On 21 November 2014 22:45, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Friday 21 November 2014 22:06:51 Jassi Brar wrote: >> >> Only MB86S70_CRG11_UNGPRT is marked to mean one special (non-maskable) >> >> port on the controller, which the clock driver does make use of. >> > >> > Is this the actual port number that is known to be non-maskable? >> > >> Yes the clock comes out of the controller and is also the parent of >> other 8 independently maskable clock ports of the domain. > > I'm getting confused by the terminology here. Is MB86S70_CRG11_ALW > a port or a controller? > Sorry, bad symbols. ALW..DPHY are controllers. UNGPRT is the ninth parent clock (port) of a domain that can't be masked. FYKI, there are 6 instances, of some CRG11 clock controller, under control of the remote f/w. The Mailbox protocol between remote f/w and Linux assigned indices [0-5] to these controllers. >> The firmware on remote master, lets say, don't wanna be bothered by >> the clock topology. Even for set-rate the onus is on Linux to request >> only appropriate rates at appropriate times so that other devices are >> not messed up. > > Is there any code to validate that, or does Linux just treat all > clocks transparently? > The remote does not expose the clock topology and only accepts requests on port-basis. The remote f/w is supposed to keep track of which ports are used by Linux and then work out inter-dependencies upon receiving a request from Linux. So for Linux there are N independent 'root' clocks, ops on which may or may not succeed at any given time. thanks jassi -- 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
