Messages in this thread Patch in this message | | | From | Pramod Kumar <> | Subject | [PATCH RFC 1/1] arm64: Use PSCI calls for CPU stop when hotplug is supported | Date | Fri, 18 Jan 2019 11:16:20 +0530 |
| |
If CPU hotplug is supported, ipi_cpu_stop should use PSCI cpudie call to stop the CPU. This call ensures L1/L2 cache flush, CPUs cache-cohenrecy setting w.r.to interconnect.
Apart from this, this gives control to f/w to reduce power consumption by take appropriate decesion on power rails for plugging-out core.
Signed-off-by: Pramod Kumar <pramod.kumar@broadcom.com> Reviewed-by: Ray Jui <ray.jui@broadcom.com> Reviewed-by: Scott Branden <scott.branden@broadcom.com> --- arch/arm64/kernel/smp.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 1598d6f..360e52b 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -822,8 +822,13 @@ static void ipi_cpu_stop(unsigned int cpu) local_daif_mask(); sdei_mask_local_cpu(); +#ifdef CONFIG_HOTPLUG_CPU + if (cpu_ops[cpu]->cpu_die) + cpu_ops[cpu]->cpu_die(cpu); +#else while (1) cpu_relax(); +#endif } #ifdef CONFIG_KEXEC_CORE -- 1.9.1
| |