1 /* 2 * arch/s390/kernel/smp.c 3 * 4 * Copyright IBM Corp. 1999, 2009 5 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), 6 * Martin Schwidefsky (schwidefsky@de.ibm.com) 7 * Heiko Carstens (heiko.carstens@de.ibm.com) 8 * 9 * based on other smp stuff by 10 * (c) 1995 Alan Cox, CymruNET Ltd <alan@cymru.net> 11 * (c) 1998 Ingo Molnar 12 * 13 * We work with logical cpu numbering everywhere we can. The only 14 * functions using the real cpu address (got from STAP) are the sigp 15 * functions. For all other functions we use the identity mapping. 16 * That means that cpu_number_map[i] == i for every cpu. cpu_number_map is 17 * used e.g. to find the idle task belonging to a logical cpu. Every array 18 * in the kernel is sorted by the logical cpu number and not by the physical 19 * one which is causing all the confusion with __cpu_logical_map and 20 * cpu_number_map in other architectures. 21 */ 22 23 #define KMSG_COMPONENT "cpu" 24 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 25 26 #include <linux/workqueue.h> 27 #include <linux/module.h> 28 #include <linux/init.h> 29 #include <linux/mm.h> 30 #include <linux/err.h> 31 #include <linux/spinlock.h> 32 #include <linux/kernel_stat.h> 33 #include <linux/delay.h> 34 #include <linux/cache.h> 35 #include <linux/interrupt.h> 36 #include <linux/irqflags.h> 37 #include <linux/cpu.h> 38 #include <linux/timex.h> 39 #include <linux/bootmem.h> 40 #include <linux/slab.h> 41 #include <asm/asm-offsets.h> 42 #include <asm/ipl.h> 43 #include <asm/setup.h> 44 #include <asm/sigp.h> 45 #include <asm/pgalloc.h> 46 #include <asm/irq.h> 47 #include <asm/s390_ext.h> 48 #include <asm/cpcmd.h> 49 #include <asm/tlbflush.h> 50 #include <asm/timer.h> 51 #include <asm/lowcore.h> 52 #include <asm/sclp.h> 53 #include <asm/cputime.h> 54 #include <asm/vdso.h> 55 #include <asm/cpu.h> 56 #include "entry.h" 57 58 /* logical cpu to cpu address */ 59 unsigned short __cpu_logical_map[NR_CPUS]; 60 61 static struct task_struct *current_set[NR_CPUS]; 62 63 static u8 smp_cpu_type; 64 static int smp_use_sigp_detection; 65 66 enum s390_cpu_state { 67 CPU_STATE_STANDBY, 68 CPU_STATE_CONFIGURED, 69 }; 70 71 DEFINE_MUTEX(smp_cpu_state_mutex); 72 int smp_cpu_polarization[NR_CPUS]; 73 static int smp_cpu_state[NR_CPUS]; 74 static int cpu_management; 75 76 static DEFINE_PER_CPU(struct cpu, cpu_devices); 77 78 static void smp_ext_bitcall(int, int); 79 80 static int raw_cpu_stopped(int cpu) 81 { 82 u32 status; 83 84 switch (raw_sigp_ps(&status, 0, cpu, sigp_sense)) { 85 case sigp_status_stored: 86 /* Check for stopped and check stop state */ 87 if (status & 0x50) 88 return 1; 89 break; 90 default: 91 break; 92 } 93 return 0; 94 } 95 96 static inline int cpu_stopped(int cpu) 97 { 98 return raw_cpu_stopped(cpu_logical_map(cpu)); 99 } 100 101 void smp_switch_to_ipl_cpu(void (*func)(void *), void *data) 102 { 103 struct _lowcore *lc, *current_lc; 104 struct stack_frame *sf; 105 struct pt_regs *regs; 106 unsigned long sp; 107 108 if (smp_processor_id() == 0) 109 func(data); 110 __load_psw_mask(PSW_BASE_BITS | PSW_DEFAULT_KEY); 111 /* Disable lowcore protection */ 112 __ctl_clear_bit(0, 28); 113 current_lc = lowcore_ptr[smp_processor_id()]; 114 lc = lowcore_ptr[0]; 115 if (!lc) 116 lc = current_lc; 117 lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY; 118 lc->restart_psw.addr = PSW_ADDR_AMODE | (unsigned long) smp_restart_cpu; 119 if (!cpu_online(0)) 120 smp_switch_to_cpu(func, data, 0, stap(), __cpu_logical_map[0]); 121 while (sigp(0, sigp_stop_and_store_status) == sigp_busy) 122 cpu_relax(); 123 sp = lc->panic_stack; 124 sp -= sizeof(struct pt_regs); 125 regs = (struct pt_regs *) sp; 126 memcpy(®s->gprs, ¤t_lc->gpregs_save_area, sizeof(regs->gprs)); 127 regs->psw = lc->psw_save_area; 128 sp -= STACK_FRAME_OVERHEAD; 129 sf = (struct stack_frame *) sp; 130 sf->back_chain = regs->gprs[15]; 131 smp_switch_to_cpu(func, data, sp, stap(), __cpu_logical_map[0]); 132 } 133 134 void smp_send_stop(void) 135 { 136 int cpu, rc; 137 138 /* Disable all interrupts/machine checks */ 139 __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK); 140 trace_hardirqs_off(); 141 142 /* stop all processors */ 143 for_each_online_cpu(cpu) { 144 if (cpu == smp_processor_id()) 145 continue; 146 do { 147 rc = sigp(cpu, sigp_stop); 148 } while (rc == sigp_busy); 149 150 while (!cpu_stopped(cpu)) 151 cpu_relax(); 152 } 153 } 154 155 /* 156 * This is the main routine where commands issued by other 157 * cpus are handled. 158 */ 159 160 static void do_ext_call_interrupt(unsigned int ext_int_code, 161 unsigned int param32, unsigned long param64) 162 { 163 unsigned long bits; 164 165 kstat_cpu(smp_processor_id()).irqs[EXTINT_IPI]++; 166 /* 167 * handle bit signal external calls 168 * 169 * For the ec_schedule signal we have to do nothing. All the work 170 * is done automatically when we return from the interrupt. 171 */ 172 bits = xchg(&S390_lowcore.ext_call_fast, 0); 173 174 if (test_bit(ec_call_function, &bits)) 175 generic_smp_call_function_interrupt(); 176 177 if (test_bit(ec_call_function_single, &bits)) 178 generic_smp_call_function_single_interrupt(); 179 } 180 181 /* 182 * Send an external call sigp to another cpu and return without waiting 183 * for its completion. 184 */ 185 static void smp_ext_bitcall(int cpu, int sig) 186 { 187 /* 188 * Set signaling bit in lowcore of target cpu and kick it 189 */ 190 set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast); 191 while (sigp(cpu, sigp_emergency_signal) == sigp_busy) 192 udelay(10); 193 } 194 195 void arch_send_call_function_ipi_mask(const struct cpumask *mask) 196 { 197 int cpu; 198 199 for_each_cpu(cpu, mask) 200 smp_ext_bitcall(cpu, ec_call_function); 201 } 202 203 void arch_send_call_function_single_ipi(int cpu) 204 { 205 smp_ext_bitcall(cpu, ec_call_function_single); 206 } 207 208 #ifndef CONFIG_64BIT 209 /* 210 * this function sends a 'purge tlb' signal to another CPU. 211 */ 212 static void smp_ptlb_callback(void *info) 213 { 214 __tlb_flush_local(); 215 } 216 217 void smp_ptlb_all(void) 218 { 219 on_each_cpu(smp_ptlb_callback, NULL, 1); 220 } 221 EXPORT_SYMBOL(smp_ptlb_all); 222 #endif /* ! CONFIG_64BIT */ 223 224 /* 225 * this function sends a 'reschedule' IPI to another CPU. 226 * it goes straight through and wastes no time serializing 227 * anything. Worst case is that we lose a reschedule ... 228 */ 229 void smp_send_reschedule(int cpu) 230 { 231 smp_ext_bitcall(cpu, ec_schedule); 232 } 233 234 /* 235 * parameter area for the set/clear control bit callbacks 236 */ 237 struct ec_creg_mask_parms { 238 unsigned long orvals[16]; 239 unsigned long andvals[16]; 240 }; 241 242 /* 243 * callback for setting/clearing control bits 244 */ 245 static void smp_ctl_bit_callback(void *info) 246 { 247 struct ec_creg_mask_parms *pp = info; 248 unsigned long cregs[16]; 249 int i; 250 251 __ctl_store(cregs, 0, 15); 252 for (i = 0; i <= 15; i++) 253 cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i]; 254 __ctl_load(cregs, 0, 15); 255 } 256 257 /* 258 * Set a bit in a control register of all cpus 259 */ 260 void smp_ctl_set_bit(int cr, int bit) 261 { 262 struct ec_creg_mask_parms parms; 263 264 memset(&parms.orvals, 0, sizeof(parms.orvals)); 265 memset(&parms.andvals, 0xff, sizeof(parms.andvals)); 266 parms.orvals[cr] = 1 << bit; 267 on_each_cpu(smp_ctl_bit_callback, &parms, 1); 268 } 269 EXPORT_SYMBOL(smp_ctl_set_bit); 270 271 /* 272 * Clear a bit in a control register of all cpus 273 */ 274 void smp_ctl_clear_bit(int cr, int bit) 275 { 276 struct ec_creg_mask_parms parms; 277 278 memset(&parms.orvals, 0, sizeof(parms.orvals)); 279 memset(&parms.andvals, 0xff, sizeof(parms.andvals)); 280 parms.andvals[cr] = ~(1L << bit); 281 on_each_cpu(smp_ctl_bit_callback, &parms, 1); 282 } 283 EXPORT_SYMBOL(smp_ctl_clear_bit); 284 285 #ifdef CONFIG_ZFCPDUMP 286 287 static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) 288 { 289 if (ipl_info.type != IPL_TYPE_FCP_DUMP) 290 return; 291 if (cpu >= NR_CPUS) { 292 pr_warning("CPU %i exceeds the maximum %i and is excluded from " 293 "the dump\n", cpu, NR_CPUS - 1); 294 return; 295 } 296 zfcpdump_save_areas[cpu] = kmalloc(sizeof(struct save_area), GFP_KERNEL); 297 while (raw_sigp(phy_cpu, sigp_stop_and_store_status) == sigp_busy) 298 cpu_relax(); 299 memcpy_real(zfcpdump_save_areas[cpu], 300 (void *)(unsigned long) store_prefix() + SAVE_AREA_BASE, 301 sizeof(struct save_area)); 302 } 303 304 struct save_area *zfcpdump_save_areas[NR_CPUS + 1]; 305 EXPORT_SYMBOL_GPL(zfcpdump_save_areas); 306 307 #else 308 309 static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { } 310 311 #endif /* CONFIG_ZFCPDUMP */ 312 313 static int cpu_known(int cpu_id) 314 { 315 int cpu; 316 317 for_each_present_cpu(cpu) { 318 if (__cpu_logical_map[cpu] == cpu_id) 319 return 1; 320 } 321 return 0; 322 } 323 324 static int smp_rescan_cpus_sigp(cpumask_t avail) 325 { 326 int cpu_id, logical_cpu; 327 328 logical_cpu = cpumask_first(&avail); 329 if (logical_cpu >= nr_cpu_ids) 330 return 0; 331 for (cpu_id = 0; cpu_id <= MAX_CPU_ADDRESS; cpu_id++) { 332 if (cpu_known(cpu_id)) 333 continue; 334 __cpu_logical_map[logical_cpu] = cpu_id; 335 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN; 336 if (!cpu_stopped(logical_cpu)) 337 continue; 338 cpu_set(logical_cpu, cpu_present_map); 339 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; 340 logical_cpu = cpumask_next(logical_cpu, &avail); 341 if (logical_cpu >= nr_cpu_ids) 342 break; 343 } 344 return 0; 345 } 346 347 static int smp_rescan_cpus_sclp(cpumask_t avail) 348 { 349 struct sclp_cpu_info *info; 350 int cpu_id, logical_cpu, cpu; 351 int rc; 352 353 logical_cpu = cpumask_first(&avail); 354 if (logical_cpu >= nr_cpu_ids) 355 return 0; 356 info = kmalloc(sizeof(*info), GFP_KERNEL); 357 if (!info) 358 return -ENOMEM; 359 rc = sclp_get_cpu_info(info); 360 if (rc) 361 goto out; 362 for (cpu = 0; cpu < info->combined; cpu++) { 363 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) 364 continue; 365 cpu_id = info->cpu[cpu].address; 366 if (cpu_known(cpu_id)) 367 continue; 368 __cpu_logical_map[logical_cpu] = cpu_id; 369 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN; 370 cpu_set(logical_cpu, cpu_present_map); 371 if (cpu >= info->configured) 372 smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY; 373 else 374 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; 375 logical_cpu = cpumask_next(logical_cpu, &avail); 376 if (logical_cpu >= nr_cpu_ids) 377 break; 378 } 379 out: 380 kfree(info); 381 return rc; 382 } 383 384 static int __smp_rescan_cpus(void) 385 { 386 cpumask_t avail; 387 388 cpus_xor(avail, cpu_possible_map, cpu_present_map); 389 if (smp_use_sigp_detection) 390 return smp_rescan_cpus_sigp(avail); 391 else 392 return smp_rescan_cpus_sclp(avail); 393 } 394 395 static void __init smp_detect_cpus(void) 396 { 397 unsigned int cpu, c_cpus, s_cpus; 398 struct sclp_cpu_info *info; 399 u16 boot_cpu_addr, cpu_addr; 400 401 c_cpus = 1; 402 s_cpus = 0; 403 boot_cpu_addr = __cpu_logical_map[0]; 404 info = kmalloc(sizeof(*info), GFP_KERNEL); 405 if (!info) 406 panic("smp_detect_cpus failed to allocate memory\n"); 407 /* Use sigp detection algorithm if sclp doesn't work. */ 408 if (sclp_get_cpu_info(info)) { 409 smp_use_sigp_detection = 1; 410 for (cpu = 0; cpu <= MAX_CPU_ADDRESS; cpu++) { 411 if (cpu == boot_cpu_addr) 412 continue; 413 if (!raw_cpu_stopped(cpu)) 414 continue; 415 smp_get_save_area(c_cpus, cpu); 416 c_cpus++; 417 } 418 goto out; 419 } 420 421 if (info->has_cpu_type) { 422 for (cpu = 0; cpu < info->combined; cpu++) { 423 if (info->cpu[cpu].address == boot_cpu_addr) { 424 smp_cpu_type = info->cpu[cpu].type; 425 break; 426 } 427 } 428 } 429 430 for (cpu = 0; cpu < info->combined; cpu++) { 431 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) 432 continue; 433 cpu_addr = info->cpu[cpu].address; 434 if (cpu_addr == boot_cpu_addr) 435 continue; 436 if (!raw_cpu_stopped(cpu_addr)) { 437 s_cpus++; 438 continue; 439 } 440 smp_get_save_area(c_cpus, cpu_addr); 441 c_cpus++; 442 } 443 out: 444 kfree(info); 445 pr_info("%d configured CPUs, %d standby CPUs\n", c_cpus, s_cpus); 446 get_online_cpus(); 447 __smp_rescan_cpus(); 448 put_online_cpus(); 449 } 450 451 /* 452 * Activate a secondary processor. 453 */ 454 int __cpuinit start_secondary(void *cpuvoid) 455 { 456 /* Setup the cpu */ 457 cpu_init(); 458 preempt_disable(); 459 /* Enable TOD clock interrupts on the secondary cpu. */ 460 init_cpu_timer(); 461 /* Enable cpu timer interrupts on the secondary cpu. */ 462 init_cpu_vtimer(); 463 /* Enable pfault pseudo page faults on this cpu. */ 464 pfault_init(); 465 466 /* call cpu notifiers */ 467 notify_cpu_starting(smp_processor_id()); 468 /* Mark this cpu as online */ 469 ipi_call_lock(); 470 cpu_set(smp_processor_id(), cpu_online_map); 471 ipi_call_unlock(); 472 /* Switch on interrupts */ 473 local_irq_enable(); 474 /* cpu_idle will call schedule for us */ 475 cpu_idle(); 476 return 0; 477 } 478 479 struct create_idle { 480 struct work_struct work; 481 struct task_struct *idle; 482 struct completion done; 483 int cpu; 484 }; 485 486 static void __cpuinit smp_fork_idle(struct work_struct *work) 487 { 488 struct create_idle *c_idle; 489 490 c_idle = container_of(work, struct create_idle, work); 491 c_idle->idle = fork_idle(c_idle->cpu); 492 complete(&c_idle->done); 493 } 494 495 static int __cpuinit smp_alloc_lowcore(int cpu) 496 { 497 unsigned long async_stack, panic_stack; 498 struct _lowcore *lowcore; 499 500 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, LC_ORDER); 501 if (!lowcore) 502 return -ENOMEM; 503 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); 504 panic_stack = __get_free_page(GFP_KERNEL); 505 if (!panic_stack || !async_stack) 506 goto out; 507 memcpy(lowcore, &S390_lowcore, 512); 508 memset((char *)lowcore + 512, 0, sizeof(*lowcore) - 512); 509 lowcore->async_stack = async_stack + ASYNC_SIZE; 510 lowcore->panic_stack = panic_stack + PAGE_SIZE; 511 512 #ifndef CONFIG_64BIT 513 if (MACHINE_HAS_IEEE) { 514 unsigned long save_area; 515 516 save_area = get_zeroed_page(GFP_KERNEL); 517 if (!save_area) 518 goto out; 519 lowcore->extended_save_area_addr = (u32) save_area; 520 } 521 #else 522 if (vdso_alloc_per_cpu(cpu, lowcore)) 523 goto out; 524 #endif 525 lowcore_ptr[cpu] = lowcore; 526 return 0; 527 528 out: 529 free_page(panic_stack); 530 free_pages(async_stack, ASYNC_ORDER); 531 free_pages((unsigned long) lowcore, LC_ORDER); 532 return -ENOMEM; 533 } 534 535 static void smp_free_lowcore(int cpu) 536 { 537 struct _lowcore *lowcore; 538 539 lowcore = lowcore_ptr[cpu]; 540 #ifndef CONFIG_64BIT 541 if (MACHINE_HAS_IEEE) 542 free_page((unsigned long) lowcore->extended_save_area_addr); 543 #else 544 vdso_free_per_cpu(cpu, lowcore); 545 #endif 546 free_page(lowcore->panic_stack - PAGE_SIZE); 547 free_pages(lowcore->async_stack - ASYNC_SIZE, ASYNC_ORDER); 548 free_pages((unsigned long) lowcore, LC_ORDER); 549 lowcore_ptr[cpu] = NULL; 550 } 551 552 /* Upping and downing of CPUs */ 553 int __cpuinit __cpu_up(unsigned int cpu) 554 { 555 struct _lowcore *cpu_lowcore; 556 struct create_idle c_idle; 557 struct task_struct *idle; 558 struct stack_frame *sf; 559 u32 lowcore; 560 int ccode; 561 562 if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED) 563 return -EIO; 564 idle = current_set[cpu]; 565 if (!idle) { 566 c_idle.done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done); 567 INIT_WORK_ONSTACK(&c_idle.work, smp_fork_idle); 568 c_idle.cpu = cpu; 569 schedule_work(&c_idle.work); 570 wait_for_completion(&c_idle.done); 571 if (IS_ERR(c_idle.idle)) 572 return PTR_ERR(c_idle.idle); 573 idle = c_idle.idle; 574 current_set[cpu] = c_idle.idle; 575 } 576 init_idle(idle, cpu); 577 if (smp_alloc_lowcore(cpu)) 578 return -ENOMEM; 579 do { 580 ccode = sigp(cpu, sigp_initial_cpu_reset); 581 if (ccode == sigp_busy) 582 udelay(10); 583 if (ccode == sigp_not_operational) 584 goto err_out; 585 } while (ccode == sigp_busy); 586 587 lowcore = (u32)(unsigned long)lowcore_ptr[cpu]; 588 while (sigp_p(lowcore, cpu, sigp_set_prefix) == sigp_busy) 589 udelay(10); 590 591 cpu_lowcore = lowcore_ptr[cpu]; 592 cpu_lowcore->kernel_stack = (unsigned long) 593 task_stack_page(idle) + THREAD_SIZE; 594 cpu_lowcore->thread_info = (unsigned long) task_thread_info(idle); 595 sf = (struct stack_frame *) (cpu_lowcore->kernel_stack 596 - sizeof(struct pt_regs) 597 - sizeof(struct stack_frame)); 598 memset(sf, 0, sizeof(struct stack_frame)); 599 sf->gprs[9] = (unsigned long) sf; 600 cpu_lowcore->save_area[15] = (unsigned long) sf; 601 __ctl_store(cpu_lowcore->cregs_save_area, 0, 15); 602 atomic_inc(&init_mm.context.attach_count); 603 asm volatile( 604 " stam 0,15,0(%0)" 605 : : "a" (&cpu_lowcore->access_regs_save_area) : "memory"); 606 cpu_lowcore->percpu_offset = __per_cpu_offset[cpu]; 607 cpu_lowcore->current_task = (unsigned long) idle; 608 cpu_lowcore->cpu_nr = cpu; 609 cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce; 610 cpu_lowcore->machine_flags = S390_lowcore.machine_flags; 611 cpu_lowcore->ftrace_func = S390_lowcore.ftrace_func; 612 memcpy(cpu_lowcore->stfle_fac_list, S390_lowcore.stfle_fac_list, 613 MAX_FACILITY_BIT/8); 614 eieio(); 615 616 while (sigp(cpu, sigp_restart) == sigp_busy) 617 udelay(10); 618 619 while (!cpu_online(cpu)) 620 cpu_relax(); 621 return 0; 622 623 err_out: 624 smp_free_lowcore(cpu); 625 return -EIO; 626 } 627 628 static int __init setup_possible_cpus(char *s) 629 { 630 int pcpus, cpu; 631 632 pcpus = simple_strtoul(s, NULL, 0); 633 init_cpu_possible(cpumask_of(0)); 634 for (cpu = 1; cpu < pcpus && cpu < nr_cpu_ids; cpu++) 635 set_cpu_possible(cpu, true); 636 return 0; 637 } 638 early_param("possible_cpus", setup_possible_cpus); 639 640 #ifdef CONFIG_HOTPLUG_CPU 641 642 int __cpu_disable(void) 643 { 644 struct ec_creg_mask_parms cr_parms; 645 int cpu = smp_processor_id(); 646 647 cpu_clear(cpu, cpu_online_map); 648 649 /* Disable pfault pseudo page faults on this cpu. */ 650 pfault_fini(); 651 652 memset(&cr_parms.orvals, 0, sizeof(cr_parms.orvals)); 653 memset(&cr_parms.andvals, 0xff, sizeof(cr_parms.andvals)); 654 655 /* disable all external interrupts */ 656 cr_parms.orvals[0] = 0; 657 cr_parms.andvals[0] = ~(1 << 15 | 1 << 14 | 1 << 13 | 1 << 12 | 658 1 << 11 | 1 << 10 | 1 << 6 | 1 << 4); 659 /* disable all I/O interrupts */ 660 cr_parms.orvals[6] = 0; 661 cr_parms.andvals[6] = ~(1 << 31 | 1 << 30 | 1 << 29 | 1 << 28 | 662 1 << 27 | 1 << 26 | 1 << 25 | 1 << 24); 663 /* disable most machine checks */ 664 cr_parms.orvals[14] = 0; 665 cr_parms.andvals[14] = ~(1 << 28 | 1 << 27 | 1 << 26 | 666 1 << 25 | 1 << 24); 667 668 smp_ctl_bit_callback(&cr_parms); 669 670 return 0; 671 } 672 673 void __cpu_die(unsigned int cpu) 674 { 675 /* Wait until target cpu is down */ 676 while (!cpu_stopped(cpu)) 677 cpu_relax(); 678 while (sigp_p(0, cpu, sigp_set_prefix) == sigp_busy) 679 udelay(10); 680 smp_free_lowcore(cpu); 681 atomic_dec(&init_mm.context.attach_count); 682 } 683 684 void cpu_die(void) 685 { 686 idle_task_exit(); 687 while (sigp(smp_processor_id(), sigp_stop) == sigp_busy) 688 cpu_relax(); 689 for (;;); 690 } 691 692 #endif /* CONFIG_HOTPLUG_CPU */ 693 694 void __init smp_prepare_cpus(unsigned int max_cpus) 695 { 696 #ifndef CONFIG_64BIT 697 unsigned long save_area = 0; 698 #endif 699 unsigned long async_stack, panic_stack; 700 struct _lowcore *lowcore; 701 702 smp_detect_cpus(); 703 704 /* request the 0x1201 emergency signal external interrupt */ 705 if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0) 706 panic("Couldn't request external interrupt 0x1201"); 707 708 /* Reallocate current lowcore, but keep its contents. */ 709 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, LC_ORDER); 710 panic_stack = __get_free_page(GFP_KERNEL); 711 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); 712 BUG_ON(!lowcore || !panic_stack || !async_stack); 713 #ifndef CONFIG_64BIT 714 if (MACHINE_HAS_IEEE) 715 save_area = get_zeroed_page(GFP_KERNEL); 716 #endif 717 local_irq_disable(); 718 local_mcck_disable(); 719 lowcore_ptr[smp_processor_id()] = lowcore; 720 *lowcore = S390_lowcore; 721 lowcore->panic_stack = panic_stack + PAGE_SIZE; 722 lowcore->async_stack = async_stack + ASYNC_SIZE; 723 #ifndef CONFIG_64BIT 724 if (MACHINE_HAS_IEEE) 725 lowcore->extended_save_area_addr = (u32) save_area; 726 #endif 727 set_prefix((u32)(unsigned long) lowcore); 728 local_mcck_enable(); 729 local_irq_enable(); 730 #ifdef CONFIG_64BIT 731 if (vdso_alloc_per_cpu(smp_processor_id(), &S390_lowcore)) 732 BUG(); 733 #endif 734 } 735 736 void __init smp_prepare_boot_cpu(void) 737 { 738 BUG_ON(smp_processor_id() != 0); 739 740 current_thread_info()->cpu = 0; 741 cpu_set(0, cpu_present_map); 742 cpu_set(0, cpu_online_map); 743 S390_lowcore.percpu_offset = __per_cpu_offset[0]; 744 current_set[0] = current; 745 smp_cpu_state[0] = CPU_STATE_CONFIGURED; 746 smp_cpu_polarization[0] = POLARIZATION_UNKNWN; 747 } 748 749 void __init smp_cpus_done(unsigned int max_cpus) 750 { 751 } 752 753 void __init smp_setup_processor_id(void) 754 { 755 S390_lowcore.cpu_nr = 0; 756 __cpu_logical_map[0] = stap(); 757 } 758 759 /* 760 * the frequency of the profiling timer can be changed 761 * by writing a multiplier value into /proc/profile. 762 * 763 * usually you want to run this on all CPUs ;) 764 */ 765 int setup_profiling_timer(unsigned int multiplier) 766 { 767 return 0; 768 } 769 770 #ifdef CONFIG_HOTPLUG_CPU 771 static ssize_t cpu_configure_show(struct sys_device *dev, 772 struct sysdev_attribute *attr, char *buf) 773 { 774 ssize_t count; 775 776 mutex_lock(&smp_cpu_state_mutex); 777 count = sprintf(buf, "%d\n", smp_cpu_state[dev->id]); 778 mutex_unlock(&smp_cpu_state_mutex); 779 return count; 780 } 781 782 static ssize_t cpu_configure_store(struct sys_device *dev, 783 struct sysdev_attribute *attr, 784 const char *buf, size_t count) 785 { 786 int cpu = dev->id; 787 int val, rc; 788 char delim; 789 790 if (sscanf(buf, "%d %c", &val, &delim) != 1) 791 return -EINVAL; 792 if (val != 0 && val != 1) 793 return -EINVAL; 794 795 get_online_cpus(); 796 mutex_lock(&smp_cpu_state_mutex); 797 rc = -EBUSY; 798 /* disallow configuration changes of online cpus and cpu 0 */ 799 if (cpu_online(cpu) || cpu == 0) 800 goto out; 801 rc = 0; 802 switch (val) { 803 case 0: 804 if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) { 805 rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]); 806 if (!rc) { 807 smp_cpu_state[cpu] = CPU_STATE_STANDBY; 808 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN; 809 } 810 } 811 break; 812 case 1: 813 if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) { 814 rc = sclp_cpu_configure(__cpu_logical_map[cpu]); 815 if (!rc) { 816 smp_cpu_state[cpu] = CPU_STATE_CONFIGURED; 817 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN; 818 } 819 } 820 break; 821 default: 822 break; 823 } 824 out: 825 mutex_unlock(&smp_cpu_state_mutex); 826 put_online_cpus(); 827 return rc ? rc : count; 828 } 829 static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store); 830 #endif /* CONFIG_HOTPLUG_CPU */ 831 832 static ssize_t cpu_polarization_show(struct sys_device *dev, 833 struct sysdev_attribute *attr, char *buf) 834 { 835 int cpu = dev->id; 836 ssize_t count; 837 838 mutex_lock(&smp_cpu_state_mutex); 839 switch (smp_cpu_polarization[cpu]) { 840 case POLARIZATION_HRZ: 841 count = sprintf(buf, "horizontal\n"); 842 break; 843 case POLARIZATION_VL: 844 count = sprintf(buf, "vertical:low\n"); 845 break; 846 case POLARIZATION_VM: 847 count = sprintf(buf, "vertical:medium\n"); 848 break; 849 case POLARIZATION_VH: 850 count = sprintf(buf, "vertical:high\n"); 851 break; 852 default: 853 count = sprintf(buf, "unknown\n"); 854 break; 855 } 856 mutex_unlock(&smp_cpu_state_mutex); 857 return count; 858 } 859 static SYSDEV_ATTR(polarization, 0444, cpu_polarization_show, NULL); 860 861 static ssize_t show_cpu_address(struct sys_device *dev, 862 struct sysdev_attribute *attr, char *buf) 863 { 864 return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]); 865 } 866 static SYSDEV_ATTR(address, 0444, show_cpu_address, NULL); 867 868 869 static struct attribute *cpu_common_attrs[] = { 870 #ifdef CONFIG_HOTPLUG_CPU 871 &attr_configure.attr, 872 #endif 873 &attr_address.attr, 874 &attr_polarization.attr, 875 NULL, 876 }; 877 878 static struct attribute_group cpu_common_attr_group = { 879 .attrs = cpu_common_attrs, 880 }; 881 882 static ssize_t show_capability(struct sys_device *dev, 883 struct sysdev_attribute *attr, char *buf) 884 { 885 unsigned int capability; 886 int rc; 887 888 rc = get_cpu_capability(&capability); 889 if (rc) 890 return rc; 891 return sprintf(buf, "%u\n", capability); 892 } 893 static SYSDEV_ATTR(capability, 0444, show_capability, NULL); 894 895 static ssize_t show_idle_count(struct sys_device *dev, 896 struct sysdev_attribute *attr, char *buf) 897 { 898 struct s390_idle_data *idle; 899 unsigned long long idle_count; 900 unsigned int sequence; 901 902 idle = &per_cpu(s390_idle, dev->id); 903 repeat: 904 sequence = idle->sequence; 905 smp_rmb(); 906 if (sequence & 1) 907 goto repeat; 908 idle_count = idle->idle_count; 909 if (idle->idle_enter) 910 idle_count++; 911 smp_rmb(); 912 if (idle->sequence != sequence) 913 goto repeat; 914 return sprintf(buf, "%llu\n", idle_count); 915 } 916 static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL); 917 918 static ssize_t show_idle_time(struct sys_device *dev, 919 struct sysdev_attribute *attr, char *buf) 920 { 921 struct s390_idle_data *idle; 922 unsigned long long now, idle_time, idle_enter; 923 unsigned int sequence; 924 925 idle = &per_cpu(s390_idle, dev->id); 926 now = get_clock(); 927 repeat: 928 sequence = idle->sequence; 929 smp_rmb(); 930 if (sequence & 1) 931 goto repeat; 932 idle_time = idle->idle_time; 933 idle_enter = idle->idle_enter; 934 if (idle_enter != 0ULL && idle_enter < now) 935 idle_time += now - idle_enter; 936 smp_rmb(); 937 if (idle->sequence != sequence) 938 goto repeat; 939 return sprintf(buf, "%llu\n", idle_time >> 12); 940 } 941 static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL); 942 943 static struct attribute *cpu_online_attrs[] = { 944 &attr_capability.attr, 945 &attr_idle_count.attr, 946 &attr_idle_time_us.attr, 947 NULL, 948 }; 949 950 static struct attribute_group cpu_online_attr_group = { 951 .attrs = cpu_online_attrs, 952 }; 953 954 static int __cpuinit smp_cpu_notify(struct notifier_block *self, 955 unsigned long action, void *hcpu) 956 { 957 unsigned int cpu = (unsigned int)(long)hcpu; 958 struct cpu *c = &per_cpu(cpu_devices, cpu); 959 struct sys_device *s = &c->sysdev; 960 struct s390_idle_data *idle; 961 int err = 0; 962 963 switch (action) { 964 case CPU_ONLINE: 965 case CPU_ONLINE_FROZEN: 966 idle = &per_cpu(s390_idle, cpu); 967 memset(idle, 0, sizeof(struct s390_idle_data)); 968 err = sysfs_create_group(&s->kobj, &cpu_online_attr_group); 969 break; 970 case CPU_DEAD: 971 case CPU_DEAD_FROZEN: 972 sysfs_remove_group(&s->kobj, &cpu_online_attr_group); 973 break; 974 } 975 return notifier_from_errno(err); 976 } 977 978 static struct notifier_block __cpuinitdata smp_cpu_nb = { 979 .notifier_call = smp_cpu_notify, 980 }; 981 982 static int __devinit smp_add_present_cpu(int cpu) 983 { 984 struct cpu *c = &per_cpu(cpu_devices, cpu); 985 struct sys_device *s = &c->sysdev; 986 int rc; 987 988 c->hotpluggable = 1; 989 rc = register_cpu(c, cpu); 990 if (rc) 991 goto out; 992 rc = sysfs_create_group(&s->kobj, &cpu_common_attr_group); 993 if (rc) 994 goto out_cpu; 995 if (!cpu_online(cpu)) 996 goto out; 997 rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group); 998 if (!rc) 999 return 0; 1000 sysfs_remove_group(&s->kobj, &cpu_common_attr_group); 1001 out_cpu: 1002 #ifdef CONFIG_HOTPLUG_CPU 1003 unregister_cpu(c); 1004 #endif 1005 out: 1006 return rc; 1007 } 1008 1009 #ifdef CONFIG_HOTPLUG_CPU 1010 1011 int __ref smp_rescan_cpus(void) 1012 { 1013 cpumask_t newcpus; 1014 int cpu; 1015 int rc; 1016 1017 get_online_cpus(); 1018 mutex_lock(&smp_cpu_state_mutex); 1019 newcpus = cpu_present_map; 1020 rc = __smp_rescan_cpus(); 1021 if (rc) 1022 goto out; 1023 cpus_andnot(newcpus, cpu_present_map, newcpus); 1024 for_each_cpu_mask(cpu, newcpus) { 1025 rc = smp_add_present_cpu(cpu); 1026 if (rc) 1027 cpu_clear(cpu, cpu_present_map); 1028 } 1029 rc = 0; 1030 out: 1031 mutex_unlock(&smp_cpu_state_mutex); 1032 put_online_cpus(); 1033 if (!cpus_empty(newcpus)) 1034 topology_schedule_update(); 1035 return rc; 1036 } 1037 1038 static ssize_t __ref rescan_store(struct sysdev_class *class, 1039 struct sysdev_class_attribute *attr, 1040 const char *buf, 1041 size_t count) 1042 { 1043 int rc; 1044 1045 rc = smp_rescan_cpus(); 1046 return rc ? rc : count; 1047 } 1048 static SYSDEV_CLASS_ATTR(rescan, 0200, NULL, rescan_store); 1049 #endif /* CONFIG_HOTPLUG_CPU */ 1050 1051 static ssize_t dispatching_show(struct sysdev_class *class, 1052 struct sysdev_class_attribute *attr, 1053 char *buf) 1054 { 1055 ssize_t count; 1056 1057 mutex_lock(&smp_cpu_state_mutex); 1058 count = sprintf(buf, "%d\n", cpu_management); 1059 mutex_unlock(&smp_cpu_state_mutex); 1060 return count; 1061 } 1062 1063 static ssize_t dispatching_store(struct sysdev_class *dev, 1064 struct sysdev_class_attribute *attr, 1065 const char *buf, 1066 size_t count) 1067 { 1068 int val, rc; 1069 char delim; 1070 1071 if (sscanf(buf, "%d %c", &val, &delim) != 1) 1072 return -EINVAL; 1073 if (val != 0 && val != 1) 1074 return -EINVAL; 1075 rc = 0; 1076 get_online_cpus(); 1077 mutex_lock(&smp_cpu_state_mutex); 1078 if (cpu_management == val) 1079 goto out; 1080 rc = topology_set_cpu_management(val); 1081 if (!rc) 1082 cpu_management = val; 1083 out: 1084 mutex_unlock(&smp_cpu_state_mutex); 1085 put_online_cpus(); 1086 return rc ? rc : count; 1087 } 1088 static SYSDEV_CLASS_ATTR(dispatching, 0644, dispatching_show, 1089 dispatching_store); 1090 1091 static int __init topology_init(void) 1092 { 1093 int cpu; 1094 int rc; 1095 1096 register_cpu_notifier(&smp_cpu_nb); 1097 1098 #ifdef CONFIG_HOTPLUG_CPU 1099 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_rescan); 1100 if (rc) 1101 return rc; 1102 #endif 1103 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_dispatching); 1104 if (rc) 1105 return rc; 1106 for_each_present_cpu(cpu) { 1107 rc = smp_add_present_cpu(cpu); 1108 if (rc) 1109 return rc; 1110 } 1111 return 0; 1112 } 1113 subsys_initcall(topology_init); 1114