[PATCH 5/7] ARM: dts: imx6ul: add ARM architected timer
Stefan Agner
stefan at agner.ch
Tue Jan 9 05:18:02 PST 2018
On 2018-01-09 10:34, Dong Aisheng wrote:
> Hi Stefan,
>
> On Tue, Jan 02, 2018 at 05:42:21PM +0100, Stefan Agner wrote:
>> Add per-core ARM architected timer. Unfortunately bootloaders (U-Boot)
>> currently do not make the necessary initialization. Also specifing the
>> clock manually using the clock-frequency property seems not to help.
>> Therefor leave the timer disabled by default for now.
>>
>> Signed-off-by: Stefan Agner <stefan at agner.ch>
>
> Any special purpose to use arch timer?
>
It is the better option. It supports virtualization and allows direct
user space access, e.g. as used in OpenSSL through _armv7_tick.
--
Stefan
>> ---
>> arch/arm/boot/dts/imx6ul.dtsi | 10 ++++++++++
>> 1 file changed, 10 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/imx6ul.dtsi b/arch/arm/boot/dts/imx6ul.dtsi
>> index 993fbdbdd506..4d76923e8f44 100644
>> --- a/arch/arm/boot/dts/imx6ul.dtsi
>> +++ b/arch/arm/boot/dts/imx6ul.dtsi
>> @@ -110,6 +110,16 @@
>> <0x00a06000 0x2000>;
>> };
>>
>> + timer {
>> + compatible = "arm,armv7-timer";
>> + interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
>> + <GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
>> + <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
>> + <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>;
>> + interrupt-parent = <&intc>;
>> + status = "disabled";
>> + };
>> +
>> ckil: clock-cli {
>> compatible = "fixed-clock";
>> #clock-cells = <0>;
>> --
>> 2.15.1
>>
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