[Solved] Help with HD 4000 on Big Sur

[Stacey]

Hello guys, I have a problem regarding HD 4000.

 

Using the patch below HDMI works, but on the laptop the screen is unstable, and glitches appear all the time.

 

<key>PciRoot(0x0)/Pci(0x2,0x0)</key>
  <dict>
  <key>framebuffer-con1-enable</key>
  <integer>1</integer>
  <key>framebuffer-con1-flags</key>
  <data>BgAAAA==</data>
  <key>framebuffer-con1-type</key>
  <data>AAgAAA==</data>
  <key>framebuffer-con2-enable</key>
  <integer>1</integer>
  <key>framebuffer-con2-flags</key>
  <data>BgAAAA==</data>
  <key>framebuffer-con2-type</key>
  <data>AAgAAA==</data>
  <key>framebuffer-con3-enable</key>
  <integer>1</integer>
  <key>framebuffer-con3-flags</key>
  <data>BgAAAA==</data>
  <key>framebuffer-con3-type</key>
  <data>AAgAAA==</data>
  <key>AAPL,ig-platform-id</key>
  <data>AwBmAQ==</data>
  <key>hda-gfx</key>
  <string>onboard-1</string>
  </dict>

 

However with the patch below the notebook screen works without glitchs, however HDMI is not detected.

 

<key>PciRoot(0x0)/Pci(0x2,0x0)</key>
  <dict>
  <key>AAPL,ig-platform-id</key>
  <data>
  AwBmAQ==
  </data>
  <key>framebuffer-con1-alldata</key>
  <data>
  BQMAAAIAAAAwAgAA
  </data>
  <key>framebuffer-con1-enable</key>
  <integer>1</integer>
  <key>framebuffer-fbmem</key>
  <data>
  AACAAA==
  </data>
  <key>framebuffer-memorycount</key>
  <integer>2</integer>
  <key>framebuffer-patch-enable</key>
  <integer>1</integer>
  <key>framebuffer-pipecount</key>
  <integer>2</integer>
  <key>framebuffer-portcount</key>
  <integer>4</integer>
  <key>framebuffer-stolenmem</key>
  <data>
  AAAABA==
  </data>
  <key>hda-gfx</key>
  <string>onboard-1</string>
  </dict>

 

Any tips on how to get HDMI working on this second patch?

[Jake Lo]

You need to determine which port is your HDMI.

In the 1st patch, you have con1, 2, and 3 set to HDMI. If you could post an IOReg file with the 1st config file, we could help you patch it to your 2nd config

Use IORegistryExplorer.app v2.1, export, compress and attach it here.

 

By the way, it would help even further if you could post the full system specs so no guessing game needed.

[Hervé]

It's the fbmem patch that prevents the graphics glitches and defects as explained in our HD4000 patching guide; so make sure you implement it. You do not modify/patch memory count, pipe count, port count or stolenmem with LoRes/4-port layout 0x01660003, only with HiRes/1-port layout 0x01660004.

 

Therefore, your framebuffer patch for iGPU@2 should set the following parameters to the following values:

ig-platform-id -> 03006601         // LoRes/4-port Capri mobile layout
framebuffer-patch-enable -> 1      // enables framebuffer patching
framebuffer-fbmem -> 00008000      // reduces framebuffer memory from default 16MB to 8MB
framebuffer-conX-enable -> 1       // enables conX patching, where X is your identified connector for HDMI output port
framebuffer-conX-type -> 00080000  // sets conX to HDMI type, where X is your identified connector for HDMI output port
hda-gfx -> onboard-1               // for HDMI-audio

and nothing else. Target connector will most probably be con1.

 

In the future, please post system's specs (add those in signature!) and copy of your bootloader config so that it can be properly read with the relevant tools, rather then leave people use Base64 to Hex/Text converter to decode your patches... Here, we assessed it was a Clover config but also specify this sort of things.

 

For a complete and detailed set of information on framebuffer patching, I invite you to consult the Whatevergreen user manual:

https://github.com/acidanthera/WhateverGreen/blob/master/Manual/FAQ.IntelHD.en.md

[Stacey]

Works as a charm.