Re: [PATCH v4 09/13] dt-bindings: riscv: Add T-Head PMU extension description

[Inochi Amaoto]

>
>Hi Guo Ren,
>
>On Thu, Nov 23, 2023 at 05:14:30AM +0800, Guo Ren wrote:
>> On Wed, Nov 22, 2023 at 8:17 PM Yu Chien Peter Lin
>> <peterlin@xxxxxxxxxxxxx> wrote:
>>>
>>> Document the ISA string for T-Head performance monitor extension
>>> which provides counter overflow interrupt mechanism.
>>>
>>> Signed-off-by: Yu Chien Peter Lin <peterlin@xxxxxxxxxxxxx>
>>> ---
>>> Changes v2 -> v3:
>>>   - New patch
>>> Changes v3 -> v4:
>>>   - No change
>>> ---
>>>  Documentation/devicetree/bindings/riscv/extensions.yaml | 6 ++++++
>>>  1 file changed, 6 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
>>> index c91ab0e46648..694efaea8fce 100644
>>> --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
>>> +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
>>> @@ -258,5 +258,11 @@ properties:
>>>              in commit 2e5236 ("Ztso is now ratified.") of the
>>>              riscv-isa-manual.
>>>
>>> +        - const: xtheadpmu
>>> +          description:
>>> +            The T-Head performance monitor extension for counter overflow. For more
>>> +            details, see the chapter 12 in the Xuantie C906 user manual.
>>> +            https://github.com/T-head-Semi/openc906/tree/main/doc
>>> +
>>>  additionalProperties: true
>>>  ...
>>> --
>>> 2.34.1
>>>
>> Reviewed-by: Guo Ren <guoren@xxxxxxxxxx>
>
>Thanks for the review.
>Would you share document about T-Head PMU?
>

Hi, Peter Lin:

You can use the following two document to get all events:
https://github.com/T-head-Semi/openc906/tree/main/doc
https://github.com/T-head-Semi/openc910/tree/main/doc

There are also some RTL code can describe these events:
https://github.com/T-head-Semi/openc910/blob/e0c4ad8ec7f8c70f649d826ebd6c949086453272/C910_RTL_FACTORY/gen_rtl/pmu/rtl/ct_hpcp_top.v#L1123
https://github.com/T-head-Semi/openc906/blob/af5614d72de7e5a4b8609c427d2e20af1deb21c4/C906_RTL_FACTORY/gen_rtl/pmu/rtl/aq_hpcp_top.v#L543

The perf events json can also be used as document, this is already
applied (with more detailed explanation):
https://lore.kernel.org/all/IA1PR20MB495325FCF603BAA841E29281BBBAA@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/

Best regards,
Inochi