[RFC] clocktree representation in the devicetree
From: arnd@arndb.de (Arnd Bergmann)
Date: 2011-10-17 15:02:05
Also in:
linux-devicetree
From: arnd@arndb.de (Arnd Bergmann)
Date: 2011-10-17 15:02:05
Also in:
linux-devicetree
On Monday 17 October 2011, Sascha Hauer wrote:
The following is an attempt to represent the clocktree of a i.MX53 in the devicetree. I created this to see how it would look like and to start a discussion whether we want to move in this direction or not.
Very good, thanks for getting this started!
Some things to consider: - It seems to be very flexible. A board can customize the clock tree by just adding some clk-parent=<phandle> properties to the muxers. - clocks can easily be associated with devices. but: - The following example registers 127 new platform devices and it's not even complete. This adds significant overhead to initialization.
I don't understand enough about the clock trees to understand if the dts representation is good, but it I don't see a reason to represent it as lots of platform devices in linux. We can have lots of device_nodes in the device tree that are not a platform_device but we can still access them through the of_*() functions. Ideally, we would encapsulate all the clock tree parsing in the clk subsystem and provide high-level interfaces to clkdev drivers from there. Arnd