arch/sparc/kernel/smp

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This source file includes following definitions.
smp_info
smp_bogo
smp_callin
cpu_panic
get_delta
smp_synchronize_tick_client
smp_synchronize_one_tick
ldom_startcpu_cpuid
smp_boot_one_cpu
spitfire_xcall_helper
spitfire_xcall_deliver
cheetah_xcall_deliver
hypervisor_xcall_deliver
xcall_deliver
smp_cross_call_masked
smp_cross_call
smp_start_sync_tick_client
arch_send_call_function_ipi_mask
arch_send_call_function_single_ipi
smp_call_function_client
smp_call_function_single_client
tsb_sync
smp_tsb_sync
__local_flush_dcache_page
smp_flush_dcache_page_impl
flush_dcache_page_all
kgdb_roundup_cpus
smp_fetch_global_regs
smp_fetch_global_pmu
smp_flush_tlb_mm
tlb_pending_func
smp_flush_tlb_pending
smp_flush_tlb_page
smp_flush_tlb_kernel_range
smp_capture
smp_release
smp_penguin_jailcell
setup_profiling_timer
smp_prepare_cpus
smp_prepare_boot_cpu
smp_setup_processor_id
smp_fill_in_cpu_possible_map
smp_fill_in_sib_core_maps
__cpu_up
cpu_play_dead
__cpu_disable
__cpu_die
smp_cpus_done
send_cpu_ipi
scheduler_poke
send_cpu_poke
smp_send_reschedule
smp_init_cpu_poke
smp_receive_signal_client
stop_this_cpu
smp_send_stop
pcpu_alloc_bootmem
pcpu_free_bootmem
pcpu_cpu_distance
pcpu_populate_pte
setup_per_cpu_areas
   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/pgtable.h>
  47 #include <asm/oplib.h>
  48 #include <linux/uaccess.h>
  49 #include <asm/starfire.h>
  50 #include <asm/tlb.h>
  51 #include <asm/sections.h>
  52 #include <asm/prom.h>
  53 #include <asm/mdesc.h>
  54 #include <asm/ldc.h>
  55 #include <asm/hypervisor.h>
  56 #include <asm/pcr.h>
  57 
  58 #include "cpumap.h"
  59 #include "kernel.h"
  60 
  61 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
  62 cpumask_t cpu_core_map[NR_CPUS] __read_mostly =
  63         { [0 ... NR_CPUS-1] = CPU_MASK_NONE };
  64 
  65 cpumask_t cpu_core_sib_map[NR_CPUS] __read_mostly = {
  66         [0 ... NR_CPUS-1] = CPU_MASK_NONE };
  67 
  68 cpumask_t cpu_core_sib_cache_map[NR_CPUS] __read_mostly = {
  69         [0 ... NR_CPUS - 1] = CPU_MASK_NONE };
  70 
  71 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
  72 EXPORT_SYMBOL(cpu_core_map);
  73 EXPORT_SYMBOL(cpu_core_sib_map);
  74 EXPORT_SYMBOL(cpu_core_sib_cache_map);
  75 
  76 static cpumask_t smp_commenced_mask;
  77 
  78 static DEFINE_PER_CPU(bool, poke);
  79 static bool cpu_poke;
  80 
  81 void smp_info(struct seq_file *m)
  82 {
  83         int i;
  84         
  85         seq_printf(m, "State:\n");
  86         for_each_online_cpu(i)
  87                 seq_printf(m, "CPU%d:\t\tonline\n", i);
  88 }
  89 
  90 void smp_bogo(struct seq_file *m)
  91 {
  92         int i;
  93         
  94         for_each_online_cpu(i)
  95                 seq_printf(m,
  96                            "Cpu%dClkTck\t: %016lx\n",
  97                            i, cpu_data(i).clock_tick);
  98 }
  99 
 100 extern void setup_sparc64_timer(void);
 101 
 102 static volatile unsigned long callin_flag = 0;
 103 
 104 void smp_callin(void)
 105 {
 106         int cpuid = hard_smp_processor_id();
 107 
 108         __local_per_cpu_offset = __per_cpu_offset(cpuid);
 109 
 110         if (tlb_type == hypervisor)
 111                 sun4v_ktsb_register();
 112 
 113         __flush_tlb_all();
 114 
 115         setup_sparc64_timer();
 116 
 117         if (cheetah_pcache_forced_on)
 118                 cheetah_enable_pcache();
 119 
 120         callin_flag = 1;
 121         __asm__ __volatile__("membar #Sync\n\t"
 122                              "flush  %%g6" : : : "memory");
 123 
 124         /* Clear this or we will die instantly when we
 125          * schedule back to this idler...
 126          */
 127         current_thread_info()->new_child = 0;
 128 
 129         /* Attach to the address space of init_task. */
 130         mmgrab(&init_mm);
 131         current->active_mm = &init_mm;
 132 
 133         /* inform the notifiers about the new cpu */
 134         notify_cpu_starting(cpuid);
 135 
 136         while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
 137                 rmb();
 138 
 139         set_cpu_online(cpuid, true);
 140 
 141         /* idle thread is expected to have preempt disabled */
 142         preempt_disable();
 143 
 144         local_irq_enable();
 145 
 146         cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 147 }
 148 
 149 void cpu_panic(void)
 150 {
 151         printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
 152         panic("SMP bolixed\n");
 153 }
 154 
 155 /* This tick register synchronization scheme is taken entirely from
 156  * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
 157  *
 158  * The only change I've made is to rework it so that the master
 159  * initiates the synchonization instead of the slave. -DaveM
 160  */
 161 
 162 #define MASTER  0
 163 #define SLAVE   (SMP_CACHE_BYTES/sizeof(unsigned long))
 164 
 165 #define NUM_ROUNDS      64      /* magic value */
 166 #define NUM_ITERS       5       /* likewise */
 167 
 168 static DEFINE_RAW_SPINLOCK(itc_sync_lock);
 169 static unsigned long go[SLAVE + 1];
 170 
 171 #define DEBUG_TICK_SYNC 0
 172 
 173 static inline long get_delta (long *rt, long *master)
 174 {
 175         unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
 176         unsigned long tcenter, t0, t1, tm;
 177         unsigned long i;
 178 
 179         for (i = 0; i < NUM_ITERS; i++) {
 180                 t0 = tick_ops->get_tick();
 181                 go[MASTER] = 1;
 182                 membar_safe("#StoreLoad");
 183                 while (!(tm = go[SLAVE]))
 184                         rmb();
 185                 go[SLAVE] = 0;
 186                 wmb();
 187                 t1 = tick_ops->get_tick();
 188 
 189                 if (t1 - t0 < best_t1 - best_t0)
 190                         best_t0 = t0, best_t1 = t1, best_tm = tm;
 191         }
 192 
 193         *rt = best_t1 - best_t0;
 194         *master = best_tm - best_t0;
 195 
 196         /* average best_t0 and best_t1 without overflow: */
 197         tcenter = (best_t0/2 + best_t1/2);
 198         if (best_t0 % 2 + best_t1 % 2 == 2)
 199                 tcenter++;
 200         return tcenter - best_tm;
 201 }
 202 
 203 void smp_synchronize_tick_client(void)
 204 {
 205         long i, delta, adj, adjust_latency = 0, done = 0;
 206         unsigned long flags, rt, master_time_stamp;
 207 #if DEBUG_TICK_SYNC
 208         struct {
 209                 long rt;        /* roundtrip time */
 210                 long master;    /* master's timestamp */
 211                 long diff;      /* difference between midpoint and master's timestamp */
 212                 long lat;       /* estimate of itc adjustment latency */
 213         } t[NUM_ROUNDS];
 214 #endif
 215 
 216         go[MASTER] = 1;
 217 
 218         while (go[MASTER])
 219                 rmb();
 220 
 221         local_irq_save(flags);
 222         {
 223                 for (i = 0; i < NUM_ROUNDS; i++) {
 224                         delta = get_delta(&rt, &master_time_stamp);
 225                         if (delta == 0)
 226                                 done = 1;       /* let's lock on to this... */
 227 
 228                         if (!done) {
 229                                 if (i > 0) {
 230                                         adjust_latency += -delta;
 231                                         adj = -delta + adjust_latency/4;
 232                                 } else
 233                                         adj = -delta;
 234 
 235                                 tick_ops->add_tick(adj);
 236                         }
 237 #if DEBUG_TICK_SYNC
 238                         t[i].rt = rt;
 239                         t[i].master = master_time_stamp;
 240                         t[i].diff = delta;
 241                         t[i].lat = adjust_latency/4;
 242 #endif
 243                 }
 244         }
 245         local_irq_restore(flags);
 246 
 247 #if DEBUG_TICK_SYNC
 248         for (i = 0; i < NUM_ROUNDS; i++)
 249                 printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
 250                        t[i].rt, t[i].master, t[i].diff, t[i].lat);
 251 #endif
 252 
 253         printk(KERN_INFO "CPU %d: synchronized TICK with master CPU "
 254                "(last diff %ld cycles, maxerr %lu cycles)\n",
 255                smp_processor_id(), delta, rt);
 256 }
 257 
 258 static void smp_start_sync_tick_client(int cpu);
 259 
 260 static void smp_synchronize_one_tick(int cpu)
 261 {
 262         unsigned long flags, i;
 263 
 264         go[MASTER] = 0;
 265 
 266         smp_start_sync_tick_client(cpu);
 267 
 268         /* wait for client to be ready */
 269         while (!go[MASTER])
 270                 rmb();
 271 
 272         /* now let the client proceed into his loop */
 273         go[MASTER] = 0;
 274         membar_safe("#StoreLoad");
 275 
 276         raw_spin_lock_irqsave(&itc_sync_lock, flags);
 277         {
 278                 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
 279                         while (!go[MASTER])
 280                                 rmb();
 281                         go[MASTER] = 0;
 282                         wmb();
 283                         go[SLAVE] = tick_ops->get_tick();
 284                         membar_safe("#StoreLoad");
 285                 }
 286         }
 287         raw_spin_unlock_irqrestore(&itc_sync_lock, flags);
 288 }
 289 
 290 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
 291 static void ldom_startcpu_cpuid(unsigned int cpu, unsigned long thread_reg,
 292                                 void **descrp)
 293 {
 294         extern unsigned long sparc64_ttable_tl0;
 295         extern unsigned long kern_locked_tte_data;
 296         struct hvtramp_descr *hdesc;
 297         unsigned long trampoline_ra;
 298         struct trap_per_cpu *tb;
 299         u64 tte_vaddr, tte_data;
 300         unsigned long hv_err;
 301         int i;
 302 
 303         hdesc = kzalloc(sizeof(*hdesc) +
 304                         (sizeof(struct hvtramp_mapping) *
 305                          num_kernel_image_mappings - 1),
 306                         GFP_KERNEL);
 307         if (!hdesc) {
 308                 printk(KERN_ERR "ldom_startcpu_cpuid: Cannot allocate "
 309                        "hvtramp_descr.\n");
 310                 return;
 311         }
 312         *descrp = hdesc;
 313 
 314         hdesc->cpu = cpu;
 315         hdesc->num_mappings = num_kernel_image_mappings;
 316 
 317         tb = &trap_block[cpu];
 318 
 319         hdesc->fault_info_va = (unsigned long) &tb->fault_info;
 320         hdesc->fault_info_pa = kimage_addr_to_ra(&tb->fault_info);
 321 
 322         hdesc->thread_reg = thread_reg;
 323 
 324         tte_vaddr = (unsigned long) KERNBASE;
 325         tte_data = kern_locked_tte_data;
 326 
 327         for (i = 0; i < hdesc->num_mappings; i++) {
 328                 hdesc->maps[i].vaddr = tte_vaddr;
 329                 hdesc->maps[i].tte   = tte_data;
 330                 tte_vaddr += 0x400000;
 331                 tte_data  += 0x400000;
 332         }
 333 
 334         trampoline_ra = kimage_addr_to_ra(hv_cpu_startup);
 335 
 336         hv_err = sun4v_cpu_start(cpu, trampoline_ra,
 337                                  kimage_addr_to_ra(&sparc64_ttable_tl0),
 338                                  __pa(hdesc));
 339         if (hv_err)
 340                 printk(KERN_ERR "ldom_startcpu_cpuid: sun4v_cpu_start() "
 341                        "gives error %lu\n", hv_err);
 342 }
 343 #endif
 344 
 345 extern unsigned long sparc64_cpu_startup;
 346 
 347 /* The OBP cpu startup callback truncates the 3rd arg cookie to
 348  * 32-bits (I think) so to be safe we have it read the pointer
 349  * contained here so we work on >4GB machines. -DaveM
 350  */
 351 static struct thread_info *cpu_new_thread = NULL;
 352 
 353 static int smp_boot_one_cpu(unsigned int cpu, struct task_struct *idle)
 354 {
 355         unsigned long entry =
 356                 (unsigned long)(&sparc64_cpu_startup);
 357         unsigned long cookie =
 358                 (unsigned long)(&cpu_new_thread);
 359         void *descr = NULL;
 360         int timeout, ret;
 361 
 362         callin_flag = 0;
 363         cpu_new_thread = task_thread_info(idle);
 364 
 365         if (tlb_type == hypervisor) {
 366 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
 367                 if (ldom_domaining_enabled)
 368                         ldom_startcpu_cpuid(cpu,
 369                                             (unsigned long) cpu_new_thread,
 370                                             &descr);
 371                 else
 372 #endif
 373                         prom_startcpu_cpuid(cpu, entry, cookie);
 374         } else {
 375                 struct device_node *dp = of_find_node_by_cpuid(cpu);
 376 
 377                 prom_startcpu(dp->phandle, entry, cookie);
 378         }
 379 
 380         for (timeout = 0; timeout < 50000; timeout++) {
 381                 if (callin_flag)
 382                         break;
 383                 udelay(100);
 384         }
 385 
 386         if (callin_flag) {
 387                 ret = 0;
 388         } else {
 389                 printk("Processor %d is stuck.\n", cpu);
 390                 ret = -ENODEV;
 391         }
 392         cpu_new_thread = NULL;
 393 
 394         kfree(descr);
 395 
 396         return ret;
 397 }
 398 
 399 static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
 400 {
 401         u64 result, target;
 402         int stuck, tmp;
 403 
 404         if (this_is_starfire) {
 405                 /* map to real upaid */
 406                 cpu = (((cpu & 0x3c) << 1) |
 407                         ((cpu & 0x40) >> 4) |
 408                         (cpu & 0x3));
 409         }
 410 
 411         target = (cpu << 14) | 0x70;
 412 again:
 413         /* Ok, this is the real Spitfire Errata #54.
 414          * One must read back from a UDB internal register
 415          * after writes to the UDB interrupt dispatch, but
 416          * before the membar Sync for that write.
 417          * So we use the high UDB control register (ASI 0x7f,
 418          * ADDR 0x20) for the dummy read. -DaveM
 419          */
 420         tmp = 0x40;
 421         __asm__ __volatile__(
 422         "wrpr   %1, %2, %%pstate\n\t"
 423         "stxa   %4, [%0] %3\n\t"
 424         "stxa   %5, [%0+%8] %3\n\t"
 425         "add    %0, %8, %0\n\t"
 426         "stxa   %6, [%0+%8] %3\n\t"
 427         "membar #Sync\n\t"
 428         "stxa   %%g0, [%7] %3\n\t"
 429         "membar #Sync\n\t"
 430         "mov    0x20, %%g1\n\t"
 431         "ldxa   [%%g1] 0x7f, %%g0\n\t"
 432         "membar #Sync"
 433         : "=r" (tmp)
 434         : "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
 435           "r" (data0), "r" (data1), "r" (data2), "r" (target),
 436           "r" (0x10), "0" (tmp)
 437         : "g1");
 438 
 439         /* NOTE: PSTATE_IE is still clear. */
 440         stuck = 100000;
 441         do {
 442                 __asm__ __volatile__("ldxa [%%g0] %1, %0"
 443                         : "=r" (result)
 444                         : "i" (ASI_INTR_DISPATCH_STAT));
 445                 if (result == 0) {
 446                         __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
 447                                              : : "r" (pstate));
 448                         return;
 449                 }
 450                 stuck -= 1;
 451                 if (stuck == 0)
 452                         break;
 453         } while (result & 0x1);
 454         __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
 455                              : : "r" (pstate));
 456         if (stuck == 0) {
 457                 printk("CPU[%d]: mondo stuckage result[%016llx]\n",
 458                        smp_processor_id(), result);
 459         } else {
 460                 udelay(2);
 461                 goto again;
 462         }
 463 }
 464 
 465 static void spitfire_xcall_deliver(struct trap_per_cpu *tb, int cnt)
 466 {
 467         u64 *mondo, data0, data1, data2;
 468         u16 *cpu_list;
 469         u64 pstate;
 470         int i;
 471 
 472         __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
 473         cpu_list = __va(tb->cpu_list_pa);
 474         mondo = __va(tb->cpu_mondo_block_pa);
 475         data0 = mondo[0];
 476         data1 = mondo[1];
 477         data2 = mondo[2];
 478         for (i = 0; i < cnt; i++)
 479                 spitfire_xcall_helper(data0, data1, data2, pstate, cpu_list[i]);
 480 }
 481 
 482 /* Cheetah now allows to send the whole 64-bytes of data in the interrupt
 483  * packet, but we have no use for that.  However we do take advantage of
 484  * the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
 485  */
 486 static void cheetah_xcall_deliver(struct trap_per_cpu *tb, int cnt)
 487 {
 488         int nack_busy_id, is_jbus, need_more;
 489         u64 *mondo, pstate, ver, busy_mask;
 490         u16 *cpu_list;
 491 
 492         cpu_list = __va(tb->cpu_list_pa);
 493         mondo = __va(tb->cpu_mondo_block_pa);
 494 
 495         /* Unfortunately, someone at Sun had the brilliant idea to make the
 496          * busy/nack fields hard-coded by ITID number for this Ultra-III
 497          * derivative processor.
 498          */
 499         __asm__ ("rdpr %%ver, %0" : "=r" (ver));
 500         is_jbus = ((ver >> 32) == __JALAPENO_ID ||
 501                    (ver >> 32) == __SERRANO_ID);
 502 
 503         __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
 504 
 505 retry:
 506         need_more = 0;
 507         __asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
 508                              : : "r" (pstate), "i" (PSTATE_IE));
 509 
 510         /* Setup the dispatch data registers. */
 511         __asm__ __volatile__("stxa      %0, [%3] %6\n\t"
 512                              "stxa      %1, [%4] %6\n\t"
 513                              "stxa      %2, [%5] %6\n\t"
 514                              "membar    #Sync\n\t"
 515                              : /* no outputs */
 516                              : "r" (mondo[0]), "r" (mondo[1]), "r" (mondo[2]),
 517                                "r" (0x40), "r" (0x50), "r" (0x60),
 518                                "i" (ASI_INTR_W));
 519 
 520         nack_busy_id = 0;
 521         busy_mask = 0;
 522         {
 523                 int i;
 524 
 525                 for (i = 0; i < cnt; i++) {
 526                         u64 target, nr;
 527 
 528                         nr = cpu_list[i];
 529                         if (nr == 0xffff)
 530                                 continue;
 531 
 532                         target = (nr << 14) | 0x70;
 533                         if (is_jbus) {
 534                                 busy_mask |= (0x1UL << (nr * 2));
 535                         } else {
 536                                 target |= (nack_busy_id << 24);
 537                                 busy_mask |= (0x1UL <<
 538                                               (nack_busy_id * 2));
 539                         }
 540                         __asm__ __volatile__(
 541                                 "stxa   %%g0, [%0] %1\n\t"
 542                                 "membar #Sync\n\t"
 543                                 : /* no outputs */
 544                                 : "r" (target), "i" (ASI_INTR_W));
 545                         nack_busy_id++;
 546                         if (nack_busy_id == 32) {
 547                                 need_more = 1;
 548                                 break;
 549                         }
 550                 }
 551         }
 552 
 553         /* Now, poll for completion. */
 554         {
 555                 u64 dispatch_stat, nack_mask;
 556                 long stuck;
 557 
 558                 stuck = 100000 * nack_busy_id;
 559                 nack_mask = busy_mask << 1;
 560                 do {
 561                         __asm__ __volatile__("ldxa      [%%g0] %1, %0"
 562                                              : "=r" (dispatch_stat)
 563                                              : "i" (ASI_INTR_DISPATCH_STAT));
 564                         if (!(dispatch_stat & (busy_mask | nack_mask))) {
 565                                 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
 566                                                      : : "r" (pstate));
 567                                 if (unlikely(need_more)) {
 568                                         int i, this_cnt = 0;
 569                                         for (i = 0; i < cnt; i++) {
 570                                                 if (cpu_list[i] == 0xffff)
 571                                                         continue;
 572                                                 cpu_list[i] = 0xffff;
 573                                                 this_cnt++;
 574                                                 if (this_cnt == 32)
 575                                                         break;
 576                                         }
 577                                         goto retry;
 578                                 }
 579                                 return;
 580                         }
 581                         if (!--stuck)
 582                                 break;
 583                 } while (dispatch_stat & busy_mask);
 584 
 585                 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
 586                                      : : "r" (pstate));
 587 
 588                 if (dispatch_stat & busy_mask) {
 589                         /* Busy bits will not clear, continue instead
 590                          * of freezing up on this cpu.
 591                          */
 592                         printk("CPU[%d]: mondo stuckage result[%016llx]\n",
 593                                smp_processor_id(), dispatch_stat);
 594                 } else {
 595                         int i, this_busy_nack = 0;
 596 
 597                         /* Delay some random time with interrupts enabled
 598                          * to prevent deadlock.
 599                          */
 600                         udelay(2 * nack_busy_id);
 601 
 602                         /* Clear out the mask bits for cpus which did not
 603                          * NACK us.
 604                          */
 605                         for (i = 0; i < cnt; i++) {
 606                                 u64 check_mask, nr;
 607 
 608                                 nr = cpu_list[i];
 609                                 if (nr == 0xffff)
 610                                         continue;
 611 
 612                                 if (is_jbus)
 613                                         check_mask = (0x2UL << (2*nr));
 614                                 else
 615                                         check_mask = (0x2UL <<
 616                                                       this_busy_nack);
 617                                 if ((dispatch_stat & check_mask) == 0)
 618                                         cpu_list[i] = 0xffff;
 619                                 this_busy_nack += 2;
 620                                 if (this_busy_nack == 64)
 621                                         break;
 622                         }
 623 
 624                         goto retry;
 625                 }
 626         }
 627 }
 628 
 629 #define CPU_MONDO_COUNTER(cpuid)        (cpu_mondo_counter[cpuid])
 630 #define MONDO_USEC_WAIT_MIN             2
 631 #define MONDO_USEC_WAIT_MAX             100
 632 #define MONDO_RETRY_LIMIT               500000
 633 
 634 /* Multi-cpu list version.
 635  *
 636  * Deliver xcalls to 'cnt' number of cpus in 'cpu_list'.
 637  * Sometimes not all cpus receive the mondo, requiring us to re-send
 638  * the mondo until all cpus have received, or cpus are truly stuck
 639  * unable to receive mondo, and we timeout.
 640  * Occasionally a target cpu strand is borrowed briefly by hypervisor to
 641  * perform guest service, such as PCIe error handling. Consider the
 642  * service time, 1 second overall wait is reasonable for 1 cpu.
 643  * Here two in-between mondo check wait time are defined: 2 usec for
 644  * single cpu quick turn around and up to 100usec for large cpu count.
 645  * Deliver mondo to large number of cpus could take longer, we adjusts
 646  * the retry count as long as target cpus are making forward progress.
 647  */
 648 static void hypervisor_xcall_deliver(struct trap_per_cpu *tb, int cnt)
 649 {
 650         int this_cpu, tot_cpus, prev_sent, i, rem;
 651         int usec_wait, retries, tot_retries;
 652         u16 first_cpu = 0xffff;
 653         unsigned long xc_rcvd = 0;
 654         unsigned long status;
 655         int ecpuerror_id = 0;
 656         int enocpu_id = 0;
 657         u16 *cpu_list;
 658         u16 cpu;
 659 
 660         this_cpu = smp_processor_id();
 661         cpu_list = __va(tb->cpu_list_pa);
 662         usec_wait = cnt * MONDO_USEC_WAIT_MIN;
 663         if (usec_wait > MONDO_USEC_WAIT_MAX)
 664                 usec_wait = MONDO_USEC_WAIT_MAX;
 665         retries = tot_retries = 0;
 666         tot_cpus = cnt;
 667         prev_sent = 0;
 668 
 669         do {
 670                 int n_sent, mondo_delivered, target_cpu_busy;
 671 
 672                 status = sun4v_cpu_mondo_send(cnt,
 673                                               tb->cpu_list_pa,
 674                                               tb->cpu_mondo_block_pa);
 675 
 676                 /* HV_EOK means all cpus received the xcall, we're done.  */
 677                 if (likely(status == HV_EOK))
 678                         goto xcall_done;
 679 
 680                 /* If not these non-fatal errors, panic */
 681                 if (unlikely((status != HV_EWOULDBLOCK) &&
 682                         (status != HV_ECPUERROR) &&
 683                         (status != HV_ENOCPU)))
 684                         goto fatal_errors;
 685 
 686                 /* First, see if we made any forward progress.
 687                  *
 688                  * Go through the cpu_list, count the target cpus that have
 689                  * received our mondo (n_sent), and those that did not (rem).
 690                  * Re-pack cpu_list with the cpus remain to be retried in the
 691                  * front - this simplifies tracking the truly stalled cpus.
 692                  *
 693                  * The hypervisor indicates successful sends by setting
 694                  * cpu list entries to the value 0xffff.
 695                  *
 696                  * EWOULDBLOCK means some target cpus did not receive the
 697                  * mondo and retry usually helps.
 698                  *
 699                  * ECPUERROR means at least one target cpu is in error state,
 700                  * it's usually safe to skip the faulty cpu and retry.
 701                  *
 702                  * ENOCPU means one of the target cpu doesn't belong to the
 703                  * domain, perhaps offlined which is unexpected, but not
 704                  * fatal and it's okay to skip the offlined cpu.
 705                  */
 706                 rem = 0;
 707                 n_sent = 0;
 708                 for (i = 0; i < cnt; i++) {
 709                         cpu = cpu_list[i];
 710                         if (likely(cpu == 0xffff)) {
 711                                 n_sent++;
 712                         } else if ((status == HV_ECPUERROR) &&
 713                                 (sun4v_cpu_state(cpu) == HV_CPU_STATE_ERROR)) {
 714                                 ecpuerror_id = cpu + 1;
 715                         } else if (status == HV_ENOCPU && !cpu_online(cpu)) {
 716                                 enocpu_id = cpu + 1;
 717                         } else {
 718                                 cpu_list[rem++] = cpu;
 719                         }
 720                 }
 721 
 722                 /* No cpu remained, we're done. */
 723                 if (rem == 0)
 724                         break;
 725 
 726                 /* Otherwise, update the cpu count for retry. */
 727                 cnt = rem;
 728 
 729                 /* Record the overall number of mondos received by the
 730                  * first of the remaining cpus.
 731                  */
 732                 if (first_cpu != cpu_list[0]) {
 733                         first_cpu = cpu_list[0];
 734                         xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
 735                 }
 736 
 737                 /* Was any mondo delivered successfully? */
 738                 mondo_delivered = (n_sent > prev_sent);
 739                 prev_sent = n_sent;
 740 
 741                 /* or, was any target cpu busy processing other mondos? */
 742                 target_cpu_busy = (xc_rcvd < CPU_MONDO_COUNTER(first_cpu));
 743                 xc_rcvd = CPU_MONDO_COUNTER(first_cpu);
 744 
 745                 /* Retry count is for no progress. If we're making progress,
 746                  * reset the retry count.
 747                  */
 748                 if (likely(mondo_delivered || target_cpu_busy)) {
 749                         tot_retries += retries;
 750                         retries = 0;
 751                 } else if (unlikely(retries > MONDO_RETRY_LIMIT)) {
 752                         goto fatal_mondo_timeout;
 753                 }
 754 
 755                 /* Delay a little bit to let other cpus catch up on
 756                  * their cpu mondo queue work.
 757                  */
 758                 if (!mondo_delivered)
 759                         udelay(usec_wait);
 760 
 761                 retries++;
 762         } while (1);
 763 
 764 xcall_done:
 765         if (unlikely(ecpuerror_id > 0)) {
 766                 pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) was in error state\n",
 767                        this_cpu, ecpuerror_id - 1);
 768         } else if (unlikely(enocpu_id > 0)) {
 769                 pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) does not belong to the domain\n",
 770                        this_cpu, enocpu_id - 1);
 771         }
 772         return;
 773 
 774 fatal_errors:
 775         /* fatal errors include bad alignment, etc */
 776         pr_crit("CPU[%d]: Args were cnt(%d) cpulist_pa(%lx) mondo_block_pa(%lx)\n",
 777                this_cpu, tot_cpus, tb->cpu_list_pa, tb->cpu_mondo_block_pa);
 778         panic("Unexpected SUN4V mondo error %lu\n", status);
 779 
 780 fatal_mondo_timeout:
 781         /* some cpus being non-responsive to the cpu mondo */
 782         pr_crit("CPU[%d]: SUN4V mondo timeout, cpu(%d) made no forward progress after %d retries. Total target cpus(%d).\n",
 783                this_cpu, first_cpu, (tot_retries + retries), tot_cpus);
 784         panic("SUN4V mondo timeout panic\n");
 785 }
 786 
 787 static void (*xcall_deliver_impl)(struct trap_per_cpu *, int);
 788 
 789 static void xcall_deliver(u64 data0, u64 data1, u64 data2, const cpumask_t *mask)
 790 {
 791         struct trap_per_cpu *tb;
 792         int this_cpu, i, cnt;
 793         unsigned long flags;
 794         u16 *cpu_list;
 795         u64 *mondo;
 796 
 797         /* We have to do this whole thing with interrupts fully disabled.
 798          * Otherwise if we send an xcall from interrupt context it will
 799          * corrupt both our mondo block and cpu list state.
 800          *
 801          * One consequence of this is that we cannot use timeout mechanisms
 802          * that depend upon interrupts being delivered locally.  So, for
 803          * example, we cannot sample jiffies and expect it to advance.
 804          *
 805          * Fortunately, udelay() uses %stick/%tick so we can use that.
 806          */
 807         local_irq_save(flags);
 808 
 809         this_cpu = smp_processor_id();
 810         tb = &trap_block[this_cpu];
 811 
 812         mondo = __va(tb->cpu_mondo_block_pa);
 813         mondo[0] = data0;
 814         mondo[1] = data1;
 815         mondo[2] = data2;
 816         wmb();
 817 
 818         cpu_list = __va(tb->cpu_list_pa);
 819 
 820         /* Setup the initial cpu list.  */
 821         cnt = 0;
 822         for_each_cpu(i, mask) {
 823                 if (i == this_cpu || !cpu_online(i))
 824                         continue;
 825                 cpu_list[cnt++] = i;
 826         }
 827 
 828         if (cnt)
 829                 xcall_deliver_impl(tb, cnt);
 830 
 831         local_irq_restore(flags);
 832 }
 833 
 834 /* Send cross call to all processors mentioned in MASK_P
 835  * except self.  Really, there are only two cases currently,
 836  * "cpu_online_mask" and "mm_cpumask(mm)".
 837  */
 838 static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, const cpumask_t *mask)
 839 {
 840         u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
 841 
 842         xcall_deliver(data0, data1, data2, mask);
 843 }
 844 
 845 /* Send cross call to all processors except self. */
 846 static void smp_cross_call(unsigned long *func, u32 ctx, u64 data1, u64 data2)
 847 {
 848         smp_cross_call_masked(func, ctx, data1, data2, cpu_online_mask);
 849 }
 850 
 851 extern unsigned long xcall_sync_tick;
 852 
 853 static void smp_start_sync_tick_client(int cpu)
 854 {
 855         xcall_deliver((u64) &xcall_sync_tick, 0, 0,
 856                       cpumask_of(cpu));
 857 }
 858 
 859 extern unsigned long xcall_call_function;
 860 
 861 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 862 {
 863         xcall_deliver((u64) &xcall_call_function, 0, 0, mask);
 864 }
 865 
 866 extern unsigned long xcall_call_function_single;
 867 
 868 void arch_send_call_function_single_ipi(int cpu)
 869 {
 870         xcall_deliver((u64) &xcall_call_function_single, 0, 0,
 871                       cpumask_of(cpu));
 872 }
 873 
 874 void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs)
 875 {
 876         clear_softint(1 << irq);
 877         irq_enter();
 878         generic_smp_call_function_interrupt();
 879         irq_exit();
 880 }
 881 
 882 void __irq_entry smp_call_function_single_client(int irq, struct pt_regs *regs)
 883 {
 884         clear_softint(1 << irq);
 885         irq_enter();
 886         generic_smp_call_function_single_interrupt();
 887         irq_exit();
 888 }
 889 
 890 static void tsb_sync(void *info)
 891 {
 892         struct trap_per_cpu *tp = &trap_block[raw_smp_processor_id()];
 893         struct mm_struct *mm = info;
 894 
 895         /* It is not valid to test "current->active_mm == mm" here.
 896          *
 897          * The value of "current" is not changed atomically with
 898          * switch_mm().  But that's OK, we just need to check the
 899          * current cpu's trap block PGD physical address.
 900          */
 901         if (tp->pgd_paddr == __pa(mm->pgd))
 902                 tsb_context_switch(mm);
 903 }
 904 
 905 void smp_tsb_sync(struct mm_struct *mm)
 906 {
 907         smp_call_function_many(mm_cpumask(mm), tsb_sync, mm, 1);
 908 }
 909 
 910 extern unsigned long xcall_flush_tlb_mm;
 911 extern unsigned long xcall_flush_tlb_page;
 912 extern unsigned long xcall_flush_tlb_kernel_range;
 913 extern unsigned long xcall_fetch_glob_regs;
 914 extern unsigned long xcall_fetch_glob_pmu;
 915 extern unsigned long xcall_fetch_glob_pmu_n4;
 916 extern unsigned long xcall_receive_signal;
 917 extern unsigned long xcall_new_mmu_context_version;
 918 #ifdef CONFIG_KGDB
 919 extern unsigned long xcall_kgdb_capture;
 920 #endif
 921 
 922 #ifdef DCACHE_ALIASING_POSSIBLE
 923 extern unsigned long xcall_flush_dcache_page_cheetah;
 924 #endif
 925 extern unsigned long xcall_flush_dcache_page_spitfire;
 926 
 927 static inline void __local_flush_dcache_page(struct page *page)
 928 {
 929 #ifdef DCACHE_ALIASING_POSSIBLE
 930         __flush_dcache_page(page_address(page),
 931                             ((tlb_type == spitfire) &&
 932                              page_mapping_file(page) != NULL));
 933 #else
 934         if (page_mapping_file(page) != NULL &&
 935             tlb_type == spitfire)
 936                 __flush_icache_page(__pa(page_address(page)));
 937 #endif
 938 }
 939 
 940 void smp_flush_dcache_page_impl(struct page *page, int cpu)
 941 {
 942         int this_cpu;
 943 
 944         if (tlb_type == hypervisor)
 945                 return;
 946 
 947 #ifdef CONFIG_DEBUG_DCFLUSH
 948         atomic_inc(&dcpage_flushes);
 949 #endif
 950 
 951         this_cpu = get_cpu();
 952 
 953         if (cpu == this_cpu) {
 954                 __local_flush_dcache_page(page);
 955         } else if (cpu_online(cpu)) {
 956                 void *pg_addr = page_address(page);
 957                 u64 data0 = 0;
 958 
 959                 if (tlb_type == spitfire) {
 960                         data0 = ((u64)&xcall_flush_dcache_page_spitfire);
 961                         if (page_mapping_file(page) != NULL)
 962                                 data0 |= ((u64)1 << 32);
 963                 } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
 964 #ifdef DCACHE_ALIASING_POSSIBLE
 965                         data0 = ((u64)&xcall_flush_dcache_page_cheetah);
 966 #endif
 967                 }
 968                 if (data0) {
 969                         xcall_deliver(data0, __pa(pg_addr),
 970                                       (u64) pg_addr, cpumask_of(cpu));
 971 #ifdef CONFIG_DEBUG_DCFLUSH
 972                         atomic_inc(&dcpage_flushes_xcall);
 973 #endif
 974                 }
 975         }
 976 
 977         put_cpu();
 978 }
 979 
 980 void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
 981 {
 982         void *pg_addr;
 983         u64 data0;
 984 
 985         if (tlb_type == hypervisor)
 986                 return;
 987 
 988         preempt_disable();
 989 
 990 #ifdef CONFIG_DEBUG_DCFLUSH
 991         atomic_inc(&dcpage_flushes);
 992 #endif
 993         data0 = 0;
 994         pg_addr = page_address(page);
 995         if (tlb_type == spitfire) {
 996                 data0 = ((u64)&xcall_flush_dcache_page_spitfire);
 997                 if (page_mapping_file(page) != NULL)
 998                         data0 |= ((u64)1 << 32);
 999         } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
1000 #ifdef DCACHE_ALIASING_POSSIBLE
1001                 data0 = ((u64)&xcall_flush_dcache_page_cheetah);
1002 #endif
1003         }
1004         if (data0) {
1005                 xcall_deliver(data0, __pa(pg_addr),
1006                               (u64) pg_addr, cpu_online_mask);
1007 #ifdef CONFIG_DEBUG_DCFLUSH
1008                 atomic_inc(&dcpage_flushes_xcall);
1009 #endif
1010         }
1011         __local_flush_dcache_page(page);
1012 
1013         preempt_enable();
1014 }
1015 
1016 #ifdef CONFIG_KGDB
1017 void kgdb_roundup_cpus(void)
1018 {
1019         smp_cross_call(&xcall_kgdb_capture, 0, 0, 0);
1020 }
1021 #endif
1022 
1023 void smp_fetch_global_regs(void)
1024 {
1025         smp_cross_call(&xcall_fetch_glob_regs, 0, 0, 0);
1026 }
1027 
1028 void smp_fetch_global_pmu(void)
1029 {
1030         if (tlb_type == hypervisor &&
1031             sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
1032                 smp_cross_call(&xcall_fetch_glob_pmu_n4, 0, 0, 0);
1033         else
1034                 smp_cross_call(&xcall_fetch_glob_pmu, 0, 0, 0);
1035 }
1036 
1037 /* We know that the window frames of the user have been flushed
1038  * to the stack before we get here because all callers of us
1039  * are flush_tlb_*() routines, and these run after flush_cache_*()
1040  * which performs the flushw.
1041  *
1042  * The SMP TLB coherency scheme we use works as follows:
1043  *
1044  * 1) mm->cpu_vm_mask is a bit mask of which cpus an address
1045  *    space has (potentially) executed on, this is the heuristic
1046  *    we use to avoid doing cross calls.
1047  *
1048  *    Also, for flushing from kswapd and also for clones, we
1049  *    use cpu_vm_mask as the list of cpus to make run the TLB.
1050  *
1051  * 2) TLB context numbers are shared globally across all processors
1052  *    in the system, this allows us to play several games to avoid
1053  *    cross calls.
1054  *
1055  *    One invariant is that when a cpu switches to a process, and
1056  *    that processes tsk->active_mm->cpu_vm_mask does not have the
1057  *    current cpu's bit set, that tlb context is flushed locally.
1058  *
1059  *    If the address space is non-shared (ie. mm->count == 1) we avoid
1060  *    cross calls when we want to flush the currently running process's
1061  *    tlb state.  This is done by clearing all cpu bits except the current
1062  *    processor's in current->mm->cpu_vm_mask and performing the
1063  *    flush locally only.  This will force any subsequent cpus which run
1064  *    this task to flush the context from the local tlb if the process
1065  *    migrates to another cpu (again).
1066  *
1067  * 3) For shared address spaces (threads) and swapping we bite the
1068  *    bullet for most cases and perform the cross call (but only to
1069  *    the cpus listed in cpu_vm_mask).
1070  *
1071  *    The performance gain from "optimizing" away the cross call for threads is
1072  *    questionable (in theory the big win for threads is the massive sharing of
1073  *    address space state across processors).
1074  */
1075 
1076 /* This currently is only used by the hugetlb arch pre-fault
1077  * hook on UltraSPARC-III+ and later when changing the pagesize
1078  * bits of the context register for an address space.
1079  */
1080 void smp_flush_tlb_mm(struct mm_struct *mm)
1081 {
1082         u32 ctx = CTX_HWBITS(mm->context);
1083         int cpu = get_cpu();
1084 
1085         if (atomic_read(&mm->mm_users) == 1) {
1086                 cpumask_copy(mm_cpumask(mm), cpumask_of(cpu));
1087                 goto local_flush_and_out;
1088         }
1089 
1090         smp_cross_call_masked(&xcall_flush_tlb_mm,
1091                               ctx, 0, 0,
1092                               mm_cpumask(mm));
1093 
1094 local_flush_and_out:
1095         __flush_tlb_mm(ctx, SECONDARY_CONTEXT);
1096 
1097         put_cpu();
1098 }
1099 
1100 struct tlb_pending_info {
1101         unsigned long ctx;
1102         unsigned long nr;
1103         unsigned long *vaddrs;
1104 };
1105 
1106 static void tlb_pending_func(void *info)
1107 {
1108         struct tlb_pending_info *t = info;
1109 
1110         __flush_tlb_pending(t->ctx, t->nr, t->vaddrs);
1111 }
1112 
1113 void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
1114 {
1115         u32 ctx = CTX_HWBITS(mm->context);
1116         struct tlb_pending_info info;
1117         int cpu = get_cpu();
1118 
1119         info.ctx = ctx;
1120         info.nr = nr;
1121         info.vaddrs = vaddrs;
1122 
1123         if (mm == current->mm && atomic_read(&mm->mm_users) == 1)
1124                 cpumask_copy(mm_cpumask(mm), cpumask_of(cpu));
1125         else
1126                 smp_call_function_many(mm_cpumask(mm), tlb_pending_func,
1127                                        &info, 1);
1128 
1129         __flush_tlb_pending(ctx, nr, vaddrs);
1130 
1131         put_cpu();
1132 }
1133 
1134 void smp_flush_tlb_page(struct mm_struct *mm, unsigned long vaddr)
1135 {
1136         unsigned long context = CTX_HWBITS(mm->context);
1137         int cpu = get_cpu();
1138 
1139         if (mm == current->mm && atomic_read(&mm->mm_users) == 1)
1140                 cpumask_copy(mm_cpumask(mm), cpumask_of(cpu));
1141         else
1142                 smp_cross_call_masked(&xcall_flush_tlb_page,
1143                                       context, vaddr, 0,
1144                                       mm_cpumask(mm));
1145         __flush_tlb_page(context, vaddr);
1146 
1147         put_cpu();
1148 }
1149 
1150 void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
1151 {
1152         start &= PAGE_MASK;
1153         end    = PAGE_ALIGN(end);
1154         if (start != end) {
1155                 smp_cross_call(&xcall_flush_tlb_kernel_range,
1156                                0, start, end);
1157 
1158                 __flush_tlb_kernel_range(start, end);
1159         }
1160 }
1161 
1162 /* CPU capture. */
1163 /* #define CAPTURE_DEBUG */
1164 extern unsigned long xcall_capture;
1165 
1166 static atomic_t smp_capture_depth = ATOMIC_INIT(0);
1167 static atomic_t smp_capture_registry = ATOMIC_INIT(0);
1168 static unsigned long penguins_are_doing_time;
1169 
1170 void smp_capture(void)
1171 {
1172         int result = atomic_add_return(1, &smp_capture_depth);
1173 
1174         if (result == 1) {
1175                 int ncpus = num_online_cpus();
1176 
1177 #ifdef CAPTURE_DEBUG
1178                 printk("CPU[%d]: Sending penguins to jail...",
1179                        smp_processor_id());
1180 #endif
1181                 penguins_are_doing_time = 1;
1182                 atomic_inc(&smp_capture_registry);
1183                 smp_cross_call(&xcall_capture, 0, 0, 0);
1184                 while (atomic_read(&smp_capture_registry) != ncpus)
1185                         rmb();
1186 #ifdef CAPTURE_DEBUG
1187                 printk("done\n");
1188 #endif
1189         }
1190 }
1191 
1192 void smp_release(void)
1193 {
1194         if (atomic_dec_and_test(&smp_capture_depth)) {
1195 #ifdef CAPTURE_DEBUG
1196                 printk("CPU[%d]: Giving pardon to "
1197                        "imprisoned penguins\n",
1198                        smp_processor_id());
1199 #endif
1200                 penguins_are_doing_time = 0;
1201                 membar_safe("#StoreLoad");
1202                 atomic_dec(&smp_capture_registry);
1203         }
1204 }
1205 
1206 /* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE
1207  * set, so they can service tlb flush xcalls...
1208  */
1209 extern void prom_world(int);
1210 
1211 void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs)
1212 {
1213         clear_softint(1 << irq);
1214 
1215         preempt_disable();
1216 
1217         __asm__ __volatile__("flushw");
1218         prom_world(1);
1219         atomic_inc(&smp_capture_registry);
1220         membar_safe("#StoreLoad");
1221         while (penguins_are_doing_time)
1222                 rmb();
1223         atomic_dec(&smp_capture_registry);
1224         prom_world(0);
1225 
1226         preempt_enable();
1227 }
1228 
1229 /* /proc/profile writes can call this, don't __init it please. */
1230 int setup_profiling_timer(unsigned int multiplier)
1231 {
1232         return -EINVAL;
1233 }
1234 
1235 void __init smp_prepare_cpus(unsigned int max_cpus)
1236 {
1237 }
1238 
1239 void smp_prepare_boot_cpu(void)
1240 {
1241 }
1242 
1243 void __init smp_setup_processor_id(void)
1244 {
1245         if (tlb_type == spitfire)
1246                 xcall_deliver_impl = spitfire_xcall_deliver;
1247         else if (tlb_type == cheetah || tlb_type == cheetah_plus)
1248                 xcall_deliver_impl = cheetah_xcall_deliver;
1249         else
1250                 xcall_deliver_impl = hypervisor_xcall_deliver;
1251 }
1252 
1253 void __init smp_fill_in_cpu_possible_map(void)
1254 {
1255         int possible_cpus = num_possible_cpus();
1256         int i;
1257 
1258         if (possible_cpus > nr_cpu_ids)
1259                 possible_cpus = nr_cpu_ids;
1260 
1261         for (i = 0; i < possible_cpus; i++)
1262                 set_cpu_possible(i, true);
1263         for (; i < NR_CPUS; i++)
1264                 set_cpu_possible(i, false);
1265 }
1266 
1267 void smp_fill_in_sib_core_maps(void)
1268 {
1269         unsigned int i;
1270 
1271         for_each_present_cpu(i) {
1272                 unsigned int j;
1273 
1274                 cpumask_clear(&cpu_core_map[i]);
1275                 if (cpu_data(i).core_id == 0) {
1276                         cpumask_set_cpu(i, &cpu_core_map[i]);
1277                         continue;
1278                 }
1279 
1280                 for_each_present_cpu(j) {
1281                         if (cpu_data(i).core_id ==
1282                             cpu_data(j).core_id)
1283                                 cpumask_set_cpu(j, &cpu_core_map[i]);
1284                 }
1285         }
1286 
1287         for_each_present_cpu(i)  {
1288                 unsigned int j;
1289 
1290                 for_each_present_cpu(j)  {
1291                         if (cpu_data(i).max_cache_id ==
1292                             cpu_data(j).max_cache_id)
1293                                 cpumask_set_cpu(j, &cpu_core_sib_cache_map[i]);
1294 
1295                         if (cpu_data(i).sock_id == cpu_data(j).sock_id)
1296                                 cpumask_set_cpu(j, &cpu_core_sib_map[i]);
1297                 }
1298         }
1299 
1300         for_each_present_cpu(i) {
1301                 unsigned int j;
1302 
1303                 cpumask_clear(&per_cpu(cpu_sibling_map, i));
1304                 if (cpu_data(i).proc_id == -1) {
1305                         cpumask_set_cpu(i, &per_cpu(cpu_sibling_map, i));
1306                         continue;
1307                 }
1308 
1309                 for_each_present_cpu(j) {
1310                         if (cpu_data(i).proc_id ==
1311                             cpu_data(j).proc_id)
1312                                 cpumask_set_cpu(j, &per_cpu(cpu_sibling_map, i));
1313                 }
1314         }
1315 }
1316 
1317 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
1318 {
1319         int ret = smp_boot_one_cpu(cpu, tidle);
1320 
1321         if (!ret) {
1322                 cpumask_set_cpu(cpu, &smp_commenced_mask);
1323                 while (!cpu_online(cpu))
1324                         mb();
1325                 if (!cpu_online(cpu)) {
1326                         ret = -ENODEV;
1327                 } else {
1328                         /* On SUN4V, writes to %tick and %stick are
1329                          * not allowed.
1330                          */
1331                         if (tlb_type != hypervisor)
1332                                 smp_synchronize_one_tick(cpu);
1333                 }
1334         }
1335         return ret;
1336 }
1337 
1338 #ifdef CONFIG_HOTPLUG_CPU
1339 void cpu_play_dead(void)
1340 {
1341         int cpu = smp_processor_id();
1342         unsigned long pstate;
1343 
1344         idle_task_exit();
1345 
1346         if (tlb_type == hypervisor) {
1347                 struct trap_per_cpu *tb = &trap_block[cpu];
1348 
1349                 sun4v_cpu_qconf(HV_CPU_QUEUE_CPU_MONDO,
1350                                 tb->cpu_mondo_pa, 0);
1351                 sun4v_cpu_qconf(HV_CPU_QUEUE_DEVICE_MONDO,
1352                                 tb->dev_mondo_pa, 0);
1353                 sun4v_cpu_qconf(HV_CPU_QUEUE_RES_ERROR,
1354                                 tb->resum_mondo_pa, 0);
1355                 sun4v_cpu_qconf(HV_CPU_QUEUE_NONRES_ERROR,
1356                                 tb->nonresum_mondo_pa, 0);
1357         }
1358 
1359         cpumask_clear_cpu(cpu, &smp_commenced_mask);
1360         membar_safe("#Sync");
1361 
1362         local_irq_disable();
1363 
1364         __asm__ __volatile__(
1365                 "rdpr   %%pstate, %0\n\t"
1366                 "wrpr   %0, %1, %%pstate"
1367                 : "=r" (pstate)
1368                 : "i" (PSTATE_IE));
1369 
1370         while (1)
1371                 barrier();
1372 }
1373 
1374 int __cpu_disable(void)
1375 {
1376         int cpu = smp_processor_id();
1377         cpuinfo_sparc *c;
1378         int i;
1379 
1380         for_each_cpu(i, &cpu_core_map[cpu])
1381                 cpumask_clear_cpu(cpu, &cpu_core_map[i]);
1382         cpumask_clear(&cpu_core_map[cpu]);
1383 
1384         for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu))
1385                 cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i));
1386         cpumask_clear(&per_cpu(cpu_sibling_map, cpu));
1387 
1388         c = &cpu_data(cpu);
1389 
1390         c->core_id = 0;
1391         c->proc_id = -1;
1392 
1393         smp_wmb();
1394 
1395         /* Make sure no interrupts point to this cpu.  */
1396         fixup_irqs();
1397 
1398         local_irq_enable();
1399         mdelay(1);
1400         local_irq_disable();
1401 
1402         set_cpu_online(cpu, false);
1403 
1404         cpu_map_rebuild();
1405 
1406         return 0;
1407 }
1408 
1409 void __cpu_die(unsigned int cpu)
1410 {
1411         int i;
1412 
1413         for (i = 0; i < 100; i++) {
1414                 smp_rmb();
1415                 if (!cpumask_test_cpu(cpu, &smp_commenced_mask))
1416                         break;
1417                 msleep(100);
1418         }
1419         if (cpumask_test_cpu(cpu, &smp_commenced_mask)) {
1420                 printk(KERN_ERR "CPU %u didn't die...\n", cpu);
1421         } else {
1422 #if defined(CONFIG_SUN_LDOMS)
1423                 unsigned long hv_err;
1424                 int limit = 100;
1425 
1426                 do {
1427                         hv_err = sun4v_cpu_stop(cpu);
1428                         if (hv_err == HV_EOK) {
1429                                 set_cpu_present(cpu, false);
1430                                 break;
1431                         }
1432                 } while (--limit > 0);
1433                 if (limit <= 0) {
1434                         printk(KERN_ERR "sun4v_cpu_stop() fails err=%lu\n",
1435                                hv_err);
1436                 }
1437 #endif
1438         }
1439 }
1440 #endif
1441 
1442 void __init smp_cpus_done(unsigned int max_cpus)
1443 {
1444 }
1445 
1446 static void send_cpu_ipi(int cpu)
1447 {
1448         xcall_deliver((u64) &xcall_receive_signal,
1449                         0, 0, cpumask_of(cpu));
1450 }
1451 
1452 void scheduler_poke(void)
1453 {
1454         if (!cpu_poke)
1455                 return;
1456 
1457         if (!__this_cpu_read(poke))
1458                 return;
1459 
1460         __this_cpu_write(poke, false);
1461         set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1462 }
1463 
1464 static unsigned long send_cpu_poke(int cpu)
1465 {
1466         unsigned long hv_err;
1467 
1468         per_cpu(poke, cpu) = true;
1469         hv_err = sun4v_cpu_poke(cpu);
1470         if (hv_err != HV_EOK) {
1471                 per_cpu(poke, cpu) = false;
1472                 pr_err_ratelimited("%s: sun4v_cpu_poke() fails err=%lu\n",
1473                                     __func__, hv_err);
1474         }
1475 
1476         return hv_err;
1477 }
1478 
1479 void smp_send_reschedule(int cpu)
1480 {
1481         if (cpu == smp_processor_id()) {
1482                 WARN_ON_ONCE(preemptible());
1483                 set_softint(1 << PIL_SMP_RECEIVE_SIGNAL);
1484                 return;
1485         }
1486 
1487         /* Use cpu poke to resume idle cpu if supported. */
1488         if (cpu_poke && idle_cpu(cpu)) {
1489                 unsigned long ret;
1490 
1491                 ret = send_cpu_poke(cpu);
1492                 if (ret == HV_EOK)
1493                         return;
1494         }
1495 
1496         /* Use IPI in following cases:
1497          * - cpu poke not supported
1498          * - cpu not idle
1499          * - send_cpu_poke() returns with error
1500          */
1501         send_cpu_ipi(cpu);
1502 }
1503 
1504 void smp_init_cpu_poke(void)
1505 {
1506         unsigned long major;
1507         unsigned long minor;
1508         int ret;
1509 
1510         if (tlb_type != hypervisor)
1511                 return;
1512 
1513         ret = sun4v_hvapi_get(HV_GRP_CORE, &major, &minor);
1514         if (ret) {
1515                 pr_debug("HV_GRP_CORE is not registered\n");
1516                 return;
1517         }
1518 
1519         if (major == 1 && minor >= 6) {
1520                 /* CPU POKE is registered. */
1521                 cpu_poke = true;
1522                 return;
1523         }
1524 
1525         pr_debug("CPU_POKE not supported\n");
1526 }
1527 
1528 void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs)
1529 {
1530         clear_softint(1 << irq);
1531         scheduler_ipi();
1532 }
1533 
1534 static void stop_this_cpu(void *dummy)
1535 {
1536         set_cpu_online(smp_processor_id(), false);
1537         prom_stopself();
1538 }
1539 
1540 void smp_send_stop(void)
1541 {
1542         int cpu;
1543 
1544         if (tlb_type == hypervisor) {
1545                 int this_cpu = smp_processor_id();
1546 #ifdef CONFIG_SERIAL_SUNHV
1547                 sunhv_migrate_hvcons_irq(this_cpu);
1548 #endif
1549                 for_each_online_cpu(cpu) {
1550                         if (cpu == this_cpu)
1551                                 continue;
1552 
1553                         set_cpu_online(cpu, false);
1554 #ifdef CONFIG_SUN_LDOMS
1555                         if (ldom_domaining_enabled) {
1556                                 unsigned long hv_err;
1557                                 hv_err = sun4v_cpu_stop(cpu);
1558                                 if (hv_err)
1559                                         printk(KERN_ERR "sun4v_cpu_stop() "
1560                                                "failed err=%lu\n", hv_err);
1561                         } else
1562 #endif
1563                                 prom_stopcpu_cpuid(cpu);
1564                 }
1565         } else
1566                 smp_call_function(stop_this_cpu, NULL, 0);
1567 }
1568 
1569 /**
1570  * pcpu_alloc_bootmem - NUMA friendly alloc_bootmem wrapper for percpu
1571  * @cpu: cpu to allocate for
1572  * @size: size allocation in bytes
1573  * @align: alignment
1574  *
1575  * Allocate @size bytes aligned at @align for cpu @cpu.  This wrapper
1576  * does the right thing for NUMA regardless of the current
1577  * configuration.
1578  *
1579  * RETURNS:
1580  * Pointer to the allocated area on success, NULL on failure.
1581  */
1582 static void * __init pcpu_alloc_bootmem(unsigned int cpu, size_t size,
1583                                         size_t align)
1584 {
1585         const unsigned long goal = __pa(MAX_DMA_ADDRESS);
1586 #ifdef CONFIG_NEED_MULTIPLE_NODES
1587         int node = cpu_to_node(cpu);
1588         void *ptr;
1589 
1590         if (!node_online(node) || !NODE_DATA(node)) {
1591                 ptr = memblock_alloc_from(size, align, goal);
1592                 pr_info("cpu %d has no node %d or node-local memory\n",
1593                         cpu, node);
1594                 pr_debug("per cpu data for cpu%d %lu bytes at %016lx\n",
1595                          cpu, size, __pa(ptr));
1596         } else {
1597                 ptr = memblock_alloc_try_nid(size, align, goal,
1598                                              MEMBLOCK_ALLOC_ACCESSIBLE, node);
1599                 pr_debug("per cpu data for cpu%d %lu bytes on node%d at "
1600                          "%016lx\n", cpu, size, node, __pa(ptr));
1601         }
1602         return ptr;
1603 #else
1604         return memblock_alloc_from(size, align, goal);
1605 #endif
1606 }
1607 
1608 static void __init pcpu_free_bootmem(void *ptr, size_t size)
1609 {
1610         memblock_free(__pa(ptr), size);
1611 }
1612 
1613 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
1614 {
1615         if (cpu_to_node(from) == cpu_to_node(to))
1616                 return LOCAL_DISTANCE;
1617         else
1618                 return REMOTE_DISTANCE;
1619 }
1620 
1621 static void __init pcpu_populate_pte(unsigned long addr)
1622 {
1623         pgd_t *pgd = pgd_offset_k(addr);
1624         pud_t *pud;
1625         pmd_t *pmd;
1626 
1627         if (pgd_none(*pgd)) {
1628                 pud_t *new;
1629 
1630                 new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1631                 if (!new)
1632                         goto err_alloc;
1633                 pgd_populate(&init_mm, pgd, new);
1634         }
1635 
1636         pud = pud_offset(pgd, addr);
1637         if (pud_none(*pud)) {
1638                 pmd_t *new;
1639 
1640                 new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1641                 if (!new)
1642                         goto err_alloc;
1643                 pud_populate(&init_mm, pud, new);
1644         }
1645 
1646         pmd = pmd_offset(pud, addr);
1647         if (!pmd_present(*pmd)) {
1648                 pte_t *new;
1649 
1650                 new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1651                 if (!new)
1652                         goto err_alloc;
1653                 pmd_populate_kernel(&init_mm, pmd, new);
1654         }
1655 
1656         return;
1657 
1658 err_alloc:
1659         panic("%s: Failed to allocate %lu bytes align=%lx from=%lx\n",
1660               __func__, PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
1661 }
1662 
1663 void __init setup_per_cpu_areas(void)
1664 {
1665         unsigned long delta;
1666         unsigned int cpu;
1667         int rc = -EINVAL;
1668 
1669         if (pcpu_chosen_fc != PCPU_FC_PAGE) {
1670                 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
1671                                             PERCPU_DYNAMIC_RESERVE, 4 << 20,
1672                                             pcpu_cpu_distance,
1673                                             pcpu_alloc_bootmem,
1674                                             pcpu_free_bootmem);
1675                 if (rc)
1676                         pr_warning("PERCPU: %s allocator failed (%d), "
1677                                    "falling back to page size\n",
1678                                    pcpu_fc_names[pcpu_chosen_fc], rc);
1679         }
1680         if (rc < 0)
1681                 rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
1682                                            pcpu_alloc_bootmem,
1683                                            pcpu_free_bootmem,
1684                                            pcpu_populate_pte);
1685         if (rc < 0)
1686                 panic("cannot initialize percpu area (err=%d)", rc);
1687 
1688         delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
1689         for_each_possible_cpu(cpu)
1690                 __per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];
1691 
1692         /* Setup %g5 for the boot cpu.  */
1693         __local_per_cpu_offset = __per_cpu_offset(smp_processor_id());
1694 
1695         of_fill_in_cpu_data();
1696         if (tlb_type == hypervisor)
1697                 mdesc_fill_in_cpu_data(cpu_all_mask);
1698 }
/* [<][>][^][v][top][bottom][index][help] */
root/arch/sparc/kernel/smp_64.c

DEFINITIONS
