Hi Michael, On Sat, Feb 13, 2016 at 10:36:47PM -0800, Michael Marineau wrote: > On Feb 13, 2016 9:38 PM, "Matthew Garrett" <mjg59@xxxxxxxxxxxxx> wrote: > > > > On Sun, Feb 14, 2016 at 12:39:12AM +0100, Lukas Wunner wrote: > > > @Bjorn Helgaas: Do you think this masquerade patch would be eligible > > > for inclusion in the kernel or is this not in your department? > > > https://www.marc.info/?l=grub-deavel&m=141586614924917&w=2 > > > > I think this is an entirely appropriate piece of code to add to the EFI > > boot code in the kernel. > > One note on that code: making the Intel card visible exposes a number of > other bugs such as power management with nouveau not working any more and > despite vga switcheroo becoming available it isn't possible to switch to > the Intel gpu because, at least on my machine, neither the Intel nor > nouveau drivers can figure out how to bring up the eDP link or some such. That is correct. GPU switching for pre-retinas was finally queued for 4.6 this week, retinas are my next target. To overcome the link training issues I had experimented with AUX proxying last year until I realized in December that the DP spec has a link training exemption for eDP. Basically what we need to do is wait until the active GPU has set up its eDP output, then communicate voltage swing, pre-emphasis, lane count etc to the inactive GPU's driver (via vga_switcheroo) and use these pre-calibrated values to set up the output. I've hacked together an initial implementation of the i915 and vga_switcheroo side of things in early January, then got side-tracked while working on the nouveau part. However I'll get back to this pretty soon. Best regards, Lukas -- To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html