On Jun 22, 2011, at 6:36 PM, Alexander Motin wrote: > Marcel Moolenaar wrote: >> On Jun 22, 2011, at 5:30 PM, Alexander Motin wrote: >>> Marcel Moolenaar wrote: >>>> On Jun 22, 2011, at 4:24 PM, Jung-uk Kim wrote: >>>>> I just realized kern_clocksource.c was excluded for arm and ia64. >>>>> Here is updated patch. Please ignore the previous one. >>>> Any reason why we're not adding kern_clocksource.c for them? >>> Their event timers code still waits for refactoring. I have neither >>> documentation nor hardware for them. Help would be appreciated. >> >> Can you give me a pointer to a document orpage that describes >> what is being refactored, why and how? > > In short, timer management code was unified and formalized. Instead of > direct programming periodic timers from MD code and calling hard-/ > stat-/ profclock() from there, timer hardware should be exposed to the > MI kernel using sys/timeet.h API to allow kern_clocksource.c manage it. > Last require calling its cpu_initclocks_bsp() and cpu_initclocks_ap() > callbacks from MD initialization code, and cpu_idleclock() and > cpu_activeclock() from MD cpu_idle(). > > Here is some references: > man 4 eventtimers > http://wiki.freebsd.org/201010DevSummit?action=AttachFile&do=view&target=timers.pdf > http://svnweb.freebsd.org/base?view=revision&revision=209371 > http://svnweb.freebsd.org/base?view=revision&revision=212541 > > All architectures except ia64 and non-Marvell arm are already done, so > you may took any of them as reference. Ask me if you have any questions.
Can you give a quick outline of how all the various clock related initializations and support code relate, interact or even conflict? It's getting rather convoluted and want to make sure I get the ordering and timing right. Also: The ITC on ia64 is a per-CPU, one short and periodic timer that has a fixed frequency. Though the architecture does not guarantee that counters are synchronized, nor that all CPUs in a system run at the same frequency which means that the ITCs may not all run at the same frequency. Does the et code work with that or do I need to impose a restriction on what hardware configurations to support and/or revert to having the ITC be a global timer and run only on the BSP? Thanks, -- Marcel Moolenaar mar...@xcllnt.net _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
