doesn't belong to the
700 		 * domain, perhaps offlined which is unexpected, but not
701 		 * fatal and it's okay to skip the offlined cpu.
702 		 */
703 		rem = 0;
704 		n_sent = 0;
705 		for (i = 0; i < cnt; i++) {
706 			cpu = cpu_list[i];
707 			if (likely(cpu == 0xffff)) {
708 				n_sent++;
709 			} else if ((status == HV_ECPUERROR) &&
710 				(sun4v_cpu_state(cpu) == HV_CPU_STATE_ERROR)) {
711 				ecpuerror_id = cpu + 1;
712 			} else if (status == HV_ENOCPU && !cpu_online(cpu)) {
713 				enocpu_id = cpu + 1;
714 			} else {
715 				cpu_list[rem++] = cpu;
716 			}
717 		}
718 
719 		/* No cpu remained, we're done. */
720 		if (rem == 0)
721 			break;
722 
723 		/* Otherwise, update the cpu count for retry. */
724 		cnt = rem;
725 
726 		/* Record the overall number of mondos received by the
727 		 * first of the remaining cpus.
728 		 */
729 		if (first_cpu != cpu_list[0]) {
730 			first_cpu = cpu_list[0];
731 			xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
732 		}
733 
734 		/* Was any mondo delivered successfully? */
735 		mondo_delivered = (n_sent > prev_sent);
736 		prev_sent = n_sent;
737 
738 		/* or, was any target cpu busy processing other mondos? */
739 		target_cpu_busy = (xc_rcvd < CPU_MONDO_COUNTER(first_cpu));
740 		xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
741 
742 		/* Retry count is for no progress. If we're making progress,
743 		 * reset the retry count.
744 		 */
745 		if (likely(mondo_delivered || target_cpu_busy)) {
746 			tot_retries += retries;
747 			retries = 0;
748 		} else if (unlikely(retries > MONDO_RETRY_LIMIT)) {
749 			goto fatal_mondo_timeout;
750 		}
751 
752 		/* Delay a little bit to let other cpus catch up on
753 		 * their cpu mondo queue work.
754 		 */
755 		if (!mondo_delivered)
756 			udelay(usec_wait);
757 
758 		retries++;
759 	} while (1);
760 
761 xcall_done:
762 	if (unlikely(ecpuerror_id > 0)) {
763 		pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) was in error state\n",
764 		       this_cpu, ecpuerror_id - 1);
765 	} else if (unlikely(enocpu_id > 0)) {
766 		pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) does not belong to the domain\n",
767 		       this_cpu, enocpu_id - 1);
768 	}
769 	return;
770 
771 fatal_errors:
772 	/* fatal errors include bad alignment, etc */
773 	pr_crit("CPU[%d]: Args were cnt(%d) cpulist_pa(%lx) mondo_block_pa(%lx)\n",
774 	       this_cpu, tot_cpus, tb->cpu_list_pa, tb->cpu_mondo_block_pa);
775 	panic("Unexpected SUN4V mondo error %lu\n", status);
776 
777 fatal_mondo_timeout:
778 	/* some cpus being non-responsive to the cpu mondo */
779 	pr_crit("CPU[%d]: SUN4V mondo timeout, cpu(%d) made no forward progress after %d retries. Total target cpus(%d).\n",
780 	       this_cpu, first_cpu, (tot_retries + retries), tot_cpus);
781 	panic("SUN4V mondo timeout panic\n");
782 }
783 
784 static void (*xcall_deliver_impl)(struct trap_per_cpu *, int);
785 
786 static void xcall_deliver(u64 data0, u64 data1, u64 data2, const cpumask_t *mask)
787 {
788 	struct trap_per_cpu *tb;
789 	int this_cpu, i, cnt;
790 	unsigned long flags;
791 	u16 *cpu_list;
792 	u64 *mondo;
793 
794 	/* We have to do this whole thing with interrupts fully disabled.
795 	 * Otherwise if we send an xcall from interrupt context it will
796 	 * corrupt both our mondo block and cpu list state.
797 	 *
798 	 * One consequence of this is that we cannot use timeout mechanisms
799 	 * that depend upon interrupts being delivered locally.  So, for
800 	 * example, we cannot sample jiffies and expect it to advance.
801 	 *
802 	 * Fortunately, udelay() uses %stick/%tick so we can use that.
803 	 */
804 	local_irq_save(flags);
805 
806 	this_cpu = smp_processor_id();
807 	tb = &trap_block[this_cpu];
808 
809 	mondo = __va(tb->cpu_mondo_block_pa);
810 	mondo[0] = data0;
811 	mondo[1] = data1;
812 	mondo[2] = data2;
813 	wmb();
814 
815 	cpu_list = __va(tb->cpu_list_pa);
816 
817 	/* Setup the initial cpu list.  */
818 	cnt = 0;
819 	for_each_cpu(i, mask) {
820 		if (i == this_cpu || !cpu_online(i))
821 			continue;
822 		cpu_list[cnt++] = i;
823 	}
824 
825 	if (cnt)
826 		xcall_deliver_impl(tb, cnt);
827 
828 	local_irq_restore(flags);
829 }
830 
831 /* Send cross call to all processors mentioned in MASK_P
832  * except self.  Really, there are only two cases currently,
833  * "cpu_online_mask" and "mm_cpumask(mm)".
834  */
835 static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, const cpumask_t *mask)
836 {
837 	u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
838 
839 	xcall_deliver(data0, data1, data2, mask);
840 }
841 
842 /* Send cross call to all processors except self. */
843 static void smp_cross_call(unsigned long *func, u32 ctx, u64 data1, u64 data2)
844 {
845 	smp_cross_call_masked(func, ctx, data1, data2, cpu_online_mask);
846 }
847 
848 extern unsigned long xcall_sync_tick;
849 
850 static void smp_start_sync_tick_client(int cpu)
851 {
852 	xcall_deliver((u64) &xcall_sync_tick, 0, 0,
853 		      cpumask_of(cpu));
854 }
855 
856 extern unsigned long xcall_call_function;
857 
858 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
859 {
860 	xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
861 }
862 
863 extern unsigned long xcall_call_function_single;
864 
865 void arch_send_call_function_single_ipi(int cpu)
866 {
867 	xcall_deliver((u64) &xcall_call_function_single, 0, 0,
868 		      cpumask_of(cpu));
869 }
870 
871 void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs)
872 {
873 	clear_softint(1 << irq);
874 	irq_enter();
875 	generic_smp_call_function_interrupt();
876 	irq_exit();
877 }
878 
879 void __irq_entry smp_call_function_single_client(int irq, struct pt_regs *regs)
880 {
881 	clear_softint(1 << irq);
882 	irq_enter();
883 	generic_smp_call_function_single_interrupt();
884 	irq_exit();
885 }
886 
887 static void tsb_sync(void *info)
888 {
889 	struct trap_per_cpu *tp = &trap_block[raw_smp_processor_id()];
890 	struct mm_struct *mm = info;
891 
892 	/* It is not valid to test "current->active_mm == mm" here.
893 	 *
894 	 * The value of "current" is not changed atomically with
895 	 * switch_mm().  But that's OK, we just need to check the
896 	 * current cpu's trap block PGD physical address.
897 	 */
898 	if (tp->pgd_paddr == __pa(mm->pgd))
899 		tsb_context_switch(mm);
900 }
901 
902 void smp_tsb_sync(struct mm_struct *mm)
903 {
904 	smp_call_function_many(mm_cpumask(mm), tsb_sync, mm, 1);
905 }
906 
907 extern unsigned long xcall_flush_tlb_mm;
908 extern unsigned long xcall_flush_tlb_page;
909 extern unsigned long xcall_flush_tlb_kernel_range;
910 extern unsigned long xcall_fetch_glob_regs;
911 extern unsigned long xcall_fetch_glob_pmu;
912 extern unsigned long xcall_fetch_glob_pmu_n4;
913 extern unsigned long xcall_receive_signal;
914 extern unsigned long xcall_new_mmu_context_version;
915 #ifdef CONFIG_KGDB
916 extern unsigned long xcall_kgdb_capture;
917 #endif
918 
919 #ifdef DCACHE_ALIASING_POSSIBLE
920 extern unsigned long xcall_flush_dcache_page_cheetah;
921 #endif
922 extern unsigned long xcall_flush_dcache_page_spitfire;
923 
924 static inline void __local_flush_dcache_page(struct page *page)
925 {
926 #ifdef DCACHE_ALIASING_POSSIBLE
927 	__flush_dcache_page(page_address(page),
928 			    ((tlb_type == spitfire) &&
929 			     page_mapping_file(page) != NULL));
930 #else
931 	if (page_mapping_file(page) != NULL &&
932 	    tlb_type == spitfire)
933 		__flush_icache_page(__pa(page_address(page)));
934 #endif
935 }
936 
937 void smp_flush_dcache_page_impl(struct page *page, int cpu)
938 {
939 	int this_cpu;
940 
941 	if (tlb_type == hypervisor)
942 		return;
943 
944 #ifdef CONFIG_DEBUG_DCFLUSH
945 	atomic_inc(&dcpage_flushes);
946 #endif
947 
948 	this_cpu = get_cpu();
949 
950 	if (cpu == this_cpu) {
951 		__local_flush_dcache_page(page);
952 	} else if (cpu_online(cpu)) {
953 		void *pg_addr = page_address(page);
954 		u64 data0 = 0;
955 
956 		if (tlb_type == spitfire) {
957 			data0 = ((u64)&xcall_flush_dcache_page_spitfire);
958 			if (page_mapping_file(page) != NULL)
959 				data0 |= ((u64)1 << 32);
960 		} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
961 #ifdef DCACHE_ALIASING_POSSIBLE
962 			data0 =	((u64)&xcall_flush_dcache_page_cheetah);
963 #endif
964 		}
965 		if (data0) {
966 			xcall_deliver(data0, __pa(pg_addr),
967 				      (u64) pg_addr, cpumask_of(cpu));
968 #ifdef CONFIG_DEBUG_DCFLUSH
969 			atomic_inc(&dcpage_flushes_xcall);
970 #endif
971 		}
972 	}
973 
974 	put_cpu();
975 }
976 
977 void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
978 {
979 	void *pg_addr;
980 	u64 data0;
981 
982 	if (tlb_type == hypervisor)
983 		return;
984 
985 	preempt_disable();
986 
987 #ifdef CONFIG_DEBUG_DCFLUSH
988 	atomic_inc(&dcpage_flushes);
989 #endif
990 	data0 = 0;
991 	pg_addr = page_address(page);
992 	if (tlb_type == spitfire) {
993 		data0 = ((u64)&xcall_flush_dcache_page_spitfire);
994 		if (page_mapping_file(page) != NULL)
995 			data0 |= ((u64)1 << 32);
996 	} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
997 #ifdef DCACHE_ALIASING_POSSIBLE
998 		data0 = ((u64)&xcall_flush_dcache_page_cheetah);
999 #endif
1000 	}
1001 	if (data0) {
1002 		xcall_deliver(data0, __pa(pg_addr),
1003 			      (u64) pg_addr, cpu_online_mask);
1004 #ifdef CONFIG_DEBUG_DCFLUSH
1005 		atomic_inc(&dcpage_flushes_xcall);
1006 #endif
1007 	}
1008 	__local_flush_dcache_page(page);
1009 
1010 	preempt_enable();
1011 }
1012 
1013 #ifdef CONFIG_KGDB
1014 void kgdb_roundup_cpus(void)
1015 {
1016 	smp_cross_call(&xcall_kgdb_capture, 0, 0, 0);
1017 }
1018 #endif
1019 
1020 void smp_fetch_global_regs(void)
1021 {
1022 	smp_cross_call(&xcall_fetch_glob_regs, 0, 0, 0);
1023 }
1024 
1025 void smp_fetch_global_pmu(void)
1026 {
1027 	if (tlb_type == hypervisor &&
1028 	    sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
1029 		smp_cross_call(&xcall_fetch_glob_pmu_n4, 0, 0, 0);
1030 	else
1031 		smp_cross_call(&xcall_fetch_glob_pmu, 0, 0, 0);
1032 }
1033 
1034 /* We know that the window frames of the user have been flushed
1035  * to the stack before we get here because all callers of us
1036  * are flush_tlb_*() routines, and these run after flush_cache_*()
1037  * which performs the flushw.
1038  *
1039  * mm->cpu_vm_mask is a bit mask of which cpus an address
1040  * space has (potentially) executed on, this is the heuristic
1041  * we use to limit cross calls.
1042  */
1043 
1044 /* This currently is only used by the hugetlb arch pre-fault
1045  * hook on UltraSPARC-III+ and later when changing the pagesize
1046  * bits of the context register for an address space.
1047  */
1048 void smp_flush_tlb_mm(struct mm_struct *mm)
1049 {
1050 	u32 ctx = CTX_HWBITS(mm->context);
1051 
1052 	get_cpu();
1053 
1054 	smp_cross_call_masked(&xcall_flush_tlb_mm,
1055 			      ctx, 0, 0,
1056 			      mm_cpumask(mm));
1057 
1058 	__flush_tlb_mm(ctx, SECONDARY_CONTEXT);
1059 
1060 	put_cpu();
1061 }
1062 
1063 struct tlb_pending_info {
1064 	unsigned long ctx;
1065 	unsigned long nr;
1066 	unsigned long *vaddrs;
1067 };
1068 
1069 static void tlb_pending_func(void *info)
1070 {
1071 	struct tlb_pending_info *t = info;
1072 
1073 	__flush_tlb_pending(t->ctx, t->nr, t->vaddrs);
1074 }
1075 
1076 void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
1077 {
1078 	u32 ctx = CTX_HWBITS(mm->context);
1079 	struct tlb_pending_info info;
1080 
1081 	get_cpu();
1082 
1083 	info.ctx = ctx;
1084 	info.nr = nr;
1085 	info.vaddrs = vaddrs;
1086 
1087 	smp_call_function_many(mm_cpumask(mm), tlb_pending_func,
1088 			       &info, 1);
1089 
1090 	__flush_tlb_pending(ctx, nr, vaddrs);
1091 
1092 	put_cpu();
1093 }
1094 
1095 void smp_flush_tlb_page(struct mm_struct *mm, unsigned long vaddr)
1096 {
1097 	unsigned long context = CTX_HWBITS(mm->context);
1098 
1099 	get_cpu();
1100 
1101 	smp_cross_call_masked(&xcall_flush_tlb_page,
1102 			      context, vaddr, 0,
1103 			      mm_cpumask(mm));
1104 
1105 	__flush_tlb_page(context, vaddr);
1106 
1107 	put_cpu();
1108 }
1109 
1110 void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
1111 {
1112 	start &= PAGE_MASK;
1113 	end    = PAGE_ALIGN(end);
1114 	if (start != end) {
1115 		smp_cross_call(&xcall_flush_tlb_kernel_range,
1116 			       0, start, end);
1117 
1118 		__flush_tlb_kernel_range(start, end);
1119 	}
1120 }
1121 
1122 /* CPU capture. */
1123 /* #define CAPTURE_DEBUG */
1124 extern unsigned long xcall_capture;
1125 
1126 static atomic_t smp_capture_depth = ATOMIC_INIT(0);
1127 static atomic_t smp_capture_registry = ATOMIC_INIT(0);
1128 static unsigned long penguins_are_doing_time;
1129 
1130 void smp_capture(void)
1131 {
1132 	int result = atomic_add_return(1, &smp_capture_depth);
1133 
1134 	if (result == 1) {
1135 		int ncpus = num_online_cpus();
1136 
1137 #ifdef CAPTURE_DEBUG
1138 		printk("CPU[%d]: Sending penguins to jail...",
1139 		       smp_processor_id());
1140 #endif
1141 		penguins_are_doing_time = 1;
1142 		atomic_inc(&smp_capture_registry);
1143 		smp_cross_call(&xcall_capture, 0, 0, 0);
1144 		while (atomic_read(&smp_capture_registry) != ncpus)
1145 			rmb();
1146 #ifdef CAPTURE_DEBUG
1147 		printk("done\n");
1148 #endif
1149 	}
1150 }
1151 
1152 void smp_release(void)
1153 {
1154 	if (atomic_dec_and_test(&smp_capture_depth)) {
1155 #ifdef CAPTURE_DEBUG
1156 		printk("CPU[%d]: Giving pardon to "
1157 		       "imprisoned penguins\n",
1158 		       smp_processor_id());
1159 #endif
1160 		penguins_are_doing_time = 0;
1161 		membar_safe("#StoreLoad");
1162 		atomic_dec(&smp_capture_registry);
1163 	}
1164 }
1165 
1166 /* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE
1167  * set, so they can service tlb flush xcalls...
1168  */
1169 extern void prom_world(int);
1170 
1171 void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs)
1172 {
1173 	clear_softint(1 << irq);
1174 
1175 	preempt_disable();
1176 
1177 	__asm__ __volatile__("flushw");
1178 	prom_world(1);
1179 	atomic_inc(&smp_capture_registry);
1180 	membar_safe("#StoreLoad");
1181 	while (penguins_are_doing_time)
1182 		rmb();
1183 	atomic_dec(&smp_capture_registry);
1184 	prom_world(0);
1185 
1186 	preempt_enable();
1187 }
1188 
1189 void __init smp_prepare_cpus(unsigned int max_cpus)
1190 {
1191 }
1192 
1193 void smp_prepare_boot_cpu(void)
1194 {
1195 }
1196 
1197 void __init smp_setup_processor_id(void)
1198 {
1199 	if (tlb_type == spitfire)
1200 		xcall_deliver_impl = spitfire_xcall_deliver;
1201 	else if (tlb_type == cheetah || tlb_type == cheetah_plus)
1202 		xcall_deliver_impl = cheetah_xcall_deliver;
1203 	else
1204 		xcall_deliver_impl = hypervisor_xcall_deliver;
1205 }
1206 
1207 void __init smp_fill_in_cpu_possible_map(void)
1208 {
1209 	int possible_cpus = num_possible_cpus();
1210 	int i;
1211 
1212 	if (possible_cpus > nr_cpu_ids)
1213 		possible_cpus = nr_cpu_ids;
1214 
1215 	for (i = 0; i < possible_cpus; i++)
1216 		set_cpu_possible(i, true);
1217 	for (; i < NR_CPUS; i++)
1218 		set_cpu_possible(i, false);
1219 }
1220 
1221 void smp_fill_in_sib_core_maps(void)
1222 {
1223 	unsigned int i;
1224 
1225 	for_each_present_cpu(i) {
1226 		unsigned int j;
1227 
1228 		cpumask_clear(&cpu_core_map[i]);
1229 		if (cpu_data(i).core_id == 0) {
1230 			cpumask_set_cpu(i, &cpu_core_map[i]);
1231 			continue;
1232 		}
1233 
1234 		for_each_present_cpu(j) {
1235 			if (cpu_data(i).core_id ==
1236 			    cpu_data(j).core_id)
1237 				cpumask_set_cpu(j, &cpu_core_map[i]);
1238 		}
1239 	}
1240 
1241 	for_each_present_cpu(i)  {
1242 		unsigned int j;
1243 
1244 		for_each_present_cpu(j)  {
1245 			if (cpu_data(i).max_cache_id ==
1246 			    cpu_data(j).max_cache_id)
1247 				cpumask_set_cpu(j, &cpu_core_sib_cache_map[i]);
1248 
1249 			if (cpu_data(i).sock_id == cpu_data(j).sock_id)
1250 				cpumask_set_cpu(j, &cpu_core_sib_map[i]);
1251 		}
1252 	}
1253 
1254 	for_each_present_cpu(i) {
1255 		unsigned int j;
1256 
1257 		cpumask_clear(&per_cpu(cpu_sibling_map, i));
1258 		if (cpu_data(i).proc_id == -1) {
1259 			cpumask_set_cpu(i, &per_cpu(cpu_sibling_map, i));
1260 			continue;
1261 		}
1262 
1263 		for_each_present_cpu(j) {
1264 			if (cpu_data(i).proc_id ==
1265 			    cpu_data(j).proc_id)
1266 				cpumask_set_cpu(j, &per_cpu(cpu_sibling_map, i));
1267 		}
1268 	}
1269 }
1270 
1271 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
1272 {
1273 	int ret = smp_boot_one_cpu(cpu, tidle);
1274 
1275 	if (!ret) {
1276 		cpumask_set_cpu(cpu, &smp_commenced_mask);
1277 		while (!cpu_online(cpu))
1278 			mb();
1279 		if (!cpu_online(cpu)) {
1280 			ret = -ENODEV;
1281 		} else {
1282 			/* On SUN4V, writes to %tick and %stick are
1283 			 * not allowed.
1284 			 */
1285 			if (tlb_type != hypervisor)
1286 				smp_synchronize_one_tick(cpu);
1287 		}
1288 	}
1289 	return ret;
1290 }
1291 
1292 #ifdef CONFIG_HOTPLUG_CPU
1293 void cpu_play_dead(void)
1294 {
1295 	int cpu = smp_processor_id();
1296 	unsigned long pstate;
1297 
1298 	idle_task_exit();
1299 
1300 	if (tlb_type == hypervisor) {
1301 		struct trap_per_cpu *tb = &trap_block[cpu];
1302 
1303 		sun4v_cpu_qconf(HV_CPU_QUEUE_CPU_MONDO,
1304 				tb->cpu_mondo_pa, 0);
1305 		sun4v_cpu_qconf(HV_CPU_QUEUE_DEVICE_MONDO,
1306 				tb->dev_mondo_pa, 0);
1307 		sun4v_cpu_qconf(HV_CPU_QUEUE_RES_ERROR,
1308 				tb->resum_mondo_pa, 0);
1309 		sun4v_cpu_qconf(HV_CPU_QUEUE_NONRES_ERROR,
1310 				tb->nonresum_mondo_pa, 0);
1311 	}
1312 
1313 	cpumask_clear_cpu(cpu, &smp_commenced_mask);
1314 	membar_safe("#Sync");
1315 
1316 	local_irq_disable();
1317 
1318 	__asm__ __volatile__(
1319 		"rdpr	%%pstate, %0\n\t"
1320 		"wrpr	%0, %1, %%pstate"
1321 		: "=r" (pstate)
1322 		: "i" (PSTATE_IE));
1323 
1324 	while (1)
1325 		barrier();
1326 }
1327 
1328 int __cpu_disable(void)
1329 {
1330 	int cpu = smp_processor_id();
1331 	cpuinfo_sparc *c;
1332 	int i;
1333 
1334 	for_each_cpu(i, &cpu_core_map[cpu])
1335 		cpumask_clear_cpu(cpu, &cpu_core_map[i]);
1336 	cpumask_clear(&cpu_core_map[cpu]);
1337 
1338 	for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu))
1339 		cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i));
1340 	cpumask_clear(&per_cpu(cpu_sibling_map, cpu));
1341 
1342 	c = &cpu_data(cpu);
1343 
1344 	c->core_id = 0;
1345 	c->proc_id = -1;
1346 
1347 	smp_wmb();
1348 
1349 	/* Make sure no interrupts point to this cpu.  */
1350 	fixup_irqs();
1351 
1352 	local_irq_enable();
1353 	mdelay(1);
1354 	local_irq_disable();
1355 
1356 	set_cpu_online(cpu, false);
1357 
1358 	cpu_map_rebuild();
1359 
1360 	return 0;
1361 }
1362 
1363 void __cpu_die(unsigned int cpu)
1364 {
1365 	int i;
1366 
1367 	for (i = 0; i < 100; i++) {
1368 		smp_rmb();
1369 		if (!cpumask_test_cpu(cpu, &smp_commenced_mask))
1370 			break;
1371 		msleep(100);
1372 	}
1373 	if (cpumask_test_cpu(cpu, &smp_commenced_mask)) {
1374 		printk(KERN_ERR "CPU %u didn't die...\n", cpu);
1375 	} else {
1376 #if defined(CONFIG_SUN_LDOMS)
1377 		unsigned long hv_err;
1378 		int limit = 100;
1379 
1380 		do {
1381 			hv_err = sun4v_cpu_stop(cpu);
1382 			if (hv_err == HV_EOK) {
1383 				set_cpu_present(cpu, false);
1384 				break;
1385 			}
1386 		} while (--limit > 0);
1387 		if (limit <= 0) {
1388 			printk(KERN_ERR "sun4v_cpu_stop() fails err=%lu\n",
1389 			       hv_err);
1390 		}
1391 #endif
1392 	}
1393 }
1394 #endif
1395 
1396 void __init smp_cpus_done(unsigned int max_cpus)
1397 {
1398 }
1399 
1400 static void send_cpu_ipi(int cpu)
1401 {
1402 	xcall_deliver((u64) &xcall_receive_signal,
1403 			0, 0, cpumask_of(cpu));
1404 }
1405 
1406 void scheduler_poke(void)
1407 {
1408 	if (!cpu_poke)
1409 		return;
1410 
1411 	if (!__this_cpu_read(poke))
1412 		return;
1413 
1414 	__this_cpu_write(poke, false);
1415 	set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1416 }
1417 
1418 static unsigned long send_cpu_poke(int cpu)
1419 {
1420 	unsigned long hv_err;
1421 
1422 	per_cpu(poke, cpu) = true;
1423 	hv_err = sun4v_cpu_poke(cpu);
1424 	if (hv_err != HV_EOK) {
1425 		per_cpu(poke, cpu) = false;
1426 		pr_err_ratelimited("%s: sun4v_cpu_poke() fails err=%lu\n",
1427 				    __func__, hv_err);
1428 	}
1429 
1430 	return hv_err;
1431 }
1432 
1433 void arch_smp_send_reschedule(int cpu)
1434 {
1435 	if (cpu == smp_processor_id()) {
1436 		WARN_ON_ONCE(preemptible());
1437 		set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1438 		return;
1439 	}
1440 
1441 	/* Use cpu poke to resume idle cpu if supported. */
1442 	if (cpu_poke && idle_cpu(cpu)) {
1443 		unsigned long ret;
1444 
1445 		ret = send_cpu_poke(cpu);
1446 		if (ret == HV_EOK)
1447 			return;
1448 	}
1449 
1450 	/* Use IPI in following cases:
1451 	 * - cpu poke not supported
1452 	 * - cpu not idle
1453 	 * - send_cpu_poke() returns with error
1454 	 */
1455 	send_cpu_ipi(cpu);
1456 }
1457 
1458 void smp_init_cpu_poke(void)
1459 {
1460 	unsigned long major;
1461 	unsigned long minor;
1462 	int ret;
1463 
1464 	if (tlb_type != hypervisor)
1465 		return;
1466 
1467 	ret = sun4v_hvapi_get(HV_GRP_CORE, &major, &minor);
1468 	if (ret) {
1469 		pr_debug("HV_GRP_CORE is not registered\n");
1470 		return;
1471 	}
1472 
1473 	if (major == 1 && minor >= 6) {
1474 		/* CPU POKE is registered. */
1475 		cpu_poke = true;
1476 		return;
1477 	}
1478 
1479 	pr_debug("CPU_POKE not supported\n");
1480 }
1481 
1482 void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs)
1483 {
1484 	clear_softint(1 << irq);
1485 	scheduler_ipi();
1486 }
1487 
1488 static void stop_this_cpu(void *dummy)
1489 {
1490 	set_cpu_online(smp_processor_id(), false);
1491 	prom_stopself();
1492 }
1493 
1494 void smp_send_stop(void)
1495 {
1496 	int cpu;
1497 
1498 	if (tlb_type == hypervisor) {
1499 		int this_cpu = smp_processor_id();
1500 #ifdef CONFIG_SERIAL_SUNHV
1501 		sunhv_migrate_hvcons_irq(this_cpu);
1502 #endif
1503 		for_each_online_cpu(cpu) {
1504 			if (cpu == this_cpu)
1505 				continue;
1506 
1507 			set_cpu_online(cpu, false);
1508 #ifdef CONFIG_SUN_LDOMS
1509 			if (ldom_domaining_enabled) {
1510 				unsigned long hv_err;
1511 				hv_err = sun4v_cpu_stop(cpu);
1512 				if (hv_err)
1513 					printk(KERN_ERR "sun4v_cpu_stop() "
1514 					       "failed err=%lu\n", hv_err);
1515 			} else
1516 #endif
1517 				prom_stopcpu_cpuid(cpu);
1518 		}
1519 	} else
1520 		smp_call_function(stop_this_cpu, NULL, 0);
1521 }
1522 
1523 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
1524 {
1525 	if (cpu_to_node(from) == cpu_to_node(to))
1526 		return LOCAL_DISTANCE;
1527 	else
1528 		return REMOTE_DISTANCE;
1529 }
1530 
1531 static int __init pcpu_cpu_to_node(int cpu)
1532 {
1533 	return cpu_to_node(cpu);
1534 }
1535 
1536 void __init setup_per_cpu_areas(void)
1537 {
1538 	unsigned long delta;
1539 	unsigned int cpu;
1540 	int rc = -EINVAL;
1541 
1542 	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
1543 		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
1544 					    PERCPU_DYNAMIC_RESERVE, 4 << 20,
1545 					    pcpu_cpu_distance,
1546 					    pcpu_cpu_to_node);
1547 		if (rc)
1548 			pr_warn("PERCPU: %s allocator failed (%d), "
1549 				"falling back to page size\n",
1550 				pcpu_fc_names[pcpu_chosen_fc], rc);
1551 	}
1552 	if (rc < 0)
1553 		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
1554 					   pcpu_cpu_to_node);
1555 	if (rc < 0)
1556 		panic("cannot initialize percpu area (err=%d)", rc);
1557 
1558 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
1559 	for_each_possible_cpu(cpu)
1560 		__per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];
1561 
1562 	/* Setup %g5 for the boot cpu.  */
1563 	__local_per_cpu_offset = __per_cpu_offset(smp_processor_id());
1564 
1565 	of_fill_in_cpu_data();
1566 	if (tlb_type == hypervisor)
1567 		mdesc_fill_in_cpu_data(cpu_all_mask);
1568 }
1569