Comet Lake

Desktop Comet Lake

#Starting Point

So making a config.plist may seem hard, it's not. It just takes some time but this guide will tell you how to configure everything, you won't be left in the cold. This also means if you have issues, review your config settings to make sure they're correct. Main things to note with OpenCore:

• All properties must be defined, there are no default OpenCore will fall back on so do not delete sections unless told explicitly so. If the guide doesn't mention the option, leave it at default.

• The Sample.plist cannot be used As-Is, you must configure it to your system

• DO NOT USE CONFIGURATORS, these rarely respect OpenCore's configuration and even some like Mackie's will add Clover properties and corrupt plists!

Now with all that, a quick reminder of the tools we need

• ProperTree(opens new window)

  • Universal plist editor

• GenSMBIOS(opens new window)

  • For generating our SMBIOS data

• Sample/config.plist(opens new window)

  • See previous section on how to obtain: config.plist Setup

WARNING

Read this guide more than once before setting up OpenCore and make sure you have it set up correctly. Do note that images will not always be the most up-to-date so please read the text below them, if nothing's mentioned then leave as default.

#ACPI

#Add

Info

This is where you'll add SSDTs for your system, these are very important to booting macOS and have many uses like USB maps (opens new window), disabling unsupported GPUs and such. And with our system, it's even required to boot. Guide on making them found here: Getting started with ACPI(opens new window)

For us we'll need a couple of SSDTs to bring back functionality that Clover provided:

Note that you should not add your generated DSDT.aml here, it is already in your firmware. So if present, remove the entry for it in your config.plist and under EFI/OC/ACPI.

For those wanting a deeper dive into dumping your DSDT, how to make these SSDTs, and compiling them, please see the Getting started with ACPI (opens new window)page. Compiled SSDTs have a .aml extension(Assembled) and will go into the EFI/OC/ACPI folder and must be specified in your config under ACPI -> Add as well.

#Delete

This blocks certain ACPI tables from loading, for us we can ignore this.

#Patch

This section allows us to dynamically modify parts of the ACPI (DSDT, SSDT, etc.) via OpenCore. For us, our patches are handled by our SSDTs. This is a much cleaner solution as this will allow us to boot Windows and other OSes with OpenCore

#Quirks

Settings relating to ACPI, leave everything here as default as we have no use for these quirks.

#Booter

This section is dedicated to quirks relating to boot.efi patching with OpenRuntime, the replacement for AptioMemoryFix.efi

#MmioWhitelist

This section is allowing devices to be passthrough to macOS that are generally ignored, for us we can ignore this section.

#Quirks

Info

Settings relating to boot.efi patching and firmware fixes, for us, we need to change the following:

#DeviceProperties

#Add

Sets device properties from a map.

PciRoot(0x0)/Pci(0x2,0x0)

This section is set up via WhateverGreen's Framebuffer Patching Guide (opens new window)and is used for setting important iGPU properties. If you have a -F series CPU, you can ignore this section as you do not have an iGPU.

The config.plist doesn't already have a section for this so you will have to create it manually.

AAPL,ig-platform-id is what macOS uses to determine how the iGPU drivers interact with our system, and two values choose between are as follows:

• Note: With macOS 10.15.5 and newer, there seems to be a lot of issues with black screen using 07009B3E, if you get similar issues try swapping to 00009B3E

We also add 2 more properties, framebuffer-patch-enable and framebuffer-stolenmem. The first enables patching via WhateverGreen.kext, and the second sets the min stolen memory to 19MB. This is usually unnecessary, as this can be configured in BIOS(64MB recommended) but required when not available.

• Note: Headless framebuffers(where the dGPU is the display out) do not need framebuffer-patch-enable and framebuffer-stolenmem

(This is an example for a desktop UHD 630 without a dGPU and no BIOS options for iGPU memory)

PciRoot(0x0)/Pci(0x1C,0x1)/Pci(0x0,0x0)

This entry relates to Intel's I225-V 2.5GBe controller found on higher end Comet Lake boards, what we'll be doing here is tricking Apple's I225LM driver into supporting our I225-V network controller:

• Note: If your board didn't ship with the Intel I225 NIC, there's no reason to add this entry.

• Note 2: If you get a kernel panic on the AppleIntelI210Ethernet kext, your Ethernet's path is likely PciRoot(0x0)/Pci(0x1C,0x4)/Pci(0x0,0x0)

PciRoot(0x0)/Pci(0x1b,0x0)

layout-id

• Applies AppleALC audio injection, you'll need to do your own research on which codec your motherboard has and match it with AppleALC's layout. AppleALC Supported Codecs (opens new window).

• You can delete this property outright as it's unused for us at this time

For us, we'll be using the boot-arg alcid=xxx instead to accomplish this. alcid will override all other layout-IDs present. More info on this is covered in the Post-Install Page(opens new window)

#Delete

Removes device properties from the map, for us we can ignore this

#Kernel

#Add

Here's where we specify which kexts to load, in what specific order to load, and what architectures each kext is meant for. By default we recommend leaving what ProperTree has done, however for 32-bit CPUs please see below:

#Emulate

Needed for spoofing unsupported CPUs, thankfully in 10.15.5+ Comet Lake S support was added so no need to spoof here. For those running High Sierra or Mojave, you will need the below to spoof to a supported CPU model(due to stability issues, this guide will not go over such CPUID spoofs)

#Force

Used for loading kexts off system volume, only relevant for older operating systems where certain kexts are not present in the cache(ie. IONetworkingFamily in 10.6).

For us, we can ignore.

#Block

Blocks certain kexts from loading. Not relevant for us.

#Patch

Patches both the kernel and kexts.

Fixing I225-V controllers

This entry relates to Intel's I225-V 2.5GBe controller found on higher end Comet Lake boards, what we'll be doing here is tricking Apple's I225LM driver into supporting our I225-V network controller. However, this is only needed on Catalina and Big Sur, up to 11.3.

• Note 1: If your board didn't ship with the Intel I225 NIC, there's no reason to add this entry.

• Note 2: Leave all other keys at their default values

#Quirks

Info

Settings relating to the kernel, for us we'll be enabling the following:

#Scheme

Settings related to legacy booting(ie. 10.4-10.6), for majority you can skip however for those planning to boot legacy OSes you can see below:

#Misc

#Boot

Info

#Debug

Info

Helpful for debugging OpenCore boot issues(We'll be changing everything but DisplayDelay):

#Security

Info

Security is pretty self-explanatory, do not skip. We'll be changing the following:

#Serial

Used for serial debugging (Leave everything as default).

#Tools

Used for running OC debugging tools like the shell, ProperTree's snapshot function will add these for you.

#Entries

Used for specifying irregular boot paths that can't be found naturally with OpenCore.

Won't be covered here, see 8.6 of Configuration.pdf (opens new window)for more info

#NVRAM

#Add

4D1EDE05-38C7-4A6A-9CC6-4BCCA8B38C14

Used for OpenCore's UI scaling, default will work for us. See in-depth section for more info

4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102

OpenCore's NVRAM GUID, mainly relevant for RTCMemoryFixup users

7C436110-AB2A-4BBB-A880-FE41995C9F82

System Integrity Protection bitmask

• General Purpose boot-args:

• Networking-Specific boot-args:

• GPU-Specific boot-args:

• csr-active-config: 00000000

  • Settings for 'System Integrity Protection' (SIP). It is generally recommended to change this with csrutil via the recovery partition.

  • csr-active-config by default is set to 00000000 which enables System Integrity Protection. You can choose a number of different values but overall we recommend keeping this enabled for best security practices. More info can be found in our troubleshooting page: Disabling SIP

• run-efi-updater: No

  • This is used to prevent Apple's firmware update packages from installing and breaking boot order; this is important as these firmware updates (meant for Macs) will not work.

• prev-lang:kbd: <>

  • Needed for non-latin keyboards in the format of lang-COUNTRY:keyboard, recommended to keep blank though you can specify it(Default in Sample config is Russian):

  • American: en-US:0(656e2d55533a30 in HEX)

  • Full list can be found in AppleKeyboardLayouts.txt(opens new window)

  • Hint: prev-lang:kbd can be changed into a String so you can input en-US:0 directly instead of converting to HEX

  • Hint 2: prev-lang:kbd can be set to a blank variable (eg. <>) which will force the Language Picker to appear instead at first boot up.

#Delete

Info

Forcibly rewrites NVRAM variables, do note that Add will not overwrite values already present in NVRAM so values like boot-args should be left alone. For us, we'll be changing the following:

#PlatformInfo

Info

For setting up the SMBIOS info, we'll use CorpNewt's GenSMBIOS (opens new window)application.

For this Comet Lake example, we'll chose the iMac20,1 SMBIOS - this is done intentionally for compatibility's sake. There are two main SMBIOS used for Comet Lake:

Run GenSMBIOS, pick option 1 for downloading MacSerial and Option 3 for selecting out SMBIOS. This will give us an output similar to the following:

  #######################################################
 #               iMac20,1 SMBIOS Info                  #
#######################################################

Type:         iMac20,1
Serial:       C02XG0FDH7JY
Board Serial: C02839303QXH69FJA
SmUUID:       DBB364D6-44B2-4A02-B922-AB4396F16DA8

• Note: MacSerial currently does not support Linux, so you must grab a Windows or macOS machine to generate the values

The Type part gets copied to Generic -> SystemProductName.

The Serial part gets copied to Generic -> SystemSerialNumber.

The Board Serial part gets copied to Generic -> MLB.

The SmUUID part gets copied to Generic -> SystemUUID.

We set Generic -> ROM to either an Apple ROM (dumped from a real Mac), your NIC MAC address, or any random MAC address (could be just 6 random bytes, for this guide we'll use 11223300 0000. After install follow the Fixing iServices (opens new window)page on how to find your real MAC Address)

Reminder that you need an invalid serial! When inputting your serial number in Apple's Check Coverage Page (opens new window), you should get a message such as "Unable to check coverage for this serial number."

Automatic: YES

• Generates PlatformInfo based on Generic section instead of DataHub, NVRAM, and SMBIOS sections

#Generic

#UEFI

ConnectDrivers: YES

• Forces .efi drivers, change to NO will automatically connect added UEFI drivers. This can make booting slightly faster, but not all drivers connect themselves. E.g. certain file system drivers may not load.

#Drivers

Add your .efi drivers here.

Only drivers present here should be:

• HfsPlus.efi

• OpenRuntime.efi

#APFS

By default, OpenCore only loads APFS drivers from macOS Big Sur and newer. If you are booting macOS Catalina or earlier, you may need to set a new minimum version/date. Not setting this can result in OpenCore not finding your macOS partition!

macOS Sierra and earlier use HFS instead of APFS. You can skip this section if booting older versions of macOS.

APFS Versions

Both MinVersion and MinDate need to be set if changing the minimum version.

#Audio

Related to AudioDxe settings, for us we'll be ignoring(leave as default). This is unrelated to audio support in macOS.

• For further use of AudioDxe and the Audio section, please see the Post Install page: Add GUI and Boot-chime(opens new window)

#Input

Related to boot.efi keyboard passthrough used for FileVault and Hotkey support, leave everything here as default as we have no use for these quirks. See here for more details: Security and FileVault(opens new window)

#Output

Relating to OpenCore's visual output, leave everything here as default as we have no use for these quirks.

#ProtocolOverrides

Mainly relevant for Virtual machines, legacy macs and FileVault users. See here for more details: Security and FileVault(opens new window)

#Quirks

Info

Relating to quirks with the UEFI environment, for us we'll be changing the following:

#ReservedMemory

Used for exempting certain memory regions from OSes to use, mainly relevant for Sandy Bridge iGPUs or systems with faulty memory. Use of this quirk is not covered in this guide