Re: [PATCH V5 3/6] firmware: arm_scmi: Report duplicate opps as firmware bugs

[Sibi Sankar <quic_sibis@quicinc.com>]

On 11/1/24 19:39, Johan Hovold wrote:
> On Wed, Oct 30, 2024 at 06:25:09PM +0530, Sibi Sankar wrote:
>> Duplicate opps reported by buggy SCP firmware currently show up
>> as warnings even though the only functional impact is that the
>> level/index remain inaccessible. Make it less scary for the end
>> user by using dev_info instead, along with FW_BUG tag.
>>
>> Suggested-by: Johan Hovold <johan+linaro@kernel.org>
>> Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
>> ---
>>   drivers/firmware/arm_scmi/perf.c | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
>> index 32f9a9acd3e9..c7e5a34b254b 100644
>> --- a/drivers/firmware/arm_scmi/perf.c
>> +++ b/drivers/firmware/arm_scmi/perf.c
>> @@ -387,7 +387,7 @@ process_response_opp(struct device *dev, struct perf_dom_info *dom,
>>   
>>   	ret = xa_insert(&dom->opps_by_lvl, opp->perf, opp, GFP_KERNEL);
>>   	if (ret) {
>> -		dev_warn(dev, "Failed to add opps_by_lvl at %d for %s - ret:%d\n",
>> +		dev_info(dev, FW_BUG "Failed to add opps_by_lvl at %d for %s - ret:%d\n",
>>   			 opp->perf, dom->info.name, ret);
> 
> I was hoping you could make the error message a bit more informative as
> well, for example, by saying that a duplicate opp level was ignored:
> 
> 	arm-scmi arm-scmi.0.auto: [Firmware Bug]: Ignoring duplicate OPP 3417600 for NCC

I did think about doing something similar but xa_insert can fail
with both -EXIST (duplicate) and -ENOMEM, so the we can't really
use term duplicate when insert fails. I can add the perf level
though to the message though.

-Sibi

> 
> or similar (e.g. as the current message looks like an error, with errno
> and all, that indeed warrants warning level).
> 
> Perhaps with such a message you could even keep the warning level to
> make it stand out more (if that's desirable) without the risk of scaring
> users.
> 
> Johan