[PATCH] ARM: rockchip: Add cpu hotplug support for RK3XXX SoCs
Romain Perier
romain.perier at gmail.com
Thu Jul 17 10:11:50 PDT 2014
Adds ability to shutdown all CPUs except the first one
(since it might be special for a lot of platforms).
It is now possible to use kexec which requires such a feature.
Signed-off-by: Romain Perier <romain.perier at gmail.com>
---
arch/arm/mach-rockchip/platsmp.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
index 910835d..7c1299a 100644
--- a/arch/arm/mach-rockchip/platsmp.c
+++ b/arch/arm/mach-rockchip/platsmp.c
@@ -21,6 +21,7 @@
#include <linux/of_address.h>
#include <asm/cacheflush.h>
+#include <asm/cp15.h>
#include <asm/smp_scu.h>
#include <asm/smp_plat.h>
#include <asm/mach/map.h>
@@ -178,8 +179,38 @@ static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus)
pmu_set_power_domain(0 + i, false);
}
+#ifdef CONFIG_HOTPLUG_CPU
+static DECLARE_COMPLETION(cpu_died);
+
+static int rockchip_cpu_kill(unsigned int cpu)
+{
+ if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(1000))) {
+ pr_err("CPU%d: didn't die correctly\n", cpu);
+ return 0;
+ }
+ pmu_set_power_domain(0 + cpu, false);
+ return 1;
+}
+
+
+static void rockchip_cpu_die(unsigned int cpu)
+{
+ complete(&cpu_died);
+ flush_cache_louis();
+
+ v7_exit_coherency_flush(louis);
+
+ while(1)
+ cpu_do_idle();
+}
+#endif
+
static struct smp_operations rockchip_smp_ops __initdata = {
.smp_prepare_cpus = rockchip_smp_prepare_cpus,
.smp_boot_secondary = rockchip_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_kill = rockchip_cpu_kill,
+ .cpu_die = rockchip_cpu_die,
+#endif
};
CPU_METHOD_OF_DECLARE(rk3066_smp, "rockchip,rk3066-smp", &rockchip_smp_ops);
--
1.9.1
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