Re: [PATCH 3/3] dt-bindings: riscv: sifive: Add SiFive Private L2 cache controller

[Krzysztof Kozlowski]

On 26/06/2023 05:26, Eric Lin wrote:
> Hi Krzysztof,
> 
> On Fri, Jun 16, 2023 at 6:45 PM Krzysztof Kozlowski
> <krzysztof.kozlowski@xxxxxxxxxx> wrote:
>>
>> On 16/06/2023 08:32, Eric Lin wrote:
>>> This add YAML DT binding documentation for SiFive Private L2
>>> cache controller
>>>
>>> Signed-off-by: Eric Lin <eric.lin@xxxxxxxxxx>
>>> Reviewed-by: Zong Li <zong.li@xxxxxxxxxx>
>>> Reviewed-by: Nick Hu <nick.hu@xxxxxxxxxx>
>>> ---
>>>  .../bindings/riscv/sifive,pL2Cache0.yaml      | 81 +++++++++++++++++++
>>>  1 file changed, 81 insertions(+)
>>>  create mode 100644 Documentation/devicetree/bindings/riscv/sifive,pL2Cache0.yaml
>>>
>>> diff --git a/Documentation/devicetree/bindings/riscv/sifive,pL2Cache0.yaml b/Documentation/devicetree/bindings/riscv/sifive,pL2Cache0.yaml
>>> new file mode 100644
>>> index 000000000000..b5d8d4a39dde
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/riscv/sifive,pL2Cache0.yaml
>>> @@ -0,0 +1,81 @@
>>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>>> +# Copyright (C) 2023 SiFive, Inc.
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/riscv/sifive,pL2Cache0.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: SiFive Private L2 Cache Controller
>>> +
>>> +maintainers:
>>> +  - Greentime Hu  <greentime.hu@xxxxxxxxxx>
>>> +  - Eric Lin      <eric.lin@xxxxxxxxxx>
>>> +
>>> +description:
>>> +  The SiFive Private L2 Cache Controller is per hart and communicates with both the upstream
>>> +  L1 caches and downstream L3 cache or memory, enabling a high-performance cache subsystem.
>>> +  All the properties in ePAPR/DeviceTree specification applies for this platform.
>>
>> Drop the last sentence. Why specification would not apply?
>>
> OK, I'll drop it in v2.
> 
>>> +
>>> +allOf:
>>> +  - $ref: /schemas/cache-controller.yaml#
>>> +
>>> +select:
>>> +  properties:
>>> +    compatible:
>>> +      contains:
>>> +        enum:
>>> +          - sifive,pL2Cache0
>>> +          - sifive,pL2Cache
>>> +
>>> +  required:
>>> +    - compatible
>>> +
>>> +properties:
>>> +  compatible:
>>> +    items:
>>
>>
>> You have only one item, so no need for items... unless you just missed
>> proper fallback.
> 
> OK, I'll fix it in v2.
> 
>>
>>> +      - enum:
>>> +          - sifive,pL2Cache0
>>> +          - sifive,pL2Cache1
>>
>> What is "0" and "1" here? What do these compatibles represent? Why they
>> do not have any SoC related part?
> 
> The pL2Cache1 has minor changes in hardware, but it can use the same
> pl2 cache driver.

Then why aren't they compatible?

> May I ask, what do you mean about the SoC-related part? Thanks.

This is part of a SoC, right? We expect SoC blocks to have compatible
based on the SoC.



Best regards,
Krzysztof