Hey, Op 14-07-12 00:56, Maarten Maathuis schreef: > On Fri, Jul 13, 2012 at 11:35 PM, Maarten Lankhorst > <m.b.lankhorst@xxxxxxxxx> wrote: >> A way to trigger an irq will be needed for optimus support since >> cpu-waiting isn't always viable there. This could also be nice for >> power saving on since cpu would no longer have to spin, and >> performance might improve slightly on cpu-limited workloads. >> >> Some way to quantify these effects would be nice, even if the >> end result would be 'no performance regression'. An earlier >> version always emitted an interrupt, resulting in glxgears going >> from 8k fps to 7k. However this is no longer the case, as I'm >> using the kernel submission channel for generating irqs as >> needed now. >> >> On nv84 I'm using NOTIFY_INTR, but that might have been >> removed on fermi, so instead I'm using invalid command >> 0x0058 now as a way to signal completion. > Out of curiosity, isn't this like a handcoded version of software > methods? If so, why handcoded? Or are software methods not supported > on NVC0? > I don't think there is a software engine, and if you look at the code only the kernel hardware channel will be allowed to raise a wake-up interrupt. On normal channels you'll get a invalid command in dmesg. On nv84 the interrupt will be eaten unless it originated from the kernel hw channel in which case things will be woken up, since it's a valid fifo command there. Either nvc0 and later dropped the support or I wasn't able to activate it during testing. ~Maarten _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
