[PATCH] arm64: dts: Add PSCI function IDs for cpu-{on,off} on exynos7

Alim Akhtar alim.akhtar at samsung.com
Tue Jan 19 18:52:41 PST 2016


Hi Mark,

On 01/19/2016 04:02 PM, Mark Rutland wrote:
> On Tue, Jan 19, 2016 at 03:51:24PM +0530, Alim Akhtar wrote:
>> This patch adds cpu-{on,off} function IDs as per PSCI specification,
>> with this we can boot multiple CPUs and can use cpu hotplug on
>> exynos7 platform.
>>
>> Signed-off-by: Alim Akhtar <alim.akhtar at samsung.com>
>> ---
>>   arch/arm64/boot/dts/exynos/exynos7.dtsi |    2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/exynos/exynos7.dtsi b/arch/arm64/boot/dts/exynos/exynos7.dtsi
>> index f9c5a549c2c0..1a2bb3b453e5 100644
>> --- a/arch/arm64/boot/dts/exynos/exynos7.dtsi
>> +++ b/arch/arm64/boot/dts/exynos/exynos7.dtsi
>> @@ -65,6 +65,8 @@
>>   	psci {
>>   		compatible = "arm,psci-0.2";
>>   		method = "smc";
>> +		cpu_on = <0xC4000003>;
>> +		cpu_off = <0x84000002>;
>>   	};
>
> There is no need for this patch.
>
> The "arm,psci-0.2" compatible string implicitly tells the kernel that
> the full set of mandatory PSCI 0.2 functions are present, with the IDs
> mandated by PSCI 0.2. That includes CPU_ON and CPU_OFF amongst others.
>
> The only reason to provide IDs is to function on kernels without PSCI
> 0.2 support. Given the compatible string hasn't been updated for that,
> this is insufficient for that case.
>
Ah, right, this patch is not required for psci,0.2, thanks for 
clarification.
sorry for the noise.

> Thanks,
> Mark.
>
>



More information about the linux-arm-kernel mailing list