On 15/11/2022 15:44, AngeloGioacchino Del Regno wrote: >>>> Please check and re-submit. >>>> >>> >>> I'm unsure about what I should do about this one. >>> This is a power-controller, but does *not* need any #power-domain-cells, as it is >>> standalone and doesn't require being attached to anything. >> >> power-domain-cells are for power domain providers, not consumers. The >> generic binding expect that nodes called power-controller are exactly >> like that. >> >> Solutions could be: >> 1. Rename the node to something else. I cannot deduct the type of the >> device based on description. What is "sequence ID" and how is it even >> closely related to power control? > > This uC is mainly controlling DCVS, automagically plays with voltages for > each ramp up/down step and from what I understand also decides to shut down > or bring up *power* to "certain clocks" before ungating (CPU related, mainly > big cluster). > This also interacts with LMH - setting the LMH part makes it possible to > later use CPR (otherwise CPR errors out internally and won't start, as it > requires this controller, SAW and LMH to be set up in order to work). > > What I've seen is that without it I can't bring up the big cluster at all, > not even at minimum frequency, as the HF2PLL (a clock source for that cluster) > will not power up. > All it takes is to initialize these params and start the controller, then > everything goes as it should. > > If you're wondering why my explanation may not be particularly satisfying, > that's because downstream contains practically no information about this > one, apart from a bunch of lines of code and because this controller is > just a big black box. > >> >> 2. Narrow the node name in power-domain.yaml which would require changes >> in multiple DTS and bindings. >> >> 3. Do not require power-domain-cells for power-controllers, only for >> power-domains. >> > > Solutions 2 and 3... well, I don't think that this would be really feasible > as I envision this being the one and only driver that will ever require > that kind of thing. > Also, this programming was later moved to bootloaders and the only SoCs that > will ever require this are MSM8956/76, MSM8953 and.. I think MSM8952 as well, > but nothing more. > > Even if I can imagine the answer, I'm still tempted to ask: can we eventually > just name it ramp-controller@xxxx or qcom-rc@xxxx or something "special" like > that to overcome to this binding issue? So maybe "cpu-power-controller"? This should already help for this warning. Best regards, Krzysztof
