On 25 June 2015 at 13:14, Pavel Fedin <p.fe...@samsung.com> wrote: >> If we want to support "KVM but without in-kernel irqchip" I would >> really prefer that we did it this way, by implementing an ABI for >> letting the kernel tell us about the generic timer interrupts > > Yes, but: > 1. This would work only for newer kernels. > 2. This little patch allows to work on older kernels, at least somehow.
I don't think "needs a newer kernel" is a particularly serious restriction here. Also some boards have no fallback timer device at all (notably "virt", so generic-timer *has* to work. >> IIRC chazy had a hacked-together patch for that at some point. > > Who is it? Where can i find it? I was misremembering. That's Christoffer Dall, and in fact he didn't write any code, he just suggested that it was possible. >> Is hardware with no working VGIC really prevalent enough that >> it's worth adding support? Presumably the performance isn't going >> to be very good... > > At least RaspberryPi 2, as far as i know. Also i am testing on some > Samsung proprietary HW which has the same problem. I hope you have fed back to the h/w designers that they need to fix this for the next revision :-) thanks -- PMM
