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
61DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
62cpumask_t cpu_core_map[NR_CPUS] __read_mostly =
63	{ [0 ... NR_CPUS-1] = CPU_MASK_NONE };
64
65cpumask_t cpu_core_sib_map[NR_CPUS] __read_mostly = {
66	[0 ... NR_CPUS-1] = CPU_MASK_NONE };
67
68cpumask_t cpu_core_sib_cache_map[NR_CPUS] __read_mostly = {
69	[0 ... NR_CPUS - 1] = CPU_MASK_NONE };
70
71EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
72EXPORT_SYMBOL(cpu_core_map);
73EXPORT_SYMBOL(cpu_core_sib_map);
74EXPORT_SYMBOL(cpu_core_sib_cache_map);
75
76static cpumask_t smp_commenced_mask;
77
78static DEFINE_PER_CPU(bool, poke);
79static bool cpu_poke;
80
81void 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
90void 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
100extern void setup_sparc64_timer(void);
101
102static volatile unsigned long callin_flag = 0;
103
104void 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
146void 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
165static DEFINE_RAW_SPINLOCK(itc_sync_lock);
166static unsigned long go[SLAVE + 1];
167
168#define DEBUG_TICK_SYNC	0
169
170static 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
200void 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
255static void smp_start_sync_tick_client(int cpu);
256
257static 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)
288static 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
342extern 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 */
348static struct thread_info *cpu_new_thread = NULL;
349
350static 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
396static 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;
409again:
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
462static 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 */
483static 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
502retry:
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 */
645static 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
761xcall_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
771fatal_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
777fatal_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
784static void (*xcall_deliver_impl)(struct trap_per_cpu *, int);
785
786static 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 */
835static 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. */
843static 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
848extern unsigned long xcall_sync_tick;
849
850static void smp_start_sync_tick_client(int cpu)
851{
852	xcall_deliver((u64) &xcall_sync_tick, 0, 0,
853		      cpumask_of(cpu));
854}
855
856extern unsigned long xcall_call_function;
857
858void arch_send_call_function_ipi_mask(const struct cpumask *mask)
859{
860	xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
861}
862
863extern unsigned long xcall_call_function_single;
864
865void 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
871void __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
879void __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
887static 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
902void smp_tsb_sync(struct mm_struct *mm)
903{
904	smp_call_function_many(mm_cpumask(mm), tsb_sync, mm, 1);
905}
906
907extern unsigned long xcall_flush_tlb_mm;
908extern unsigned long xcall_flush_tlb_page;
909extern unsigned long xcall_flush_tlb_kernel_range;
910extern unsigned long xcall_fetch_glob_regs;
911extern unsigned long xcall_fetch_glob_pmu;
912extern unsigned long xcall_fetch_glob_pmu_n4;
913extern unsigned long xcall_receive_signal;
914extern unsigned long xcall_new_mmu_context_version;
915#ifdef CONFIG_KGDB
916extern unsigned long xcall_kgdb_capture;
917#endif
918
919#ifdef DCACHE_ALIASING_POSSIBLE
920extern unsigned long xcall_flush_dcache_page_cheetah;
921#endif
922extern unsigned long xcall_flush_dcache_page_spitfire;
923
924static inline void __local_flush_dcache_folio(struct folio *folio)
925{
926	unsigned int i, nr = folio_nr_pages(folio);
927
928#ifdef DCACHE_ALIASING_POSSIBLE
929	for (i = 0; i < nr; i++)
930		__flush_dcache_page(folio_address(folio) + i * PAGE_SIZE,
931			    ((tlb_type == spitfire) &&
932			     folio_flush_mapping(folio) != NULL));
933#else
934	if (folio_flush_mapping(folio) != NULL &&
935	    tlb_type == spitfire) {
936		unsigned long pfn = folio_pfn(folio)
937		for (i = 0; i < nr; i++)
938			__flush_icache_page((pfn + i) * PAGE_SIZE);
939	}
940#endif
941}
942
943void smp_flush_dcache_folio_impl(struct folio *folio, int cpu)
944{
945	int this_cpu;
946
947	if (tlb_type == hypervisor)
948		return;
949
950#ifdef CONFIG_DEBUG_DCFLUSH
951	atomic_inc(&dcpage_flushes);
952#endif
953
954	this_cpu = get_cpu();
955
956	if (cpu == this_cpu) {
957		__local_flush_dcache_folio(folio);
958	} else if (cpu_online(cpu)) {
959		void *pg_addr = folio_address(folio);
960		u64 data0 = 0;
961
962		if (tlb_type == spitfire) {
963			data0 = ((u64)&xcall_flush_dcache_page_spitfire);
964			if (folio_flush_mapping(folio) != NULL)
965				data0 |= ((u64)1 << 32);
966		} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
967#ifdef DCACHE_ALIASING_POSSIBLE
968			data0 =	((u64)&xcall_flush_dcache_page_cheetah);
969#endif
970		}
971		if (data0) {
972			unsigned int i, nr = folio_nr_pages(folio);
973
974			for (i = 0; i < nr; i++) {
975				xcall_deliver(data0, __pa(pg_addr),
976					      (u64) pg_addr, cpumask_of(cpu));
977#ifdef CONFIG_DEBUG_DCFLUSH
978				atomic_inc(&dcpage_flushes_xcall);
979#endif
980				pg_addr += PAGE_SIZE;
981			}
982		}
983	}
984
985	put_cpu();
986}
987
988void flush_dcache_folio_all(struct mm_struct *mm, struct folio *folio)
989{
990	void *pg_addr;
991	u64 data0;
992
993	if (tlb_type == hypervisor)
994		return;
995
996	preempt_disable();
997
998#ifdef CONFIG_DEBUG_DCFLUSH
999	atomic_inc(&dcpage_flushes);
1000#endif
1001	data0 = 0;
1002	pg_addr = folio_address(folio);
1003	if (tlb_type == spitfire) {
1004		data0 = ((u64)&xcall_flush_dcache_page_spitfire);
1005		if (folio_flush_mapping(folio) != NULL)
1006			data0 |= ((u64)1 << 32);
1007	} else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
1008#ifdef DCACHE_ALIASING_POSSIBLE
1009		data0 = ((u64)&xcall_flush_dcache_page_cheetah);
1010#endif
1011	}
1012	if (data0) {
1013		unsigned int i, nr = folio_nr_pages(folio);
1014
1015		for (i = 0; i < nr; i++) {
1016			xcall_deliver(data0, __pa(pg_addr),
1017				      (u64) pg_addr, cpu_online_mask);
1018#ifdef CONFIG_DEBUG_DCFLUSH
1019			atomic_inc(&dcpage_flushes_xcall);
1020#endif
1021			pg_addr += PAGE_SIZE;
1022		}
1023	}
1024	__local_flush_dcache_folio(folio);
1025
1026	preempt_enable();
1027}
1028
1029#ifdef CONFIG_KGDB
1030void kgdb_roundup_cpus(void)
1031{
1032	smp_cross_call(&xcall_kgdb_capture, 0, 0, 0);
1033}
1034#endif
1035
1036void smp_fetch_global_regs(void)
1037{
1038	smp_cross_call(&xcall_fetch_glob_regs, 0, 0, 0);
1039}
1040
1041void smp_fetch_global_pmu(void)
1042{
1043	if (tlb_type == hypervisor &&
1044	    sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
1045		smp_cross_call(&xcall_fetch_glob_pmu_n4, 0, 0, 0);
1046	else
1047		smp_cross_call(&xcall_fetch_glob_pmu, 0, 0, 0);
1048}
1049
1050/* We know that the window frames of the user have been flushed
1051 * to the stack before we get here because all callers of us
1052 * are flush_tlb_*() routines, and these run after flush_cache_*()
1053 * which performs the flushw.
1054 *
1055 * mm->cpu_vm_mask is a bit mask of which cpus an address
1056 * space has (potentially) executed on, this is the heuristic
1057 * we use to limit cross calls.
1058 */
1059
1060/* This currently is only used by the hugetlb arch pre-fault
1061 * hook on UltraSPARC-III+ and later when changing the pagesize
1062 * bits of the context register for an address space.
1063 */
1064void smp_flush_tlb_mm(struct mm_struct *mm)
1065{
1066	u32 ctx = CTX_HWBITS(mm->context);
1067
1068	get_cpu();
1069
1070	smp_cross_call_masked(&xcall_flush_tlb_mm,
1071			      ctx, 0, 0,
1072			      mm_cpumask(mm));
1073
1074	__flush_tlb_mm(ctx, SECONDARY_CONTEXT);
1075
1076	put_cpu();
1077}
1078
1079struct tlb_pending_info {
1080	unsigned long ctx;
1081	unsigned long nr;
1082	unsigned long *vaddrs;
1083};
1084
1085static void tlb_pending_func(void *info)
1086{
1087	struct tlb_pending_info *t = info;
1088
1089	__flush_tlb_pending(t->ctx, t->nr, t->vaddrs);
1090}
1091
1092void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
1093{
1094	u32 ctx = CTX_HWBITS(mm->context);
1095	struct tlb_pending_info info;
1096
1097	get_cpu();
1098
1099	info.ctx = ctx;
1100	info.nr = nr;
1101	info.vaddrs = vaddrs;
1102
1103	smp_call_function_many(mm_cpumask(mm), tlb_pending_func,
1104			       &info, 1);
1105
1106	__flush_tlb_pending(ctx, nr, vaddrs);
1107
1108	put_cpu();
1109}
1110
1111void smp_flush_tlb_page(struct mm_struct *mm, unsigned long vaddr)
1112{
1113	unsigned long context = CTX_HWBITS(mm->context);
1114
1115	get_cpu();
1116
1117	smp_cross_call_masked(&xcall_flush_tlb_page,
1118			      context, vaddr, 0,
1119			      mm_cpumask(mm));
1120
1121	__flush_tlb_page(context, vaddr);
1122
1123	put_cpu();
1124}
1125
1126void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
1127{
1128	start &= PAGE_MASK;
1129	end    = PAGE_ALIGN(end);
1130	if (start != end) {
1131		smp_cross_call(&xcall_flush_tlb_kernel_range,
1132			       0, start, end);
1133
1134		__flush_tlb_kernel_range(start, end);
1135	}
1136}
1137
1138/* CPU capture. */
1139/* #define CAPTURE_DEBUG */
1140extern unsigned long xcall_capture;
1141
1142static atomic_t smp_capture_depth = ATOMIC_INIT(0);
1143static atomic_t smp_capture_registry = ATOMIC_INIT(0);
1144static unsigned long penguins_are_doing_time;
1145
1146void smp_capture(void)
1147{
1148	int result = atomic_add_return(1, &smp_capture_depth);
1149
1150	if (result == 1) {
1151		int ncpus = num_online_cpus();
1152
1153#ifdef CAPTURE_DEBUG
1154		printk("CPU[%d]: Sending penguins to jail...",
1155		       smp_processor_id());
1156#endif
1157		penguins_are_doing_time = 1;
1158		atomic_inc(&smp_capture_registry);
1159		smp_cross_call(&xcall_capture, 0, 0, 0);
1160		while (atomic_read(&smp_capture_registry) != ncpus)
1161			rmb();
1162#ifdef CAPTURE_DEBUG
1163		printk("done\n");
1164#endif
1165	}
1166}
1167
1168void smp_release(void)
1169{
1170	if (atomic_dec_and_test(&smp_capture_depth)) {
1171#ifdef CAPTURE_DEBUG
1172		printk("CPU[%d]: Giving pardon to "
1173		       "imprisoned penguins\n",
1174		       smp_processor_id());
1175#endif
1176		penguins_are_doing_time = 0;
1177		membar_safe("#StoreLoad");
1178		atomic_dec(&smp_capture_registry);
1179	}
1180}
1181
1182/* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE
1183 * set, so they can service tlb flush xcalls...
1184 */
1185extern void prom_world(int);
1186
1187void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs)
1188{
1189	clear_softint(1 << irq);
1190
1191	preempt_disable();
1192
1193	__asm__ __volatile__("flushw");
1194	prom_world(1);
1195	atomic_inc(&smp_capture_registry);
1196	membar_safe("#StoreLoad");
1197	while (penguins_are_doing_time)
1198		rmb();
1199	atomic_dec(&smp_capture_registry);
1200	prom_world(0);
1201
1202	preempt_enable();
1203}
1204
1205void __init smp_prepare_cpus(unsigned int max_cpus)
1206{
1207}
1208
1209void __init smp_setup_processor_id(void)
1210{
1211	if (tlb_type == spitfire)
1212		xcall_deliver_impl = spitfire_xcall_deliver;
1213	else if (tlb_type == cheetah || tlb_type == cheetah_plus)
1214		xcall_deliver_impl = cheetah_xcall_deliver;
1215	else
1216		xcall_deliver_impl = hypervisor_xcall_deliver;
1217}
1218
1219void __init smp_fill_in_cpu_possible_map(void)
1220{
1221	int possible_cpus = num_possible_cpus();
1222	int i;
1223
1224	if (possible_cpus > nr_cpu_ids)
1225		possible_cpus = nr_cpu_ids;
1226
1227	for (i = 0; i < possible_cpus; i++)
1228		set_cpu_possible(i, true);
1229	for (; i < NR_CPUS; i++)
1230		set_cpu_possible(i, false);
1231}
1232
1233void smp_fill_in_sib_core_maps(void)
1234{
1235	unsigned int i;
1236
1237	for_each_present_cpu(i) {
1238		unsigned int j;
1239
1240		cpumask_clear(&cpu_core_map[i]);
1241		if (cpu_data(i).core_id == 0) {
1242			cpumask_set_cpu(i, &cpu_core_map[i]);
1243			continue;
1244		}
1245
1246		for_each_present_cpu(j) {
1247			if (cpu_data(i).core_id ==
1248			    cpu_data(j).core_id)
1249				cpumask_set_cpu(j, &cpu_core_map[i]);
1250		}
1251	}
1252
1253	for_each_present_cpu(i)  {
1254		unsigned int j;
1255
1256		for_each_present_cpu(j)  {
1257			if (cpu_data(i).max_cache_id ==
1258			    cpu_data(j).max_cache_id)
1259				cpumask_set_cpu(j, &cpu_core_sib_cache_map[i]);
1260
1261			if (cpu_data(i).sock_id == cpu_data(j).sock_id)
1262				cpumask_set_cpu(j, &cpu_core_sib_map[i]);
1263		}
1264	}
1265
1266	for_each_present_cpu(i) {
1267		unsigned int j;
1268
1269		cpumask_clear(&per_cpu(cpu_sibling_map, i));
1270		if (cpu_data(i).proc_id == -1) {
1271			cpumask_set_cpu(i, &per_cpu(cpu_sibling_map, i));
1272			continue;
1273		}
1274
1275		for_each_present_cpu(j) {
1276			if (cpu_data(i).proc_id ==
1277			    cpu_data(j).proc_id)
1278				cpumask_set_cpu(j, &per_cpu(cpu_sibling_map, i));
1279		}
1280	}
1281}
1282
1283int __cpu_up(unsigned int cpu, struct task_struct *tidle)
1284{
1285	int ret = smp_boot_one_cpu(cpu, tidle);
1286
1287	if (!ret) {
1288		cpumask_set_cpu(cpu, &smp_commenced_mask);
1289		while (!cpu_online(cpu))
1290			mb();
1291		if (!cpu_online(cpu)) {
1292			ret = -ENODEV;
1293		} else {
1294			/* On SUN4V, writes to %tick and %stick are
1295			 * not allowed.
1296			 */
1297			if (tlb_type != hypervisor)
1298				smp_synchronize_one_tick(cpu);
1299		}
1300	}
1301	return ret;
1302}
1303
1304#ifdef CONFIG_HOTPLUG_CPU
1305void cpu_play_dead(void)
1306{
1307	int cpu = smp_processor_id();
1308	unsigned long pstate;
1309
1310	idle_task_exit();
1311
1312	if (tlb_type == hypervisor) {
1313		struct trap_per_cpu *tb = &trap_block[cpu];
1314
1315		sun4v_cpu_qconf(HV_CPU_QUEUE_CPU_MONDO,
1316				tb->cpu_mondo_pa, 0);
1317		sun4v_cpu_qconf(HV_CPU_QUEUE_DEVICE_MONDO,
1318				tb->dev_mondo_pa, 0);
1319		sun4v_cpu_qconf(HV_CPU_QUEUE_RES_ERROR,
1320				tb->resum_mondo_pa, 0);
1321		sun4v_cpu_qconf(HV_CPU_QUEUE_NONRES_ERROR,
1322				tb->nonresum_mondo_pa, 0);
1323	}
1324
1325	cpumask_clear_cpu(cpu, &smp_commenced_mask);
1326	membar_safe("#Sync");
1327
1328	local_irq_disable();
1329
1330	__asm__ __volatile__(
1331		"rdpr	%%pstate, %0\n\t"
1332		"wrpr	%0, %1, %%pstate"
1333		: "=r" (pstate)
1334		: "i" (PSTATE_IE));
1335
1336	while (1)
1337		barrier();
1338}
1339
1340int __cpu_disable(void)
1341{
1342	int cpu = smp_processor_id();
1343	cpuinfo_sparc *c;
1344	int i;
1345
1346	for_each_cpu(i, &cpu_core_map[cpu])
1347		cpumask_clear_cpu(cpu, &cpu_core_map[i]);
1348	cpumask_clear(&cpu_core_map[cpu]);
1349
1350	for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu))
1351		cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i));
1352	cpumask_clear(&per_cpu(cpu_sibling_map, cpu));
1353
1354	c = &cpu_data(cpu);
1355
1356	c->core_id = 0;
1357	c->proc_id = -1;
1358
1359	smp_wmb();
1360
1361	/* Make sure no interrupts point to this cpu.  */
1362	fixup_irqs();
1363
1364	local_irq_enable();
1365	mdelay(1);
1366	local_irq_disable();
1367
1368	set_cpu_online(cpu, false);
1369
1370	cpu_map_rebuild();
1371
1372	return 0;
1373}
1374
1375void __cpu_die(unsigned int cpu)
1376{
1377	int i;
1378
1379	for (i = 0; i < 100; i++) {
1380		smp_rmb();
1381		if (!cpumask_test_cpu(cpu, &smp_commenced_mask))
1382			break;
1383		msleep(100);
1384	}
1385	if (cpumask_test_cpu(cpu, &smp_commenced_mask)) {
1386		printk(KERN_ERR "CPU %u didn't die...\n", cpu);
1387	} else {
1388#if defined(CONFIG_SUN_LDOMS)
1389		unsigned long hv_err;
1390		int limit = 100;
1391
1392		do {
1393			hv_err = sun4v_cpu_stop(cpu);
1394			if (hv_err == HV_EOK) {
1395				set_cpu_present(cpu, false);
1396				break;
1397			}
1398		} while (--limit > 0);
1399		if (limit <= 0) {
1400			printk(KERN_ERR "sun4v_cpu_stop() fails err=%lu\n",
1401			       hv_err);
1402		}
1403#endif
1404	}
1405}
1406#endif
1407
1408void __init smp_cpus_done(unsigned int max_cpus)
1409{
1410}
1411
1412static void send_cpu_ipi(int cpu)
1413{
1414	xcall_deliver((u64) &xcall_receive_signal,
1415			0, 0, cpumask_of(cpu));
1416}
1417
1418void scheduler_poke(void)
1419{
1420	if (!cpu_poke)
1421		return;
1422
1423	if (!__this_cpu_read(poke))
1424		return;
1425
1426	__this_cpu_write(poke, false);
1427	set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1428}
1429
1430static unsigned long send_cpu_poke(int cpu)
1431{
1432	unsigned long hv_err;
1433
1434	per_cpu(poke, cpu) = true;
1435	hv_err = sun4v_cpu_poke(cpu);
1436	if (hv_err != HV_EOK) {
1437		per_cpu(poke, cpu) = false;
1438		pr_err_ratelimited("%s: sun4v_cpu_poke() fails err=%lu\n",
1439				    __func__, hv_err);
1440	}
1441
1442	return hv_err;
1443}
1444
1445void arch_smp_send_reschedule(int cpu)
1446{
1447	if (cpu == smp_processor_id()) {
1448		WARN_ON_ONCE(preemptible());
1449		set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1450		return;
1451	}
1452
1453	/* Use cpu poke to resume idle cpu if supported. */
1454	if (cpu_poke && idle_cpu(cpu)) {
1455		unsigned long ret;
1456
1457		ret = send_cpu_poke(cpu);
1458		if (ret == HV_EOK)
1459			return;
1460	}
1461
1462	/* Use IPI in following cases:
1463	 * - cpu poke not supported
1464	 * - cpu not idle
1465	 * - send_cpu_poke() returns with error
1466	 */
1467	send_cpu_ipi(cpu);
1468}
1469
1470void smp_init_cpu_poke(void)
1471{
1472	unsigned long major;
1473	unsigned long minor;
1474	int ret;
1475
1476	if (tlb_type != hypervisor)
1477		return;
1478
1479	ret = sun4v_hvapi_get(HV_GRP_CORE, &major, &minor);
1480	if (ret) {
1481		pr_debug("HV_GRP_CORE is not registered\n");
1482		return;
1483	}
1484
1485	if (major == 1 && minor >= 6) {
1486		/* CPU POKE is registered. */
1487		cpu_poke = true;
1488		return;
1489	}
1490
1491	pr_debug("CPU_POKE not supported\n");
1492}
1493
1494void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs)
1495{
1496	clear_softint(1 << irq);
1497	scheduler_ipi();
1498}
1499
1500static void stop_this_cpu(void *dummy)
1501{
1502	set_cpu_online(smp_processor_id(), false);
1503	prom_stopself();
1504}
1505
1506void smp_send_stop(void)
1507{
1508	int cpu;
1509
1510	if (tlb_type == hypervisor) {
1511		int this_cpu = smp_processor_id();
1512#ifdef CONFIG_SERIAL_SUNHV
1513		sunhv_migrate_hvcons_irq(this_cpu);
1514#endif
1515		for_each_online_cpu(cpu) {
1516			if (cpu == this_cpu)
1517				continue;
1518
1519			set_cpu_online(cpu, false);
1520#ifdef CONFIG_SUN_LDOMS
1521			if (ldom_domaining_enabled) {
1522				unsigned long hv_err;
1523				hv_err = sun4v_cpu_stop(cpu);
1524				if (hv_err)
1525					printk(KERN_ERR "sun4v_cpu_stop() "
1526					       "failed err=%lu\n", hv_err);
1527			} else
1528#endif
1529				prom_stopcpu_cpuid(cpu);
1530		}
1531	} else
1532		smp_call_function(stop_this_cpu, NULL, 0);
1533}
1534
1535static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
1536{
1537	if (cpu_to_node(from) == cpu_to_node(to))
1538		return LOCAL_DISTANCE;
1539	else
1540		return REMOTE_DISTANCE;
1541}
1542
1543static int __init pcpu_cpu_to_node(int cpu)
1544{
1545	return cpu_to_node(cpu);
1546}
1547
1548void __init setup_per_cpu_areas(void)
1549{
1550	unsigned long delta;
1551	unsigned int cpu;
1552	int rc = -EINVAL;
1553
1554	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
1555		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
1556					    PERCPU_DYNAMIC_RESERVE, 4 << 20,
1557					    pcpu_cpu_distance,
1558					    pcpu_cpu_to_node);
1559		if (rc)
1560			pr_warn("PERCPU: %s allocator failed (%d), "
1561				"falling back to page size\n",
1562				pcpu_fc_names[pcpu_chosen_fc], rc);
1563	}
1564	if (rc < 0)
1565		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
1566					   pcpu_cpu_to_node);
1567	if (rc < 0)
1568		panic("cannot initialize percpu area (err=%d)", rc);
1569
1570	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
1571	for_each_possible_cpu(cpu)
1572		__per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];
1573
1574	/* Setup %g5 for the boot cpu.  */
1575	__local_per_cpu_offset = __per_cpu_offset(smp_processor_id());
1576
1577	of_fill_in_cpu_data();
1578	if (tlb_type == hypervisor)
1579		mdesc_fill_in_cpu_data(cpu_all_mask);
1580}
1581