On Thu, Feb 01, 2018 at 05:43:56PM +0000, Andy Lutomirski wrote: > On Thu, Feb 1, 2018 at 9:40 AM, Andy Lutomirski <luto@xxxxxxxxxx> wrote: > > Hi- > > > > As requested in your blog post, I tested PSR. I see something like > > 2.69W with PSR off and 2.17W with PSR on. Screen blanking, > > suspend/resume, and the contents of the screen all seem okay. This is > > a Dell XPS 13 9350, i.e.: > > > > System Information > > Manufacturer: Dell Inc. > > Product Name: XPS 13 9350 > > > > EDID is attached. > > > > *However*, I do see one unfortunate side effect of turning on PSR. It > > seems that, when I move my cursor a little bit after a few seconds of > > doing nothing, there seems to be a little bit of lag, as if either a > > few frames are dropped at the beginning of the motion or maybe the > > entire motion is delayed a bit. I don't notice a similar delay when > > typing, so I'm wondering if maybe there's a minor driver bug in which > > the driver doesn't kick the panel out of PSR quite as quickly when the > > cursor is updated as it does when the framebuffer is updated. > > > > I'm also getting occasional messages like: > > [ 2675.574486] [drm:intel_pipe_update_start [i915]] *ERROR* Potential > atomic update failure on pipe A > > with PSR on. But there is nowhere near one of these messages per tiny > lag incident. That's indeed strange. I believe that should also be part of PSR + DMC, so could you check if you see this with psr enabled + dc state disabled? I wonder if those I915_READ_FW are not waking DMC hence reading 0 in some registers. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
