LXR linux/arch/arm/mach-tango/platsmp.c

   1#include <linux/delay.h>
   2#include <linux/init.h>
   3#include <linux/smp.h>
   4#include "smc.h"
   5
   6static int tango_boot_secondary(unsigned int cpu, struct task_struct *idle)
   7{
   8        tango_set_aux_boot_addr(virt_to_phys(secondary_startup));
   9        tango_start_aux_core(cpu);
  10        return 0;
  11}
  12
  13#ifdef CONFIG_HOTPLUG_CPU
  14/*
  15 * cpu_kill() and cpu_die() run concurrently on different cores.
  16 * Firmware will only "kill" a core once it has properly "died".
  17 * Try a few times to kill a core before giving up, and sleep
  18 * between tries to give that core enough time to die.
  19 */
  20static int tango_cpu_kill(unsigned int cpu)
  21{
  22        int i, err;
  23
  24        for (i = 0; i < 10; ++i) {
  25                msleep(10);
  26                err = tango_aux_core_kill(cpu);
  27                if (!err)
  28                        return true;
  29        }
  30
  31        return false;
  32}
  33
  34static void tango_cpu_die(unsigned int cpu)
  35{
  36        while (tango_aux_core_die(cpu) < 0)
  37                cpu_relax();
  38
  39        panic("cpu %d failed to die\n", cpu);
  40}
  41#endif
  42
  43static const struct smp_operations tango_smp_ops __initconst = {
  44        .smp_boot_secondary     = tango_boot_secondary,
  45#ifdef CONFIG_HOTPLUG_CPU
  46        .cpu_kill               = tango_cpu_kill,
  47        .cpu_die                = tango_cpu_die,
  48#endif
  49};
  50
  51CPU_METHOD_OF_DECLARE(tango4_smp, "sigma,tango4-smp", &tango_smp_ops);
  52