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/
- Macbook Pro Retina 15 Late 2013
- Intel Iris Pro Graphics
- NVIDIA GeForce GT 750M with 2GB of GDDR5 memory and automatic graphics switching
- Tails (running via usb flash disc and/or sd card)
- based on Debian Wheezy
active gpu: Nvidia GT 750m 2GB
desired 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)
- osx: none. ssd disk empty
- battery life: 2 hours maximum
- battery life when underclocked to +-40% and turbo deactivated: 3h 45 minutes approximately
01:00.0 VGA compatible controller: NVIDIA Corporation Device 0fe9 (rev a1) (prog-if 00 [VGA controller]) Subsystem: Apple Inc. Device 0130 Flags: bus master, fast devsel, latency 0, IRQ 48 Memory 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:  Power Management version 3 Capabilities:  MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities:  Express Endpoint, MSI 00 Capabilities: [b4] Vendor Specific Information: Len=14 Capabilities:  Virtual Channel Capabilities:  Power Budgeting Capabilities:  Advanced Error Reporting Capabilities:  Vendor Specific Information: ID=0001 Rev=1 Len=024 Capabilities:  #19 Kernel driver in use: nouveau
issue: 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.
(from the link above:)
This prevents the firmware from powering down the integrated graphics card on some recent 2013 Macbook Pro laptops.
Basically 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 card
Any ideas how to accomplish using IGP in Tails? a.k.a how to integrate apple_set_os inside of bootloader of Tails?