On 05/05/2020 19:25, Marc Zyngier wrote:
> On Tue, 05 May 2020 17:52:03 +0100,
> Andre Przywara <andre.przywara@xxxxxxx> wrote:
>>
>> The GIC DT binding only allows a certain combination of DT compatible
>> strings, mostly just consisting of one name.
>>
>> Drop the combination of multiple names and go with the
>> "arm,cortex-a15-gic" name for GICv2, as this seems to be the most widely
>> accepted string. "arm,gic-400" would be more correct, but was introduced
>> much later into the kernel's GIC driver.
>>
>> Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
>> ---
>> arch/arm64/boot/dts/arm/foundation-v8-gicv2.dtsi | 2 +-
>> arch/arm64/boot/dts/arm/juno-base.dtsi | 2 +-
>> arch/arm64/boot/dts/arm/rtsm_ve-aemv8a.dts | 2 +-
>> 3 files changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm64/boot/dts/arm/foundation-v8-gicv2.dtsi b/arch/arm64/boot/dts/arm/foundation-v8-gicv2.dtsi
>> index 15fe81738e94..61a1750fcdd6 100644
>> --- a/arch/arm64/boot/dts/arm/foundation-v8-gicv2.dtsi
>> +++ b/arch/arm64/boot/dts/arm/foundation-v8-gicv2.dtsi
>> @@ -6,7 +6,7 @@
>>
>> / {
>> gic: interrupt-controller@2c001000 {
>> - compatible = "arm,cortex-a15-gic", "arm,cortex-a9-gic";
>> + compatible = "arm,cortex-a15-gic";
>> #interrupt-cells = <3>;
>> #address-cells = <2>;
>> interrupt-controller;
>> diff --git a/arch/arm64/boot/dts/arm/juno-base.dtsi b/arch/arm64/boot/dts/arm/juno-base.dtsi
>> index 3feefd61eb76..62392ab1f880 100644
>> --- a/arch/arm64/boot/dts/arm/juno-base.dtsi
>> +++ b/arch/arm64/boot/dts/arm/juno-base.dtsi
>> @@ -69,7 +69,7 @@
>> };
>>
>> gic: interrupt-controller@2c010000 {
>> - compatible = "arm,gic-400", "arm,cortex-a15-gic";
>> + compatible = "arm,cortex-a15-gic";
>
> Why? GIC-400 is definitely the most correct compatible string. I'd
> rather see this compatible being generalised to the models rather than
> only referencing the A15 GIC.
I agree that gic-400 is the far better name, but it was only introduced
in v3.16. So omitting arm,cortex-a15-gic would break any kernels before
that, which I would like to avoid.
It's actually a pity that we are so picky about the compatible listings,
because the existing combination is actually quite nice: we get
compatibility with older DT consumers, but still can say what it
actually is.
I wonder if I should introduce this combination to the GIC DT binding
instead, it seems like there are other users in the tree as well.
What do you think?
Cheers,
Andre
>
>> reg = <0x0 0x2c010000 0 0x1000>,
>> <0x0 0x2c02f000 0 0x2000>,
>> <0x0 0x2c04f000 0 0x2000>,
>> diff --git a/arch/arm64/boot/dts/arm/rtsm_ve-aemv8a.dts b/arch/arm64/boot/dts/arm/rtsm_ve-aemv8a.dts
>> index c5d15cbd8cf6..f86f6451411f 100644
>> --- a/arch/arm64/boot/dts/arm/rtsm_ve-aemv8a.dts
>> +++ b/arch/arm64/boot/dts/arm/rtsm_ve-aemv8a.dts
>> @@ -95,7 +95,7 @@
>> };
>>
>> gic: interrupt-controller@2c001000 {
>> - compatible = "arm,cortex-a15-gic", "arm,cortex-a9-gic";
>> + compatible = "arm,cortex-a15-gic";
>> #interrupt-cells = <3>;
>> #address-cells = <0>;
>> interrupt-controller;
>> --
>> 2.17.1
>>
>>
>
> Thanks,
>
> M.
>
