* Tero Kristo <t-kristo@xxxxxx> [141113 23:33]: > On 11/14/2014 01:58 AM, Tony Lindgren wrote: > > The PRCM/clock cleanups that I have under work basically splits the clock > inits under their respective IP blocks; currently everything is registered > under generic PRCM. System control module will be one of the clock providers > (and is going to look like a driver), which will be registering its own > clocks. Yes that's nice. The clock modules in the SCM should probably use the syscon mapping unless there's a clear separate IO area for them. And then use pinctrl for registers that are muxes for external pins unless they are in some dedicated clock register area. > This doesn't change the fact that pinctrl is directly mapping its > own register space atm though, it might be possible to re-route this to use > the generic system control module if need be though. Mapping dedicated IO areas to individual drivers is not a problem. These drivers can eventually be children of a core SCM driver if needed. > I guess its just a political decision which way we want to go, currently we > have lots of system control clocks under the clock data (for > AM33xx,AM43xx,OMAP3), but we can remove these easily if need be. In some > cases it is nicer to have the data in the clock tree though, the drivers > don't need to care if they are touching a clock or a pinctrl entity. Some > people have been converting additional stuff to CCF outside of PRCM, like > Archit did some work to try and get control module clock support for DRA7, > and Tomi has been talking to convert some of the DSS internal clocks to CCF > also. Setting up CCF drivers for SCM makes sense to me. I suggest the following guidelines: 1. If there's a clear separate dedicated IO area in SCM, it can be a driver implementing a Linux generic framework for CCF, regulators, pinctrl, or PHY. 2. For the random control registers, we should use syscon or pinctrl-single to implement Linux generic framwork functions for CCF, regulators, pinctrl or PHY. 3. For resource management, we can have a core SCM driver that takes care of the save and restore of registers and clocking if needed. I believe currently SCM clocks are always enabled though. We can set the drivers in #1 and #2 abobe to be childer of the core SCM driver if we ever need to manage clocks during runtime. Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
