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Lenovo Yoga 2 Pro HD4400 QHD+ QE/CI working

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Success!!! I finally made it (just by putting together the efforts of others to be honest)
I now have QE/CI on a Yoga 2 Pro with QHD+ 3200x1800 including working touchscreen (out-of-the-box)
(without directly moding the bios, just doing it by UEFI setup_var)

A short collection of what I had to put together (only directly valid for Yoga 2 Pro owners!):
- I am using bootloader Clover with Yosemite 10.10.3
- I found, nearly 10 month ago, the needed steps by the godfather of the solution the_darkvoid
[Guide] Dell XPS 9530 using Clover UEFI
- On Yoga 2 Pro the problem was that you couldn't change the DVMT Pre-Allocated to 96MB, because you cannot "easily" flash a modded bios to the Y2P
- but I found an alternative solution from Austere.J by using a custom EFI-Shell based on grub
- thanks also to donovan6000 for his tools and excellent explanations
- thanks to FireWolf for his EFI Shell function setup_var

To change the DVMT Parameter on Y2P you have to use "setup_var 0x18c 0x03" (for 96MB)
(this may also apply for other Insyde BIOS)
Under Windows it shows 64MB (+32MB) as dedicated video memory

- To patch the maximum pixel clock for QHD+ I patched the IOKit (that sadly cannot be done by Clover)
- Thanks to the_darkvoid again
[Guide] Dell XPS 9530 using Clover UEFI

Just execute macPixelClockPatcher.command

- I used FakePCIID for HD4400 to have the best graphics results, thanks to Rehabman and the_darkvoid

- Finally the hint of RehabMan to use 0xa2e0008 an patch to 96MB was the final solution
I recommand to use his config_HD4600_4400_4200.plist as a basis

Annotation: RehabMan already added the DVMT block. You just have to remove "disabled:".

!!These are just exerpts of the main important setting you have to add in your config.plist!!

<string>HD4400 Azul Framebuffer Size 96MB</string>


Attached you find the config.plist, the BIOS Version 76CN38WW and the DisplayVendorID i used.

I hope this brief compilation is of any help to other Yoga 2 Pro Owners.




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