xref: /openbmc/linux/arch/sparc/kernel/smp_64.c (revision 842ed298)
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 	/* idle thread is expected to have preempt disabled */
142 	preempt_disable();
143 
144 	local_irq_enable();
145 
146 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
147 }
148 
149 void cpu_panic(void)
150 {
151 	printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
152 	panic("SMP bolixed\n");
153 }
154 
155 /* This tick register synchronization scheme is taken entirely from
156  * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
157  *
158  * The only change I've made is to rework it so that the master
159  * initiates the synchonization instead of the slave. -DaveM
160  */
161 
162 #define MASTER	0
163 #define SLAVE	(SMP_CACHE_BYTES/sizeof(unsigned long))
164 
165 #define NUM_ROUNDS	64	/* magic value */
166 #define NUM_ITERS	5	/* likewise */
167 
168 static DEFINE_RAW_SPINLOCK(itc_sync_lock);
169 static unsigned long go[SLAVE + 1];
170 
171 #define DEBUG_TICK_SYNC	0
172 
173 static inline long get_delta (long *rt, long *master)
174 {
175 	unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
176 	unsigned long tcenter, t0, t1, tm;
177 	unsigned long i;
178 
179 	for (i = 0; i < NUM_ITERS; i++) {
180 		t0 = tick_ops->get_tick();
181 		go[MASTER] = 1;
182 		membar_safe("#StoreLoad");
183 		while (!(tm = go[SLAVE]))
184 			rmb();
185 		go[SLAVE] = 0;
186 		wmb();
187 		t1 = tick_ops->get_tick();
188 
189 		if (t1 - t0 < best_t1 - best_t0)
190 			best_t0 = t0, best_t1 = t1, best_tm = tm;
191 	}
192 
193 	*rt = best_t1 - best_t0;
194 	*master = best_tm - best_t0;
195 
196 	/* average best_t0 and best_t1 without overflow: */
197 	tcenter = (best_t0/2 + best_t1/2);
198 	if (best_t0 % 2 + best_t1 % 2 == 2)
199 		tcenter++;
200 	return tcenter - best_tm;
201 }
202 
203 void smp_synchronize_tick_client(void)
204 {
205 	long i, delta, adj, adjust_latency = 0, done = 0;
206 	unsigned long flags, rt, master_time_stamp;
207 #if DEBUG_TICK_SYNC
208 	struct {
209 		long rt;	/* roundtrip time */
210 		long master;	/* master's timestamp */
211 		long diff;	/* difference between midpoint and master's timestamp */
212 		long lat;	/* estimate of itc adjustment latency */
213 	} t[NUM_ROUNDS];
214 #endif
215 
216 	go[MASTER] = 1;
217 
218 	while (go[MASTER])
219 		rmb();
220 
221 	local_irq_save(flags);
222 	{
223 		for (i = 0; i < NUM_ROUNDS; i++) {
224 			delta = get_delta(&rt, &master_time_stamp);
225 			if (delta == 0)
226 				done = 1;	/* let's lock on to this... */
227 
228 			if (!done) {
229 				if (i > 0) {
230 					adjust_latency += -delta;
231 					adj = -delta + adjust_latency/4;
232 				} else
233 					adj = -delta;
234 
235 				tick_ops->add_tick(adj);
236 			}
237 #if DEBUG_TICK_SYNC
238 			t[i].rt = rt;
239 			t[i].master = master_time_stamp;
240 			t[i].diff = delta;
241 			t[i].lat = adjust_latency/4;
242 #endif
243 		}
244 	}
245 	local_irq_restore(flags);
246 
247 #if DEBUG_TICK_SYNC
248 	for (i = 0; i < NUM_ROUNDS; i++)
249 		printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
250 		       t[i].rt, t[i].master, t[i].diff, t[i].lat);
251 #endif
252 
253 	printk(KERN_INFO "CPU %d: synchronized TICK with master CPU "
254 	       "(last diff %ld cycles, maxerr %lu cycles)\n",
255 	       smp_processor_id(), delta, rt);
256 }
257 
258 static void smp_start_sync_tick_client(int cpu);
259 
260 static void smp_synchronize_one_tick(int cpu)
261 {
262 	unsigned long flags, i;
263 
264 	go[MASTER] = 0;
265 
266 	smp_start_sync_tick_client(cpu);
267 
268 	/* wait for client to be ready */
269 	while (!go[MASTER])
270 		rmb();
271 
272 	/* now let the client proceed into his loop */
273 	go[MASTER] = 0;
274 	membar_safe("#StoreLoad");
275 
276 	raw_spin_lock_irqsave(&itc_sync_lock, flags);
277 	{
278 		for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
279 			while (!go[MASTER])
280 				rmb();
281 			go[MASTER] = 0;
282 			wmb();
283 			go[SLAVE] = tick_ops->get_tick();
284 			membar_safe("#StoreLoad");
285 		}
286 	}
287 	raw_spin_unlock_irqrestore(&itc_sync_lock, flags);
288 }
289 
290 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
291 static void ldom_startcpu_cpuid(unsigned int cpu, unsigned long thread_reg,
292 				void **descrp)
293 {
294 	extern unsigned long sparc64_ttable_tl0;
295 	extern unsigned long kern_locked_tte_data;
296 	struct hvtramp_descr *hdesc;
297 	unsigned long trampoline_ra;
298 	struct trap_per_cpu *tb;
299 	u64 tte_vaddr, tte_data;
300 	unsigned long hv_err;
301 	int i;
302 
303 	hdesc = kzalloc(sizeof(*hdesc) +
304 			(sizeof(struct hvtramp_mapping) *
305 			 num_kernel_image_mappings - 1),
306 			GFP_KERNEL);
307 	if (!hdesc) {
308 		printk(KERN_ERR "ldom_startcpu_cpuid: Cannot allocate "
309 		       "hvtramp_descr.\n");
310 		return;
311 	}
312 	*descrp = hdesc;
313 
314 	hdesc->cpu = cpu;
315 	hdesc->num_mappings = num_kernel_image_mappings;
316 
317 	tb = &trap_block[cpu];
318 
319 	hdesc->fault_info_va = (unsigned long) &tb->fault_info;
320 	hdesc->fault_info_pa = kimage_addr_to_ra(&tb->fault_info);
321 
322 	hdesc->thread_reg = thread_reg;
323 
324 	tte_vaddr = (unsigned long) KERNBASE;
325 	tte_data = kern_locked_tte_data;
326 
327 	for (i = 0; i < hdesc->num_mappings; i++) {
328 		hdesc->maps[i].vaddr = tte_vaddr;
329 		hdesc->maps[i].tte   = tte_data;
330 		tte_vaddr += 0x400000;
331 		tte_data  += 0x400000;
332 	}
333 
334 	trampoline_ra = kimage_addr_to_ra(hv_cpu_startup);
335 
336 	hv_err = sun4v_cpu_start(cpu, trampoline_ra,
337 				 kimage_addr_to_ra(&sparc64_ttable_tl0),
338 				 __pa(hdesc));
339 	if (hv_err)
340 		printk(KERN_ERR "ldom_startcpu_cpuid: sun4v_cpu_start() "
341 		       "gives error %lu\n", hv_err);
342 }
343 #endif
344 
345 extern unsigned long sparc64_cpu_startup;
346 
347 /* The OBP cpu startup callback truncates the 3rd arg cookie to
348  * 32-bits (I think) so to be safe we have it read the pointer
349  * contained here so we work on >4GB machines. -DaveM
350  */
351 static struct thread_info *cpu_new_thread = NULL;
352 
353 static int smp_boot_one_cpu(unsigned int cpu, struct task_struct *idle)
354 {
355 	unsigned long entry =
356 		(unsigned long)(&sparc64_cpu_startup);
357 	unsigned long cookie =
358 		(unsigned long)(&cpu_new_thread);
359 	void *descr = NULL;
360 	int timeout, ret;
361 
362 	callin_flag = 0;
363 	cpu_new_thread = task_thread_info(idle);
364 
365 	if (tlb_type == hypervisor) {
366 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
367 		if (ldom_domaining_enabled)
368 			ldom_startcpu_cpuid(cpu,
369 					    (unsigned long) cpu_new_thread,
370 					    &descr);
371 		else
372 #endif
373 			prom_startcpu_cpuid(cpu, entry, cookie);
374 	} else {
375 		struct device_node *dp = of_find_node_by_cpuid(cpu);
376 
377 		prom_startcpu(dp->phandle, entry, cookie);
378 	}
379 
380 	for (timeout = 0; timeout < 50000; timeout++) {
381 		if (callin_flag)
382 			break;
383 		udelay(100);
384 	}
385 
386 	if (callin_flag) {
387 		ret = 0;
388 	} else {
389 		printk("Processor %d is stuck.\n", cpu);
390 		ret = -ENODEV;
391 	}
392 	cpu_new_thread = NULL;
393 
394 	kfree(descr);
395 
396 	return ret;
397 }
398 
399 static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
400 {
401 	u64 result, target;
402 	int stuck, tmp;
403 
404 	if (this_is_starfire) {
405 		/* map to real upaid */
406 		cpu = (((cpu & 0x3c) << 1) |
407 			((cpu & 0x40) >> 4) |
408 			(cpu & 0x3));
409 	}
410 
411 	target = (cpu << 14) | 0x70;
412 again:
413 	/* Ok, this is the real Spitfire Errata #54.
414 	 * One must read back from a UDB internal register
415 	 * after writes to the UDB interrupt dispatch, but
416 	 * before the membar Sync for that write.
417 	 * So we use the high UDB control register (ASI 0x7f,
418 	 * ADDR 0x20) for the dummy read. -DaveM
419 	 */
420 	tmp = 0x40;
421 	__asm__ __volatile__(
422 	"wrpr	%1, %2, %%pstate\n\t"
423 	"stxa	%4, [%0] %3\n\t"
424 	"stxa	%5, [%0+%8] %3\n\t"
425 	"add	%0, %8, %0\n\t"
426 	"stxa	%6, [%0+%8] %3\n\t"
427 	"membar	#Sync\n\t"
428 	"stxa	%%g0, [%7] %3\n\t"
429 	"membar	#Sync\n\t"
430 	"mov	0x20, %%g1\n\t"
431 	"ldxa	[%%g1] 0x7f, %%g0\n\t"
432 	"membar	#Sync"
433 	: "=r" (tmp)
434 	: "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
435 	  "r" (data0), "r" (data1), "r" (data2), "r" (target),
436 	  "r" (0x10), "0" (tmp)
437         : "g1");
438 
439 	/* NOTE: PSTATE_IE is still clear. */
440 	stuck = 100000;
441 	do {
442 		__asm__ __volatile__("ldxa [%%g0] %1, %0"
443 			: "=r" (result)
444 			: "i" (ASI_INTR_DISPATCH_STAT));
445 		if (result == 0) {
446 			__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
447 					     : : "r" (pstate));
448 			return;
449 		}
450 		stuck -= 1;
451 		if (stuck == 0)
452 			break;
453 	} while (result & 0x1);
454 	__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
455 			     : : "r" (pstate));
456 	if (stuck == 0) {
457 		printk("CPU[%d]: mondo stuckage result[%016llx]\n",
458 		       smp_processor_id(), result);
459 	} else {
460 		udelay(2);
461 		goto again;
462 	}
463 }
464 
465 static void spitfire_xcall_deliver(struct trap_per_cpu *tb, int cnt)
466 {
467 	u64 *mondo, data0, data1, data2;
468 	u16 *cpu_list;
469 	u64 pstate;
470 	int i;
471 
472 	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
473 	cpu_list = __va(tb->cpu_list_pa);
474 	mondo = __va(tb->cpu_mondo_block_pa);
475 	data0 = mondo[0];
476 	data1 = mondo[1];
477 	data2 = mondo[2];
478 	for (i = 0; i < cnt; i++)
479 		spitfire_xcall_helper(data0, data1, data2, pstate, cpu_list[i]);
480 }
481 
482 /* Cheetah now allows to send the whole 64-bytes of data in the interrupt
483  * packet, but we have no use for that.  However we do take advantage of
484  * the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
485  */
486 static void cheetah_xcall_deliver(struct trap_per_cpu *tb, int cnt)
487 {
488 	int nack_busy_id, is_jbus, need_more;
489 	u64 *mondo, pstate, ver, busy_mask;
490 	u16 *cpu_list;
491 
492 	cpu_list = __va(tb->cpu_list_pa);
493 	mondo = __va(tb->cpu_mondo_block_pa);
494 
495 	/* Unfortunately, someone at Sun had the brilliant idea to make the
496 	 * busy/nack fields hard-coded by ITID number for this Ultra-III
497 	 * derivative processor.
498 	 */
499 	__asm__ ("rdpr %%ver, %0" : "=r" (ver));
500 	is_jbus = ((ver >> 32) == __JALAPENO_ID ||
501 		   (ver >> 32) == __SERRANO_ID);
502 
503 	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
504 
505 retry:
506 	need_more = 0;
507 	__asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
508 			     : : "r" (pstate), "i" (PSTATE_IE));
509 
510 	/* Setup the dispatch data registers. */
511 	__asm__ __volatile__("stxa	%0, [%3] %6\n\t"
512 			     "stxa	%1, [%4] %6\n\t"
513 			     "stxa	%2, [%5] %6\n\t"
514 			     "membar	#Sync\n\t"
515 			     : /* no outputs */
516 			     : "r" (mondo[0]), "r" (mondo[1]), "r" (mondo[2]),
517 			       "r" (0x40), "r" (0x50), "r" (0x60),
518 			       "i" (ASI_INTR_W));
519 
520 	nack_busy_id = 0;
521 	busy_mask = 0;
522 	{
523 		int i;
524 
525 		for (i = 0; i < cnt; i++) {
526 			u64 target, nr;
527 
528 			nr = cpu_list[i];
529 			if (nr == 0xffff)
530 				continue;
531 
532 			target = (nr << 14) | 0x70;
533 			if (is_jbus) {
534 				busy_mask |= (0x1UL << (nr * 2));
535 			} else {
536 				target |= (nack_busy_id << 24);
537 				busy_mask |= (0x1UL <<
538 					      (nack_busy_id * 2));
539 			}
540 			__asm__ __volatile__(
541 				"stxa	%%g0, [%0] %1\n\t"
542 				"membar	#Sync\n\t"
543 				: /* no outputs */
544 				: "r" (target), "i" (ASI_INTR_W));
545 			nack_busy_id++;
546 			if (nack_busy_id == 32) {
547 				need_more = 1;
548 				break;
549 			}
550 		}
551 	}
552 
553 	/* Now, poll for completion. */
554 	{
555 		u64 dispatch_stat, nack_mask;
556 		long stuck;
557 
558 		stuck = 100000 * nack_busy_id;
559 		nack_mask = busy_mask << 1;
560 		do {
561 			__asm__ __volatile__("ldxa	[%%g0] %1, %0"
562 					     : "=r" (dispatch_stat)
563 					     : "i" (ASI_INTR_DISPATCH_STAT));
564 			if (!(dispatch_stat & (busy_mask | nack_mask))) {
565 				__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
566 						     : : "r" (pstate));
567 				if (unlikely(need_more)) {
568 					int i, this_cnt = 0;
569 					for (i = 0; i < cnt; i++) {
570 						if (cpu_list[i] == 0xffff)
571 							continue;
572 						cpu_list[i] = 0xffff;
573 						this_cnt++;
574 						if (this_cnt == 32)
575 							break;
576 					}
577 					goto retry;
578 				}
579 				return;
580 			}
581 			if (!--stuck)
582 				break;
583 		} while (dispatch_stat & busy_mask);
584 
585 		__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
586 				     : : "r" (pstate));
587 
588 		if (dispatch_stat & busy_mask) {
589 			/* Busy bits will not clear, continue instead
590 			 * of freezing up on this cpu.
591 			 */
592 			printk("CPU[%d]: mondo stuckage result[%016llx]\n",
593 			       smp_processor_id(), dispatch_stat);
594 		} else {
595 			int i, this_busy_nack = 0;
596 
597 			/* Delay some random time with interrupts enabled
598 			 * to prevent deadlock.
599 			 */
600 			udelay(2 * nack_busy_id);
601 
602 			/* Clear out the mask bits for cpus which did not
603 			 * NACK us.
604 			 */
605 			for (i = 0; i < cnt; i++) {
606 				u64 check_mask, nr;
607 
608 				nr = cpu_list[i];
609 				if (nr == 0xffff)
610 					continue;
611 
612 				if (is_jbus)
613 					check_mask = (0x2UL << (2*nr));
614 				else
615 					check_mask = (0x2UL <<
616 						      this_busy_nack);
617 				if ((dispatch_stat & check_mask) == 0)
618 					cpu_list[i] = 0xffff;
619 				this_busy_nack += 2;
620 				if (this_busy_nack == 64)
621 					break;
622 			}
623 
624 			goto retry;
625 		}
626 	}
627 }
628 
629 #define	CPU_MONDO_COUNTER(cpuid)	(cpu_mondo_counter[cpuid])
630 #define	MONDO_USEC_WAIT_MIN		2
631 #define	MONDO_USEC_WAIT_MAX		100
632 #define	MONDO_RETRY_LIMIT		500000
633 
634 /* Multi-cpu list version.
635  *
636  * Deliver xcalls to 'cnt' number of cpus in 'cpu_list'.
637  * Sometimes not all cpus receive the mondo, requiring us to re-send
638  * the mondo until all cpus have received, or cpus are truly stuck
639  * unable to receive mondo, and we timeout.
640  * Occasionally a target cpu strand is borrowed briefly by hypervisor to
641  * perform guest service, such as PCIe error handling. Consider the
642  * service time, 1 second overall wait is reasonable for 1 cpu.
643  * Here two in-between mondo check wait time are defined: 2 usec for
644  * single cpu quick turn around and up to 100usec for large cpu count.
645  * Deliver mondo to large number of cpus could take longer, we adjusts
646  * the retry count as long as target cpus are making forward progress.
647  */
648 static void hypervisor_xcall_deliver(struct trap_per_cpu *tb, int cnt)
649 {
650 	int this_cpu, tot_cpus, prev_sent, i, rem;
651 	int usec_wait, retries, tot_retries;
652 	u16 first_cpu = 0xffff;
653 	unsigned long xc_rcvd = 0;
654 	unsigned long status;
655 	int ecpuerror_id = 0;
656 	int enocpu_id = 0;
657 	u16 *cpu_list;
658 	u16 cpu;
659 
660 	this_cpu = smp_processor_id();
661 	cpu_list = __va(tb->cpu_list_pa);
662 	usec_wait = cnt * MONDO_USEC_WAIT_MIN;
663 	if (usec_wait > MONDO_USEC_WAIT_MAX)
664 		usec_wait = MONDO_USEC_WAIT_MAX;
665 	retries = tot_retries = 0;
666 	tot_cpus = cnt;
667 	prev_sent = 0;
668 
669 	do {
670 		int n_sent, mondo_delivered, target_cpu_busy;
671 
672 		status = sun4v_cpu_mondo_send(cnt,
673 					      tb->cpu_list_pa,
674 					      tb->cpu_mondo_block_pa);
675 
676 		/* HV_EOK means all cpus received the xcall, we're done.  */
677 		if (likely(status == HV_EOK))
678 			goto xcall_done;
679 
680 		/* If not these non-fatal errors, panic */
681 		if (unlikely((status != HV_EWOULDBLOCK) &&
682 			(status != HV_ECPUERROR) &&
683 			(status != HV_ENOCPU)))
684 			goto fatal_errors;
685 
686 		/* First, see if we made any forward progress.
687 		 *
688 		 * Go through the cpu_list, count the target cpus that have
689 		 * received our mondo (n_sent), and those that did not (rem).
690 		 * Re-pack cpu_list with the cpus remain to be retried in the
691 		 * front - this simplifies tracking the truly stalled cpus.
692 		 *
693 		 * The hypervisor indicates successful sends by setting
694 		 * cpu list entries to the value 0xffff.
695 		 *
696 		 * EWOULDBLOCK means some target cpus did not receive the
697 		 * mondo and retry usually helps.
698 		 *
699 		 * ECPUERROR means at least one target cpu is in error state,
700 		 * it's usually safe to skip the faulty cpu and retry.
701 		 *
702 		 * ENOCPU means one of the target cpu doesn't belong to the
703 		 * domain, perhaps offlined which is unexpected, but not
704 		 * fatal and it's okay to skip the offlined cpu.
705 		 */
706 		rem = 0;
707 		n_sent = 0;
708 		for (i = 0; i < cnt; i++) {
709 			cpu = cpu_list[i];
710 			if (likely(cpu == 0xffff)) {
711 				n_sent++;
712 			} else if ((status == HV_ECPUERROR) &&
713 				(sun4v_cpu_state(cpu) == HV_CPU_STATE_ERROR)) {
714 				ecpuerror_id = cpu + 1;
715 			} else if (status == HV_ENOCPU && !cpu_online(cpu)) {
716 				enocpu_id = cpu + 1;
717 			} else {
718 				cpu_list[rem++] = cpu;
719 			}
720 		}
721 
722 		/* No cpu remained, we're done. */
723 		if (rem == 0)
724 			break;
725 
726 		/* Otherwise, update the cpu count for retry. */
727 		cnt = rem;
728 
729 		/* Record the overall number of mondos received by the
730 		 * first of the remaining cpus.
731 		 */
732 		if (first_cpu != cpu_list[0]) {
733 			first_cpu = cpu_list[0];
734 			xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
735 		}
736 
737 		/* Was any mondo delivered successfully? */
738 		mondo_delivered = (n_sent > prev_sent);
739 		prev_sent = n_sent;
740 
741 		/* or, was any target cpu busy processing other mondos? */
742 		target_cpu_busy = (xc_rcvd < CPU_MONDO_COUNTER(first_cpu));
743 		xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
744 
745 		/* Retry count is for no progress. If we're making progress,
746 		 * reset the retry count.
747 		 */
748 		if (likely(mondo_delivered || target_cpu_busy)) {
749 			tot_retries += retries;
750 			retries = 0;
751 		} else if (unlikely(retries > MONDO_RETRY_LIMIT)) {
752 			goto fatal_mondo_timeout;
753 		}
754 
755 		/* Delay a little bit to let other cpus catch up on
756 		 * their cpu mondo queue work.
757 		 */
758 		if (!mondo_delivered)
759 			udelay(usec_wait);
760 
761 		retries++;
762 	} while (1);
763 
764 xcall_done:
765 	if (unlikely(ecpuerror_id > 0)) {
766 		pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) was in error state\n",
767 		       this_cpu, ecpuerror_id - 1);
768 	} else if (unlikely(enocpu_id > 0)) {
769 		pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) does not belong to the domain\n",
770 		       this_cpu, enocpu_id - 1);
771 	}
772 	return;
773 
774 fatal_errors:
775 	/* fatal errors include bad alignment, etc */
776 	pr_crit("CPU[%d]: Args were cnt(%d) cpulist_pa(%lx) mondo_block_pa(%lx)\n",
777 	       this_cpu, tot_cpus, tb->cpu_list_pa, tb->cpu_mondo_block_pa);
778 	panic("Unexpected SUN4V mondo error %lu\n", status);
779 
780 fatal_mondo_timeout:
781 	/* some cpus being non-responsive to the cpu mondo */
782 	pr_crit("CPU[%d]: SUN4V mondo timeout, cpu(%d) made no forward progress after %d retries. Total target cpus(%d).\n",
783 	       this_cpu, first_cpu, (tot_retries + retries), tot_cpus);
784 	panic("SUN4V mondo timeout panic\n");
785 }
786 
787 static void (*xcall_deliver_impl)(struct trap_per_cpu *, int);
788 
789 static void xcall_deliver(u64 data0, u64 data1, u64 data2, const cpumask_t *mask)
790 {
791 	struct trap_per_cpu *tb;
792 	int this_cpu, i, cnt;
793 	unsigned long flags;
794 	u16 *cpu_list;
795 	u64 *mondo;
796 
797 	/* We have to do this whole thing with interrupts fully disabled.
798 	 * Otherwise if we send an xcall from interrupt context it will
799 	 * corrupt both our mondo block and cpu list state.
800 	 *
801 	 * One consequence of this is that we cannot use timeout mechanisms
802 	 * that depend upon interrupts being delivered locally.  So, for
803 	 * example, we cannot sample jiffies and expect it to advance.
804 	 *
805 	 * Fortunately, udelay() uses %stick/%tick so we can use that.
806 	 */
807 	local_irq_save(flags);
808 
809 	this_cpu = smp_processor_id();
810 	tb = &trap_block[this_cpu];
811 
812 	mondo = __va(tb->cpu_mondo_block_pa);
813 	mondo[0] = data0;
814 	mondo[1] = data1;
815 	mondo[2] = data2;
816 	wmb();
817 
818 	cpu_list = __va(tb->cpu_list_pa);
819 
820 	/* Setup the initial cpu list.  */
821 	cnt = 0;
822 	for_each_cpu(i, mask) {
823 		if (i == this_cpu || !cpu_online(i))
824 			continue;
825 		cpu_list[cnt++] = i;
826 	}
827 
828 	if (cnt)
829 		xcall_deliver_impl(tb, cnt);
830 
831 	local_irq_restore(flags);
832 }
833 
834 /* Send cross call to all processors mentioned in MASK_P
835  * except self.  Really, there are only two cases currently,
836  * "cpu_online_mask" and "mm_cpumask(mm)".
837  */
838 static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, const cpumask_t *mask)
839 {
840 	u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
841 
842 	xcall_deliver(data0, data1, data2, mask);
843 }
844 
845 /* Send cross call to all processors except self. */
846 static void smp_cross_call(unsigned long *func, u32 ctx, u64 data1, u64 data2)
847 {
848 	smp_cross_call_masked(func, ctx, data1, data2, cpu_online_mask);
849 }
850 
851 extern unsigned long xcall_sync_tick;
852 
853 static void smp_start_sync_tick_client(int cpu)
854 {
855 	xcall_deliver((u64) &xcall_sync_tick, 0, 0,
856 		      cpumask_of(cpu));
857 }
858 
859 extern unsigned long xcall_call_function;
860 
861 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
862 {
863 	xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
864 }
865 
866 extern unsigned long xcall_call_function_single;
867 
868 void arch_send_call_function_single_ipi(int cpu)
869 {
870 	xcall_deliver((u64) &xcall_call_function_single, 0, 0,
871 		      cpumask_of(cpu));
872 }
873 
874 void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs)
875 {
876 	clear_softint(1 << irq);
877 	irq_enter();
878 	generic_smp_call_function_interrupt();
879 	irq_exit();
880 }
881 
882 void __irq_entry smp_call_function_single_client(int irq, struct pt_regs *regs)
883 {
884 	clear_softint(1 << irq);
885 	irq_enter();
886 	generic_smp_call_function_single_interrupt();
887 	irq_exit();
888 }
889 
890 static void tsb_sync(void *info)
891 {
892 	struct trap_per_cpu *tp = &trap_block[raw_smp_processor_id()];
893 	struct mm_struct *mm = info;
894 
895 	/* It is not valid to test "current->active_mm == mm" here.
896 	 *
897 	 * The value of "current" is not changed atomically with
898 	 * switch_mm().  But that's OK, we just need to check the
899 	 * current cpu's trap block PGD physical address.
900 	 */
901 	if (tp->pgd_paddr == __pa(mm->pgd))
902 		tsb_context_switch(mm);
903 }
904 
905 void smp_tsb_sync(struct mm_struct *mm)
906 {
907 	smp_call_function_many(mm_cpumask(mm), tsb_sync, mm, 1);
908 }
909 
910 extern unsigned long xcall_flush_tlb_mm;
911 extern unsigned long xcall_flush_tlb_page;
912 extern unsigned long xcall_flush_tlb_kernel_range;
913 extern unsigned long xcall_fetch_glob_regs;
914 extern unsigned long xcall_fetch_glob_pmu;
915 extern unsigned long xcall_fetch_glob_pmu_n4;
916 extern unsigned long xcall_receive_signal;
917 extern unsigned long xcall_new_mmu_context_version;
918 #ifdef CONFIG_KGDB
919 extern unsigned long xcall_kgdb_capture;
920 #endif
921 
922 #ifdef DCACHE_ALIASING_POSSIBLE
923 extern unsigned long xcall_flush_dcache_page_cheetah;
924 #endif
925 extern unsigned long xcall_flush_dcache_page_spitfire;
926 
927 static inline void __local_flush_dcache_page(struct page *page)
928 {
929 #ifdef DCACHE_ALIASING_POSSIBLE
930 	__flush_dcache_page(page_address(page),
931 			    ((tlb_type == spitfire) &&
932 			     page_mapping_file(page) != NULL));
933 #else
934 	if (page_mapping_file(page) != NULL &&
935 	    tlb_type == spitfire)
936 		__flush_icache_page(__pa(page_address(page)));
937 #endif
938 }
939 
940 void smp_flush_dcache_page_impl(struct page *page, int cpu)
941 {
942 	int this_cpu;
943 
944 	if (tlb_type == hypervisor)
945 		return;
946 
947 #ifdef CONFIG_DEBUG_DCFLUSH
948 	atomic_inc(&dcpage_flushes);
949 #endif
950 
951 	this_cpu = get_cpu();
952 
953 	if (cpu == this_cpu) {
954 		__local_flush_dcache_page(page);
955 	} else if (cpu_online(cpu)) {
956 		void *pg_addr = page_address(page);
957 		u64 data0 = 0;
958 
959 		if (tlb_type == spitfire) {
960 			data0 = ((u64)&xcall_flush_dcache_page_spitfire);
961 			if (page_mapping_file(page) != NULL)
962 				data0 |= ((u64)1 << 32);
963 		} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
964 #ifdef DCACHE_ALIASING_POSSIBLE
965 			data0 =	((u64)&xcall_flush_dcache_page_cheetah);
966 #endif
967 		}
968 		if (data0) {
969 			xcall_deliver(data0, __pa(pg_addr),
970 				      (u64) pg_addr, cpumask_of(cpu));
971 #ifdef CONFIG_DEBUG_DCFLUSH
972 			atomic_inc(&dcpage_flushes_xcall);
973 #endif
974 		}
975 	}
976 
977 	put_cpu();
978 }
979 
980 void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
981 {
982 	void *pg_addr;
983 	u64 data0;
984 
985 	if (tlb_type == hypervisor)
986 		return;
987 
988 	preempt_disable();
989 
990 #ifdef CONFIG_DEBUG_DCFLUSH
991 	atomic_inc(&dcpage_flushes);
992 #endif
993 	data0 = 0;
994 	pg_addr = page_address(page);
995 	if (tlb_type == spitfire) {
996 		data0 = ((u64)&xcall_flush_dcache_page_spitfire);
997 		if (page_mapping_file(page) != NULL)
998 			data0 |= ((u64)1 << 32);
999 	} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
1000 #ifdef DCACHE_ALIASING_POSSIBLE
1001 		data0 = ((u64)&xcall_flush_dcache_page_cheetah);
1002 #endif
1003 	}
1004 	if (data0) {
1005 		xcall_deliver(data0, __pa(pg_addr),
1006 			      (u64) pg_addr, cpu_online_mask);
1007 #ifdef CONFIG_DEBUG_DCFLUSH
1008 		atomic_inc(&dcpage_flushes_xcall);
1009 #endif
1010 	}
1011 	__local_flush_dcache_page(page);
1012 
1013 	preempt_enable();
1014 }
1015 
1016 #ifdef CONFIG_KGDB
1017 void kgdb_roundup_cpus(void)
1018 {
1019 	smp_cross_call(&xcall_kgdb_capture, 0, 0, 0);
1020 }
1021 #endif
1022 
1023 void smp_fetch_global_regs(void)
1024 {
1025 	smp_cross_call(&xcall_fetch_glob_regs, 0, 0, 0);
1026 }
1027 
1028 void smp_fetch_global_pmu(void)
1029 {
1030 	if (tlb_type == hypervisor &&
1031 	    sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
1032 		smp_cross_call(&xcall_fetch_glob_pmu_n4, 0, 0, 0);
1033 	else
1034 		smp_cross_call(&xcall_fetch_glob_pmu, 0, 0, 0);
1035 }
1036 
1037 /* We know that the window frames of the user have been flushed
1038  * to the stack before we get here because all callers of us
1039  * are flush_tlb_*() routines, and these run after flush_cache_*()
1040  * which performs the flushw.
1041  *
1042  * mm->cpu_vm_mask is a bit mask of which cpus an address
1043  * space has (potentially) executed on, this is the heuristic
1044  * we use to limit cross calls.
1045  */
1046 
1047 /* This currently is only used by the hugetlb arch pre-fault
1048  * hook on UltraSPARC-III+ and later when changing the pagesize
1049  * bits of the context register for an address space.
1050  */
1051 void smp_flush_tlb_mm(struct mm_struct *mm)
1052 {
1053 	u32 ctx = CTX_HWBITS(mm->context);
1054 
1055 	get_cpu();
1056 
1057 	smp_cross_call_masked(&xcall_flush_tlb_mm,
1058 			      ctx, 0, 0,
1059 			      mm_cpumask(mm));
1060 
1061 	__flush_tlb_mm(ctx, SECONDARY_CONTEXT);
1062 
1063 	put_cpu();
1064 }
1065 
1066 struct tlb_pending_info {
1067 	unsigned long ctx;
1068 	unsigned long nr;
1069 	unsigned long *vaddrs;
1070 };
1071 
1072 static void tlb_pending_func(void *info)
1073 {
1074 	struct tlb_pending_info *t = info;
1075 
1076 	__flush_tlb_pending(t->ctx, t->nr, t->vaddrs);
1077 }
1078 
1079 void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
1080 {
1081 	u32 ctx = CTX_HWBITS(mm->context);
1082 	struct tlb_pending_info info;
1083 
1084 	get_cpu();
1085 
1086 	info.ctx = ctx;
1087 	info.nr = nr;
1088 	info.vaddrs = vaddrs;
1089 
1090 	smp_call_function_many(mm_cpumask(mm), tlb_pending_func,
1091 			       &info, 1);
1092 
1093 	__flush_tlb_pending(ctx, nr, vaddrs);
1094 
1095 	put_cpu();
1096 }
1097 
1098 void smp_flush_tlb_page(struct mm_struct *mm, unsigned long vaddr)
1099 {
1100 	unsigned long context = CTX_HWBITS(mm->context);
1101 
1102 	get_cpu();
1103 
1104 	smp_cross_call_masked(&xcall_flush_tlb_page,
1105 			      context, vaddr, 0,
1106 			      mm_cpumask(mm));
1107 
1108 	__flush_tlb_page(context, vaddr);
1109 
1110 	put_cpu();
1111 }
1112 
1113 void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
1114 {
1115 	start &= PAGE_MASK;
1116 	end    = PAGE_ALIGN(end);
1117 	if (start != end) {
1118 		smp_cross_call(&xcall_flush_tlb_kernel_range,
1119 			       0, start, end);
1120 
1121 		__flush_tlb_kernel_range(start, end);
1122 	}
1123 }
1124 
1125 /* CPU capture. */
1126 /* #define CAPTURE_DEBUG */
1127 extern unsigned long xcall_capture;
1128 
1129 static atomic_t smp_capture_depth = ATOMIC_INIT(0);
1130 static atomic_t smp_capture_registry = ATOMIC_INIT(0);
1131 static unsigned long penguins_are_doing_time;
1132 
1133 void smp_capture(void)
1134 {
1135 	int result = atomic_add_return(1, &smp_capture_depth);
1136 
1137 	if (result == 1) {
1138 		int ncpus = num_online_cpus();
1139 
1140 #ifdef CAPTURE_DEBUG
1141 		printk("CPU[%d]: Sending penguins to jail...",
1142 		       smp_processor_id());
1143 #endif
1144 		penguins_are_doing_time = 1;
1145 		atomic_inc(&smp_capture_registry);
1146 		smp_cross_call(&xcall_capture, 0, 0, 0);
1147 		while (atomic_read(&smp_capture_registry) != ncpus)
1148 			rmb();
1149 #ifdef CAPTURE_DEBUG
1150 		printk("done\n");
1151 #endif
1152 	}
1153 }
1154 
1155 void smp_release(void)
1156 {
1157 	if (atomic_dec_and_test(&smp_capture_depth)) {
1158 #ifdef CAPTURE_DEBUG
1159 		printk("CPU[%d]: Giving pardon to "
1160 		       "imprisoned penguins\n",
1161 		       smp_processor_id());
1162 #endif
1163 		penguins_are_doing_time = 0;
1164 		membar_safe("#StoreLoad");
1165 		atomic_dec(&smp_capture_registry);
1166 	}
1167 }
1168 
1169 /* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE
1170  * set, so they can service tlb flush xcalls...
1171  */
1172 extern void prom_world(int);
1173 
1174 void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs)
1175 {
1176 	clear_softint(1 << irq);
1177 
1178 	preempt_disable();
1179 
1180 	__asm__ __volatile__("flushw");
1181 	prom_world(1);
1182 	atomic_inc(&smp_capture_registry);
1183 	membar_safe("#StoreLoad");
1184 	while (penguins_are_doing_time)
1185 		rmb();
1186 	atomic_dec(&smp_capture_registry);
1187 	prom_world(0);
1188 
1189 	preempt_enable();
1190 }
1191 
1192 /* /proc/profile writes can call this, don't __init it please. */
1193 int setup_profiling_timer(unsigned int multiplier)
1194 {
1195 	return -EINVAL;
1196 }
1197 
1198 void __init smp_prepare_cpus(unsigned int max_cpus)
1199 {
1200 }
1201 
1202 void smp_prepare_boot_cpu(void)
1203 {
1204 }
1205 
1206 void __init smp_setup_processor_id(void)
1207 {
1208 	if (tlb_type == spitfire)
1209 		xcall_deliver_impl = spitfire_xcall_deliver;
1210 	else if (tlb_type == cheetah || tlb_type == cheetah_plus)
1211 		xcall_deliver_impl = cheetah_xcall_deliver;
1212 	else
1213 		xcall_deliver_impl = hypervisor_xcall_deliver;
1214 }
1215 
1216 void __init smp_fill_in_cpu_possible_map(void)
1217 {
1218 	int possible_cpus = num_possible_cpus();
1219 	int i;
1220 
1221 	if (possible_cpus > nr_cpu_ids)
1222 		possible_cpus = nr_cpu_ids;
1223 
1224 	for (i = 0; i < possible_cpus; i++)
1225 		set_cpu_possible(i, true);
1226 	for (; i < NR_CPUS; i++)
1227 		set_cpu_possible(i, false);
1228 }
1229 
1230 void smp_fill_in_sib_core_maps(void)
1231 {
1232 	unsigned int i;
1233 
1234 	for_each_present_cpu(i) {
1235 		unsigned int j;
1236 
1237 		cpumask_clear(&cpu_core_map[i]);
1238 		if (cpu_data(i).core_id == 0) {
1239 			cpumask_set_cpu(i, &cpu_core_map[i]);
1240 			continue;
1241 		}
1242 
1243 		for_each_present_cpu(j) {
1244 			if (cpu_data(i).core_id ==
1245 			    cpu_data(j).core_id)
1246 				cpumask_set_cpu(j, &cpu_core_map[i]);
1247 		}
1248 	}
1249 
1250 	for_each_present_cpu(i)  {
1251 		unsigned int j;
1252 
1253 		for_each_present_cpu(j)  {
1254 			if (cpu_data(i).max_cache_id ==
1255 			    cpu_data(j).max_cache_id)
1256 				cpumask_set_cpu(j, &cpu_core_sib_cache_map[i]);
1257 
1258 			if (cpu_data(i).sock_id == cpu_data(j).sock_id)
1259 				cpumask_set_cpu(j, &cpu_core_sib_map[i]);
1260 		}
1261 	}
1262 
1263 	for_each_present_cpu(i) {
1264 		unsigned int j;
1265 
1266 		cpumask_clear(&per_cpu(cpu_sibling_map, i));
1267 		if (cpu_data(i).proc_id == -1) {
1268 			cpumask_set_cpu(i, &per_cpu(cpu_sibling_map, i));
1269 			continue;
1270 		}
1271 
1272 		for_each_present_cpu(j) {
1273 			if (cpu_data(i).proc_id ==
1274 			    cpu_data(j).proc_id)
1275 				cpumask_set_cpu(j, &per_cpu(cpu_sibling_map, i));
1276 		}
1277 	}
1278 }
1279 
1280 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
1281 {
1282 	int ret = smp_boot_one_cpu(cpu, tidle);
1283 
1284 	if (!ret) {
1285 		cpumask_set_cpu(cpu, &smp_commenced_mask);
1286 		while (!cpu_online(cpu))
1287 			mb();
1288 		if (!cpu_online(cpu)) {
1289 			ret = -ENODEV;
1290 		} else {
1291 			/* On SUN4V, writes to %tick and %stick are
1292 			 * not allowed.
1293 			 */
1294 			if (tlb_type != hypervisor)
1295 				smp_synchronize_one_tick(cpu);
1296 		}
1297 	}
1298 	return ret;
1299 }
1300 
1301 #ifdef CONFIG_HOTPLUG_CPU
1302 void cpu_play_dead(void)
1303 {
1304 	int cpu = smp_processor_id();
1305 	unsigned long pstate;
1306 
1307 	idle_task_exit();
1308 
1309 	if (tlb_type == hypervisor) {
1310 		struct trap_per_cpu *tb = &trap_block[cpu];
1311 
1312 		sun4v_cpu_qconf(HV_CPU_QUEUE_CPU_MONDO,
1313 				tb->cpu_mondo_pa, 0);
1314 		sun4v_cpu_qconf(HV_CPU_QUEUE_DEVICE_MONDO,
1315 				tb->dev_mondo_pa, 0);
1316 		sun4v_cpu_qconf(HV_CPU_QUEUE_RES_ERROR,
1317 				tb->resum_mondo_pa, 0);
1318 		sun4v_cpu_qconf(HV_CPU_QUEUE_NONRES_ERROR,
1319 				tb->nonresum_mondo_pa, 0);
1320 	}
1321 
1322 	cpumask_clear_cpu(cpu, &smp_commenced_mask);
1323 	membar_safe("#Sync");
1324 
1325 	local_irq_disable();
1326 
1327 	__asm__ __volatile__(
1328 		"rdpr	%%pstate, %0\n\t"
1329 		"wrpr	%0, %1, %%pstate"
1330 		: "=r" (pstate)
1331 		: "i" (PSTATE_IE));
1332 
1333 	while (1)
1334 		barrier();
1335 }
1336 
1337 int __cpu_disable(void)
1338 {
1339 	int cpu = smp_processor_id();
1340 	cpuinfo_sparc *c;
1341 	int i;
1342 
1343 	for_each_cpu(i, &cpu_core_map[cpu])
1344 		cpumask_clear_cpu(cpu, &cpu_core_map[i]);
1345 	cpumask_clear(&cpu_core_map[cpu]);
1346 
1347 	for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu))
1348 		cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i));
1349 	cpumask_clear(&per_cpu(cpu_sibling_map, cpu));
1350 
1351 	c = &cpu_data(cpu);
1352 
1353 	c->core_id = 0;
1354 	c->proc_id = -1;
1355 
1356 	smp_wmb();
1357 
1358 	/* Make sure no interrupts point to this cpu.  */
1359 	fixup_irqs();
1360 
1361 	local_irq_enable();
1362 	mdelay(1);
1363 	local_irq_disable();
1364 
1365 	set_cpu_online(cpu, false);
1366 
1367 	cpu_map_rebuild();
1368 
1369 	return 0;
1370 }
1371 
1372 void __cpu_die(unsigned int cpu)
1373 {
1374 	int i;
1375 
1376 	for (i = 0; i < 100; i++) {
1377 		smp_rmb();
1378 		if (!cpumask_test_cpu(cpu, &smp_commenced_mask))
1379 			break;
1380 		msleep(100);
1381 	}
1382 	if (cpumask_test_cpu(cpu, &smp_commenced_mask)) {
1383 		printk(KERN_ERR "CPU %u didn't die...\n", cpu);
1384 	} else {
1385 #if defined(CONFIG_SUN_LDOMS)
1386 		unsigned long hv_err;
1387 		int limit = 100;
1388 
1389 		do {
1390 			hv_err = sun4v_cpu_stop(cpu);
1391 			if (hv_err == HV_EOK) {
1392 				set_cpu_present(cpu, false);
1393 				break;
1394 			}
1395 		} while (--limit > 0);
1396 		if (limit <= 0) {
1397 			printk(KERN_ERR "sun4v_cpu_stop() fails err=%lu\n",
1398 			       hv_err);
1399 		}
1400 #endif
1401 	}
1402 }
1403 #endif
1404 
1405 void __init smp_cpus_done(unsigned int max_cpus)
1406 {
1407 }
1408 
1409 static void send_cpu_ipi(int cpu)
1410 {
1411 	xcall_deliver((u64) &xcall_receive_signal,
1412 			0, 0, cpumask_of(cpu));
1413 }
1414 
1415 void scheduler_poke(void)
1416 {
1417 	if (!cpu_poke)
1418 		return;
1419 
1420 	if (!__this_cpu_read(poke))
1421 		return;
1422 
1423 	__this_cpu_write(poke, false);
1424 	set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1425 }
1426 
1427 static unsigned long send_cpu_poke(int cpu)
1428 {
1429 	unsigned long hv_err;
1430 
1431 	per_cpu(poke, cpu) = true;
1432 	hv_err = sun4v_cpu_poke(cpu);
1433 	if (hv_err != HV_EOK) {
1434 		per_cpu(poke, cpu) = false;
1435 		pr_err_ratelimited("%s: sun4v_cpu_poke() fails err=%lu\n",
1436 				    __func__, hv_err);
1437 	}
1438 
1439 	return hv_err;
1440 }
1441 
1442 void smp_send_reschedule(int cpu)
1443 {
1444 	if (cpu == smp_processor_id()) {
1445 		WARN_ON_ONCE(preemptible());
1446 		set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1447 		return;
1448 	}
1449 
1450 	/* Use cpu poke to resume idle cpu if supported. */
1451 	if (cpu_poke && idle_cpu(cpu)) {
1452 		unsigned long ret;
1453 
1454 		ret = send_cpu_poke(cpu);
1455 		if (ret == HV_EOK)
1456 			return;
1457 	}
1458 
1459 	/* Use IPI in following cases:
1460 	 * - cpu poke not supported
1461 	 * - cpu not idle
1462 	 * - send_cpu_poke() returns with error
1463 	 */
1464 	send_cpu_ipi(cpu);
1465 }
1466 
1467 void smp_init_cpu_poke(void)
1468 {
1469 	unsigned long major;
1470 	unsigned long minor;
1471 	int ret;
1472 
1473 	if (tlb_type != hypervisor)
1474 		return;
1475 
1476 	ret = sun4v_hvapi_get(HV_GRP_CORE, &major, &minor);
1477 	if (ret) {
1478 		pr_debug("HV_GRP_CORE is not registered\n");
1479 		return;
1480 	}
1481 
1482 	if (major == 1 && minor >= 6) {
1483 		/* CPU POKE is registered. */
1484 		cpu_poke = true;
1485 		return;
1486 	}
1487 
1488 	pr_debug("CPU_POKE not supported\n");
1489 }
1490 
1491 void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs)
1492 {
1493 	clear_softint(1 << irq);
1494 	scheduler_ipi();
1495 }
1496 
1497 static void stop_this_cpu(void *dummy)
1498 {
1499 	set_cpu_online(smp_processor_id(), false);
1500 	prom_stopself();
1501 }
1502 
1503 void smp_send_stop(void)
1504 {
1505 	int cpu;
1506 
1507 	if (tlb_type == hypervisor) {
1508 		int this_cpu = smp_processor_id();
1509 #ifdef CONFIG_SERIAL_SUNHV
1510 		sunhv_migrate_hvcons_irq(this_cpu);
1511 #endif
1512 		for_each_online_cpu(cpu) {
1513 			if (cpu == this_cpu)
1514 				continue;
1515 
1516 			set_cpu_online(cpu, false);
1517 #ifdef CONFIG_SUN_LDOMS
1518 			if (ldom_domaining_enabled) {
1519 				unsigned long hv_err;
1520 				hv_err = sun4v_cpu_stop(cpu);
1521 				if (hv_err)
1522 					printk(KERN_ERR "sun4v_cpu_stop() "
1523 					       "failed err=%lu\n", hv_err);
1524 			} else
1525 #endif
1526 				prom_stopcpu_cpuid(cpu);
1527 		}
1528 	} else
1529 		smp_call_function(stop_this_cpu, NULL, 0);
1530 }
1531 
1532 /**
1533  * pcpu_alloc_bootmem - NUMA friendly alloc_bootmem wrapper for percpu
1534  * @cpu: cpu to allocate for
1535  * @size: size allocation in bytes
1536  * @align: alignment
1537  *
1538  * Allocate @size bytes aligned at @align for cpu @cpu.  This wrapper
1539  * does the right thing for NUMA regardless of the current
1540  * configuration.
1541  *
1542  * RETURNS:
1543  * Pointer to the allocated area on success, NULL on failure.
1544  */
1545 static void * __init pcpu_alloc_bootmem(unsigned int cpu, size_t size,
1546 					size_t align)
1547 {
1548 	const unsigned long goal = __pa(MAX_DMA_ADDRESS);
1549 #ifdef CONFIG_NEED_MULTIPLE_NODES
1550 	int node = cpu_to_node(cpu);
1551 	void *ptr;
1552 
1553 	if (!node_online(node) || !NODE_DATA(node)) {
1554 		ptr = memblock_alloc_from(size, align, goal);
1555 		pr_info("cpu %d has no node %d or node-local memory\n",
1556 			cpu, node);
1557 		pr_debug("per cpu data for cpu%d %lu bytes at %016lx\n",
1558 			 cpu, size, __pa(ptr));
1559 	} else {
1560 		ptr = memblock_alloc_try_nid(size, align, goal,
1561 					     MEMBLOCK_ALLOC_ACCESSIBLE, node);
1562 		pr_debug("per cpu data for cpu%d %lu bytes on node%d at "
1563 			 "%016lx\n", cpu, size, node, __pa(ptr));
1564 	}
1565 	return ptr;
1566 #else
1567 	return memblock_alloc_from(size, align, goal);
1568 #endif
1569 }
1570 
1571 static void __init pcpu_free_bootmem(void *ptr, size_t size)
1572 {
1573 	memblock_free(__pa(ptr), size);
1574 }
1575 
1576 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
1577 {
1578 	if (cpu_to_node(from) == cpu_to_node(to))
1579 		return LOCAL_DISTANCE;
1580 	else
1581 		return REMOTE_DISTANCE;
1582 }
1583 
1584 static void __init pcpu_populate_pte(unsigned long addr)
1585 {
1586 	pgd_t *pgd = pgd_offset_k(addr);
1587 	p4d_t *p4d;
1588 	pud_t *pud;
1589 	pmd_t *pmd;
1590 
1591 	if (pgd_none(*pgd)) {
1592 		pud_t *new;
1593 
1594 		new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1595 		if (!new)
1596 			goto err_alloc;
1597 		pgd_populate(&init_mm, pgd, new);
1598 	}
1599 
1600 	p4d = p4d_offset(pgd, addr);
1601 	if (p4d_none(*p4d)) {
1602 		pud_t *new;
1603 
1604 		new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1605 		if (!new)
1606 			goto err_alloc;
1607 		p4d_populate(&init_mm, p4d, new);
1608 	}
1609 
1610 	pud = pud_offset(p4d, addr);
1611 	if (pud_none(*pud)) {
1612 		pmd_t *new;
1613 
1614 		new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1615 		if (!new)
1616 			goto err_alloc;
1617 		pud_populate(&init_mm, pud, new);
1618 	}
1619 
1620 	pmd = pmd_offset(pud, addr);
1621 	if (!pmd_present(*pmd)) {
1622 		pte_t *new;
1623 
1624 		new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1625 		if (!new)
1626 			goto err_alloc;
1627 		pmd_populate_kernel(&init_mm, pmd, new);
1628 	}
1629 
1630 	return;
1631 
1632 err_alloc:
1633 	panic("%s: Failed to allocate %lu bytes align=%lx from=%lx\n",
1634 	      __func__, PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1635 }
1636 
1637 void __init setup_per_cpu_areas(void)
1638 {
1639 	unsigned long delta;
1640 	unsigned int cpu;
1641 	int rc = -EINVAL;
1642 
1643 	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
1644 		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
1645 					    PERCPU_DYNAMIC_RESERVE, 4 << 20,
1646 					    pcpu_cpu_distance,
1647 					    pcpu_alloc_bootmem,
1648 					    pcpu_free_bootmem);
1649 		if (rc)
1650 			pr_warn("PERCPU: %s allocator failed (%d), "
1651 				"falling back to page size\n",
1652 				pcpu_fc_names[pcpu_chosen_fc], rc);
1653 	}
1654 	if (rc < 0)
1655 		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
1656 					   pcpu_alloc_bootmem,
1657 					   pcpu_free_bootmem,
1658 					   pcpu_populate_pte);
1659 	if (rc < 0)
1660 		panic("cannot initialize percpu area (err=%d)", rc);
1661 
1662 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
1663 	for_each_possible_cpu(cpu)
1664 		__per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];
1665 
1666 	/* Setup %g5 for the boot cpu.  */
1667 	__local_per_cpu_offset = __per_cpu_offset(smp_processor_id());
1668 
1669 	of_fill_in_cpu_data();
1670 	if (tlb_type == hypervisor)
1671 		mdesc_fill_in_cpu_data(cpu_all_mask);
1672 }
1673