On Fri, Jul 15, 2016 at 12:31 PM, Ilia Mirkin <imirkin@xxxxxxxxxxxx> wrote: > On Fri, Jul 15, 2016 at 12:27 PM, Alex Deucher <alexdeucher@xxxxxxxxx> wrote: >> On Fri, Jul 15, 2016 at 12:10 PM, Ilia Mirkin <imirkin@xxxxxxxxxxxx> wrote: >>> On Fri, Jul 15, 2016 at 9:12 AM, Peter Wu <peter@xxxxxxxxxxxxx> wrote: >>>> Hi, >>>> >>>> Here are two patches to fix an issue reported on kernel bugzilla (infinite loop >>>> due to unchecked function) and a more important fix to fix hanging Optimus >>>> machines when runtime PM is enabled (with pm/pci patches). >>>> >>>> These are the final patches targeting v4.8. Changes compared to v2[1]: >>>> collected R-b from Hans and Mika and fixed a minor comment style issue. >>>> >>>> I recommend it to be merged before the pci/pm patches[2], otherwise there is a >>>> window where newer Nvidia Optimus laptops might fail to runtime resume and/or >>>> lock up. Once the pci/pm branch is merged I will propose another patch to >>>> improve reliability[3]. >>>> >>>> Known issue with patch 4: when a Nvidia HDMI audio function is present, the >>>> bridge will not suspend and hence the Nvidia card will still be powered. Fixing >>> >>> That's basically all optimus gpu's, right? Anything GT21x+ has a HDMI >>> audio subfunction, and prior to that, the nvidia gpu tended to be the >>> only gpu, or hard-muxed. >> >> I'd imagine there is a strap on the asic so the audio function is only >> enabled if there is a connector actually wired to the dGPU. It >> doesn't make much sense to expose audio if there is no way to use it. > > A lot of the time, there actually is a connector wired up. A lot of > the other time, there is no connector, but the display unit is still > there. Very recently, NVIDIA gpu's have started coming out marked as > "3d accelerator", which sometimes but not always means that there's no > display unit, and for those, I would assume there is no audio > subfunction. > Just because there is a display block, doesn't mean the audio function is always enabled. I suspect it is disabled by hardware straps on systems with no display connectors or other specific OEM configs. Alex _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
