Messages in this thread | | | Subject | Re: [PATCH 1/3] PM: domains: Drop the performance state vote for a device at detach | From | Dmitry Osipenko <> | Date | Thu, 9 Sep 2021 16:48:49 +0300 |
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07.09.2021 13:16, Ulf Hansson пишет: ... >>> Also note that a very similar problem exists, *before* the device gets >>> attached in the first place. More precisely, nothing prevents the >>> performance state from being set to a non-compatible value for an >>> always-on HW/device that hasn't been attached yet. So maybe you need >>> to set the maximum performance state at genpd initializations, then >>> use the ->sync_state() callback to very that all consumers have been >>> attached to the genpd provider, before allowing the state to be >>> changed/lowered? >> >> That is already done by the PD driver. >> >> https://elixir.bootlin.com/linux/latest/source/drivers/soc/tegra/pmc.c#L3790 > > Yes, I already knew that, but forgot it. :-) Thanks for the pointer. > Let me rethink the approach. > > In a way, it kind of sounds like this is a generic problem - so > perhaps we should think of adding a ->withdraw_sync_state() callback > that can be assigned by provider drivers, to get informed when a > consumer driver is getting unbinded.
Not sure, doesn't feel to me that this is necessary for today. A bit too cumbersome for a simple sanity-check, IMO.
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