Macbook Pro 15 Retina Late 2013 uses explicitly dedicated GPU. Integrated graphic processor isn't listed at all.Not being able to switch or turn off discrete card to improve battery life./preambula: I am hitting my head past 2 weeks not able to do any first step at this as it is the last and most important issue that I need to solve/hw:Macbook Pro Retina 15 Late 2013Intel Iris Pro GraphicsNVIDIA GeForce GT 750M with 2GB of GDDR5 memory and automatic graphics switchingos:Tails (running via usb flash disc and/or sd card)based on Debian Wheezyboot:syslinuxactive gpu:Nvidia GT 750m 2GBdesired gpu:Intel Iris Pro (all the time if not able to switch automatically)goal: battery life, mostly no need to use dedicated gpu (at all)additional info:osx: none. ssd disk emptybattery life: 2 hours maximumbattery life when underclocked to +-40% and turbo deactivated: 3h 45 minutes approximatelylspci:01:00.0 VGA compatible controller: NVIDIA Corporation Device 0fe9 (rev a1) (prog-if 00 [VGA controller])Subsystem: Apple Inc. Device 0130Flags: bus master, fast devsel, latency 0, IRQ 48Memory at c0000000 (32-bit, non-prefetchable) [size=16M]Memory at 80000000 (64-bit, prefetchable) [size=256M]Memory at 90000000 (64-bit, prefetchable) [size=32M]I/O ports at 1000 [size=128]Expansion ROM at c1000000 [disabled] [size=512K]Capabilities: [60] Power Management version 3Capabilities: [68] MSI: Enable+ Count=1/1 Maskable- 64bit+Capabilities: [78] Express Endpoint, MSI 00Capabilities: [b4] Vendor Specific Information: Len=14Capabilities: [100] Virtual ChannelCapabilities: [128] Power BudgetingCapabilities: [420] Advanced Error ReportingCapabilities: [600] Vendor Specific Information: ID=0001 Rev=1 Len=024Capabilities: [900] #19Kernel driver in use: nouveauissue:There are many services like vgaswitcheroo, acpi_call etc. However, none of them can work if the IGP (in this case Intel Iris Pro) is not listed at all. Reason: it is not powered / recognized / enabled during the boot.possible solution: https://www.marc.info/?l=grub-deavel&m=141586614924917&w=2https://github.com/0xbb/gpu-switch(from the link above:)This prevents the firmware from powering down the integrated graphics  card on some recent 2013 Macbook Pro laptops.apple_set_os commandBasically Macbook Pros detect that system being loaded isn't OS X and the hardware recognization differs. Which results into internal IGP powered down.desired solution: Be able to hardcode this solution into the kernel of Tails by myself to use explicitly the IGP (Intel Iris Pro Graphics) or be able to switch off to the integrated graphic cardAny ideas how to accomplish using IGP in Tails? a.k.a how to integrate apple_set_os inside of bootloader of Tails?
enabling Intel Iris Pro (syslinux, Tails system, Macbook Pro 15 Retina Late 2013, IGP/GPU)
debian;boot;macintosh;syslinux;tails os