[PATCH 0/3] lib: sbi: fix PMU SSE event handling

[Clément Léger]

On 09/12/2024 09:36, Clément Léger wrote:
> 
> 
> On 06/12/2024 23:25, Atish Patra wrote:
>> On Fri, Dec 6, 2024 at 1:00 PM Clément Léger <cleger at rivosinc.com> wrote:
>>>
>>> While reworking the Linux SSE support, it appears that the PMU event
>>> should not be available if the SSCOFPMF extension is not available since
>>> there would be no IRQ. The specification isn't really clear on that point
>>> so this is more like a RFC to check that. Ideally, the sse register call
>>
>> Can you send a patch for SBI spec ? I think we can call it a local PMU
>> overflow event
>> rather than a PMU.
> 
> Yes sure, that makes more sense.  I'll also modify the possible return
> value for register to add NOT_SUPPORTED in case some dependencies are
> missing

While thinking about it, should we actually return ERR_INVALID_PARAM or
add a new ERR_NOT_SUPPORTED if the event is not supported due to missing
dependencies ? It seems like it is different but I'm not sure it adds
any valuable information (ie, the caller is not going to do anything
special about it)

Clément

> 
> Thanks,
> 
> Clément
> 
>>
>> We can add a note about the Sscofpmf dependency as well.
>>
>>> should allow to refuse registering an event if the dependencies are not
>>> satisfied but does not allow this yet.
>>>
>>> Clément Léger (3):
>>>   lib: sbi: sse: Return a value from the register callback
>>>   lib: sbi: sse: Disable injection if callbacks are set
>>>   lib: sbi: pmu: Set a SSE register_cb() for event availability
>>>
>>>  include/sbi/sbi_sse.h |  2 +-
>>>  lib/sbi/sbi_pmu.c     | 11 +++++++++++
>>>  lib/sbi/sbi_sse.c     | 19 +++++++++++++++++--
>>>  3 files changed, 29 insertions(+), 3 deletions(-)
>>>
>>> --
>>> 2.45.2
>>>
>>>
>>> --
>>> opensbi mailing list
>>> opensbi at lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/opensbi
>>
>>
>>
>