summaryrefslogtreecommitdiff
path: root/arch/arm/mach-tango/platsmp.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-tango/platsmp.c')
-rw-r--r--arch/arm/mach-tango/platsmp.c35
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);