diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2013-10-24 19:30:19 (GMT) |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2013-10-25 10:33:21 (GMT) |
| commit | 831ccf79b46e02f31cfd16c66df9d5600f635155 (patch) | |
| tree | 08f653a531e0a81569176f9ed365171dd6cebde9 /arch/arm64/kernel | |
| parent | 9327e2c6bb8cb0131b38a07847cd58c78dc095e9 (diff) | |
| download | linux-831ccf79b46e02f31cfd16c66df9d5600f635155.tar.xz | |
arm64: add PSCI CPU_OFF-based hotplug support
This patch adds support for using PSCI CPU_OFF calls for CPU hotplug.
With this code it is possible to hot unplug CPUs with "psci" as their
boot-method, as long as there's an appropriate cpu_off function id
specified in the psci node.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/psci.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index fb56b61..4f97db3 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -256,11 +256,41 @@ static int cpu_psci_cpu_boot(unsigned int cpu) return err; } +#ifdef CONFIG_HOTPLUG_CPU +static int cpu_psci_cpu_disable(unsigned int cpu) +{ + /* Fail early if we don't have CPU_OFF support */ + if (!psci_ops.cpu_off) + return -EOPNOTSUPP; + return 0; +} + +static void cpu_psci_cpu_die(unsigned int cpu) +{ + int ret; + /* + * There are no known implementations of PSCI actually using the + * power state field, pass a sensible default for now. + */ + struct psci_power_state state = { + .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, + }; + + ret = psci_ops.cpu_off(state); + + pr_crit("psci: unable to power off CPU%u (%d)\n", cpu, ret); +} +#endif + const struct cpu_operations cpu_psci_ops = { .name = "psci", .cpu_init = cpu_psci_cpu_init, .cpu_prepare = cpu_psci_cpu_prepare, .cpu_boot = cpu_psci_cpu_boot, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_disable = cpu_psci_cpu_disable, + .cpu_die = cpu_psci_cpu_die, +#endif }; #endif |