On Mon, Sep 10, 2012 at 2:31 PM, Dave Airlie <airlied@xxxxxxxxx> wrote: > For optimus and powerxpress setups where we can explicitly power off > the GPU I'd like to do this under control of the driver. Now that I've > added X server support for secondary GPUs, it makes sense to start > powering them down more often if we can. > > I've tested this code on two laptops, one intel/nouveau one intel/radeon > It works, powertop says I use 5-6W less power. > > Caveats: > There is a race at X server start with platform probing code, if > the secondary device is off, we the wrong PCI info for it, I've > got a patch that works around this I'll send to the xorg-devel. > > Audio seems to get screwed at least on one machine, we power up > and the alsa callbacks into snd_hda_intel get called but it can't > find the hw properly, need to investigate a bit further. > > Dave. > Hi Takashi, just wondering how well setup alsa would be for the dGPU powering up/down a lot more often, 139.529103] nouveau [ DRM][0000:01:00.0] resuming display... [ 139.833960] ALSA sound/pci/hda/hda_intel.c:2533 Enabling 0000:01:00.1 via VGA-switcheroo [ 139.844789] snd_hda_intel 0000:01:00.1: Refused to change power state, currently in D3 [ 139.915760] snd_hda_intel 0000:01:00.1: Refused to change power state, currently in D3 [ 140.917437] ALSA sound/pci/hda/hda_intel.c:813 spurious response 0x0:0x3, last cmd=0x301f0500 [ 140.917449] ALSA sound/pci/hda/hda_intel.c:813 spurious response 0x0:0x3, last cmd=0x301f0500 [ 140.917455] ALSA sound/pci/hda/hda_intel.c:813 spurious response 0x0:0x3, last cmd=0x301f0500 [ 140.917460] ALSA sound/pci/hda/hda_intel.c:813 spurious response 0x0:0x3, last cmd=0x301f0500 [ 140.917465] ALSA sound/pci/hda/hda_intel.c:813 spurious response 0x0:0x3, last cmd=0x301f0500 is just some of the things I see, if I turn off before snd_hda_intel, things go badly wrong when I do power up the dGPU, if I delay the power off until audio is loaded, I start to see wierd things when pulseaudio starts when the dGPU is off. Dave. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
