[RFC 2/7] ARM: dts: sun9i: Add CCI-400 device nodes for A80

Chen-Yu Tsai wens at csie.org
Tue May 19 00:12:11 PDT 2015


On Sun, May 17, 2015 at 10:51 PM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> On Thu, May 14, 2015 at 02:10:06PM +0800, Chen-Yu Tsai wrote:
>> The A80 includes an ARM CCI-400 interconnect to support multi-cluster
>> CPU caches.
>>
>> Also add the default clock frequency for the CPUs.
>>
>> Signed-off-by: Chen-Yu Tsai <wens at csie.org>
>> ---
>>  arch/arm/boot/dts/sun9i-a80.dtsi | 46 ++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 46 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/sun9i-a80.dtsi b/arch/arm/boot/dts/sun9i-a80.dtsi
>> index ca272e92b85d..200e712fbf0e 100644
>> --- a/arch/arm/boot/dts/sun9i-a80.dtsi
>> +++ b/arch/arm/boot/dts/sun9i-a80.dtsi
>> @@ -58,48 +58,64 @@
>>               cpu0: cpu at 0 {
>>                       compatible = "arm,cortex-a7";
>>                       device_type = "cpu";
>> +                     cci-control-port = <&cci_control0>;
>> +                     clock-frequency = <12000000>;
>>                       reg = <0x0>;
>>               };
>>
>>               cpu1: cpu at 1 {
>>                       compatible = "arm,cortex-a7";
>>                       device_type = "cpu";
>> +                     cci-control-port = <&cci_control0>;
>> +                     clock-frequency = <12000000>;
>>                       reg = <0x1>;
>>               };
>>
>>               cpu2: cpu at 2 {
>>                       compatible = "arm,cortex-a7";
>>                       device_type = "cpu";
>> +                     cci-control-port = <&cci_control0>;
>> +                     clock-frequency = <12000000>;
>>                       reg = <0x2>;
>>               };
>>
>>               cpu3: cpu at 3 {
>>                       compatible = "arm,cortex-a7";
>>                       device_type = "cpu";
>> +                     cci-control-port = <&cci_control0>;
>> +                     clock-frequency = <12000000>;
>>                       reg = <0x3>;
>>               };
>>
>>               cpu4: cpu at 100 {
>>                       compatible = "arm,cortex-a15";
>>                       device_type = "cpu";
>> +                     cci-control-port = <&cci_control1>;
>> +                     clock-frequency = <9000000>;
>
> Isn't the clock frequency property is supposed to be the maximum
> frequency of that CPU in Linux?
>
> It looks odd that the A15 are clocked at a lower frequency than the
> A7...

You're right. Looking at the FEX file, the A15s can go up to 1.8 GHz.
I'll update the numbers.

ChenYu



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