diff options
Diffstat (limited to 'arch/arm/mach-tango/platsmp.c')
| -rw-r--r-- | arch/arm/mach-tango/platsmp.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/arm/mach-tango/platsmp.c b/arch/arm/mach-tango/platsmp.c index a21f55e00..98c62a4a8 100644 --- a/arch/arm/mach-tango/platsmp.c +++ b/arch/arm/mach-tango/platsmp.c @@ -1,3 +1,4 @@ +#include <linux/delay.h> #include <linux/init.h> #include <linux/smp.h> #include "smc.h" @@ -9,8 +10,42 @@ static int tango_boot_secondary(unsigned int cpu, struct task_struct *idle) return 0; } +#ifdef CONFIG_HOTPLUG_CPU +/* + * cpu_kill() and cpu_die() run concurrently on different cores. + * Firmware will only "kill" a core once it has properly "died". + * Try a few times to kill a core before giving up, and sleep + * between tries to give that core enough time to die. + */ +static int tango_cpu_kill(unsigned int cpu) +{ + int i, err; + + for (i = 0; i < 10; ++i) { + msleep(10); + err = tango_aux_core_kill(cpu); + if (!err) + return true; + } + + return false; +} + +static void tango_cpu_die(unsigned int cpu) +{ + while (tango_aux_core_die(cpu) < 0) + cpu_relax(); + + panic("cpu %d failed to die\n", cpu); +} +#endif + static const struct smp_operations tango_smp_ops __initconst = { .smp_boot_secondary = tango_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_kill = tango_cpu_kill, + .cpu_die = tango_cpu_die, +#endif }; CPU_METHOD_OF_DECLARE(tango4_smp, "sigma,tango4-smp", &tango_smp_ops); |