Re: [PATCH] coresight: docs: Remove target sink from examples

[James Clark <james.clark@linaro.org>]

On 11/12/2024 6:01 pm, Steve Clevenger wrote:
> 
> Hi James,
> 
> I thought I'd mention this issue with multicore self-hosted trace. The
> perf command line syntax does not allow a sink "type" to be specified
> (e.g. @tmc_etf or @tmc_etr). For multicore, it doesn't make sense to
> specify a processor mapped sink as would be the case for single core
> trace. A sink "type" should be allowed to avoid the auto select default.
> In our case, the default is the ETF sink.
> 
> Thanks,
> Steve C.
> 

I'm sure it would be possible to add support for this, but I'm wondering 
if the real issue is that the default selection logic is wrong? Are you 
saying the default you get is ETF but you want ETR? And there is both 
for each ETM? The default selection logic isn't easy to summarize but it 
should prefer ETR (sysmem) over ETF (link sink), see coresight_find_sink().

It's probably better to fix that rather than add a new sink selection 
feature. Maybe if you shared a diagram of your coresight architecture it 
would help.

Thanks
James