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/sched/hotplug.h>
  15 #include <linux/init.h>
  16 #include <linux/export.h>
  17
  18 #include <asm/mmu_context.h>
  19 #include <asm/time.h>
  20 #include <asm/setup.h>
  21
  22 #include <asm/octeon/octeon.h>
  23
  24 #include "octeon_boot.h"
  25
  26 volatile unsigned long octeon_processor_boot = 0xff;
  27 volatile unsigned long octeon_processor_sp;
  28 volatile unsigned long octeon_processor_gp;
  29 #ifdef CONFIG_RELOCATABLE
  30 volatile unsigned long octeon_processor_relocated_kernel_entry;
  31 #endif /* CONFIG_RELOCATABLE */
  32
  33 #ifdef CONFIG_HOTPLUG_CPU
  34 uint64_t octeon_bootloader_entry_addr;
  35 EXPORT_SYMBOL(octeon_bootloader_entry_addr);
  36 #endif
  37
  38 extern void kernel_entry(unsigned long arg1, ...);
  39
  40 static void octeon_icache_flush(void)
  41 {
  42         asm volatile ("synci 0($0)\n");
  43 }
  44
  45 static void (*octeon_message_functions[8])(void) = {
  46         scheduler_ipi,
  47         generic_smp_call_function_interrupt,
  48         octeon_icache_flush,
  49 };
  50
  51 static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
  52 {
  53         u64 mbox_clrx = CVMX_CIU_MBOX_CLRX(cvmx_get_core_num());
  54         u64 action;
  55         int i;
  56
  57         /*
  58          * Make sure the function array initialization remains
  59          * correct.
  60          */
  61         BUILD_BUG_ON(SMP_RESCHEDULE_YOURSELF != (1 << 0));
  62         BUILD_BUG_ON(SMP_CALL_FUNCTION       != (1 << 1));
  63         BUILD_BUG_ON(SMP_ICACHE_FLUSH        != (1 << 2));
  64
  65         /*
  66          * Load the mailbox register to figure out what we're supposed
  67          * to do.
  68          */
  69         action = cvmx_read_csr(mbox_clrx);
  70
  71         if (OCTEON_IS_MODEL(OCTEON_CN68XX))
  72                 action &= 0xff;
  73         else
  74                 action &= 0xffff;
  75
  76         /* Clear the mailbox to clear the interrupt */
  77         cvmx_write_csr(mbox_clrx, action);
  78
  79         for (i = 0; i < ARRAY_SIZE(octeon_message_functions) && action;) {
  80                 if (action & 1) {
  81                         void (*fn)(void) = octeon_message_functions[i];
  82
  83                         if (fn)
  84                                 fn();
  85                 }
  86                 action >>= 1;
  87                 i++;
  88         }
  89         return IRQ_HANDLED;
  90 }
  91
  92 /**
  93  * Cause the function described by call_data to be executed on the passed
  94  * cpu.  When the function has finished, increment the finished field of
  95  * call_data.
  96  */
  97 void octeon_send_ipi_single(int cpu, unsigned int action)
  98 {
  99         int coreid = cpu_logical_map(cpu);
 100         /*
 101         pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
 102                coreid, action);
 103         */
 104         cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
 105 }
 106
 107 static inline void octeon_send_ipi_mask(const struct cpumask *mask,
 108                                         unsigned int action)
 109 {
 110         unsigned int i;
 111
 112         for_each_cpu(i, mask)
 113                 octeon_send_ipi_single(i, action);
 114 }
 115
 116 /**
 117  * Detect available CPUs, populate cpu_possible_mask
 118  */
 119 static void octeon_smp_hotplug_setup(void)
 120 {
 121 #ifdef CONFIG_HOTPLUG_CPU
 122         struct linux_app_boot_info *labi;
 123
 124         if (!setup_max_cpus)
 125                 return;
 126
 127         labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 128         if (labi->labi_signature != LABI_SIGNATURE) {
 129                 pr_info("The bootloader on this board does not support HOTPLUG_CPU.");
 130                 return;
 131         }
 132
 133         octeon_bootloader_entry_addr = labi->InitTLBStart_addr;
 134 #endif
 135 }
 136
 137 static void __init octeon_smp_setup(void)
 138 {
 139         const int coreid = cvmx_get_core_num();
 140         int cpus;
 141         int id;
 142         struct cvmx_sysinfo *sysinfo = cvmx_sysinfo_get();
 143
 144 #ifdef CONFIG_HOTPLUG_CPU
 145         int core_mask = octeon_get_boot_coremask();
 146         unsigned int num_cores = cvmx_octeon_num_cores();
 147 #endif
 148
 149         /* The present CPUs are initially just the boot cpu (CPU 0). */
 150         for (id = 0; id < NR_CPUS; id++) {
 151                 set_cpu_possible(id, id == 0);
 152                 set_cpu_present(id, id == 0);
 153         }
 154
 155         __cpu_number_map[coreid] = 0;
 156         __cpu_logical_map[0] = coreid;
 157
 158         /* The present CPUs get the lowest CPU numbers. */
 159         cpus = 1;
 160         for (id = 0; id < NR_CPUS; id++) {
 161                 if ((id != coreid) && cvmx_coremask_is_core_set(&sysinfo->core_mask, id)) {
 162                         set_cpu_possible(cpus, true);
 163                         set_cpu_present(cpus, true);
 164                         __cpu_number_map[id] = cpus;
 165                         __cpu_logical_map[cpus] = id;
 166                         cpus++;
 167                 }
 168         }
 169
 170 #ifdef CONFIG_HOTPLUG_CPU
 171         /*
 172          * The possible CPUs are all those present on the chip.  We
 173          * will assign CPU numbers for possible cores as well.  Cores
 174          * are always consecutively numberd from 0.
 175          */
 176         for (id = 0; setup_max_cpus && octeon_bootloader_entry_addr &&
 177                      id < num_cores && id < NR_CPUS; id++) {
 178                 if (!(core_mask & (1 << id))) {
 179                         set_cpu_possible(cpus, true);
 180                         __cpu_number_map[id] = cpus;
 181                         __cpu_logical_map[cpus] = id;
 182                         cpus++;
 183                 }
 184         }
 185 #endif
 186
 187         octeon_smp_hotplug_setup();
 188 }
 189
 190
 191 #ifdef CONFIG_RELOCATABLE
 192 int plat_post_relocation(long offset)
 193 {
 194         unsigned long entry = (unsigned long)kernel_entry;
 195
 196         /* Send secondaries into relocated kernel */
 197         octeon_processor_relocated_kernel_entry = entry + offset;
 198
 199         return 0;
 200 }
 201 #endif /* CONFIG_RELOCATABLE */
 202
 203 /**
 204  * Firmware CPU startup hook
 205  *
 206  */
 207 static void octeon_boot_secondary(int cpu, struct task_struct *idle)
 208 {
 209         int count;
 210
 211         pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
 212                 cpu_logical_map(cpu));
 213
 214         octeon_processor_sp = __KSTK_TOS(idle);
 215         octeon_processor_gp = (unsigned long)(task_thread_info(idle));
 216         octeon_processor_boot = cpu_logical_map(cpu);
 217         mb();
 218
 219         count = 10000;
 220         while (octeon_processor_sp && count) {
 221                 /* Waiting for processor to get the SP and GP */
 222                 udelay(1);
 223                 count--;
 224         }
 225         if (count == 0)
 226                 pr_err("Secondary boot timeout\n");
 227 }
 228
 229 /**
 230  * After we've done initial boot, this function is called to allow the
 231  * board code to clean up state, if needed
 232  */
 233 static void octeon_init_secondary(void)
 234 {
 235         unsigned int sr;
 236
 237         sr = set_c0_status(ST0_BEV);
 238         write_c0_ebase((u32)ebase);
 239         write_c0_status(sr);
 240
 241         octeon_check_cpu_bist();
 242         octeon_init_cvmcount();
 243
 244         octeon_irq_setup_secondary();
 245 }
 246
 247 /**
 248  * Callout to firmware before smp_init
 249  *
 250  */
 251 static void __init octeon_prepare_cpus(unsigned int max_cpus)
 252 {
 253         /*
 254          * Only the low order mailbox bits are used for IPIs, leave
 255          * the other bits alone.
 256          */
 257         cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffff);
 258         if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt,
 259                         IRQF_PERCPU | IRQF_NO_THREAD, "SMP-IPI",
 260                         mailbox_interrupt)) {
 261                 panic("Cannot request_irq(OCTEON_IRQ_MBOX0)");
 262         }
 263 }
 264
 265 /**
 266  * Last chance for the board code to finish SMP initialization before
 267  * the CPU is "online".
 268  */
 269 static void octeon_smp_finish(void)
 270 {
 271         octeon_user_io_init();
 272
 273         /* to generate the first CPU timer interrupt */
 274         write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
 275         local_irq_enable();
 276 }
 277
 278 #ifdef CONFIG_HOTPLUG_CPU
 279
 280 /* State of each CPU. */
 281 DEFINE_PER_CPU(int, cpu_state);
 282
 283 static int octeon_cpu_disable(void)
 284 {
 285         unsigned int cpu = smp_processor_id();
 286
 287         if (cpu == 0)
 288                 return -EBUSY;
 289
 290         if (!octeon_bootloader_entry_addr)
 291                 return -ENOTSUPP;
 292
 293         set_cpu_online(cpu, false);
 294         calculate_cpu_foreign_map();
 295         octeon_fixup_irqs();
 296
 297         __flush_cache_all();
 298         local_flush_tlb_all();
 299
 300         return 0;
 301 }
 302
 303 static void octeon_cpu_die(unsigned int cpu)
 304 {
 305         int coreid = cpu_logical_map(cpu);
 306         uint32_t mask, new_mask;
 307         const struct cvmx_bootmem_named_block_desc *block_desc;
 308
 309         while (per_cpu(cpu_state, cpu) != CPU_DEAD)
 310                 cpu_relax();
 311
 312         /*
 313          * This is a bit complicated strategics of getting/settig available
 314          * cores mask, copied from bootloader
 315          */
 316
 317         mask = 1 << coreid;
 318         /* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
 319         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 320
 321         if (!block_desc) {
 322                 struct linux_app_boot_info *labi;
 323
 324                 labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 325
 326                 labi->avail_coremask |= mask;
 327                 new_mask = labi->avail_coremask;
 328         } else {                       /* alternative, already initialized */
 329                 uint32_t *p = (uint32_t *)PHYS_TO_XKSEG_CACHED(block_desc->base_addr +
 330                                                                AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
 331                 *p |= mask;
 332                 new_mask = *p;
 333         }
 334
 335         pr_info("Reset core %d. Available Coremask = 0x%x \n", coreid, new_mask);
 336         mb();
 337         cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 338         cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 339 }
 340
 341 void play_dead(void)
 342 {
 343         int cpu = cpu_number_map(cvmx_get_core_num());
 344
 345         idle_task_exit();
 346         octeon_processor_boot = 0xff;
 347         per_cpu(cpu_state, cpu) = CPU_DEAD;
 348
 349         mb();
 350
 351         while (1)       /* core will be reset here */
 352                 ;
 353 }
 354
 355 static void start_after_reset(void)
 356 {
 357         kernel_entry(0, 0, 0);  /* set a2 = 0 for secondary core */
 358 }
 359
 360 static int octeon_update_boot_vector(unsigned int cpu)
 361 {
 362
 363         int coreid = cpu_logical_map(cpu);
 364         uint32_t avail_coremask;
 365         const struct cvmx_bootmem_named_block_desc *block_desc;
 366         struct boot_init_vector *boot_vect =
 367                 (struct boot_init_vector *)PHYS_TO_XKSEG_CACHED(BOOTLOADER_BOOT_VECTOR);
 368
 369         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 370
 371         if (!block_desc) {
 372                 struct linux_app_boot_info *labi;
 373
 374                 labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 375
 376                 avail_coremask = labi->avail_coremask;
 377                 labi->avail_coremask &= ~(1 << coreid);
 378         } else {                       /* alternative, already initialized */
 379                 avail_coremask = *(uint32_t *)PHYS_TO_XKSEG_CACHED(
 380                         block_desc->base_addr + AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
 381         }
 382
 383         if (!(avail_coremask & (1 << coreid))) {
 384                 /* core not available, assume, that caught by simple-executive */
 385                 cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 386                 cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 387         }
 388
 389         boot_vect[coreid].app_start_func_addr =
 390                 (uint32_t) (unsigned long) start_after_reset;
 391         boot_vect[coreid].code_addr = octeon_bootloader_entry_addr;
 392
 393         mb();
 394
 395         cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
 396
 397         return 0;
 398 }
 399
 400 static int register_cavium_notifier(void)
 401 {
 402         return cpuhp_setup_state_nocalls(CPUHP_MIPS_SOC_PREPARE,
 403                                          "mips/cavium:prepare",
 404                                          octeon_update_boot_vector, NULL);
 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 }