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    SubjectRe: [PATCH 04/11] ST SPEAr: Added basic header files for SPEAr platform
    On Wed, 10 Mar 2010, Paul Mundt wrote:
    > On Wed, Mar 10, 2010 at 03:41:51PM +0530, Viresh KUMAR wrote:
    > > As you may have seen in spear.h files in mach folders, we have multiple hardware
    > > timers in our design (3 in spear3xx, 4 in spear6xx and each timer have two
    > > independent channels. That doubles the timers count, so it is 6 and 8).
    > > One timer (or two channels) are used by clock event and clock source, but rest of
    > > the timers are still available. So we need some way to export this functionality
    > > of our hardware. It can be considered simply as a driver for GPT.
    > >
    > > What do you say?
    > >
    > This is hardly a unique situation for your platform, this is true for
    > most platforms. There's no reason why clockevents couldn't just be
    > extended and drivers could then just grab unused clockevents and pin them
    > accordingly. Most of the infrastructure is already in place for something
    > like that, without really having to do anything special.
    > Having said that, most drivers have pretty lame reasons for trying to get
    > at fixed timer channels, and most of the time they can easily get by with
    > an hrtimer instead. There's also the issue that you're effectively
    > bypassing nohz by having some timer channel off on the side doing who
    > knows what. You would need a pretty compelling reason for why you are
    > sidestepping all of the existing infrastructure anyways.

    Right, and that's exactly the reason why we did not add the few
    missing bits to make clock events directly usable from drivers.



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