Messages in this thread | | | Date | Thu, 3 Nov 2022 11:21:47 +0000 | From | Sudeep Holla <> | Subject | Re: [PATCH v4 0/11] Introduce a unified API for SCMI Server testing |
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On Fri, Oct 28, 2022 at 07:38:25PM -0700, Florian Fainelli wrote: > Hi Christian, > > On 10/19/2022 1:46 PM, Cristian Marussi wrote: > [snip] > > > In V2 the runtime enable/disable switching capability has been removed > > (for now) since still not deemed to be stable/reliable enough: as a > > consequence when SCMI Raw support is compiled in, the regular SCMI stack > > drivers are now inhibited permanently for that Kernel. > > For our platforms (ARCH_BRCMSTB) we would need to have the ability to start > with the regular SCMI stack to satisfy if nothing else, all clock consumers > otherwise it makes it fairly challenging for us to boot to a prompt as we > purposely turn off all unnecessary peripherals to conserve power. We could > introduce a "full on" mode to remove the clock provider dependency, but I > suspect others on "real" silicon may suffer from the same short comings. >
Fair enough. But if we are doing SCMI firmware testing or conformance via the $subject proposed way, can these drivers survive if the userspace do a random or a torture test changing the clock configurations ? Not sure how to deal with that as the intention here is to do the testing from the user-space and anything can happen. How do we avoid bring the entire system down while doing this testing. Can we unbind all the drivers using scmi on your platform ? I guess no. Let me know.
> Once user-space is reached, I suppose we could find a way to unbind from all > SCMI consumers, and/or ensure that runtime PM is disabled, cpufreq is in a > governor that won't do any active frequency switching etc. > > What do you think?
Yes, Cristian always wanted to support that but I am the one trying to convince him not to unless there is a strong requirement for it. You seem to suggest that you have such a requirement, but that just opens loads of questions and how to we deal with that. Few of them are as stated above, I need to recall all the conversations I had with Cristian around that and why handling it may be bit complex.
-- Regards, Sudeep
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