On 11/12/2012 02:36 PM, John Stultz wrote: > On 11/12/2012 12:51 PM, Stephen Warren wrote: >> Currently, whenever CONFIG_ARCH_USES_GETTIMEOFFSET is enabled, each >> arch core provides a single implementation of arch_gettimeoffset(). In >> many cases, different sub-architectures, different machines, or >> different timer providers exist, and so the arch ends up implementing >> arch_gettimeoffset() as a call-through-pointer anyway. Examples are >> ARM, Cris, M68K, and it's arguable that the remaining architectures, >> M32R and Blackfin, should be doing this anyway. >> >> Modify arch_gettimeoffset so that it itself is a function pointer, which >> the arch initializes. This will allow later changes to move the >> initialization of this function into individual machine support or timer >> drivers. This is particularly useful for code in drivers/clocksource >> which should rely on an arch-independant mechanism to register their >> implementation of arch_gettimeoffset(). ... > One last thing to watch out for: If you're trying to build a kernel that > mixes clocksource support with get_arch_timeoffset, you'll need to > rework the #ifdef in update_wall_time(), since we currently assume with > get_arch_timeoffset() that you're using tick + interpolation, so every > call to update_wall_time() only moves time forward by one jiffy. OK. I don't have any immediate plans to do that, although I wouldn't be surprised if we (the ARM community in general) end up wanting to do that at some point. It all depends on which ARM sub-architectures end up getting converted to the multi-platform zImage support I guess. > Otherwise, thanks for the name tweak. Going through the arm-soc tree is > fine with me. > > Acked-by: John Stultz <johnstul@xxxxxxxxxx> Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
