On Fri, Feb 27, 2015 at 12:49:11PM +0000, John Harrison wrote: > On 25/02/2015 21:31, Daniel Vetter wrote: > >On Wed, Feb 18, 2015 at 02:28:16PM +0000, John Harrison wrote: > >>On 13/02/2015 17:03, Chris Wilson wrote: > >>>On Fri, Feb 13, 2015 at 04:58:24PM +0000, John Harrison wrote: > >>>>On 13/02/2015 12:19, Chris Wilson wrote: > >>>>>On Fri, Feb 13, 2015 at 11:48:56AM +0000, John.C.Harrison@xxxxxxxxx wrote: > >>>>>>From: John Harrison <John.C.Harrison@xxxxxxxxx> > >>>>>> > >>>>>>Updated ironlake_enable_rc6() to do explicit request creation and submission. > >>>>>If you merged the context here with the common context switching code, > >>>>>we don't even need to touch the ring here. > >>>>>-Chris > >>>>> > >>>>It would certainly be preferable to not have any ring commands > >>>>written from deep within the power management code. However, I > >>>>didn't want to change anything I didn't really need to, especially > >>>>in code that I'm not at all sure about. Plus I don't have an > >>>>ironlake to test any significant change on. > >>>I did and tested extensively. > >>>-Chris > >>Do you have a patch that just does the move of this from PM code to context > >>switch code? Something that I can drop into this series would be great. If > >>not, exactly where about in the context switch code should it go? Should it > >>be in the start of day initialisation, in the per context intialisation, > >>every context switch, only the first switch after a resume, ...? > >> > >>Tracing back to where/when this code is currently executed seems to be quite > >>complicated. The _enable_rc6() function is called during ring reset but only > >>for Gen6+ because Ironlake is broken according to the comment. It is also > >>called by a system power management callback but it is unclear when that > >>would occur. Finally, it is also called from the display code in > >>intel_modeset_init_hw(). > >ilk rc6 is disabled by default because it crashes machines hard and > >doesn't seem to be all that useful really. Compared to gen6+ rc6 which has > >a massive impact on idle power consumption, more with each generation. > > > >I've also never heard of anyone managing to make this work reliably. We > >could also just rip the entire code out I think, at least I wouldn't be > >surprised if it has bitrot completely by now. > >-Daniel > > So just remove the ironlake_enable_rc6() function completely? Or keep it as > a stub that just says '/* this has never worked so has been removed */'. Just remove it entirely, together with all the other ironlake rc6 stuff plus functions only called by it. All the ironlake_*_rc6 stuff essentially. ironlake_*_drps is the turbo support, that part needs to stay. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
