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 Cavium Networks
   7  */
   8 #include <linux/cpu.h>
   9 #include <linux/init.h>
  10 #include <linux/delay.h>
  11 #include <linux/smp.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/kernel_stat.h>
  14 #include <linux/sched.h>
  15 #include <linux/module.h>
  16
  17 #include <asm/mmu_context.h>
  18 #include <asm/system.h>
  19 #include <asm/time.h>
  20
  21 #include <asm/octeon/octeon.h>
  22
  23 #include "octeon_boot.h"
  24
  25 volatile unsigned long octeon_processor_boot = 0xff;
  26 volatile unsigned long octeon_processor_sp;
  27 volatile unsigned long octeon_processor_gp;
  28
  29 #ifdef CONFIG_HOTPLUG_CPU
  30 static unsigned int InitTLBStart_addr;
  31 #endif
  32
  33 static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
  34 {
  35         const int coreid = cvmx_get_core_num();
  36         uint64_t action;
  37
  38         /* Load the mailbox register to figure out what we're supposed to do */
  39         action = cvmx_read_csr(CVMX_CIU_MBOX_CLRX(coreid));
  40
  41         /* Clear the mailbox to clear the interrupt */
  42         cvmx_write_csr(CVMX_CIU_MBOX_CLRX(coreid), action);
  43
  44         if (action & SMP_CALL_FUNCTION)
  45                 smp_call_function_interrupt();
  46
  47         /* Check if we've been told to flush the icache */
  48         if (action & SMP_ICACHE_FLUSH)
  49                 asm volatile ("synci 0($0)\n");
  50         return IRQ_HANDLED;
  51 }
  52
  53 /**
  54  * Cause the function described by call_data to be executed on the passed
  55  * cpu.  When the function has finished, increment the finished field of
  56  * call_data.
  57  */
  58 void octeon_send_ipi_single(int cpu, unsigned int action)
  59 {
  60         int coreid = cpu_logical_map(cpu);
  61         /*
  62         pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
  63                coreid, action);
  64         */
  65         cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
  66 }
  67
  68 static inline void octeon_send_ipi_mask(const struct cpumask *mask,
  69                                         unsigned int action)
  70 {
  71         unsigned int i;
  72
  73         for_each_cpu_mask(i, *mask)
  74                 octeon_send_ipi_single(i, action);
  75 }
  76
  77 /**
  78  * Detect available CPUs, populate cpu_possible_map
  79  */
  80 static void octeon_smp_hotplug_setup(void)
  81 {
  82 #ifdef CONFIG_HOTPLUG_CPU
  83         uint32_t labi_signature;
  84
  85         labi_signature =
  86                 cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
  87                                         LABI_ADDR_IN_BOOTLOADER +
  88                                         offsetof(struct linux_app_boot_info,
  89                                                     labi_signature)));
  90         if (labi_signature != LABI_SIGNATURE)
  91                 pr_err("The bootloader version on this board is incorrect\n");
  92         InitTLBStart_addr =
  93                 cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
  94                                    LABI_ADDR_IN_BOOTLOADER +
  95                                            offsetof(struct linux_app_boot_info,
  96                                                     InitTLBStart_addr)));
  97 #endif
  98 }
  99
 100 static void octeon_smp_setup(void)
 101 {
 102         const int coreid = cvmx_get_core_num();
 103         int cpus;
 104         int id;
 105
 106         int core_mask = octeon_get_boot_coremask();
 107
 108         cpus_clear(cpu_possible_map);
 109         __cpu_number_map[coreid] = 0;
 110         __cpu_logical_map[0] = coreid;
 111         cpu_set(0, cpu_possible_map);
 112
 113         cpus = 1;
 114         for (id = 0; id < 16; id++) {
 115                 if ((id != coreid) && (core_mask & (1 << id))) {
 116                         cpu_set(cpus, cpu_possible_map);
 117                         __cpu_number_map[id] = cpus;
 118                         __cpu_logical_map[cpus] = id;
 119                         cpus++;
 120                 }
 121         }
 122         cpu_present_map = cpu_possible_map;
 123
 124         octeon_smp_hotplug_setup();
 125 }
 126
 127 /**
 128  * Firmware CPU startup hook
 129  *
 130  */
 131 static void octeon_boot_secondary(int cpu, struct task_struct *idle)
 132 {
 133         int count;
 134
 135         pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
 136                 cpu_logical_map(cpu));
 137
 138         octeon_processor_sp = __KSTK_TOS(idle);
 139         octeon_processor_gp = (unsigned long)(task_thread_info(idle));
 140         octeon_processor_boot = cpu_logical_map(cpu);
 141         mb();
 142
 143         count = 10000;
 144         while (octeon_processor_sp && count) {
 145                 /* Waiting for processor to get the SP and GP */
 146                 udelay(1);
 147                 count--;
 148         }
 149         if (count == 0)
 150                 pr_err("Secondary boot timeout\n");
 151 }
 152
 153 /**
 154  * After we've done initial boot, this function is called to allow the
 155  * board code to clean up state, if needed
 156  */
 157 static void octeon_init_secondary(void)
 158 {
 159         const int coreid = cvmx_get_core_num();
 160         union cvmx_ciu_intx_sum0 interrupt_enable;
 161
 162 #ifdef CONFIG_HOTPLUG_CPU
 163         unsigned int cur_exception_base;
 164
 165         cur_exception_base = cvmx_read64_uint32(
 166                 CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
 167                              LABI_ADDR_IN_BOOTLOADER +
 168                              offsetof(struct linux_app_boot_info,
 169                                       cur_exception_base)));
 170         /* cur_exception_base is incremented in bootloader after setting */
 171         write_c0_ebase((unsigned int)(cur_exception_base - EXCEPTION_BASE_INCR));
 172 #endif
 173         octeon_check_cpu_bist();
 174         octeon_init_cvmcount();
 175         /*
 176         pr_info("SMP: CPU%d (CoreId %lu) started\n", cpu, coreid);
 177         */
 178         /* Enable Mailbox interrupts to this core. These are the only
 179            interrupts allowed on line 3 */
 180         cvmx_write_csr(CVMX_CIU_MBOX_CLRX(coreid), 0xffffffff);
 181         interrupt_enable.u64 = 0;
 182         interrupt_enable.s.mbox = 0x3;
 183         cvmx_write_csr(CVMX_CIU_INTX_EN0((coreid * 2)), interrupt_enable.u64);
 184         cvmx_write_csr(CVMX_CIU_INTX_EN0((coreid * 2 + 1)), 0);
 185         cvmx_write_csr(CVMX_CIU_INTX_EN1((coreid * 2)), 0);
 186         cvmx_write_csr(CVMX_CIU_INTX_EN1((coreid * 2 + 1)), 0);
 187         /* Enable core interrupt processing for 2,3 and 7 */
 188         set_c0_status(0x8c01);
 189 }
 190
 191 /**
 192  * Callout to firmware before smp_init
 193  *
 194  */
 195 void octeon_prepare_cpus(unsigned int max_cpus)
 196 {
 197         cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffffffff);
 198         if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt, IRQF_DISABLED,
 199                         "mailbox0", mailbox_interrupt)) {
 200                 panic("Cannot request_irq(OCTEON_IRQ_MBOX0)\n");
 201         }
 202         if (request_irq(OCTEON_IRQ_MBOX1, mailbox_interrupt, IRQF_DISABLED,
 203                         "mailbox1", mailbox_interrupt)) {
 204                 panic("Cannot request_irq(OCTEON_IRQ_MBOX1)\n");
 205         }
 206 }
 207
 208 /**
 209  * Last chance for the board code to finish SMP initialization before
 210  * the CPU is "online".
 211  */
 212 static void octeon_smp_finish(void)
 213 {
 214 #ifdef CONFIG_CAVIUM_GDB
 215         unsigned long tmp;
 216         /* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
 217            to be not masked by this core so we know the signal is received by
 218            someone */
 219         asm volatile ("dmfc0 %0, $22\n"
 220                       "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
 221 #endif
 222
 223         octeon_user_io_init();
 224
 225         /* to generate the first CPU timer interrupt */
 226         write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
 227 }
 228
 229 /**
 230  * Hook for after all CPUs are online
 231  */
 232 static void octeon_cpus_done(void)
 233 {
 234 #ifdef CONFIG_CAVIUM_GDB
 235         unsigned long tmp;
 236         /* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
 237            to be not masked by this core so we know the signal is received by
 238            someone */
 239         asm volatile ("dmfc0 %0, $22\n"
 240                       "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
 241 #endif
 242 }
 243
 244 #ifdef CONFIG_HOTPLUG_CPU
 245
 246 /* State of each CPU. */
 247 DEFINE_PER_CPU(int, cpu_state);
 248
 249 extern void fixup_irqs(void);
 250
 251 static DEFINE_SPINLOCK(smp_reserve_lock);
 252
 253 static int octeon_cpu_disable(void)
 254 {
 255         unsigned int cpu = smp_processor_id();
 256
 257         if (cpu == 0)
 258                 return -EBUSY;
 259
 260         spin_lock(&smp_reserve_lock);
 261
 262         cpu_clear(cpu, cpu_online_map);
 263         cpu_clear(cpu, cpu_callin_map);
 264         local_irq_disable();
 265         fixup_irqs();
 266         local_irq_enable();
 267
 268         flush_cache_all();
 269         local_flush_tlb_all();
 270
 271         spin_unlock(&smp_reserve_lock);
 272
 273         return 0;
 274 }
 275
 276 static void octeon_cpu_die(unsigned int cpu)
 277 {
 278         int coreid = cpu_logical_map(cpu);
 279         uint32_t avail_coremask;
 280         struct cvmx_bootmem_named_block_desc *block_desc;
 281
 282         while (per_cpu(cpu_state, cpu) != CPU_DEAD)
 283                 cpu_relax();
 284
 285         /*
 286          * This is a bit complicated strategics of getting/settig available
 287          * cores mask, copied from bootloader
 288          */
 289         /* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
 290         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 291
 292         if (!block_desc) {
 293                 avail_coremask =
 294                         cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
 295                                                    LABI_ADDR_IN_BOOTLOADER +
 296                                                    offsetof
 297                                                    (struct linux_app_boot_info,
 298                                                     avail_coremask)));
 299         } else {                       /* alternative, already initialized */
 300                avail_coremask =
 301                    cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
 302                                                    block_desc->base_addr +
 303                                                   AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK));
 304         }
 305
 306         avail_coremask |= 1 << coreid;
 307
 308         /* Setting avail_coremask for bootoct binary */
 309         if (!block_desc) {
 310                 cvmx_write64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
 311                                                 LABI_ADDR_IN_BOOTLOADER +
 312                                                 offsetof(struct linux_app_boot_info,
 313                                                          avail_coremask)),
 314                                    avail_coremask);
 315         } else {
 316                 cvmx_write64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
 317                                                 block_desc->base_addr +
 318                                                 AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK),
 319                                    avail_coremask);
 320         }
 321
 322         pr_info("Reset core %d. Available Coremask = %x\n", coreid,
 323                 avail_coremask);
 324         cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 325         cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 326 }
 327
 328 void play_dead(void)
 329 {
 330         int coreid = cvmx_get_core_num();
 331
 332         idle_task_exit();
 333         octeon_processor_boot = 0xff;
 334         per_cpu(cpu_state, coreid) = CPU_DEAD;
 335
 336         while (1)       /* core will be reset here */
 337                 ;
 338 }
 339
 340 extern void kernel_entry(unsigned long arg1, ...);
 341
 342 static void start_after_reset(void)
 343 {
 344         kernel_entry(0, 0, 0);  /* set a2 = 0 for secondary core */
 345 }
 346
 347 int octeon_update_boot_vector(unsigned int cpu)
 348 {
 349
 350         int coreid = cpu_logical_map(cpu);
 351         unsigned int avail_coremask;
 352         struct cvmx_bootmem_named_block_desc *block_desc;
 353         struct boot_init_vector *boot_vect =
 354                 (struct boot_init_vector *) cvmx_phys_to_ptr(0x0 +
 355                                                   BOOTLOADER_BOOT_VECTOR);
 356
 357         block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
 358
 359         if (!block_desc) {
 360                 avail_coremask =
 361                         cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
 362                                            LABI_ADDR_IN_BOOTLOADER +
 363                                                 offsetof(struct linux_app_boot_info,
 364                                                 avail_coremask)));
 365         } else {                       /* alternative, already initialized */
 366                avail_coremask =
 367                    cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
 368                                                    block_desc->base_addr +
 369                                                    AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK));
 370         }
 371
 372         if (!(avail_coremask & (1 << coreid))) {
 373                 /* core not available, assume, that catched by simple-executive */
 374                 cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
 375                 cvmx_write_csr(CVMX_CIU_PP_RST, 0);
 376         }
 377
 378         boot_vect[coreid].app_start_func_addr =
 379                 (uint32_t) (unsigned long) start_after_reset;
 380         boot_vect[coreid].code_addr = InitTLBStart_addr;
 381
 382         CVMX_SYNC;
 383
 384         cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
 385
 386         return 0;
 387 }
 388
 389 static int __cpuinit octeon_cpu_callback(struct notifier_block *nfb,
 390         unsigned long action, void *hcpu)
 391 {
 392         unsigned int cpu = (unsigned long)hcpu;
 393
 394         switch (action) {
 395         case CPU_UP_PREPARE:
 396                 octeon_update_boot_vector(cpu);
 397                 break;
 398         case CPU_ONLINE:
 399                 pr_info("Cpu %d online\n", cpu);
 400                 break;
 401         case CPU_DEAD:
 402                 break;
 403         }
 404
 405         return NOTIFY_OK;
 406 }
 407
 408 static struct notifier_block __cpuinitdata octeon_cpu_notifier = {
 409         .notifier_call = octeon_cpu_callback,
 410 };
 411
 412 static int __cpuinit register_cavium_notifier(void)
 413 {
 414         register_hotcpu_notifier(&octeon_cpu_notifier);
 415
 416         return 0;
 417 }
 418
 419 late_initcall(register_cavium_notifier);
 420
 421 #endif  /* CONFIG_HOTPLUG_CPU */
 422
 423 struct plat_smp_ops octeon_smp_ops = {
 424         .send_ipi_single        = octeon_send_ipi_single,
 425         .send_ipi_mask          = octeon_send_ipi_mask,
 426         .init_secondary         = octeon_init_secondary,
 427         .smp_finish             = octeon_smp_finish,
 428         .cpus_done              = octeon_cpus_done,
 429         .boot_secondary         = octeon_boot_secondary,
 430         .smp_setup              = octeon_smp_setup,
 431         .prepare_cpus           = octeon_prepare_cpus,
 432 #ifdef CONFIG_HOTPLUG_CPU
 433         .cpu_disable            = octeon_cpu_disable,
 434         .cpu_die                = octeon_cpu_die,
 435 #endif
 436 };