arch/mips/cavium-octeon/smp.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2004-2008, 2009, 2010 Cavium Networks
   7  */
   8 #include <linux/cpu.h>
   9 #include <linux/delay.h>
  10 #include <linux/smp.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/kernel_stat.h>
  13 #include <linux/sched.h>
  14 #include <linux/module.h>
  15
  16 #include <asm/mmu_context.h>
  17 #include <asm/time.h>
  18 #include <asm/setup.h>
  19
  20 #include <asm/octeon/octeon.h>
  21
  22 #include "octeon_boot.h"
  23
  24 volatile unsigned long octeon_processor_boot = 0xff;
  25 volatile unsigned long octeon_processor_sp;
  26 volatile unsigned long octeon_processor_gp;
  27
  28 #ifdef CONFIG_HOTPLUG_CPU
  29 uint64_t octeon_bootloader_entry_addr;
  30 EXPORT_SYMBOL(octeon_bootloader_entry_addr);
  31 #endif
  32
  33 static void octeon_icache_flush(void)
  34 {
  35         asm volatile ("synci 0($0)\n");
  36 }
  37
  38 static void (*octeon_message_functions[8])(void) = {
  39         scheduler_ipi,
  40         generic_smp_call_function_interrupt,
  41         octeon_icache_flush,
  42 };
  43
  44 static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
  45 {
  46         u64 mbox_clrx = CVMX_CIU_MBOX_CLRX(cvmx_get_core_num());
  47         u64 action;
  48         int i;
  49
  50         /*
  51          * Make sure the function array initialization remains
  52          * correct.
  53          */
  54         BUILD_BUG_ON(SMP_RESCHEDULE_YOURSELF != (1 << 0));
  55         BUILD_BUG_ON(SMP_CALL_FUNCTION       != (1 << 1));
  56         BUILD_BUG_ON(SMP_ICACHE_FLUSH        != (1 << 2));
  57
  58         /*
  59          * Load the mailbox register to figure out what we're supposed
  60          * to do.
  61          */
  62         action = cvmx_read_csr(mbox_clrx);
  63
  64         if (OCTEON_IS_MODEL(OCTEON_CN68XX))
  65                 action &= 0xff;
  66         else
  67                 action &= 0xffff;
  68
  69         /* Clear the mailbox to clear the interrupt */
  70         cvmx_write_csr(mbox_clrx, action);
  71
  72         for (i = 0; i < ARRAY_SIZE(octeon_message_functions) && action;) {
  73                 if (action & 1) {
  74                         void (*fn)(void) = octeon_message_functions[i];
  75
  76                         if (fn)
  77                                 fn();
  78                 }
  79                 action >>= 1;
  80                 i++;
  81         }
  82         return IRQ_HANDLED;
  83 }
  84
  85 /**
  86  * Cause the function described by call_data to be executed on the passed
  87  * cpu.  When the function has finished, increment the finished field of
  88  * call_data.
  89  */
  90 void octeon_send_ipi_single(int cpu, unsigned int action)
  91 {
  92         int coreid = cpu_logical_map(cpu);
  93         /*
  94         pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
  95                coreid, action);
  96         */
  97         cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
  98 }
  99
 100 static inline void octeon_send_ipi_mask(const struct cpumask *mask,
 101                                         unsigned int action)
 102 {
 103         unsigned int i;
 104
 105         for_each_cpu(i, mask)
 106                 octeon_send_ipi_single(i, action);
 107 }
 108
 109 /**
 110  * Detect available CPUs, populate cpu_possible_mask
 111  */
 112 static void octeon_smp_hotplug_setup(void)
 113 {
 114 #ifdef CONFIG_HOTPLUG_CPU
 115         struct linux_app_boot_info *labi;
 116
 117         if (!setup_max_cpus)
 118                 return;
 119
 120         labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 121         if (labi->labi_signature != LABI_SIGNATURE) {
 122                 pr_info("The bootloader on this board does not support HOTPLUG_CPU.");
 123                 return;
 124         }
 125
 126         octeon_bootloader_entry_addr = labi->InitTLBStart_addr;
 127 #endif
 128 }
 129
 130 static void __init octeon_smp_setup(void)
 131 {
 132         const int coreid = cvmx_get_core_num();
 133         int cpus;
 134         int id;
 135         struct cvmx_sysinfo *sysinfo = cvmx_sysinfo_get();
 136
 137 #ifdef CONFIG_HOTPLUG_CPU
 138         int core_mask = octeon_get_boot_coremask();
 139         unsigned int num_cores = cvmx_octeon_num_cores();
 140 #endif
 141
 142         /* The present CPUs are initially just the boot cpu (CPU 0). */
 143         for (id = 0; id < NR_CPUS; id++) {
 144                 set_cpu_possible(id, id == 0);
 145                 set_cpu_present(id, id == 0);
 146         }
 147
 148         __cpu_number_map[coreid] = 0;
 149         __cpu_logical_map[0] = coreid;
 150
 151         /* The present CPUs get the lowest CPU numbers. */
 152         cpus = 1;
 153         for (id = 0; id < NR_CPUS; id++) {
 154                 if ((id != coreid) && cvmx_coremask_is_core_set(&sysinfo->core_mask, id)) {
 155                         set_cpu_possible(cpus, true);
 156                         set_cpu_present(cpus, true);
 157                         __cpu_number_map[id] = cpus;
 158                         __cpu_logical_map[cpus] = id;
 159                         cpus++;
 160                 }
 161         }
 162
 163 #ifdef CONFIG_HOTPLUG_CPU
 164         /*
 165          * The possible CPUs are all those present on the chip.  We
 166          * will assign CPU numbers for possible cores as well.  Cores
 167          * are always consecutively numberd from 0.
 168          */
 169         for (id = 0; setup_max_cpus && octeon_bootloader_entry_addr &&
 170                      id < num_cores && id < NR_CPUS; id++) {
 171                 if (!(core_mask & (1 << id))) {
 172                         set_cpu_possible(cpus, true);
 173                         __cpu_number_map[id] = cpus;
 174                         __cpu_logical_map[cpus] = id;
 175                         cpus++;
 176                 }
 177         }
 178 #endif
 179
 180         octeon_smp_hotplug_setup();
 181 }
 182
 183 /**
 184  * Firmware CPU startup hook
 185  *
 186  */
 187 static void octeon_boot_secondary(int cpu, struct task_struct *idle)
 188 {
 189         int count;
 190
 191         pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
 192                 cpu_logical_map(cpu));
 193
 194         octeon_processor_sp = __KSTK_TOS(idle);
 195         octeon_processor_gp = (unsigned long)(task_thread_info(idle));
 196         octeon_processor_boot = cpu_logical_map(cpu);
 197         mb();
 198
 199         count = 10000;
 200         while (octeon_processor_sp && count) {
 201                 /* Waiting for processor to get the SP and GP */
 202                 udelay(1);
 203                 count--;
 204         }
 205         if (count == 0)
 206                 pr_err("Secondary boot timeout\n");
 207 }
 208
 209 /**
 210  * After we've done initial boot, this function is called to allow the
 211  * board code to clean up state, if needed
 212  */
 213 static void octeon_init_secondary(void)
 214 {
 215         unsigned int sr;
 216
 217         sr = set_c0_status(ST0_BEV);
 218         write_c0_ebase((u32)ebase);
 219         write_c0_status(sr);
 220
 221         octeon_check_cpu_bist();
 222         octeon_init_cvmcount();
 223
 224         octeon_irq_setup_secondary();
 225 }
 226
 227 /**
 228  * Callout to firmware before smp_init
 229  *
 230  */
 231 static void __init octeon_prepare_cpus(unsigned int max_cpus)
 232 {
 233         /*
 234          * Only the low order mailbox bits are used for IPIs, leave
 235          * the other bits alone.
 236          */
 237         cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffff);
 238         if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt,
 239                         IRQF_PERCPU | IRQF_NO_THREAD, "SMP-IPI",
 240                         mailbox_interrupt)) {
 241                 panic("Cannot request_irq(OCTEON_IRQ_MBOX0)");
 242         }
 243 }
 244
 245 /**
 246  * Last chance for the board code to finish SMP initialization before
 247  * the CPU is "online".
 248  */
 249 static void octeon_smp_finish(void)
 250 {
 251         octeon_user_io_init();
 252
 253         /* to generate the first CPU timer interrupt */
 254         write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
 255         local_irq_enable();
 256 }
 257
 258 #ifdef CONFIG_HOTPLUG_CPU
 259
 260 /* State of each CPU. */
 261 DEFINE_PER_CPU(int, cpu_state);
 262
 263 static int octeon_cpu_disable(void)
 264 {
 265         unsigned int cpu = smp_processor_id();
 266
 267         if (cpu == 0)
 268                 return -EBUSY;
 269
 270         if (!octeon_bootloader_entry_addr)
 271                 return -ENOTSUPP;
 272
 273         set_cpu_online(cpu, false);
 274         cpumask_clear_cpu(cpu, &cpu_callin_map);
 275         octeon_fixup_irqs();
 276
 277         __flush_cache_all();
 278         local_flush_tlb_all();
 279
 280         return 0;
 281 }
 282
 283 static void octeon_cpu_die(unsigned int cpu)
 284 {
 285         int coreid = cpu_logical_map(cpu);
 286         uint32_t mask, new_mask;
 287         const struct cvmx_bootmem_named_block_desc *block_desc;
 288
 289         while (per_cpu(cpu_state, cpu) != CPU_DEAD)
 290                 cpu_relax();
 291
 292         /*
 293          * This is a bit complicated strategics of getting/settig available
 294          * cores mask, copied from bootloader
 295          */
 296
 297         mask = 1 << coreid;
 298         /* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
 299         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 300
 301         if (!block_desc) {
 302                 struct linux_app_boot_info *labi;
 303
 304                 labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 305
 306                 labi->avail_coremask |= mask;
 307                 new_mask = labi->avail_coremask;
 308         } else {                       /* alternative, already initialized */
 309                 uint32_t *p = (uint32_t *)PHYS_TO_XKSEG_CACHED(block_desc->base_addr +
 310                                                                AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
 311                 *p |= mask;
 312                 new_mask = *p;
 313         }
 314
 315         pr_info("Reset core %d. Available Coremask = 0x%x \n", coreid, new_mask);
 316         mb();
 317         cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 318         cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 319 }
 320
 321 void play_dead(void)
 322 {
 323         int cpu = cpu_number_map(cvmx_get_core_num());
 324
 325         idle_task_exit();
 326         octeon_processor_boot = 0xff;
 327         per_cpu(cpu_state, cpu) = CPU_DEAD;
 328
 329         mb();
 330
 331         while (1)       /* core will be reset here */
 332                 ;
 333 }
 334
 335 extern void kernel_entry(unsigned long arg1, ...);
 336
 337 static void start_after_reset(void)
 338 {
 339         kernel_entry(0, 0, 0);  /* set a2 = 0 for secondary core */
 340 }
 341
 342 static int octeon_update_boot_vector(unsigned int cpu)
 343 {
 344
 345         int coreid = cpu_logical_map(cpu);
 346         uint32_t avail_coremask;
 347         const struct cvmx_bootmem_named_block_desc *block_desc;
 348         struct boot_init_vector *boot_vect =
 349                 (struct boot_init_vector *)PHYS_TO_XKSEG_CACHED(BOOTLOADER_BOOT_VECTOR);
 350
 351         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 352
 353         if (!block_desc) {
 354                 struct linux_app_boot_info *labi;
 355
 356                 labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 357
 358                 avail_coremask = labi->avail_coremask;
 359                 labi->avail_coremask &= ~(1 << coreid);
 360         } else {                       /* alternative, already initialized */
 361                 avail_coremask = *(uint32_t *)PHYS_TO_XKSEG_CACHED(
 362                         block_desc->base_addr + AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
 363         }
 364
 365         if (!(avail_coremask & (1 << coreid))) {
 366                 /* core not available, assume, that caught by simple-executive */
 367                 cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 368                 cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 369         }
 370
 371         boot_vect[coreid].app_start_func_addr =
 372                 (uint32_t) (unsigned long) start_after_reset;
 373         boot_vect[coreid].code_addr = octeon_bootloader_entry_addr;
 374
 375         mb();
 376
 377         cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
 378
 379         return 0;
 380 }
 381
 382 static int octeon_cpu_callback(struct notifier_block *nfb,
 383         unsigned long action, void *hcpu)
 384 {
 385         unsigned int cpu = (unsigned long)hcpu;
 386
 387         switch (action & ~CPU_TASKS_FROZEN) {
 388         case CPU_UP_PREPARE:
 389                 octeon_update_boot_vector(cpu);
 390                 break;
 391         case CPU_ONLINE:
 392                 pr_info("Cpu %d online\n", cpu);
 393                 break;
 394         case CPU_DEAD:
 395                 break;
 396         }
 397
 398         return NOTIFY_OK;
 399 }
 400
 401 static int register_cavium_notifier(void)
 402 {
 403         hotcpu_notifier(octeon_cpu_callback, 0);
 404         return 0;
 405 }
 406 late_initcall(register_cavium_notifier);
 407
 408 #endif  /* CONFIG_HOTPLUG_CPU */
 409
 410 struct plat_smp_ops octeon_smp_ops = {
 411         .send_ipi_single        = octeon_send_ipi_single,
 412         .send_ipi_mask          = octeon_send_ipi_mask,
 413         .init_secondary         = octeon_init_secondary,
 414         .smp_finish             = octeon_smp_finish,
 415         .boot_secondary         = octeon_boot_secondary,
 416         .smp_setup              = octeon_smp_setup,
 417         .prepare_cpus           = octeon_prepare_cpus,
 418 #ifdef CONFIG_HOTPLUG_CPU
 419         .cpu_disable            = octeon_cpu_disable,
 420         .cpu_die                = octeon_cpu_die,
 421 #endif
 422 };
 423
 424 static irqreturn_t octeon_78xx_reched_interrupt(int irq, void *dev_id)
 425 {
 426         scheduler_ipi();
 427         return IRQ_HANDLED;
 428 }
 429
 430 static irqreturn_t octeon_78xx_call_function_interrupt(int irq, void *dev_id)
 431 {
 432         generic_smp_call_function_interrupt();
 433         return IRQ_HANDLED;
 434 }
 435
 436 static irqreturn_t octeon_78xx_icache_flush_interrupt(int irq, void *dev_id)
 437 {
 438         octeon_icache_flush();
 439         return IRQ_HANDLED;
 440 }
 441
 442 /*
 443  * Callout to firmware before smp_init
 444  */
 445 static void octeon_78xx_prepare_cpus(unsigned int max_cpus)
 446 {
 447         if (request_irq(OCTEON_IRQ_MBOX0 + 0,
 448                         octeon_78xx_reched_interrupt,
 449                         IRQF_PERCPU | IRQF_NO_THREAD, "Scheduler",
 450                         octeon_78xx_reched_interrupt)) {
 451                 panic("Cannot request_irq for SchedulerIPI");
 452         }
 453         if (request_irq(OCTEON_IRQ_MBOX0 + 1,
 454                         octeon_78xx_call_function_interrupt,
 455                         IRQF_PERCPU | IRQF_NO_THREAD, "SMP-Call",
 456                         octeon_78xx_call_function_interrupt)) {
 457                 panic("Cannot request_irq for SMP-Call");
 458         }
 459         if (request_irq(OCTEON_IRQ_MBOX0 + 2,
 460                         octeon_78xx_icache_flush_interrupt,
 461                         IRQF_PERCPU | IRQF_NO_THREAD, "ICache-Flush",
 462                         octeon_78xx_icache_flush_interrupt)) {
 463                 panic("Cannot request_irq for ICache-Flush");
 464         }
 465 }
 466
 467 static void octeon_78xx_send_ipi_single(int cpu, unsigned int action)
 468 {
 469         int i;
 470
 471         for (i = 0; i < 8; i++) {
 472                 if (action & 1)
 473                         octeon_ciu3_mbox_send(cpu, i);
 474                 action >>= 1;
 475         }
 476 }
 477
 478 static void octeon_78xx_send_ipi_mask(const struct cpumask *mask,
 479                                       unsigned int action)
 480 {
 481         unsigned int cpu;
 482
 483         for_each_cpu(cpu, mask)
 484                 octeon_78xx_send_ipi_single(cpu, action);
 485 }
 486
 487 static struct plat_smp_ops octeon_78xx_smp_ops = {
 488         .send_ipi_single        = octeon_78xx_send_ipi_single,
 489         .send_ipi_mask          = octeon_78xx_send_ipi_mask,
 490         .init_secondary         = octeon_init_secondary,
 491         .smp_finish             = octeon_smp_finish,
 492         .boot_secondary         = octeon_boot_secondary,
 493         .smp_setup              = octeon_smp_setup,
 494         .prepare_cpus           = octeon_78xx_prepare_cpus,
 495 #ifdef CONFIG_HOTPLUG_CPU
 496         .cpu_disable            = octeon_cpu_disable,
 497         .cpu_die                = octeon_cpu_die,
 498 #endif
 499 };
 500
 501 void __init octeon_setup_smp(void)
 502 {
 503         struct plat_smp_ops *ops;
 504
 505         if (octeon_has_feature(OCTEON_FEATURE_CIU3))
 506                 ops = &octeon_78xx_smp_ops;
 507         else
 508                 ops = &octeon_smp_ops;
 509
 510         register_smp_ops(ops);
 511 }