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/sched/task_stack.h>
  16 #include <linux/init.h>
  17 #include <linux/export.h>
  18
  19 #include <asm/mmu_context.h>
  20 #include <asm/time.h>
  21 #include <asm/setup.h>
  22
  23 #include <asm/octeon/octeon.h>
  24
  25 #include "octeon_boot.h"
  26
  27 volatile unsigned long octeon_processor_boot = 0xff;
  28 volatile unsigned long octeon_processor_sp;
  29 volatile unsigned long octeon_processor_gp;
  30 #ifdef CONFIG_RELOCATABLE
  31 volatile unsigned long octeon_processor_relocated_kernel_entry;
  32 #endif /* CONFIG_RELOCATABLE */
  33
  34 #ifdef CONFIG_HOTPLUG_CPU
  35 uint64_t octeon_bootloader_entry_addr;
  36 EXPORT_SYMBOL(octeon_bootloader_entry_addr);
  37 #endif
  38
  39 extern void kernel_entry(unsigned long arg1, ...);
  40
  41 static void octeon_icache_flush(void)
  42 {
  43         asm volatile ("synci 0($0)\n");
  44 }
  45
  46 static void (*octeon_message_functions[8])(void) = {
  47         scheduler_ipi,
  48         generic_smp_call_function_interrupt,
  49         octeon_icache_flush,
  50 };
  51
  52 static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
  53 {
  54         u64 mbox_clrx = CVMX_CIU_MBOX_CLRX(cvmx_get_core_num());
  55         u64 action;
  56         int i;
  57
  58         /*
  59          * Make sure the function array initialization remains
  60          * correct.
  61          */
  62         BUILD_BUG_ON(SMP_RESCHEDULE_YOURSELF != (1 << 0));
  63         BUILD_BUG_ON(SMP_CALL_FUNCTION       != (1 << 1));
  64         BUILD_BUG_ON(SMP_ICACHE_FLUSH        != (1 << 2));
  65
  66         /*
  67          * Load the mailbox register to figure out what we're supposed
  68          * to do.
  69          */
  70         action = cvmx_read_csr(mbox_clrx);
  71
  72         if (OCTEON_IS_MODEL(OCTEON_CN68XX))
  73                 action &= 0xff;
  74         else
  75                 action &= 0xffff;
  76
  77         /* Clear the mailbox to clear the interrupt */
  78         cvmx_write_csr(mbox_clrx, action);
  79
  80         for (i = 0; i < ARRAY_SIZE(octeon_message_functions) && action;) {
  81                 if (action & 1) {
  82                         void (*fn)(void) = octeon_message_functions[i];
  83
  84                         if (fn)
  85                                 fn();
  86                 }
  87                 action >>= 1;
  88                 i++;
  89         }
  90         return IRQ_HANDLED;
  91 }
  92
  93 /**
  94  * Cause the function described by call_data to be executed on the passed
  95  * cpu.  When the function has finished, increment the finished field of
  96  * call_data.
  97  */
  98 void octeon_send_ipi_single(int cpu, unsigned int action)
  99 {
 100         int coreid = cpu_logical_map(cpu);
 101         /*
 102         pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
 103                coreid, action);
 104         */
 105         cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
 106 }
 107
 108 static inline void octeon_send_ipi_mask(const struct cpumask *mask,
 109                                         unsigned int action)
 110 {
 111         unsigned int i;
 112
 113         for_each_cpu(i, mask)
 114                 octeon_send_ipi_single(i, action);
 115 }
 116
 117 /**
 118  * Detect available CPUs, populate cpu_possible_mask
 119  */
 120 static void octeon_smp_hotplug_setup(void)
 121 {
 122 #ifdef CONFIG_HOTPLUG_CPU
 123         struct linux_app_boot_info *labi;
 124
 125         if (!setup_max_cpus)
 126                 return;
 127
 128         labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 129         if (labi->labi_signature != LABI_SIGNATURE) {
 130                 pr_info("The bootloader on this board does not support HOTPLUG_CPU.");
 131                 return;
 132         }
 133
 134         octeon_bootloader_entry_addr = labi->InitTLBStart_addr;
 135 #endif
 136 }
 137
 138 static void __init octeon_smp_setup(void)
 139 {
 140         const int coreid = cvmx_get_core_num();
 141         int cpus;
 142         int id;
 143         struct cvmx_sysinfo *sysinfo = cvmx_sysinfo_get();
 144
 145 #ifdef CONFIG_HOTPLUG_CPU
 146         int core_mask = octeon_get_boot_coremask();
 147         unsigned int num_cores = cvmx_octeon_num_cores();
 148 #endif
 149
 150         /* The present CPUs are initially just the boot cpu (CPU 0). */
 151         for (id = 0; id < NR_CPUS; id++) {
 152                 set_cpu_possible(id, id == 0);
 153                 set_cpu_present(id, id == 0);
 154         }
 155
 156         __cpu_number_map[coreid] = 0;
 157         __cpu_logical_map[0] = coreid;
 158
 159         /* The present CPUs get the lowest CPU numbers. */
 160         cpus = 1;
 161         for (id = 0; id < NR_CPUS; id++) {
 162                 if ((id != coreid) && cvmx_coremask_is_core_set(&sysinfo->core_mask, id)) {
 163                         set_cpu_possible(cpus, true);
 164                         set_cpu_present(cpus, true);
 165                         __cpu_number_map[id] = cpus;
 166                         __cpu_logical_map[cpus] = id;
 167                         cpus++;
 168                 }
 169         }
 170
 171 #ifdef CONFIG_HOTPLUG_CPU
 172         /*
 173          * The possible CPUs are all those present on the chip.  We
 174          * will assign CPU numbers for possible cores as well.  Cores
 175          * are always consecutively numberd from 0.
 176          */
 177         for (id = 0; setup_max_cpus && octeon_bootloader_entry_addr &&
 178                      id < num_cores && id < NR_CPUS; id++) {
 179                 if (!(core_mask & (1 << id))) {
 180                         set_cpu_possible(cpus, true);
 181                         __cpu_number_map[id] = cpus;
 182                         __cpu_logical_map[cpus] = id;
 183                         cpus++;
 184                 }
 185         }
 186 #endif
 187
 188         octeon_smp_hotplug_setup();
 189 }
 190
 191
 192 #ifdef CONFIG_RELOCATABLE
 193 int plat_post_relocation(long offset)
 194 {
 195         unsigned long entry = (unsigned long)kernel_entry;
 196
 197         /* Send secondaries into relocated kernel */
 198         octeon_processor_relocated_kernel_entry = entry + offset;
 199
 200         return 0;
 201 }
 202 #endif /* CONFIG_RELOCATABLE */
 203
 204 /**
 205  * Firmware CPU startup hook
 206  *
 207  */
 208 static int octeon_boot_secondary(int cpu, struct task_struct *idle)
 209 {
 210         int count;
 211
 212         pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
 213                 cpu_logical_map(cpu));
 214
 215         octeon_processor_sp = __KSTK_TOS(idle);
 216         octeon_processor_gp = (unsigned long)(task_thread_info(idle));
 217         octeon_processor_boot = cpu_logical_map(cpu);
 218         mb();
 219
 220         count = 10000;
 221         while (octeon_processor_sp && count) {
 222                 /* Waiting for processor to get the SP and GP */
 223                 udelay(1);
 224                 count--;
 225         }
 226         if (count == 0) {
 227                 pr_err("Secondary boot timeout\n");
 228                 return -ETIMEDOUT;
 229         }
 230
 231         return 0;
 232 }
 233
 234 /**
 235  * After we've done initial boot, this function is called to allow the
 236  * board code to clean up state, if needed
 237  */
 238 static void octeon_init_secondary(void)
 239 {
 240         unsigned int sr;
 241
 242         sr = set_c0_status(ST0_BEV);
 243         write_c0_ebase((u32)ebase);
 244         write_c0_status(sr);
 245
 246         octeon_check_cpu_bist();
 247         octeon_init_cvmcount();
 248
 249         octeon_irq_setup_secondary();
 250 }
 251
 252 /**
 253  * Callout to firmware before smp_init
 254  *
 255  */
 256 static void __init octeon_prepare_cpus(unsigned int max_cpus)
 257 {
 258         /*
 259          * Only the low order mailbox bits are used for IPIs, leave
 260          * the other bits alone.
 261          */
 262         cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffff);
 263         if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt,
 264                         IRQF_PERCPU | IRQF_NO_THREAD, "SMP-IPI",
 265                         mailbox_interrupt)) {
 266                 panic("Cannot request_irq(OCTEON_IRQ_MBOX0)");
 267         }
 268 }
 269
 270 /**
 271  * Last chance for the board code to finish SMP initialization before
 272  * the CPU is "online".
 273  */
 274 static void octeon_smp_finish(void)
 275 {
 276         octeon_user_io_init();
 277
 278         /* to generate the first CPU timer interrupt */
 279         write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
 280         local_irq_enable();
 281 }
 282
 283 #ifdef CONFIG_HOTPLUG_CPU
 284
 285 /* State of each CPU. */
 286 DEFINE_PER_CPU(int, cpu_state);
 287
 288 static int octeon_cpu_disable(void)
 289 {
 290         unsigned int cpu = smp_processor_id();
 291
 292         if (cpu == 0)
 293                 return -EBUSY;
 294
 295         if (!octeon_bootloader_entry_addr)
 296                 return -ENOTSUPP;
 297
 298         set_cpu_online(cpu, false);
 299         calculate_cpu_foreign_map();
 300         octeon_fixup_irqs();
 301
 302         __flush_cache_all();
 303         local_flush_tlb_all();
 304
 305         return 0;
 306 }
 307
 308 static void octeon_cpu_die(unsigned int cpu)
 309 {
 310         int coreid = cpu_logical_map(cpu);
 311         uint32_t mask, new_mask;
 312         const struct cvmx_bootmem_named_block_desc *block_desc;
 313
 314         while (per_cpu(cpu_state, cpu) != CPU_DEAD)
 315                 cpu_relax();
 316
 317         /*
 318          * This is a bit complicated strategics of getting/settig available
 319          * cores mask, copied from bootloader
 320          */
 321
 322         mask = 1 << coreid;
 323         /* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
 324         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 325
 326         if (!block_desc) {
 327                 struct linux_app_boot_info *labi;
 328
 329                 labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 330
 331                 labi->avail_coremask |= mask;
 332                 new_mask = labi->avail_coremask;
 333         } else {                       /* alternative, already initialized */
 334                 uint32_t *p = (uint32_t *)PHYS_TO_XKSEG_CACHED(block_desc->base_addr +
 335                                                                AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
 336                 *p |= mask;
 337                 new_mask = *p;
 338         }
 339
 340         pr_info("Reset core %d. Available Coremask = 0x%x \n", coreid, new_mask);
 341         mb();
 342         cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 343         cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 344 }
 345
 346 void play_dead(void)
 347 {
 348         int cpu = cpu_number_map(cvmx_get_core_num());
 349
 350         idle_task_exit();
 351         octeon_processor_boot = 0xff;
 352         per_cpu(cpu_state, cpu) = CPU_DEAD;
 353
 354         mb();
 355
 356         while (1)       /* core will be reset here */
 357                 ;
 358 }
 359
 360 static void start_after_reset(void)
 361 {
 362         kernel_entry(0, 0, 0);  /* set a2 = 0 for secondary core */
 363 }
 364
 365 static int octeon_update_boot_vector(unsigned int cpu)
 366 {
 367
 368         int coreid = cpu_logical_map(cpu);
 369         uint32_t avail_coremask;
 370         const struct cvmx_bootmem_named_block_desc *block_desc;
 371         struct boot_init_vector *boot_vect =
 372                 (struct boot_init_vector *)PHYS_TO_XKSEG_CACHED(BOOTLOADER_BOOT_VECTOR);
 373
 374         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 375
 376         if (!block_desc) {
 377                 struct linux_app_boot_info *labi;
 378
 379                 labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
 380
 381                 avail_coremask = labi->avail_coremask;
 382                 labi->avail_coremask &= ~(1 << coreid);
 383         } else {                       /* alternative, already initialized */
 384                 avail_coremask = *(uint32_t *)PHYS_TO_XKSEG_CACHED(
 385                         block_desc->base_addr + AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
 386         }
 387
 388         if (!(avail_coremask & (1 << coreid))) {
 389                 /* core not available, assume, that caught by simple-executive */
 390                 cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 391                 cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 392         }
 393
 394         boot_vect[coreid].app_start_func_addr =
 395                 (uint32_t) (unsigned long) start_after_reset;
 396         boot_vect[coreid].code_addr = octeon_bootloader_entry_addr;
 397
 398         mb();
 399
 400         cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
 401
 402         return 0;
 403 }
 404
 405 static int register_cavium_notifier(void)
 406 {
 407         return cpuhp_setup_state_nocalls(CPUHP_MIPS_SOC_PREPARE,
 408                                          "mips/cavium:prepare",
 409                                          octeon_update_boot_vector, NULL);
 410 }
 411 late_initcall(register_cavium_notifier);
 412
 413 #endif  /* CONFIG_HOTPLUG_CPU */
 414
 415 const struct plat_smp_ops octeon_smp_ops = {
 416         .send_ipi_single        = octeon_send_ipi_single,
 417         .send_ipi_mask          = octeon_send_ipi_mask,
 418         .init_secondary         = octeon_init_secondary,
 419         .smp_finish             = octeon_smp_finish,
 420         .boot_secondary         = octeon_boot_secondary,
 421         .smp_setup              = octeon_smp_setup,
 422         .prepare_cpus           = octeon_prepare_cpus,
 423 #ifdef CONFIG_HOTPLUG_CPU
 424         .cpu_disable            = octeon_cpu_disable,
 425         .cpu_die                = octeon_cpu_die,
 426 #endif
 427 };
 428
 429 static irqreturn_t octeon_78xx_reched_interrupt(int irq, void *dev_id)
 430 {
 431         scheduler_ipi();
 432         return IRQ_HANDLED;
 433 }
 434
 435 static irqreturn_t octeon_78xx_call_function_interrupt(int irq, void *dev_id)
 436 {
 437         generic_smp_call_function_interrupt();
 438         return IRQ_HANDLED;
 439 }
 440
 441 static irqreturn_t octeon_78xx_icache_flush_interrupt(int irq, void *dev_id)
 442 {
 443         octeon_icache_flush();
 444         return IRQ_HANDLED;
 445 }
 446
 447 /*
 448  * Callout to firmware before smp_init
 449  */
 450 static void octeon_78xx_prepare_cpus(unsigned int max_cpus)
 451 {
 452         if (request_irq(OCTEON_IRQ_MBOX0 + 0,
 453                         octeon_78xx_reched_interrupt,
 454                         IRQF_PERCPU | IRQF_NO_THREAD, "Scheduler",
 455                         octeon_78xx_reched_interrupt)) {
 456                 panic("Cannot request_irq for SchedulerIPI");
 457         }
 458         if (request_irq(OCTEON_IRQ_MBOX0 + 1,
 459                         octeon_78xx_call_function_interrupt,
 460                         IRQF_PERCPU | IRQF_NO_THREAD, "SMP-Call",
 461                         octeon_78xx_call_function_interrupt)) {
 462                 panic("Cannot request_irq for SMP-Call");
 463         }
 464         if (request_irq(OCTEON_IRQ_MBOX0 + 2,
 465                         octeon_78xx_icache_flush_interrupt,
 466                         IRQF_PERCPU | IRQF_NO_THREAD, "ICache-Flush",
 467                         octeon_78xx_icache_flush_interrupt)) {
 468                 panic("Cannot request_irq for ICache-Flush");
 469         }
 470 }
 471
 472 static void octeon_78xx_send_ipi_single(int cpu, unsigned int action)
 473 {
 474         int i;
 475
 476         for (i = 0; i < 8; i++) {
 477                 if (action & 1)
 478                         octeon_ciu3_mbox_send(cpu, i);
 479                 action >>= 1;
 480         }
 481 }
 482
 483 static void octeon_78xx_send_ipi_mask(const struct cpumask *mask,
 484                                       unsigned int action)
 485 {
 486         unsigned int cpu;
 487
 488         for_each_cpu(cpu, mask)
 489                 octeon_78xx_send_ipi_single(cpu, action);
 490 }
 491
 492 static const struct plat_smp_ops octeon_78xx_smp_ops = {
 493         .send_ipi_single        = octeon_78xx_send_ipi_single,
 494         .send_ipi_mask          = octeon_78xx_send_ipi_mask,
 495         .init_secondary         = octeon_init_secondary,
 496         .smp_finish             = octeon_smp_finish,
 497         .boot_secondary         = octeon_boot_secondary,
 498         .smp_setup              = octeon_smp_setup,
 499         .prepare_cpus           = octeon_78xx_prepare_cpus,
 500 #ifdef CONFIG_HOTPLUG_CPU
 501         .cpu_disable            = octeon_cpu_disable,
 502         .cpu_die                = octeon_cpu_die,
 503 #endif
 504 };
 505
 506 void __init octeon_setup_smp(void)
 507 {
 508         const struct plat_smp_ops *ops;
 509
 510         if (octeon_has_feature(OCTEON_FEATURE_CIU3))
 511                 ops = &octeon_78xx_smp_ops;
 512         else
 513                 ops = &octeon_smp_ops;
 514
 515         register_smp_ops(ops);
 516 }