On 12/19/2025 5:10 PM, Alvin Che-Chia Chang(張哲嘉) wrote:
> Hi Chao,
>
>> -----Original Message-----
>> From: Chao Liu <[email protected]>
>> Sent: Friday, December 19, 2025 4:09 PM
>> To: [email protected]
>> Cc: [email protected]; Alvin Che-Chia Chang(張哲嘉)
>> <[email protected]>; [email protected];
>> [email protected]; [email protected];
>> [email protected]; [email protected];
>> [email protected]
>> Subject: Re: [PATCH v3 0/2] RISC-V: Initial support versioning of debug
>> specification
>>
>> [EXTERNAL MAIL]
>>
>> On Mon, 1 Dec 2025 09:42:53 +0800, Alvin Chang via wrote:
>>> This series try to support versioning of debug specification. The
>>> early debug implementation supports debug specification v0.13, and
>>> later new trigger types were added which are defined in debug
>>> specification v1.0 version. To support both v0.13 and v1.0, we add
>>> 'debug-1.0' as CPU property to let user choose debug specification
>>> v1.0 by specifying "debug-1.0=true". The default version is still v0.13 if
>> 'debug-1.0' is not provided and set.
>>>
>>> For example, to enable debug specification v1.0 on max CPU:
>>> * -cpu max,debug-1.0=true
>>>
>>> Changes since v2:
>>> * Improve commit message and fix typo
>>> * Apply "Reviewed-by" tags
>>>
>>> Changes since v1:
>>> * Apply suggestions from Daniel. Using boolean property instead of string.
>>
>> This is great work! Thanks to Alvin Chang for refining the sdext. It seems we
>> are one step closer to merging rvsp-ref into the mainline.
>
> Thank you, Chao.
> Please note that this series doesn't implement Sdext infrastructure.
> We have some patches for Sdtrig based on Debug spec v1.0 and we want to
> upstream those patches.
> We ever submitted the patches, but unfortunately the patches were blocked.
> The maintainer told me that QEMU should support both v0.13 and v1.0 for
> backward compatibility, rather than eliminating v0.13.
> That why I submitted this series, trying to resolve the version issue.
>
>
> Sincerely,
> Alvin Chang
>
>
Oh, thank you for your clarification. I also noticed this when reviewing the
main patch series — it was my misunderstanding. Still, thank you for your
contribution!
I have done some development work on Sdext before, but I noticed that
implementations of the DM module vary among different vendors. In addition, how
to achieve compatibility with gdbstub is also a challenge. I will send out the
RFC patches at an appropriate time in the future.
Thanks,
Chao
