18.08.2021 19:39, Thierry Reding пишет: >> We don't have a platform device for CaR. I don't see how it's going to >> work. We need to create a platform device for each RPM-capable clock >> because that's how RPM works. The compatible string is required for >> instantiating OF-devices from a node, otherwise we will have to >> re-invent the OF core. > I think we do have a platform device for CAR. It's just not bound > against by the driver because these clock drivers are "special". But > from other parts of the series you're already trying to fix that, at > least partially. > > But it doesn't seem right to create a platform device for each RPM- > capable clock. Why do they need to be devices? They aren't, so why > pretend? Is it that some API that we want to use here requires the > struct device? The "device" representation is internal to the kernel. It's okay to me to have PLLs represented by a device, it's a distinct h/w by itself. CCF supports managing of clock's RPM and it requires to have clock to be backed by a device. That's what we are using here. Please see https://elixir.bootlin.com/linux/v5.14-rc6/source/drivers/clk/clk.c#L109 >>> Also, I don't think the tegra- prefix is necessary here. The parent node >>> is already identified as Tegra via the compatible string. >>> >>> In the case of CAR, I'd imagine something like: >>> >>> clocks { >>> sclk { >>> operating-points-v2 = <&opp_table>; >>> power-domains = <&domain>; >>> }; >>> }; >>> >>> Now you've only got the bare minimum in here that you actually add. All >>> the other data that you used to have is simply derived from the parent. >> 'clocks' is already a generic keyword in DT. It's probably not okay to >> redefine it. > "clocks" is not a generic keyword. It's the name of a property and given > that we're talking about the clock provider here, it doesn't need a > clocks property of its own, so it should be fine to use that for the > node. I'm curious what Rob thinks about it. Rob, does this sound okay to you?