xref: /linux/arch/sparc/kernel/smp_64.c (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
1 /* smp.c: Sparc64 SMP support.
2  *
3  * Copyright (C) 1997, 2007, 2008 David S. Miller (davem@davemloft.net)
4  */
5 
6 #include <linux/export.h>
7 #include <linux/kernel.h>
8 #include <linux/sched.h>
9 #include <linux/mm.h>
10 #include <linux/pagemap.h>
11 #include <linux/threads.h>
12 #include <linux/smp.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel_stat.h>
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/spinlock.h>
18 #include <linux/fs.h>
19 #include <linux/seq_file.h>
20 #include <linux/cache.h>
21 #include <linux/jiffies.h>
22 #include <linux/profile.h>
23 #include <linux/bootmem.h>
24 #include <linux/vmalloc.h>
25 #include <linux/ftrace.h>
26 #include <linux/cpu.h>
27 #include <linux/slab.h>
28 
29 #include <asm/head.h>
30 #include <asm/ptrace.h>
31 #include <linux/atomic.h>
32 #include <asm/tlbflush.h>
33 #include <asm/mmu_context.h>
34 #include <asm/cpudata.h>
35 #include <asm/hvtramp.h>
36 #include <asm/io.h>
37 #include <asm/timer.h>
38 
39 #include <asm/irq.h>
40 #include <asm/irq_regs.h>
41 #include <asm/page.h>
42 #include <asm/pgtable.h>
43 #include <asm/oplib.h>
44 #include <asm/uaccess.h>
45 #include <asm/starfire.h>
46 #include <asm/tlb.h>
47 #include <asm/sections.h>
48 #include <asm/prom.h>
49 #include <asm/mdesc.h>
50 #include <asm/ldc.h>
51 #include <asm/hypervisor.h>
52 #include <asm/pcr.h>
53 
54 #include "cpumap.h"
55 
56 int sparc64_multi_core __read_mostly;
57 
58 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
59 cpumask_t cpu_core_map[NR_CPUS] __read_mostly =
60 	{ [0 ... NR_CPUS-1] = CPU_MASK_NONE };
61 
62 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
63 EXPORT_SYMBOL(cpu_core_map);
64 
65 static cpumask_t smp_commenced_mask;
66 
67 void smp_info(struct seq_file *m)
68 {
69 	int i;
70 
71 	seq_printf(m, "State:\n");
72 	for_each_online_cpu(i)
73 		seq_printf(m, "CPU%d:\t\tonline\n", i);
74 }
75 
76 void smp_bogo(struct seq_file *m)
77 {
78 	int i;
79 
80 	for_each_online_cpu(i)
81 		seq_printf(m,
82 			   "Cpu%dClkTck\t: %016lx\n",
83 			   i, cpu_data(i).clock_tick);
84 }
85 
86 extern void setup_sparc64_timer(void);
87 
88 static volatile unsigned long callin_flag = 0;
89 
90 void __cpuinit smp_callin(void)
91 {
92 	int cpuid = hard_smp_processor_id();
93 
94 	__local_per_cpu_offset = __per_cpu_offset(cpuid);
95 
96 	if (tlb_type == hypervisor)
97 		sun4v_ktsb_register();
98 
99 	__flush_tlb_all();
100 
101 	setup_sparc64_timer();
102 
103 	if (cheetah_pcache_forced_on)
104 		cheetah_enable_pcache();
105 
106 	local_irq_enable();
107 
108 	callin_flag = 1;
109 	__asm__ __volatile__("membar #Sync\n\t"
110 			     "flush  %%g6" : : : "memory");
111 
112 	/* Clear this or we will die instantly when we
113 	 * schedule back to this idler...
114 	 */
115 	current_thread_info()->new_child = 0;
116 
117 	/* Attach to the address space of init_task. */
118 	atomic_inc(&init_mm.mm_count);
119 	current->active_mm = &init_mm;
120 
121 	/* inform the notifiers about the new cpu */
122 	notify_cpu_starting(cpuid);
123 
124 	while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
125 		rmb();
126 
127 	ipi_call_lock_irq();
128 	set_cpu_online(cpuid, true);
129 	ipi_call_unlock_irq();
130 
131 	/* idle thread is expected to have preempt disabled */
132 	preempt_disable();
133 }
134 
135 void cpu_panic(void)
136 {
137 	printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
138 	panic("SMP bolixed\n");
139 }
140 
141 /* This tick register synchronization scheme is taken entirely from
142  * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
143  *
144  * The only change I've made is to rework it so that the master
145  * initiates the synchonization instead of the slave. -DaveM
146  */
147 
148 #define MASTER	0
149 #define SLAVE	(SMP_CACHE_BYTES/sizeof(unsigned long))
150 
151 #define NUM_ROUNDS	64	/* magic value */
152 #define NUM_ITERS	5	/* likewise */
153 
154 static DEFINE_SPINLOCK(itc_sync_lock);
155 static unsigned long go[SLAVE + 1];
156 
157 #define DEBUG_TICK_SYNC	0
158 
159 static inline long get_delta (long *rt, long *master)
160 {
161 	unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
162 	unsigned long tcenter, t0, t1, tm;
163 	unsigned long i;
164 
165 	for (i = 0; i < NUM_ITERS; i++) {
166 		t0 = tick_ops->get_tick();
167 		go[MASTER] = 1;
168 		membar_safe("#StoreLoad");
169 		while (!(tm = go[SLAVE]))
170 			rmb();
171 		go[SLAVE] = 0;
172 		wmb();
173 		t1 = tick_ops->get_tick();
174 
175 		if (t1 - t0 < best_t1 - best_t0)
176 			best_t0 = t0, best_t1 = t1, best_tm = tm;
177 	}
178 
179 	*rt = best_t1 - best_t0;
180 	*master = best_tm - best_t0;
181 
182 	/* average best_t0 and best_t1 without overflow: */
183 	tcenter = (best_t0/2 + best_t1/2);
184 	if (best_t0 % 2 + best_t1 % 2 == 2)
185 		tcenter++;
186 	return tcenter - best_tm;
187 }
188 
189 void smp_synchronize_tick_client(void)
190 {
191 	long i, delta, adj, adjust_latency = 0, done = 0;
192 	unsigned long flags, rt, master_time_stamp;
193 #if DEBUG_TICK_SYNC
194 	struct {
195 		long rt;	/* roundtrip time */
196 		long master;	/* master's timestamp */
197 		long diff;	/* difference between midpoint and master's timestamp */
198 		long lat;	/* estimate of itc adjustment latency */
199 	} t[NUM_ROUNDS];
200 #endif
201 
202 	go[MASTER] = 1;
203 
204 	while (go[MASTER])
205 		rmb();
206 
207 	local_irq_save(flags);
208 	{
209 		for (i = 0; i < NUM_ROUNDS; i++) {
210 			delta = get_delta(&rt, &master_time_stamp);
211 			if (delta == 0)
212 				done = 1;	/* let's lock on to this... */
213 
214 			if (!done) {
215 				if (i > 0) {
216 					adjust_latency += -delta;
217 					adj = -delta + adjust_latency/4;
218 				} else
219 					adj = -delta;
220 
221 				tick_ops->add_tick(adj);
222 			}
223 #if DEBUG_TICK_SYNC
224 			t[i].rt = rt;
225 			t[i].master = master_time_stamp;
226 			t[i].diff = delta;
227 			t[i].lat = adjust_latency/4;
228 #endif
229 		}
230 	}
231 	local_irq_restore(flags);
232 
233 #if DEBUG_TICK_SYNC
234 	for (i = 0; i < NUM_ROUNDS; i++)
235 		printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
236 		       t[i].rt, t[i].master, t[i].diff, t[i].lat);
237 #endif
238 
239 	printk(KERN_INFO "CPU %d: synchronized TICK with master CPU "
240 	       "(last diff %ld cycles, maxerr %lu cycles)\n",
241 	       smp_processor_id(), delta, rt);
242 }
243 
244 static void smp_start_sync_tick_client(int cpu);
245 
246 static void smp_synchronize_one_tick(int cpu)
247 {
248 	unsigned long flags, i;
249 
250 	go[MASTER] = 0;
251 
252 	smp_start_sync_tick_client(cpu);
253 
254 	/* wait for client to be ready */
255 	while (!go[MASTER])
256 		rmb();
257 
258 	/* now let the client proceed into his loop */
259 	go[MASTER] = 0;
260 	membar_safe("#StoreLoad");
261 
262 	spin_lock_irqsave(&itc_sync_lock, flags);
263 	{
264 		for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
265 			while (!go[MASTER])
266 				rmb();
267 			go[MASTER] = 0;
268 			wmb();
269 			go[SLAVE] = tick_ops->get_tick();
270 			membar_safe("#StoreLoad");
271 		}
272 	}
273 	spin_unlock_irqrestore(&itc_sync_lock, flags);
274 }
275 
276 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
277 /* XXX Put this in some common place. XXX */
278 static unsigned long kimage_addr_to_ra(void *p)
279 {
280 	unsigned long val = (unsigned long) p;
281 
282 	return kern_base + (val - KERNBASE);
283 }
284 
285 static void __cpuinit ldom_startcpu_cpuid(unsigned int cpu, unsigned long thread_reg, void **descrp)
286 {
287 	extern unsigned long sparc64_ttable_tl0;
288 	extern unsigned long kern_locked_tte_data;
289 	struct hvtramp_descr *hdesc;
290 	unsigned long trampoline_ra;
291 	struct trap_per_cpu *tb;
292 	u64 tte_vaddr, tte_data;
293 	unsigned long hv_err;
294 	int i;
295 
296 	hdesc = kzalloc(sizeof(*hdesc) +
297 			(sizeof(struct hvtramp_mapping) *
298 			 num_kernel_image_mappings - 1),
299 			GFP_KERNEL);
300 	if (!hdesc) {
301 		printk(KERN_ERR "ldom_startcpu_cpuid: Cannot allocate "
302 		       "hvtramp_descr.\n");
303 		return;
304 	}
305 	*descrp = hdesc;
306 
307 	hdesc->cpu = cpu;
308 	hdesc->num_mappings = num_kernel_image_mappings;
309 
310 	tb = &trap_block[cpu];
311 
312 	hdesc->fault_info_va = (unsigned long) &tb->fault_info;
313 	hdesc->fault_info_pa = kimage_addr_to_ra(&tb->fault_info);
314 
315 	hdesc->thread_reg = thread_reg;
316 
317 	tte_vaddr = (unsigned long) KERNBASE;
318 	tte_data = kern_locked_tte_data;
319 
320 	for (i = 0; i < hdesc->num_mappings; i++) {
321 		hdesc->maps[i].vaddr = tte_vaddr;
322 		hdesc->maps[i].tte   = tte_data;
323 		tte_vaddr += 0x400000;
324 		tte_data  += 0x400000;
325 	}
326 
327 	trampoline_ra = kimage_addr_to_ra(hv_cpu_startup);
328 
329 	hv_err = sun4v_cpu_start(cpu, trampoline_ra,
330 				 kimage_addr_to_ra(&sparc64_ttable_tl0),
331 				 __pa(hdesc));
332 	if (hv_err)
333 		printk(KERN_ERR "ldom_startcpu_cpuid: sun4v_cpu_start() "
334 		       "gives error %lu\n", hv_err);
335 }
336 #endif
337 
338 extern unsigned long sparc64_cpu_startup;
339 
340 /* The OBP cpu startup callback truncates the 3rd arg cookie to
341  * 32-bits (I think) so to be safe we have it read the pointer
342  * contained here so we work on >4GB machines. -DaveM
343  */
344 static struct thread_info *cpu_new_thread = NULL;
345 
346 static int __cpuinit smp_boot_one_cpu(unsigned int cpu, struct task_struct *idle)
347 {
348 	unsigned long entry =
349 		(unsigned long)(&sparc64_cpu_startup);
350 	unsigned long cookie =
351 		(unsigned long)(&cpu_new_thread);
352 	void *descr = NULL;
353 	int timeout, ret;
354 
355 	callin_flag = 0;
356 	cpu_new_thread = task_thread_info(idle);
357 
358 	if (tlb_type == hypervisor) {
359 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
360 		if (ldom_domaining_enabled)
361 			ldom_startcpu_cpuid(cpu,
362 					    (unsigned long) cpu_new_thread,
363 					    &descr);
364 		else
365 #endif
366 			prom_startcpu_cpuid(cpu, entry, cookie);
367 	} else {
368 		struct device_node *dp = of_find_node_by_cpuid(cpu);
369 
370 		prom_startcpu(dp->phandle, entry, cookie);
371 	}
372 
373 	for (timeout = 0; timeout < 50000; timeout++) {
374 		if (callin_flag)
375 			break;
376 		udelay(100);
377 	}
378 
379 	if (callin_flag) {
380 		ret = 0;
381 	} else {
382 		printk("Processor %d is stuck.\n", cpu);
383 		ret = -ENODEV;
384 	}
385 	cpu_new_thread = NULL;
386 
387 	kfree(descr);
388 
389 	return ret;
390 }
391 
392 static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
393 {
394 	u64 result, target;
395 	int stuck, tmp;
396 
397 	if (this_is_starfire) {
398 		/* map to real upaid */
399 		cpu = (((cpu & 0x3c) << 1) |
400 			((cpu & 0x40) >> 4) |
401 			(cpu & 0x3));
402 	}
403 
404 	target = (cpu << 14) | 0x70;
405 again:
406 	/* Ok, this is the real Spitfire Errata #54.
407 	 * One must read back from a UDB internal register
408 	 * after writes to the UDB interrupt dispatch, but
409 	 * before the membar Sync for that write.
410 	 * So we use the high UDB control register (ASI 0x7f,
411 	 * ADDR 0x20) for the dummy read. -DaveM
412 	 */
413 	tmp = 0x40;
414 	__asm__ __volatile__(
415 	"wrpr	%1, %2, %%pstate\n\t"
416 	"stxa	%4, [%0] %3\n\t"
417 	"stxa	%5, [%0+%8] %3\n\t"
418 	"add	%0, %8, %0\n\t"
419 	"stxa	%6, [%0+%8] %3\n\t"
420 	"membar	#Sync\n\t"
421 	"stxa	%%g0, [%7] %3\n\t"
422 	"membar	#Sync\n\t"
423 	"mov	0x20, %%g1\n\t"
424 	"ldxa	[%%g1] 0x7f, %%g0\n\t"
425 	"membar	#Sync"
426 	: "=r" (tmp)
427 	: "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
428 	  "r" (data0), "r" (data1), "r" (data2), "r" (target),
429 	  "r" (0x10), "0" (tmp)
430         : "g1");
431 
432 	/* NOTE: PSTATE_IE is still clear. */
433 	stuck = 100000;
434 	do {
435 		__asm__ __volatile__("ldxa [%%g0] %1, %0"
436 			: "=r" (result)
437 			: "i" (ASI_INTR_DISPATCH_STAT));
438 		if (result == 0) {
439 			__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
440 					     : : "r" (pstate));
441 			return;
442 		}
443 		stuck -= 1;
444 		if (stuck == 0)
445 			break;
446 	} while (result & 0x1);
447 	__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
448 			     : : "r" (pstate));
449 	if (stuck == 0) {
450 		printk("CPU[%d]: mondo stuckage result[%016llx]\n",
451 		       smp_processor_id(), result);
452 	} else {
453 		udelay(2);
454 		goto again;
455 	}
456 }
457 
458 static void spitfire_xcall_deliver(struct trap_per_cpu *tb, int cnt)
459 {
460 	u64 *mondo, data0, data1, data2;
461 	u16 *cpu_list;
462 	u64 pstate;
463 	int i;
464 
465 	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
466 	cpu_list = __va(tb->cpu_list_pa);
467 	mondo = __va(tb->cpu_mondo_block_pa);
468 	data0 = mondo[0];
469 	data1 = mondo[1];
470 	data2 = mondo[2];
471 	for (i = 0; i < cnt; i++)
472 		spitfire_xcall_helper(data0, data1, data2, pstate, cpu_list[i]);
473 }
474 
475 /* Cheetah now allows to send the whole 64-bytes of data in the interrupt
476  * packet, but we have no use for that.  However we do take advantage of
477  * the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
478  */
479 static void cheetah_xcall_deliver(struct trap_per_cpu *tb, int cnt)
480 {
481 	int nack_busy_id, is_jbus, need_more;
482 	u64 *mondo, pstate, ver, busy_mask;
483 	u16 *cpu_list;
484 
485 	cpu_list = __va(tb->cpu_list_pa);
486 	mondo = __va(tb->cpu_mondo_block_pa);
487 
488 	/* Unfortunately, someone at Sun had the brilliant idea to make the
489 	 * busy/nack fields hard-coded by ITID number for this Ultra-III
490 	 * derivative processor.
491 	 */
492 	__asm__ ("rdpr %%ver, %0" : "=r" (ver));
493 	is_jbus = ((ver >> 32) == __JALAPENO_ID ||
494 		   (ver >> 32) == __SERRANO_ID);
495 
496 	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
497 
498 retry:
499 	need_more = 0;
500 	__asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
501 			     : : "r" (pstate), "i" (PSTATE_IE));
502 
503 	/* Setup the dispatch data registers. */
504 	__asm__ __volatile__("stxa	%0, [%3] %6\n\t"
505 			     "stxa	%1, [%4] %6\n\t"
506 			     "stxa	%2, [%5] %6\n\t"
507 			     "membar	#Sync\n\t"
508 			     : /* no outputs */
509 			     : "r" (mondo[0]), "r" (mondo[1]), "r" (mondo[2]),
510 			       "r" (0x40), "r" (0x50), "r" (0x60),
511 			       "i" (ASI_INTR_W));
512 
513 	nack_busy_id = 0;
514 	busy_mask = 0;
515 	{
516 		int i;
517 
518 		for (i = 0; i < cnt; i++) {
519 			u64 target, nr;
520 
521 			nr = cpu_list[i];
522 			if (nr == 0xffff)
523 				continue;
524 
525 			target = (nr << 14) | 0x70;
526 			if (is_jbus) {
527 				busy_mask |= (0x1UL << (nr * 2));
528 			} else {
529 				target |= (nack_busy_id << 24);
530 				busy_mask |= (0x1UL <<
531 					      (nack_busy_id * 2));
532 			}
533 			__asm__ __volatile__(
534 				"stxa	%%g0, [%0] %1\n\t"
535 				"membar	#Sync\n\t"
536 				: /* no outputs */
537 				: "r" (target), "i" (ASI_INTR_W));
538 			nack_busy_id++;
539 			if (nack_busy_id == 32) {
540 				need_more = 1;
541 				break;
542 			}
543 		}
544 	}
545 
546 	/* Now, poll for completion. */
547 	{
548 		u64 dispatch_stat, nack_mask;
549 		long stuck;
550 
551 		stuck = 100000 * nack_busy_id;
552 		nack_mask = busy_mask << 1;
553 		do {
554 			__asm__ __volatile__("ldxa	[%%g0] %1, %0"
555 					     : "=r" (dispatch_stat)
556 					     : "i" (ASI_INTR_DISPATCH_STAT));
557 			if (!(dispatch_stat & (busy_mask | nack_mask))) {
558 				__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
559 						     : : "r" (pstate));
560 				if (unlikely(need_more)) {
561 					int i, this_cnt = 0;
562 					for (i = 0; i < cnt; i++) {
563 						if (cpu_list[i] == 0xffff)
564 							continue;
565 						cpu_list[i] = 0xffff;
566 						this_cnt++;
567 						if (this_cnt == 32)
568 							break;
569 					}
570 					goto retry;
571 				}
572 				return;
573 			}
574 			if (!--stuck)
575 				break;
576 		} while (dispatch_stat & busy_mask);
577 
578 		__asm__ __volatile__("wrpr %0, 0x0, %%pstate"
579 				     : : "r" (pstate));
580 
581 		if (dispatch_stat & busy_mask) {
582 			/* Busy bits will not clear, continue instead
583 			 * of freezing up on this cpu.
584 			 */
585 			printk("CPU[%d]: mondo stuckage result[%016llx]\n",
586 			       smp_processor_id(), dispatch_stat);
587 		} else {
588 			int i, this_busy_nack = 0;
589 
590 			/* Delay some random time with interrupts enabled
591 			 * to prevent deadlock.
592 			 */
593 			udelay(2 * nack_busy_id);
594 
595 			/* Clear out the mask bits for cpus which did not
596 			 * NACK us.
597 			 */
598 			for (i = 0; i < cnt; i++) {
599 				u64 check_mask, nr;
600 
601 				nr = cpu_list[i];
602 				if (nr == 0xffff)
603 					continue;
604 
605 				if (is_jbus)
606 					check_mask = (0x2UL << (2*nr));
607 				else
608 					check_mask = (0x2UL <<
609 						      this_busy_nack);
610 				if ((dispatch_stat & check_mask) == 0)
611 					cpu_list[i] = 0xffff;
612 				this_busy_nack += 2;
613 				if (this_busy_nack == 64)
614 					break;
615 			}
616 
617 			goto retry;
618 		}
619 	}
620 }
621 
622 /* Multi-cpu list version.  */
623 static void hypervisor_xcall_deliver(struct trap_per_cpu *tb, int cnt)
624 {
625 	int retries, this_cpu, prev_sent, i, saw_cpu_error;
626 	unsigned long status;
627 	u16 *cpu_list;
628 
629 	this_cpu = smp_processor_id();
630 
631 	cpu_list = __va(tb->cpu_list_pa);
632 
633 	saw_cpu_error = 0;
634 	retries = 0;
635 	prev_sent = 0;
636 	do {
637 		int forward_progress, n_sent;
638 
639 		status = sun4v_cpu_mondo_send(cnt,
640 					      tb->cpu_list_pa,
641 					      tb->cpu_mondo_block_pa);
642 
643 		/* HV_EOK means all cpus received the xcall, we're done.  */
644 		if (likely(status == HV_EOK))
645 			break;
646 
647 		/* First, see if we made any forward progress.
648 		 *
649 		 * The hypervisor indicates successful sends by setting
650 		 * cpu list entries to the value 0xffff.
651 		 */
652 		n_sent = 0;
653 		for (i = 0; i < cnt; i++) {
654 			if (likely(cpu_list[i] == 0xffff))
655 				n_sent++;
656 		}
657 
658 		forward_progress = 0;
659 		if (n_sent > prev_sent)
660 			forward_progress = 1;
661 
662 		prev_sent = n_sent;
663 
664 		/* If we get a HV_ECPUERROR, then one or more of the cpus
665 		 * in the list are in error state.  Use the cpu_state()
666 		 * hypervisor call to find out which cpus are in error state.
667 		 */
668 		if (unlikely(status == HV_ECPUERROR)) {
669 			for (i = 0; i < cnt; i++) {
670 				long err;
671 				u16 cpu;
672 
673 				cpu = cpu_list[i];
674 				if (cpu == 0xffff)
675 					continue;
676 
677 				err = sun4v_cpu_state(cpu);
678 				if (err == HV_CPU_STATE_ERROR) {
679 					saw_cpu_error = (cpu + 1);
680 					cpu_list[i] = 0xffff;
681 				}
682 			}
683 		} else if (unlikely(status != HV_EWOULDBLOCK))
684 			goto fatal_mondo_error;
685 
686 		/* Don't bother rewriting the CPU list, just leave the
687 		 * 0xffff and non-0xffff entries in there and the
688 		 * hypervisor will do the right thing.
689 		 *
690 		 * Only advance timeout state if we didn't make any
691 		 * forward progress.
692 		 */
693 		if (unlikely(!forward_progress)) {
694 			if (unlikely(++retries > 10000))
695 				goto fatal_mondo_timeout;
696 
697 			/* Delay a little bit to let other cpus catch up
698 			 * on their cpu mondo queue work.
699 			 */
700 			udelay(2 * cnt);
701 		}
702 	} while (1);
703 
704 	if (unlikely(saw_cpu_error))
705 		goto fatal_mondo_cpu_error;
706 
707 	return;
708 
709 fatal_mondo_cpu_error:
710 	printk(KERN_CRIT "CPU[%d]: SUN4V mondo cpu error, some target cpus "
711 	       "(including %d) were in error state\n",
712 	       this_cpu, saw_cpu_error - 1);
713 	return;
714 
715 fatal_mondo_timeout:
716 	printk(KERN_CRIT "CPU[%d]: SUN4V mondo timeout, no forward "
717 	       " progress after %d retries.\n",
718 	       this_cpu, retries);
719 	goto dump_cpu_list_and_out;
720 
721 fatal_mondo_error:
722 	printk(KERN_CRIT "CPU[%d]: Unexpected SUN4V mondo error %lu\n",
723 	       this_cpu, status);
724 	printk(KERN_CRIT "CPU[%d]: Args were cnt(%d) cpulist_pa(%lx) "
725 	       "mondo_block_pa(%lx)\n",
726 	       this_cpu, cnt, tb->cpu_list_pa, tb->cpu_mondo_block_pa);
727 
728 dump_cpu_list_and_out:
729 	printk(KERN_CRIT "CPU[%d]: CPU list [ ", this_cpu);
730 	for (i = 0; i < cnt; i++)
731 		printk("%u ", cpu_list[i]);
732 	printk("]\n");
733 }
734 
735 static void (*xcall_deliver_impl)(struct trap_per_cpu *, int);
736 
737 static void xcall_deliver(u64 data0, u64 data1, u64 data2, const cpumask_t *mask)
738 {
739 	struct trap_per_cpu *tb;
740 	int this_cpu, i, cnt;
741 	unsigned long flags;
742 	u16 *cpu_list;
743 	u64 *mondo;
744 
745 	/* We have to do this whole thing with interrupts fully disabled.
746 	 * Otherwise if we send an xcall from interrupt context it will
747 	 * corrupt both our mondo block and cpu list state.
748 	 *
749 	 * One consequence of this is that we cannot use timeout mechanisms
750 	 * that depend upon interrupts being delivered locally.  So, for
751 	 * example, we cannot sample jiffies and expect it to advance.
752 	 *
753 	 * Fortunately, udelay() uses %stick/%tick so we can use that.
754 	 */
755 	local_irq_save(flags);
756 
757 	this_cpu = smp_processor_id();
758 	tb = &trap_block[this_cpu];
759 
760 	mondo = __va(tb->cpu_mondo_block_pa);
761 	mondo[0] = data0;
762 	mondo[1] = data1;
763 	mondo[2] = data2;
764 	wmb();
765 
766 	cpu_list = __va(tb->cpu_list_pa);
767 
768 	/* Setup the initial cpu list.  */
769 	cnt = 0;
770 	for_each_cpu(i, mask) {
771 		if (i == this_cpu || !cpu_online(i))
772 			continue;
773 		cpu_list[cnt++] = i;
774 	}
775 
776 	if (cnt)
777 		xcall_deliver_impl(tb, cnt);
778 
779 	local_irq_restore(flags);
780 }
781 
782 /* Send cross call to all processors mentioned in MASK_P
783  * except self.  Really, there are only two cases currently,
784  * "cpu_online_mask" and "mm_cpumask(mm)".
785  */
786 static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, const cpumask_t *mask)
787 {
788 	u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
789 
790 	xcall_deliver(data0, data1, data2, mask);
791 }
792 
793 /* Send cross call to all processors except self. */
794 static void smp_cross_call(unsigned long *func, u32 ctx, u64 data1, u64 data2)
795 {
796 	smp_cross_call_masked(func, ctx, data1, data2, cpu_online_mask);
797 }
798 
799 extern unsigned long xcall_sync_tick;
800 
801 static void smp_start_sync_tick_client(int cpu)
802 {
803 	xcall_deliver((u64) &xcall_sync_tick, 0, 0,
804 		      cpumask_of(cpu));
805 }
806 
807 extern unsigned long xcall_call_function;
808 
809 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
810 {
811 	xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
812 }
813 
814 extern unsigned long xcall_call_function_single;
815 
816 void arch_send_call_function_single_ipi(int cpu)
817 {
818 	xcall_deliver((u64) &xcall_call_function_single, 0, 0,
819 		      cpumask_of(cpu));
820 }
821 
822 void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs)
823 {
824 	clear_softint(1 << irq);
825 	generic_smp_call_function_interrupt();
826 }
827 
828 void __irq_entry smp_call_function_single_client(int irq, struct pt_regs *regs)
829 {
830 	clear_softint(1 << irq);
831 	generic_smp_call_function_single_interrupt();
832 }
833 
834 static void tsb_sync(void *info)
835 {
836 	struct trap_per_cpu *tp = &trap_block[raw_smp_processor_id()];
837 	struct mm_struct *mm = info;
838 
839 	/* It is not valid to test "current->active_mm == mm" here.
840 	 *
841 	 * The value of "current" is not changed atomically with
842 	 * switch_mm().  But that's OK, we just need to check the
843 	 * current cpu's trap block PGD physical address.
844 	 */
845 	if (tp->pgd_paddr == __pa(mm->pgd))
846 		tsb_context_switch(mm);
847 }
848 
849 void smp_tsb_sync(struct mm_struct *mm)
850 {
851 	smp_call_function_many(mm_cpumask(mm), tsb_sync, mm, 1);
852 }
853 
854 extern unsigned long xcall_flush_tlb_mm;
855 extern unsigned long xcall_flush_tlb_pending;
856 extern unsigned long xcall_flush_tlb_kernel_range;
857 extern unsigned long xcall_fetch_glob_regs;
858 extern unsigned long xcall_receive_signal;
859 extern unsigned long xcall_new_mmu_context_version;
860 #ifdef CONFIG_KGDB
861 extern unsigned long xcall_kgdb_capture;
862 #endif
863 
864 #ifdef DCACHE_ALIASING_POSSIBLE
865 extern unsigned long xcall_flush_dcache_page_cheetah;
866 #endif
867 extern unsigned long xcall_flush_dcache_page_spitfire;
868 
869 #ifdef CONFIG_DEBUG_DCFLUSH
870 extern atomic_t dcpage_flushes;
871 extern atomic_t dcpage_flushes_xcall;
872 #endif
873 
874 static inline void __local_flush_dcache_page(struct page *page)
875 {
876 #ifdef DCACHE_ALIASING_POSSIBLE
877 	__flush_dcache_page(page_address(page),
878 			    ((tlb_type == spitfire) &&
879 			     page_mapping(page) != NULL));
880 #else
881 	if (page_mapping(page) != NULL &&
882 	    tlb_type == spitfire)
883 		__flush_icache_page(__pa(page_address(page)));
884 #endif
885 }
886 
887 void smp_flush_dcache_page_impl(struct page *page, int cpu)
888 {
889 	int this_cpu;
890 
891 	if (tlb_type == hypervisor)
892 		return;
893 
894 #ifdef CONFIG_DEBUG_DCFLUSH
895 	atomic_inc(&dcpage_flushes);
896 #endif
897 
898 	this_cpu = get_cpu();
899 
900 	if (cpu == this_cpu) {
901 		__local_flush_dcache_page(page);
902 	} else if (cpu_online(cpu)) {
903 		void *pg_addr = page_address(page);
904 		u64 data0 = 0;
905 
906 		if (tlb_type == spitfire) {
907 			data0 = ((u64)&xcall_flush_dcache_page_spitfire);
908 			if (page_mapping(page) != NULL)
909 				data0 |= ((u64)1 << 32);
910 		} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
911 #ifdef DCACHE_ALIASING_POSSIBLE
912 			data0 =	((u64)&xcall_flush_dcache_page_cheetah);
913 #endif
914 		}
915 		if (data0) {
916 			xcall_deliver(data0, __pa(pg_addr),
917 				      (u64) pg_addr, cpumask_of(cpu));
918 #ifdef CONFIG_DEBUG_DCFLUSH
919 			atomic_inc(&dcpage_flushes_xcall);
920 #endif
921 		}
922 	}
923 
924 	put_cpu();
925 }
926 
927 void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
928 {
929 	void *pg_addr;
930 	u64 data0;
931 
932 	if (tlb_type == hypervisor)
933 		return;
934 
935 	preempt_disable();
936 
937 #ifdef CONFIG_DEBUG_DCFLUSH
938 	atomic_inc(&dcpage_flushes);
939 #endif
940 	data0 = 0;
941 	pg_addr = page_address(page);
942 	if (tlb_type == spitfire) {
943 		data0 = ((u64)&xcall_flush_dcache_page_spitfire);
944 		if (page_mapping(page) != NULL)
945 			data0 |= ((u64)1 << 32);
946 	} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
947 #ifdef DCACHE_ALIASING_POSSIBLE
948 		data0 = ((u64)&xcall_flush_dcache_page_cheetah);
949 #endif
950 	}
951 	if (data0) {
952 		xcall_deliver(data0, __pa(pg_addr),
953 			      (u64) pg_addr, cpu_online_mask);
954 #ifdef CONFIG_DEBUG_DCFLUSH
955 		atomic_inc(&dcpage_flushes_xcall);
956 #endif
957 	}
958 	__local_flush_dcache_page(page);
959 
960 	preempt_enable();
961 }
962 
963 void __irq_entry smp_new_mmu_context_version_client(int irq, struct pt_regs *regs)
964 {
965 	struct mm_struct *mm;
966 	unsigned long flags;
967 
968 	clear_softint(1 << irq);
969 
970 	/* See if we need to allocate a new TLB context because
971 	 * the version of the one we are using is now out of date.
972 	 */
973 	mm = current->active_mm;
974 	if (unlikely(!mm || (mm == &init_mm)))
975 		return;
976 
977 	spin_lock_irqsave(&mm->context.lock, flags);
978 
979 	if (unlikely(!CTX_VALID(mm->context)))
980 		get_new_mmu_context(mm);
981 
982 	spin_unlock_irqrestore(&mm->context.lock, flags);
983 
984 	load_secondary_context(mm);
985 	__flush_tlb_mm(CTX_HWBITS(mm->context),
986 		       SECONDARY_CONTEXT);
987 }
988 
989 void smp_new_mmu_context_version(void)
990 {
991 	smp_cross_call(&xcall_new_mmu_context_version, 0, 0, 0);
992 }
993 
994 #ifdef CONFIG_KGDB
995 void kgdb_roundup_cpus(unsigned long flags)
996 {
997 	smp_cross_call(&xcall_kgdb_capture, 0, 0, 0);
998 }
999 #endif
1000 
1001 void smp_fetch_global_regs(void)
1002 {
1003 	smp_cross_call(&xcall_fetch_glob_regs, 0, 0, 0);
1004 }
1005 
1006 /* We know that the window frames of the user have been flushed
1007  * to the stack before we get here because all callers of us
1008  * are flush_tlb_*() routines, and these run after flush_cache_*()
1009  * which performs the flushw.
1010  *
1011  * The SMP TLB coherency scheme we use works as follows:
1012  *
1013  * 1) mm->cpu_vm_mask is a bit mask of which cpus an address
1014  *    space has (potentially) executed on, this is the heuristic
1015  *    we use to avoid doing cross calls.
1016  *
1017  *    Also, for flushing from kswapd and also for clones, we
1018  *    use cpu_vm_mask as the list of cpus to make run the TLB.
1019  *
1020  * 2) TLB context numbers are shared globally across all processors
1021  *    in the system, this allows us to play several games to avoid
1022  *    cross calls.
1023  *
1024  *    One invariant is that when a cpu switches to a process, and
1025  *    that processes tsk->active_mm->cpu_vm_mask does not have the
1026  *    current cpu's bit set, that tlb context is flushed locally.
1027  *
1028  *    If the address space is non-shared (ie. mm->count == 1) we avoid
1029  *    cross calls when we want to flush the currently running process's
1030  *    tlb state.  This is done by clearing all cpu bits except the current
1031  *    processor's in current->mm->cpu_vm_mask and performing the
1032  *    flush locally only.  This will force any subsequent cpus which run
1033  *    this task to flush the context from the local tlb if the process
1034  *    migrates to another cpu (again).
1035  *
1036  * 3) For shared address spaces (threads) and swapping we bite the
1037  *    bullet for most cases and perform the cross call (but only to
1038  *    the cpus listed in cpu_vm_mask).
1039  *
1040  *    The performance gain from "optimizing" away the cross call for threads is
1041  *    questionable (in theory the big win for threads is the massive sharing of
1042  *    address space state across processors).
1043  */
1044 
1045 /* This currently is only used by the hugetlb arch pre-fault
1046  * hook on UltraSPARC-III+ and later when changing the pagesize
1047  * bits of the context register for an address space.
1048  */
1049 void smp_flush_tlb_mm(struct mm_struct *mm)
1050 {
1051 	u32 ctx = CTX_HWBITS(mm->context);
1052 	int cpu = get_cpu();
1053 
1054 	if (atomic_read(&mm->mm_users) == 1) {
1055 		cpumask_copy(mm_cpumask(mm), cpumask_of(cpu));
1056 		goto local_flush_and_out;
1057 	}
1058 
1059 	smp_cross_call_masked(&xcall_flush_tlb_mm,
1060 			      ctx, 0, 0,
1061 			      mm_cpumask(mm));
1062 
1063 local_flush_and_out:
1064 	__flush_tlb_mm(ctx, SECONDARY_CONTEXT);
1065 
1066 	put_cpu();
1067 }
1068 
1069 void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
1070 {
1071 	u32 ctx = CTX_HWBITS(mm->context);
1072 	int cpu = get_cpu();
1073 
1074 	if (mm == current->mm && atomic_read(&mm->mm_users) == 1)
1075 		cpumask_copy(mm_cpumask(mm), cpumask_of(cpu));
1076 	else
1077 		smp_cross_call_masked(&xcall_flush_tlb_pending,
1078 				      ctx, nr, (unsigned long) vaddrs,
1079 				      mm_cpumask(mm));
1080 
1081 	__flush_tlb_pending(ctx, nr, vaddrs);
1082 
1083 	put_cpu();
1084 }
1085 
1086 void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
1087 {
1088 	start &= PAGE_MASK;
1089 	end    = PAGE_ALIGN(end);
1090 	if (start != end) {
1091 		smp_cross_call(&xcall_flush_tlb_kernel_range,
1092 			       0, start, end);
1093 
1094 		__flush_tlb_kernel_range(start, end);
1095 	}
1096 }
1097 
1098 /* CPU capture. */
1099 /* #define CAPTURE_DEBUG */
1100 extern unsigned long xcall_capture;
1101 
1102 static atomic_t smp_capture_depth = ATOMIC_INIT(0);
1103 static atomic_t smp_capture_registry = ATOMIC_INIT(0);
1104 static unsigned long penguins_are_doing_time;
1105 
1106 void smp_capture(void)
1107 {
1108 	int result = atomic_add_ret(1, &smp_capture_depth);
1109 
1110 	if (result == 1) {
1111 		int ncpus = num_online_cpus();
1112 
1113 #ifdef CAPTURE_DEBUG
1114 		printk("CPU[%d]: Sending penguins to jail...",
1115 		       smp_processor_id());
1116 #endif
1117 		penguins_are_doing_time = 1;
1118 		atomic_inc(&smp_capture_registry);
1119 		smp_cross_call(&xcall_capture, 0, 0, 0);
1120 		while (atomic_read(&smp_capture_registry) != ncpus)
1121 			rmb();
1122 #ifdef CAPTURE_DEBUG
1123 		printk("done\n");
1124 #endif
1125 	}
1126 }
1127 
1128 void smp_release(void)
1129 {
1130 	if (atomic_dec_and_test(&smp_capture_depth)) {
1131 #ifdef CAPTURE_DEBUG
1132 		printk("CPU[%d]: Giving pardon to "
1133 		       "imprisoned penguins\n",
1134 		       smp_processor_id());
1135 #endif
1136 		penguins_are_doing_time = 0;
1137 		membar_safe("#StoreLoad");
1138 		atomic_dec(&smp_capture_registry);
1139 	}
1140 }
1141 
1142 /* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE
1143  * set, so they can service tlb flush xcalls...
1144  */
1145 extern void prom_world(int);
1146 
1147 void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs)
1148 {
1149 	clear_softint(1 << irq);
1150 
1151 	preempt_disable();
1152 
1153 	__asm__ __volatile__("flushw");
1154 	prom_world(1);
1155 	atomic_inc(&smp_capture_registry);
1156 	membar_safe("#StoreLoad");
1157 	while (penguins_are_doing_time)
1158 		rmb();
1159 	atomic_dec(&smp_capture_registry);
1160 	prom_world(0);
1161 
1162 	preempt_enable();
1163 }
1164 
1165 /* /proc/profile writes can call this, don't __init it please. */
1166 int setup_profiling_timer(unsigned int multiplier)
1167 {
1168 	return -EINVAL;
1169 }
1170 
1171 void __init smp_prepare_cpus(unsigned int max_cpus)
1172 {
1173 }
1174 
1175 void __devinit smp_prepare_boot_cpu(void)
1176 {
1177 }
1178 
1179 void __init smp_setup_processor_id(void)
1180 {
1181 	if (tlb_type == spitfire)
1182 		xcall_deliver_impl = spitfire_xcall_deliver;
1183 	else if (tlb_type == cheetah || tlb_type == cheetah_plus)
1184 		xcall_deliver_impl = cheetah_xcall_deliver;
1185 	else
1186 		xcall_deliver_impl = hypervisor_xcall_deliver;
1187 }
1188 
1189 void __devinit smp_fill_in_sib_core_maps(void)
1190 {
1191 	unsigned int i;
1192 
1193 	for_each_present_cpu(i) {
1194 		unsigned int j;
1195 
1196 		cpumask_clear(&cpu_core_map[i]);
1197 		if (cpu_data(i).core_id == 0) {
1198 			cpumask_set_cpu(i, &cpu_core_map[i]);
1199 			continue;
1200 		}
1201 
1202 		for_each_present_cpu(j) {
1203 			if (cpu_data(i).core_id ==
1204 			    cpu_data(j).core_id)
1205 				cpumask_set_cpu(j, &cpu_core_map[i]);
1206 		}
1207 	}
1208 
1209 	for_each_present_cpu(i) {
1210 		unsigned int j;
1211 
1212 		cpumask_clear(&per_cpu(cpu_sibling_map, i));
1213 		if (cpu_data(i).proc_id == -1) {
1214 			cpumask_set_cpu(i, &per_cpu(cpu_sibling_map, i));
1215 			continue;
1216 		}
1217 
1218 		for_each_present_cpu(j) {
1219 			if (cpu_data(i).proc_id ==
1220 			    cpu_data(j).proc_id)
1221 				cpumask_set_cpu(j, &per_cpu(cpu_sibling_map, i));
1222 		}
1223 	}
1224 }
1225 
1226 int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *tidle)
1227 {
1228 	int ret = smp_boot_one_cpu(cpu, tidle);
1229 
1230 	if (!ret) {
1231 		cpumask_set_cpu(cpu, &smp_commenced_mask);
1232 		while (!cpu_online(cpu))
1233 			mb();
1234 		if (!cpu_online(cpu)) {
1235 			ret = -ENODEV;
1236 		} else {
1237 			/* On SUN4V, writes to %tick and %stick are
1238 			 * not allowed.
1239 			 */
1240 			if (tlb_type != hypervisor)
1241 				smp_synchronize_one_tick(cpu);
1242 		}
1243 	}
1244 	return ret;
1245 }
1246 
1247 #ifdef CONFIG_HOTPLUG_CPU
1248 void cpu_play_dead(void)
1249 {
1250 	int cpu = smp_processor_id();
1251 	unsigned long pstate;
1252 
1253 	idle_task_exit();
1254 
1255 	if (tlb_type == hypervisor) {
1256 		struct trap_per_cpu *tb = &trap_block[cpu];
1257 
1258 		sun4v_cpu_qconf(HV_CPU_QUEUE_CPU_MONDO,
1259 				tb->cpu_mondo_pa, 0);
1260 		sun4v_cpu_qconf(HV_CPU_QUEUE_DEVICE_MONDO,
1261 				tb->dev_mondo_pa, 0);
1262 		sun4v_cpu_qconf(HV_CPU_QUEUE_RES_ERROR,
1263 				tb->resum_mondo_pa, 0);
1264 		sun4v_cpu_qconf(HV_CPU_QUEUE_NONRES_ERROR,
1265 				tb->nonresum_mondo_pa, 0);
1266 	}
1267 
1268 	cpumask_clear_cpu(cpu, &smp_commenced_mask);
1269 	membar_safe("#Sync");
1270 
1271 	local_irq_disable();
1272 
1273 	__asm__ __volatile__(
1274 		"rdpr	%%pstate, %0\n\t"
1275 		"wrpr	%0, %1, %%pstate"
1276 		: "=r" (pstate)
1277 		: "i" (PSTATE_IE));
1278 
1279 	while (1)
1280 		barrier();
1281 }
1282 
1283 int __cpu_disable(void)
1284 {
1285 	int cpu = smp_processor_id();
1286 	cpuinfo_sparc *c;
1287 	int i;
1288 
1289 	for_each_cpu(i, &cpu_core_map[cpu])
1290 		cpumask_clear_cpu(cpu, &cpu_core_map[i]);
1291 	cpumask_clear(&cpu_core_map[cpu]);
1292 
1293 	for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu))
1294 		cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i));
1295 	cpumask_clear(&per_cpu(cpu_sibling_map, cpu));
1296 
1297 	c = &cpu_data(cpu);
1298 
1299 	c->core_id = 0;
1300 	c->proc_id = -1;
1301 
1302 	smp_wmb();
1303 
1304 	/* Make sure no interrupts point to this cpu.  */
1305 	fixup_irqs();
1306 
1307 	local_irq_enable();
1308 	mdelay(1);
1309 	local_irq_disable();
1310 
1311 	ipi_call_lock();
1312 	set_cpu_online(cpu, false);
1313 	ipi_call_unlock();
1314 
1315 	cpu_map_rebuild();
1316 
1317 	return 0;
1318 }
1319 
1320 void __cpu_die(unsigned int cpu)
1321 {
1322 	int i;
1323 
1324 	for (i = 0; i < 100; i++) {
1325 		smp_rmb();
1326 		if (!cpumask_test_cpu(cpu, &smp_commenced_mask))
1327 			break;
1328 		msleep(100);
1329 	}
1330 	if (cpumask_test_cpu(cpu, &smp_commenced_mask)) {
1331 		printk(KERN_ERR "CPU %u didn't die...\n", cpu);
1332 	} else {
1333 #if defined(CONFIG_SUN_LDOMS)
1334 		unsigned long hv_err;
1335 		int limit = 100;
1336 
1337 		do {
1338 			hv_err = sun4v_cpu_stop(cpu);
1339 			if (hv_err == HV_EOK) {
1340 				set_cpu_present(cpu, false);
1341 				break;
1342 			}
1343 		} while (--limit > 0);
1344 		if (limit <= 0) {
1345 			printk(KERN_ERR "sun4v_cpu_stop() fails err=%lu\n",
1346 			       hv_err);
1347 		}
1348 #endif
1349 	}
1350 }
1351 #endif
1352 
1353 void __init smp_cpus_done(unsigned int max_cpus)
1354 {
1355 	pcr_arch_init();
1356 }
1357 
1358 void smp_send_reschedule(int cpu)
1359 {
1360 	xcall_deliver((u64) &xcall_receive_signal, 0, 0,
1361 		      cpumask_of(cpu));
1362 }
1363 
1364 void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs)
1365 {
1366 	clear_softint(1 << irq);
1367 	scheduler_ipi();
1368 }
1369 
1370 /* This is a nop because we capture all other cpus
1371  * anyways when making the PROM active.
1372  */
1373 void smp_send_stop(void)
1374 {
1375 }
1376 
1377 /**
1378  * pcpu_alloc_bootmem - NUMA friendly alloc_bootmem wrapper for percpu
1379  * @cpu: cpu to allocate for
1380  * @size: size allocation in bytes
1381  * @align: alignment
1382  *
1383  * Allocate @size bytes aligned at @align for cpu @cpu.  This wrapper
1384  * does the right thing for NUMA regardless of the current
1385  * configuration.
1386  *
1387  * RETURNS:
1388  * Pointer to the allocated area on success, NULL on failure.
1389  */
1390 static void * __init pcpu_alloc_bootmem(unsigned int cpu, size_t size,
1391 					size_t align)
1392 {
1393 	const unsigned long goal = __pa(MAX_DMA_ADDRESS);
1394 #ifdef CONFIG_NEED_MULTIPLE_NODES
1395 	int node = cpu_to_node(cpu);
1396 	void *ptr;
1397 
1398 	if (!node_online(node) || !NODE_DATA(node)) {
1399 		ptr = __alloc_bootmem(size, align, goal);
1400 		pr_info("cpu %d has no node %d or node-local memory\n",
1401 			cpu, node);
1402 		pr_debug("per cpu data for cpu%d %lu bytes at %016lx\n",
1403 			 cpu, size, __pa(ptr));
1404 	} else {
1405 		ptr = __alloc_bootmem_node(NODE_DATA(node),
1406 					   size, align, goal);
1407 		pr_debug("per cpu data for cpu%d %lu bytes on node%d at "
1408 			 "%016lx\n", cpu, size, node, __pa(ptr));
1409 	}
1410 	return ptr;
1411 #else
1412 	return __alloc_bootmem(size, align, goal);
1413 #endif
1414 }
1415 
1416 static void __init pcpu_free_bootmem(void *ptr, size_t size)
1417 {
1418 	free_bootmem(__pa(ptr), size);
1419 }
1420 
1421 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
1422 {
1423 	if (cpu_to_node(from) == cpu_to_node(to))
1424 		return LOCAL_DISTANCE;
1425 	else
1426 		return REMOTE_DISTANCE;
1427 }
1428 
1429 static void __init pcpu_populate_pte(unsigned long addr)
1430 {
1431 	pgd_t *pgd = pgd_offset_k(addr);
1432 	pud_t *pud;
1433 	pmd_t *pmd;
1434 
1435 	pud = pud_offset(pgd, addr);
1436 	if (pud_none(*pud)) {
1437 		pmd_t *new;
1438 
1439 		new = __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1440 		pud_populate(&init_mm, pud, new);
1441 	}
1442 
1443 	pmd = pmd_offset(pud, addr);
1444 	if (!pmd_present(*pmd)) {
1445 		pte_t *new;
1446 
1447 		new = __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1448 		pmd_populate_kernel(&init_mm, pmd, new);
1449 	}
1450 }
1451 
1452 void __init setup_per_cpu_areas(void)
1453 {
1454 	unsigned long delta;
1455 	unsigned int cpu;
1456 	int rc = -EINVAL;
1457 
1458 	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
1459 		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
1460 					    PERCPU_DYNAMIC_RESERVE, 4 << 20,
1461 					    pcpu_cpu_distance,
1462 					    pcpu_alloc_bootmem,
1463 					    pcpu_free_bootmem);
1464 		if (rc)
1465 			pr_warning("PERCPU: %s allocator failed (%d), "
1466 				   "falling back to page size\n",
1467 				   pcpu_fc_names[pcpu_chosen_fc], rc);
1468 	}
1469 	if (rc < 0)
1470 		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
1471 					   pcpu_alloc_bootmem,
1472 					   pcpu_free_bootmem,
1473 					   pcpu_populate_pte);
1474 	if (rc < 0)
1475 		panic("cannot initialize percpu area (err=%d)", rc);
1476 
1477 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
1478 	for_each_possible_cpu(cpu)
1479 		__per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];
1480 
1481 	/* Setup %g5 for the boot cpu.  */
1482 	__local_per_cpu_offset = __per_cpu_offset(smp_processor_id());
1483 
1484 	of_fill_in_cpu_data();
1485 	if (tlb_type == hypervisor)
1486 		mdesc_fill_in_cpu_data(cpu_all_mask);
1487 }
1488