1 /* smp.c: Sparc64 SMP support.
3 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/sched.h>
10 #include <linux/pagemap.h>
11 #include <linux/threads.h>
12 #include <linux/smp.h>
13 #include <linux/smp_lock.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel_stat.h>
16 #include <linux/delay.h>
17 #include <linux/init.h>
18 #include <linux/spinlock.h>
20 #include <linux/seq_file.h>
21 #include <linux/cache.h>
22 #include <linux/jiffies.h>
23 #include <linux/profile.h>
24 #include <linux/bootmem.h>
27 #include <asm/ptrace.h>
28 #include <asm/atomic.h>
29 #include <asm/tlbflush.h>
30 #include <asm/mmu_context.h>
31 #include <asm/cpudata.h>
35 #include <asm/pgtable.h>
36 #include <asm/oplib.h>
37 #include <asm/uaccess.h>
38 #include <asm/timer.h>
39 #include <asm/starfire.h>
41 #include <asm/sections.h>
43 extern void calibrate_delay(void);
45 /* Please don't make this stuff initdata!!! --DaveM */
46 static unsigned char boot_cpu_id;
48 cpumask_t cpu_online_map __read_mostly = CPU_MASK_NONE;
49 cpumask_t phys_cpu_present_map __read_mostly = CPU_MASK_NONE;
50 cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly =
51 { [0 ... NR_CPUS-1] = CPU_MASK_NONE };
52 static cpumask_t smp_commenced_mask;
53 static cpumask_t cpu_callout_map;
55 void smp_info(struct seq_file *m)
59 seq_printf(m, "State:\n");
60 for (i = 0; i < NR_CPUS; i++) {
63 "CPU%d:\t\tonline\n", i);
67 void smp_bogo(struct seq_file *m)
71 for (i = 0; i < NR_CPUS; i++)
74 "Cpu%dBogo\t: %lu.%02lu\n"
75 "Cpu%dClkTck\t: %016lx\n",
76 i, cpu_data(i).udelay_val / (500000/HZ),
77 (cpu_data(i).udelay_val / (5000/HZ)) % 100,
78 i, cpu_data(i).clock_tick);
81 void __init smp_store_cpu_info(int id)
85 /* multiplier and counter set by
86 smp_setup_percpu_timer() */
87 cpu_data(id).udelay_val = loops_per_jiffy;
89 cpu_find_by_mid(id, &cpu_node);
90 cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
91 "clock-frequency", 0);
93 def = ((tlb_type == hypervisor) ? (8 * 1024) : (16 * 1024));
94 cpu_data(id).dcache_size = prom_getintdefault(cpu_node, "dcache-size",
98 cpu_data(id).dcache_line_size =
99 prom_getintdefault(cpu_node, "dcache-line-size", def);
102 cpu_data(id).icache_size = prom_getintdefault(cpu_node, "icache-size",
106 cpu_data(id).icache_line_size =
107 prom_getintdefault(cpu_node, "icache-line-size", def);
109 def = ((tlb_type == hypervisor) ?
112 cpu_data(id).ecache_size = prom_getintdefault(cpu_node, "ecache-size",
116 cpu_data(id).ecache_line_size =
117 prom_getintdefault(cpu_node, "ecache-line-size", def);
119 printk("CPU[%d]: Caches "
120 "D[sz(%d):line_sz(%d)] "
121 "I[sz(%d):line_sz(%d)] "
122 "E[sz(%d):line_sz(%d)]\n",
124 cpu_data(id).dcache_size, cpu_data(id).dcache_line_size,
125 cpu_data(id).icache_size, cpu_data(id).icache_line_size,
126 cpu_data(id).ecache_size, cpu_data(id).ecache_line_size);
129 static void smp_setup_percpu_timer(void);
131 static volatile unsigned long callin_flag = 0;
133 void __init smp_callin(void)
135 int cpuid = hard_smp_processor_id();
137 __local_per_cpu_offset = __per_cpu_offset(cpuid);
139 if (tlb_type == hypervisor)
140 sun4v_ktsb_register();
144 smp_setup_percpu_timer();
146 if (cheetah_pcache_forced_on)
147 cheetah_enable_pcache();
152 smp_store_cpu_info(cpuid);
154 __asm__ __volatile__("membar #Sync\n\t"
155 "flush %%g6" : : : "memory");
157 /* Clear this or we will die instantly when we
158 * schedule back to this idler...
160 current_thread_info()->new_child = 0;
162 /* Attach to the address space of init_task. */
163 atomic_inc(&init_mm.mm_count);
164 current->active_mm = &init_mm;
166 while (!cpu_isset(cpuid, smp_commenced_mask))
169 cpu_set(cpuid, cpu_online_map);
171 /* idle thread is expected to have preempt disabled */
177 printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
178 panic("SMP bolixed\n");
181 static unsigned long current_tick_offset __read_mostly;
183 /* This tick register synchronization scheme is taken entirely from
184 * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
186 * The only change I've made is to rework it so that the master
187 * initiates the synchonization instead of the slave. -DaveM
191 #define SLAVE (SMP_CACHE_BYTES/sizeof(unsigned long))
193 #define NUM_ROUNDS 64 /* magic value */
194 #define NUM_ITERS 5 /* likewise */
196 static DEFINE_SPINLOCK(itc_sync_lock);
197 static unsigned long go[SLAVE + 1];
199 #define DEBUG_TICK_SYNC 0
201 static inline long get_delta (long *rt, long *master)
203 unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
204 unsigned long tcenter, t0, t1, tm;
207 for (i = 0; i < NUM_ITERS; i++) {
208 t0 = tick_ops->get_tick();
211 while (!(tm = go[SLAVE]))
215 t1 = tick_ops->get_tick();
217 if (t1 - t0 < best_t1 - best_t0)
218 best_t0 = t0, best_t1 = t1, best_tm = tm;
221 *rt = best_t1 - best_t0;
222 *master = best_tm - best_t0;
224 /* average best_t0 and best_t1 without overflow: */
225 tcenter = (best_t0/2 + best_t1/2);
226 if (best_t0 % 2 + best_t1 % 2 == 2)
228 return tcenter - best_tm;
231 void smp_synchronize_tick_client(void)
233 long i, delta, adj, adjust_latency = 0, done = 0;
234 unsigned long flags, rt, master_time_stamp, bound;
237 long rt; /* roundtrip time */
238 long master; /* master's timestamp */
239 long diff; /* difference between midpoint and master's timestamp */
240 long lat; /* estimate of itc adjustment latency */
249 local_irq_save(flags);
251 for (i = 0; i < NUM_ROUNDS; i++) {
252 delta = get_delta(&rt, &master_time_stamp);
254 done = 1; /* let's lock on to this... */
260 adjust_latency += -delta;
261 adj = -delta + adjust_latency/4;
265 tick_ops->add_tick(adj, current_tick_offset);
269 t[i].master = master_time_stamp;
271 t[i].lat = adjust_latency/4;
275 local_irq_restore(flags);
278 for (i = 0; i < NUM_ROUNDS; i++)
279 printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
280 t[i].rt, t[i].master, t[i].diff, t[i].lat);
283 printk(KERN_INFO "CPU %d: synchronized TICK with master CPU (last diff %ld cycles,"
284 "maxerr %lu cycles)\n", smp_processor_id(), delta, rt);
287 static void smp_start_sync_tick_client(int cpu);
289 static void smp_synchronize_one_tick(int cpu)
291 unsigned long flags, i;
295 smp_start_sync_tick_client(cpu);
297 /* wait for client to be ready */
301 /* now let the client proceed into his loop */
305 spin_lock_irqsave(&itc_sync_lock, flags);
307 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
312 go[SLAVE] = tick_ops->get_tick();
316 spin_unlock_irqrestore(&itc_sync_lock, flags);
319 extern void sun4v_init_mondo_queues(int use_bootmem, int cpu, int alloc, int load);
321 extern unsigned long sparc64_cpu_startup;
323 /* The OBP cpu startup callback truncates the 3rd arg cookie to
324 * 32-bits (I think) so to be safe we have it read the pointer
325 * contained here so we work on >4GB machines. -DaveM
327 static struct thread_info *cpu_new_thread = NULL;
329 static int __devinit smp_boot_one_cpu(unsigned int cpu)
331 unsigned long entry =
332 (unsigned long)(&sparc64_cpu_startup);
333 unsigned long cookie =
334 (unsigned long)(&cpu_new_thread);
335 struct task_struct *p;
340 cpu_new_thread = task_thread_info(p);
341 cpu_set(cpu, cpu_callout_map);
343 if (tlb_type == hypervisor) {
344 /* Alloc the mondo queues, cpu will load them. */
345 sun4v_init_mondo_queues(0, cpu, 1, 0);
347 prom_startcpu_cpuid(cpu, entry, cookie);
351 cpu_find_by_mid(cpu, &cpu_node);
352 prom_startcpu(cpu_node, entry, cookie);
355 for (timeout = 0; timeout < 5000000; timeout++) {
364 printk("Processor %d is stuck.\n", cpu);
365 cpu_clear(cpu, cpu_callout_map);
368 cpu_new_thread = NULL;
373 static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
378 if (this_is_starfire) {
379 /* map to real upaid */
380 cpu = (((cpu & 0x3c) << 1) |
381 ((cpu & 0x40) >> 4) |
385 target = (cpu << 14) | 0x70;
387 /* Ok, this is the real Spitfire Errata #54.
388 * One must read back from a UDB internal register
389 * after writes to the UDB interrupt dispatch, but
390 * before the membar Sync for that write.
391 * So we use the high UDB control register (ASI 0x7f,
392 * ADDR 0x20) for the dummy read. -DaveM
395 __asm__ __volatile__(
396 "wrpr %1, %2, %%pstate\n\t"
397 "stxa %4, [%0] %3\n\t"
398 "stxa %5, [%0+%8] %3\n\t"
400 "stxa %6, [%0+%8] %3\n\t"
402 "stxa %%g0, [%7] %3\n\t"
405 "ldxa [%%g1] 0x7f, %%g0\n\t"
408 : "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
409 "r" (data0), "r" (data1), "r" (data2), "r" (target),
410 "r" (0x10), "0" (tmp)
413 /* NOTE: PSTATE_IE is still clear. */
416 __asm__ __volatile__("ldxa [%%g0] %1, %0"
418 : "i" (ASI_INTR_DISPATCH_STAT));
420 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
427 } while (result & 0x1);
428 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
431 printk("CPU[%d]: mondo stuckage result[%016lx]\n",
432 smp_processor_id(), result);
439 static __inline__ void spitfire_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
444 __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
445 for_each_cpu_mask(i, mask)
446 spitfire_xcall_helper(data0, data1, data2, pstate, i);
449 /* Cheetah now allows to send the whole 64-bytes of data in the interrupt
450 * packet, but we have no use for that. However we do take advantage of
451 * the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
453 static void cheetah_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
456 int nack_busy_id, is_jbus;
458 if (cpus_empty(mask))
461 /* Unfortunately, someone at Sun had the brilliant idea to make the
462 * busy/nack fields hard-coded by ITID number for this Ultra-III
463 * derivative processor.
465 __asm__ ("rdpr %%ver, %0" : "=r" (ver));
466 is_jbus = ((ver >> 32) == __JALAPENO_ID ||
467 (ver >> 32) == __SERRANO_ID);
469 __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
472 __asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
473 : : "r" (pstate), "i" (PSTATE_IE));
475 /* Setup the dispatch data registers. */
476 __asm__ __volatile__("stxa %0, [%3] %6\n\t"
477 "stxa %1, [%4] %6\n\t"
478 "stxa %2, [%5] %6\n\t"
481 : "r" (data0), "r" (data1), "r" (data2),
482 "r" (0x40), "r" (0x50), "r" (0x60),
489 for_each_cpu_mask(i, mask) {
490 u64 target = (i << 14) | 0x70;
493 target |= (nack_busy_id << 24);
494 __asm__ __volatile__(
495 "stxa %%g0, [%0] %1\n\t"
498 : "r" (target), "i" (ASI_INTR_W));
503 /* Now, poll for completion. */
508 stuck = 100000 * nack_busy_id;
510 __asm__ __volatile__("ldxa [%%g0] %1, %0"
511 : "=r" (dispatch_stat)
512 : "i" (ASI_INTR_DISPATCH_STAT));
513 if (dispatch_stat == 0UL) {
514 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
520 } while (dispatch_stat & 0x5555555555555555UL);
522 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
525 if ((dispatch_stat & ~(0x5555555555555555UL)) == 0) {
526 /* Busy bits will not clear, continue instead
527 * of freezing up on this cpu.
529 printk("CPU[%d]: mondo stuckage result[%016lx]\n",
530 smp_processor_id(), dispatch_stat);
532 int i, this_busy_nack = 0;
534 /* Delay some random time with interrupts enabled
535 * to prevent deadlock.
537 udelay(2 * nack_busy_id);
539 /* Clear out the mask bits for cpus which did not
542 for_each_cpu_mask(i, mask) {
546 check_mask = (0x2UL << (2*i));
548 check_mask = (0x2UL <<
550 if ((dispatch_stat & check_mask) == 0)
560 /* Multi-cpu list version. */
561 static void hypervisor_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
563 struct trap_per_cpu *tb;
566 cpumask_t error_mask;
567 unsigned long flags, status;
568 int cnt, retries, this_cpu, prev_sent, i;
570 /* We have to do this whole thing with interrupts fully disabled.
571 * Otherwise if we send an xcall from interrupt context it will
572 * corrupt both our mondo block and cpu list state.
574 * One consequence of this is that we cannot use timeout mechanisms
575 * that depend upon interrupts being delivered locally. So, for
576 * example, we cannot sample jiffies and expect it to advance.
578 * Fortunately, udelay() uses %stick/%tick so we can use that.
580 local_irq_save(flags);
582 this_cpu = smp_processor_id();
583 tb = &trap_block[this_cpu];
585 mondo = __va(tb->cpu_mondo_block_pa);
591 cpu_list = __va(tb->cpu_list_pa);
593 /* Setup the initial cpu list. */
595 for_each_cpu_mask(i, mask)
598 cpus_clear(error_mask);
602 int forward_progress, n_sent;
604 status = sun4v_cpu_mondo_send(cnt,
606 tb->cpu_mondo_block_pa);
608 /* HV_EOK means all cpus received the xcall, we're done. */
609 if (likely(status == HV_EOK))
612 /* First, see if we made any forward progress.
614 * The hypervisor indicates successful sends by setting
615 * cpu list entries to the value 0xffff.
618 for (i = 0; i < cnt; i++) {
619 if (likely(cpu_list[i] == 0xffff))
623 forward_progress = 0;
624 if (n_sent > prev_sent)
625 forward_progress = 1;
629 /* If we get a HV_ECPUERROR, then one or more of the cpus
630 * in the list are in error state. Use the cpu_state()
631 * hypervisor call to find out which cpus are in error state.
633 if (unlikely(status == HV_ECPUERROR)) {
634 for (i = 0; i < cnt; i++) {
642 err = sun4v_cpu_state(cpu);
644 err == HV_CPU_STATE_ERROR) {
645 cpu_list[i] = 0xffff;
646 cpu_set(cpu, error_mask);
649 } else if (unlikely(status != HV_EWOULDBLOCK))
650 goto fatal_mondo_error;
652 /* Don't bother rewriting the CPU list, just leave the
653 * 0xffff and non-0xffff entries in there and the
654 * hypervisor will do the right thing.
656 * Only advance timeout state if we didn't make any
659 if (unlikely(!forward_progress)) {
660 if (unlikely(++retries > 10000))
661 goto fatal_mondo_timeout;
663 /* Delay a little bit to let other cpus catch up
664 * on their cpu mondo queue work.
670 local_irq_restore(flags);
672 if (unlikely(!cpus_empty(error_mask)))
673 goto fatal_mondo_cpu_error;
677 fatal_mondo_cpu_error:
678 printk(KERN_CRIT "CPU[%d]: SUN4V mondo cpu error, some target cpus "
679 "were in error state\n",
681 printk(KERN_CRIT "CPU[%d]: Error mask [ ", this_cpu);
682 for_each_cpu_mask(i, error_mask)
688 local_irq_restore(flags);
689 printk(KERN_CRIT "CPU[%d]: SUN4V mondo timeout, no forward "
690 " progress after %d retries.\n",
692 goto dump_cpu_list_and_out;
695 local_irq_restore(flags);
696 printk(KERN_CRIT "CPU[%d]: Unexpected SUN4V mondo error %lu\n",
698 printk(KERN_CRIT "CPU[%d]: Args were cnt(%d) cpulist_pa(%lx) "
699 "mondo_block_pa(%lx)\n",
700 this_cpu, cnt, tb->cpu_list_pa, tb->cpu_mondo_block_pa);
702 dump_cpu_list_and_out:
703 printk(KERN_CRIT "CPU[%d]: CPU list [ ", this_cpu);
704 for (i = 0; i < cnt; i++)
705 printk("%u ", cpu_list[i]);
709 /* Send cross call to all processors mentioned in MASK
712 static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, cpumask_t mask)
714 u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
715 int this_cpu = get_cpu();
717 cpus_and(mask, mask, cpu_online_map);
718 cpu_clear(this_cpu, mask);
720 if (tlb_type == spitfire)
721 spitfire_xcall_deliver(data0, data1, data2, mask);
722 else if (tlb_type == cheetah || tlb_type == cheetah_plus)
723 cheetah_xcall_deliver(data0, data1, data2, mask);
725 hypervisor_xcall_deliver(data0, data1, data2, mask);
726 /* NOTE: Caller runs local copy on master. */
731 extern unsigned long xcall_sync_tick;
733 static void smp_start_sync_tick_client(int cpu)
735 cpumask_t mask = cpumask_of_cpu(cpu);
737 smp_cross_call_masked(&xcall_sync_tick,
741 /* Send cross call to all processors except self. */
742 #define smp_cross_call(func, ctx, data1, data2) \
743 smp_cross_call_masked(func, ctx, data1, data2, cpu_online_map)
745 struct call_data_struct {
746 void (*func) (void *info);
752 static DEFINE_SPINLOCK(call_lock);
753 static struct call_data_struct *call_data;
755 extern unsigned long xcall_call_function;
758 * You must not call this function with disabled interrupts or from a
759 * hardware interrupt handler or from a bottom half handler.
761 static int smp_call_function_mask(void (*func)(void *info), void *info,
762 int nonatomic, int wait, cpumask_t mask)
764 struct call_data_struct data;
768 /* Can deadlock when called with interrupts disabled */
769 WARN_ON(irqs_disabled());
773 atomic_set(&data.finished, 0);
776 spin_lock(&call_lock);
778 cpu_clear(smp_processor_id(), mask);
779 cpus = cpus_weight(mask);
785 smp_cross_call_masked(&xcall_call_function, 0, 0, 0, mask);
788 * Wait for other cpus to complete function or at
789 * least snap the call data.
792 while (atomic_read(&data.finished) != cpus) {
800 spin_unlock(&call_lock);
805 spin_unlock(&call_lock);
806 printk("XCALL: Remote cpus not responding, ncpus=%d finished=%d\n",
807 cpus, atomic_read(&data.finished));
811 int smp_call_function(void (*func)(void *info), void *info,
812 int nonatomic, int wait)
814 return smp_call_function_mask(func, info, nonatomic, wait,
818 void smp_call_function_client(int irq, struct pt_regs *regs)
820 void (*func) (void *info) = call_data->func;
821 void *info = call_data->info;
823 clear_softint(1 << irq);
824 if (call_data->wait) {
825 /* let initiator proceed only after completion */
827 atomic_inc(&call_data->finished);
829 /* let initiator proceed after getting data */
830 atomic_inc(&call_data->finished);
835 static void tsb_sync(void *info)
837 struct mm_struct *mm = info;
839 if (current->active_mm == mm)
840 tsb_context_switch(mm);
843 void smp_tsb_sync(struct mm_struct *mm)
845 smp_call_function_mask(tsb_sync, mm, 0, 1, mm->cpu_vm_mask);
848 extern unsigned long xcall_flush_tlb_mm;
849 extern unsigned long xcall_flush_tlb_pending;
850 extern unsigned long xcall_flush_tlb_kernel_range;
851 extern unsigned long xcall_report_regs;
852 extern unsigned long xcall_receive_signal;
853 extern unsigned long xcall_new_mmu_context_version;
855 #ifdef DCACHE_ALIASING_POSSIBLE
856 extern unsigned long xcall_flush_dcache_page_cheetah;
858 extern unsigned long xcall_flush_dcache_page_spitfire;
860 #ifdef CONFIG_DEBUG_DCFLUSH
861 extern atomic_t dcpage_flushes;
862 extern atomic_t dcpage_flushes_xcall;
865 static __inline__ void __local_flush_dcache_page(struct page *page)
867 #ifdef DCACHE_ALIASING_POSSIBLE
868 __flush_dcache_page(page_address(page),
869 ((tlb_type == spitfire) &&
870 page_mapping(page) != NULL));
872 if (page_mapping(page) != NULL &&
873 tlb_type == spitfire)
874 __flush_icache_page(__pa(page_address(page)));
878 void smp_flush_dcache_page_impl(struct page *page, int cpu)
880 cpumask_t mask = cpumask_of_cpu(cpu);
883 if (tlb_type == hypervisor)
886 #ifdef CONFIG_DEBUG_DCFLUSH
887 atomic_inc(&dcpage_flushes);
890 this_cpu = get_cpu();
892 if (cpu == this_cpu) {
893 __local_flush_dcache_page(page);
894 } else if (cpu_online(cpu)) {
895 void *pg_addr = page_address(page);
898 if (tlb_type == spitfire) {
900 ((u64)&xcall_flush_dcache_page_spitfire);
901 if (page_mapping(page) != NULL)
902 data0 |= ((u64)1 << 32);
903 spitfire_xcall_deliver(data0,
907 } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
908 #ifdef DCACHE_ALIASING_POSSIBLE
910 ((u64)&xcall_flush_dcache_page_cheetah);
911 cheetah_xcall_deliver(data0,
916 #ifdef CONFIG_DEBUG_DCFLUSH
917 atomic_inc(&dcpage_flushes_xcall);
924 void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
926 void *pg_addr = page_address(page);
927 cpumask_t mask = cpu_online_map;
931 if (tlb_type == hypervisor)
934 this_cpu = get_cpu();
936 cpu_clear(this_cpu, mask);
938 #ifdef CONFIG_DEBUG_DCFLUSH
939 atomic_inc(&dcpage_flushes);
941 if (cpus_empty(mask))
943 if (tlb_type == spitfire) {
944 data0 = ((u64)&xcall_flush_dcache_page_spitfire);
945 if (page_mapping(page) != NULL)
946 data0 |= ((u64)1 << 32);
947 spitfire_xcall_deliver(data0,
951 } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
952 #ifdef DCACHE_ALIASING_POSSIBLE
953 data0 = ((u64)&xcall_flush_dcache_page_cheetah);
954 cheetah_xcall_deliver(data0,
959 #ifdef CONFIG_DEBUG_DCFLUSH
960 atomic_inc(&dcpage_flushes_xcall);
963 __local_flush_dcache_page(page);
968 static void __smp_receive_signal_mask(cpumask_t mask)
970 smp_cross_call_masked(&xcall_receive_signal, 0, 0, 0, mask);
973 void smp_receive_signal(int cpu)
975 cpumask_t mask = cpumask_of_cpu(cpu);
978 __smp_receive_signal_mask(mask);
981 void smp_receive_signal_client(int irq, struct pt_regs *regs)
983 clear_softint(1 << irq);
986 void smp_new_mmu_context_version_client(int irq, struct pt_regs *regs)
988 struct mm_struct *mm;
991 clear_softint(1 << irq);
993 /* See if we need to allocate a new TLB context because
994 * the version of the one we are using is now out of date.
996 mm = current->active_mm;
997 if (unlikely(!mm || (mm == &init_mm)))
1000 spin_lock_irqsave(&mm->context.lock, flags);
1002 if (unlikely(!CTX_VALID(mm->context)))
1003 get_new_mmu_context(mm);
1005 spin_unlock_irqrestore(&mm->context.lock, flags);
1007 load_secondary_context(mm);
1008 __flush_tlb_mm(CTX_HWBITS(mm->context),
1012 void smp_new_mmu_context_version(void)
1014 smp_cross_call(&xcall_new_mmu_context_version, 0, 0, 0);
1017 void smp_report_regs(void)
1019 smp_cross_call(&xcall_report_regs, 0, 0, 0);
1022 /* We know that the window frames of the user have been flushed
1023 * to the stack before we get here because all callers of us
1024 * are flush_tlb_*() routines, and these run after flush_cache_*()
1025 * which performs the flushw.
1027 * The SMP TLB coherency scheme we use works as follows:
1029 * 1) mm->cpu_vm_mask is a bit mask of which cpus an address
1030 * space has (potentially) executed on, this is the heuristic
1031 * we use to avoid doing cross calls.
1033 * Also, for flushing from kswapd and also for clones, we
1034 * use cpu_vm_mask as the list of cpus to make run the TLB.
1036 * 2) TLB context numbers are shared globally across all processors
1037 * in the system, this allows us to play several games to avoid
1040 * One invariant is that when a cpu switches to a process, and
1041 * that processes tsk->active_mm->cpu_vm_mask does not have the
1042 * current cpu's bit set, that tlb context is flushed locally.
1044 * If the address space is non-shared (ie. mm->count == 1) we avoid
1045 * cross calls when we want to flush the currently running process's
1046 * tlb state. This is done by clearing all cpu bits except the current
1047 * processor's in current->active_mm->cpu_vm_mask and performing the
1048 * flush locally only. This will force any subsequent cpus which run
1049 * this task to flush the context from the local tlb if the process
1050 * migrates to another cpu (again).
1052 * 3) For shared address spaces (threads) and swapping we bite the
1053 * bullet for most cases and perform the cross call (but only to
1054 * the cpus listed in cpu_vm_mask).
1056 * The performance gain from "optimizing" away the cross call for threads is
1057 * questionable (in theory the big win for threads is the massive sharing of
1058 * address space state across processors).
1061 /* This currently is only used by the hugetlb arch pre-fault
1062 * hook on UltraSPARC-III+ and later when changing the pagesize
1063 * bits of the context register for an address space.
1065 void smp_flush_tlb_mm(struct mm_struct *mm)
1067 u32 ctx = CTX_HWBITS(mm->context);
1068 int cpu = get_cpu();
1070 if (atomic_read(&mm->mm_users) == 1) {
1071 mm->cpu_vm_mask = cpumask_of_cpu(cpu);
1072 goto local_flush_and_out;
1075 smp_cross_call_masked(&xcall_flush_tlb_mm,
1079 local_flush_and_out:
1080 __flush_tlb_mm(ctx, SECONDARY_CONTEXT);
1085 void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
1087 u32 ctx = CTX_HWBITS(mm->context);
1088 int cpu = get_cpu();
1090 if (mm == current->active_mm && atomic_read(&mm->mm_users) == 1)
1091 mm->cpu_vm_mask = cpumask_of_cpu(cpu);
1093 smp_cross_call_masked(&xcall_flush_tlb_pending,
1094 ctx, nr, (unsigned long) vaddrs,
1097 __flush_tlb_pending(ctx, nr, vaddrs);
1102 void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
1105 end = PAGE_ALIGN(end);
1107 smp_cross_call(&xcall_flush_tlb_kernel_range,
1110 __flush_tlb_kernel_range(start, end);
1115 /* #define CAPTURE_DEBUG */
1116 extern unsigned long xcall_capture;
1118 static atomic_t smp_capture_depth = ATOMIC_INIT(0);
1119 static atomic_t smp_capture_registry = ATOMIC_INIT(0);
1120 static unsigned long penguins_are_doing_time;
1122 void smp_capture(void)
1124 int result = atomic_add_ret(1, &smp_capture_depth);
1127 int ncpus = num_online_cpus();
1129 #ifdef CAPTURE_DEBUG
1130 printk("CPU[%d]: Sending penguins to jail...",
1131 smp_processor_id());
1133 penguins_are_doing_time = 1;
1134 membar_storestore_loadstore();
1135 atomic_inc(&smp_capture_registry);
1136 smp_cross_call(&xcall_capture, 0, 0, 0);
1137 while (atomic_read(&smp_capture_registry) != ncpus)
1139 #ifdef CAPTURE_DEBUG
1145 void smp_release(void)
1147 if (atomic_dec_and_test(&smp_capture_depth)) {
1148 #ifdef CAPTURE_DEBUG
1149 printk("CPU[%d]: Giving pardon to "
1150 "imprisoned penguins\n",
1151 smp_processor_id());
1153 penguins_are_doing_time = 0;
1154 membar_storeload_storestore();
1155 atomic_dec(&smp_capture_registry);
1159 /* Imprisoned penguins run with %pil == 15, but PSTATE_IE set, so they
1160 * can service tlb flush xcalls...
1162 extern void prom_world(int);
1164 void smp_penguin_jailcell(int irq, struct pt_regs *regs)
1166 clear_softint(1 << irq);
1170 __asm__ __volatile__("flushw");
1172 atomic_inc(&smp_capture_registry);
1173 membar_storeload_storestore();
1174 while (penguins_are_doing_time)
1176 atomic_dec(&smp_capture_registry);
1182 #define prof_multiplier(__cpu) cpu_data(__cpu).multiplier
1183 #define prof_counter(__cpu) cpu_data(__cpu).counter
1185 void smp_percpu_timer_interrupt(struct pt_regs *regs)
1187 unsigned long compare, tick, pstate;
1188 int cpu = smp_processor_id();
1189 int user = user_mode(regs);
1192 * Check for level 14 softint.
1195 unsigned long tick_mask = tick_ops->softint_mask;
1197 if (!(get_softint() & tick_mask)) {
1198 extern void handler_irq(int, struct pt_regs *);
1200 handler_irq(14, regs);
1203 clear_softint(tick_mask);
1207 profile_tick(CPU_PROFILING, regs);
1208 if (!--prof_counter(cpu)) {
1211 if (cpu == boot_cpu_id) {
1212 kstat_this_cpu.irqs[0]++;
1213 timer_tick_interrupt(regs);
1216 update_process_times(user);
1220 prof_counter(cpu) = prof_multiplier(cpu);
1223 /* Guarantee that the following sequences execute
1226 __asm__ __volatile__("rdpr %%pstate, %0\n\t"
1227 "wrpr %0, %1, %%pstate"
1231 compare = tick_ops->add_compare(current_tick_offset);
1232 tick = tick_ops->get_tick();
1234 /* Restore PSTATE_IE. */
1235 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
1238 } while (time_after_eq(tick, compare));
1241 static void __init smp_setup_percpu_timer(void)
1243 int cpu = smp_processor_id();
1244 unsigned long pstate;
1246 prof_counter(cpu) = prof_multiplier(cpu) = 1;
1248 /* Guarantee that the following sequences execute
1251 __asm__ __volatile__("rdpr %%pstate, %0\n\t"
1252 "wrpr %0, %1, %%pstate"
1256 tick_ops->init_tick(current_tick_offset);
1258 /* Restore PSTATE_IE. */
1259 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
1264 void __init smp_tick_init(void)
1266 boot_cpu_id = hard_smp_processor_id();
1267 current_tick_offset = timer_tick_offset;
1269 cpu_set(boot_cpu_id, cpu_online_map);
1270 prof_counter(boot_cpu_id) = prof_multiplier(boot_cpu_id) = 1;
1273 /* /proc/profile writes can call this, don't __init it please. */
1274 static DEFINE_SPINLOCK(prof_setup_lock);
1276 int setup_profiling_timer(unsigned int multiplier)
1278 unsigned long flags;
1281 if ((!multiplier) || (timer_tick_offset / multiplier) < 1000)
1284 spin_lock_irqsave(&prof_setup_lock, flags);
1285 for (i = 0; i < NR_CPUS; i++)
1286 prof_multiplier(i) = multiplier;
1287 current_tick_offset = (timer_tick_offset / multiplier);
1288 spin_unlock_irqrestore(&prof_setup_lock, flags);
1293 /* Constrain the number of cpus to max_cpus. */
1294 void __init smp_prepare_cpus(unsigned int max_cpus)
1298 if (num_possible_cpus() > max_cpus) {
1302 while (!cpu_find_by_instance(instance, NULL, &mid)) {
1303 if (mid != boot_cpu_id) {
1304 cpu_clear(mid, phys_cpu_present_map);
1305 if (num_possible_cpus() <= max_cpus)
1313 if (tlb_type == hypervisor) {
1316 /* XXX get this mapping from machine description */
1318 if ((j >> 2) == (i >> 2))
1319 cpu_set(j, cpu_sibling_map[i]);
1322 cpu_set(i, cpu_sibling_map[i]);
1326 smp_store_cpu_info(boot_cpu_id);
1329 /* Set this up early so that things like the scheduler can init
1330 * properly. We use the same cpu mask for both the present and
1333 void __init smp_setup_cpu_possible_map(void)
1338 while (!cpu_find_by_instance(instance, NULL, &mid)) {
1340 cpu_set(mid, phys_cpu_present_map);
1345 void __devinit smp_prepare_boot_cpu(void)
1347 int cpu = hard_smp_processor_id();
1349 if (cpu >= NR_CPUS) {
1350 prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
1354 current_thread_info()->cpu = cpu;
1355 __local_per_cpu_offset = __per_cpu_offset(cpu);
1357 cpu_set(smp_processor_id(), cpu_online_map);
1358 cpu_set(smp_processor_id(), phys_cpu_present_map);
1361 int __devinit __cpu_up(unsigned int cpu)
1363 int ret = smp_boot_one_cpu(cpu);
1366 cpu_set(cpu, smp_commenced_mask);
1367 while (!cpu_isset(cpu, cpu_online_map))
1369 if (!cpu_isset(cpu, cpu_online_map)) {
1372 /* On SUN4V, writes to %tick and %stick are
1375 if (tlb_type != hypervisor)
1376 smp_synchronize_one_tick(cpu);
1382 void __init smp_cpus_done(unsigned int max_cpus)
1384 unsigned long bogosum = 0;
1387 for (i = 0; i < NR_CPUS; i++) {
1389 bogosum += cpu_data(i).udelay_val;
1391 printk("Total of %ld processors activated "
1392 "(%lu.%02lu BogoMIPS).\n",
1393 (long) num_online_cpus(),
1394 bogosum/(500000/HZ),
1395 (bogosum/(5000/HZ))%100);
1398 void smp_send_reschedule(int cpu)
1400 smp_receive_signal(cpu);
1403 /* This is a nop because we capture all other cpus
1404 * anyways when making the PROM active.
1406 void smp_send_stop(void)
1410 unsigned long __per_cpu_base __read_mostly;
1411 unsigned long __per_cpu_shift __read_mostly;
1413 EXPORT_SYMBOL(__per_cpu_base);
1414 EXPORT_SYMBOL(__per_cpu_shift);
1416 void __init setup_per_cpu_areas(void)
1418 unsigned long goal, size, i;
1421 /* Copy section for each CPU (we discard the original) */
1422 goal = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
1423 #ifdef CONFIG_MODULES
1424 if (goal < PERCPU_ENOUGH_ROOM)
1425 goal = PERCPU_ENOUGH_ROOM;
1427 __per_cpu_shift = 0;
1428 for (size = 1UL; size < goal; size <<= 1UL)
1431 ptr = alloc_bootmem(size * NR_CPUS);
1433 __per_cpu_base = ptr - __per_cpu_start;
1435 for (i = 0; i < NR_CPUS; i++, ptr += size)
1436 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);