On Fri, Jun 21, 2013 at 12:54 PM, Alexander E. Patrakov <[email protected]> wrote: > 2013/6/21 Maarten Lankhorst <[email protected]>: >> Op 21-06-13 12:43, Alexander E. Patrakov schreef: >>> 2013/6/21 Maarten Lankhorst <[email protected]>: >>>> For the open source drivers there should be a different way to do so, try >>>> running this before starting X: >>>> >>>> if [ -f /sys/kernel/debug/vgaswitcheroo/switch]; then >>>> echo DIS > /sys/kernel/debug/vgaswitcheroo/switch >>>> echo ON > /sys/kernel/debug/vgaswitcheroo/switch >>>> fi >>> According to https://help.ubuntu.com/community/HybridGraphics: >>> >>> echo DIS > /sys/kernel/debug/vgaswitcheroo/switch >>> Connects discrete graphics with outputs. >>> >>> I assume this is for laptops that can dynamically switch their HDMI or >>> other outputs from one card to another. However, this is completely >>> different from what my Sony laptop provides. The cards and their >>> outputs are physically separate. The Intel card is in the laptop, and >>> can drive the internal panel, the VGA and the HDMI output. The Radeon >>> card is in the dock station, is always on (there is no ATPX method in >>> ACPI tables), works only from AC and has its own VGA and HDMI outputs, >>> also located on the dock station. So this laptop, when docked, can >>> drive five different displays, including the internal one. And I want >>> to connect the TV to the HDMI output in the dock station because it is >>> convenient (less cables attached to the side of the laptop itself). >>> >>> As I am physically away from this laptop, I cannot check whether >>> vgaswitcheroo works (but assume it shouldn't). >> Correct, but it should work on muxless too, switching will power off the >> intel, which is >> why you have the second line.. It will re-enable the intel, but keep radeon >> as primary, >> similar to what you are doing with -gpu 1. > > The problem is that I have CONFIG_VGA_SWITCHEROO=y in my kernel, but > no /sys/kernel/debug/vgaswitcheroo. Let me rephrase the question: > would you expect this directory to exist in a desktop system with two > GPUs, one onboard and one installed by yourself into a PCIe slot, but > with the BIOS always insisting that the onboard one is the primary > VGA? >
/sys/kernel/debug/vgaswitcheroo only exists on laptops that have explicit platform controls (ACPI or other platofrm specific solution) for enabling/disabling the discrete GPU and switching the display/ddc muxes. You won't have vgaswitcheroo on systems with arbitrary user added cards. Alex _______________________________________________ [email protected]: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
