[PATCH] keystone: psci: adds cpu_die implementation
mark.rutland at arm.com
Thu Jun 25 09:13:08 PDT 2015
On Thu, Jun 25, 2015 at 05:01:36PM +0100, Vitaly Andrianov wrote:
> On 06/25/2015 10:59 AM, santosh shilimkar wrote:
> > On 6/25/2015 7:45 AM, Mark Rutland wrote:
> >> Hi,
> >> On Thu, Jun 25, 2015 at 03:02:50PM +0100, Vitaly Andrianov wrote:
> >>> This commit add cpu_die implementation using psci api
> >> I don't understand. If you have a PSCI implementation, it should be
> >> sufficient to have a PSCI node (and enable-method) in your DT, and the
> >> generic code will be used. Nothing should be required in your board
> >> code.
> >> You should also use CPU_ON to bring secondaries online rather than
> >> mixing up PSCI and platform-specific mechanisms.
> > Good point about CPU_ON. We need that as well.
> Does it mean that keystone_defconfig must always have CONFIG_HOTPLUG_CPU
> and CONFIG_ARM_PSCI enabled?
You need CONFIG_ARM_PSCI for PSCI CPU_ON. Without CONFIG_HOTPLUG_CPU,
you'll get PSCI CPU_ON but not PSCI CPU_OFF.
> What is if someone doesn't want to have HOTPLUG_CPU?
Then you don't get PSCI CPU_OFF, but can still have PSCI CPU_ON.
Only the portions of the PSCI code required for turning CPUs off are
dependent on HOTPLUG_CPU.
> How he can boot secondary CPU w/o platform-specific mechanizm?
By using PSCI CPU_ON.
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