https://bugzilla.kernel.org/show_bug.cgi?id=93281 Roland Scheidegger <rscheidegger@xxxxxx> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |rscheidegger@xxxxxx --- Comment #11 from Roland Scheidegger <rscheidegger@xxxxxx> --- FWIW I've got the same notebook and I can confirm the gmux is problematic (the apple-gmux driver should support it in theory). Though I don't think it ever hanged for me, but you can easily lose the display on bootup depending on how you boot - there's essentially 3 different methods: 1) via CSM bios emulation. In this case you will get working AMD graphics, with no ability to switch to the intel one (it does not even appear in the pci device list). 2) via direct efi boot (refind or similar). This will get you working AMD graphics like the above, with the theoretical ability to switch to the intel one with vgaswitcheroo as it is now properly enumerated and the apple-gmux driver used, however switching does not actually work (it seems the intel graphics only works if it was active on boot in my experiments). (*) 3) via grub-efi (looks like this is what you do?). Unfortunately this will not work without extra grub parameters, because the radeon graphics bios cannot be retrieved (though last I looked there was some discussion about fixing this in grub, so it may work with a newer grub version). The grub parameters are to force the mux to switch to intel graphics, in which case you get working intel (but not amd) graphics, though you won't see initial bootup messages before kms is loaded. (Note that after suspend/resume, the AMD chip will be powered on but unused again for some needlessly higher (IIRC over 5W) power consumption, though you can write a hack app to force it off again.) This page has some information on this - in particular the 4 outb commands for the grub config: http://blog.tkassembled.com/364/intel-graphics-on-a-2011-macbook-pro-in-linux/ (*) I actually got switching graphics to work as a proof-of-concept by using direct efi boot and forcing the gmux to intel by using the efi console, though halfway through you will lose the screen in there and have to remember what keystrokes are needed to select the right boot entry in the refind menu... -- You are receiving this mail because: You are watching the assignee of the bug. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
