jaymonkey
Moderator
- Joined
- Aug 27, 2011
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- GB Z490 Vision D
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- i9-10850K OC @ 5.2 GHz
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@hyphenbash, @Baasjebram, @leeyee, @raubiero
Most genuine Mac's have two banks of RTC memory (2 x 128 bytes), The first bank is used for storing the Real Time Clock, Date, etc (as it is on a PC). The second bank is used by MacOS to store some system variables including the hibernation crypro key.
FakeSMC (Or VirtualSMC) move most of the important RTC variables to NVRAM so i's not an issue for us, the only thing it does not handle is the crypto key for the hibernation file which is always stored in the second bank of RTC memory.
I think on newer Macs the RTC memory has been replaced by the T2 chip but i'm not 100% certain.
Many PC's only have one bank of RTC memory (128 bytes) so it's pretty normal to see the warning `RTC: Only single RAM bank (128 bytes)' in the kernel boot log. It's not a show stopper and can be safely ignored.
If native MacOS Hibernation is important to you there is a Lilu plug-in that will save and read the hibernation file's crypto key to and from NVRAM rather than RTC Memory but it does require native NVRAM to be fully 100% working (you can not use Emulated NVRAM).
github.com
However I would not recommend using it on older PC hardware, and you should really disable MacOS Hibernation as recommended by most guides.
Cheers
Jay
Most genuine Mac's have two banks of RTC memory (2 x 128 bytes), The first bank is used for storing the Real Time Clock, Date, etc (as it is on a PC). The second bank is used by MacOS to store some system variables including the hibernation crypro key.
FakeSMC (Or VirtualSMC) move most of the important RTC variables to NVRAM so i's not an issue for us, the only thing it does not handle is the crypto key for the hibernation file which is always stored in the second bank of RTC memory.
I think on newer Macs the RTC memory has been replaced by the T2 chip but i'm not 100% certain.
Many PC's only have one bank of RTC memory (128 bytes) so it's pretty normal to see the warning `RTC: Only single RAM bank (128 bytes)' in the kernel boot log. It's not a show stopper and can be safely ignored.
If native MacOS Hibernation is important to you there is a Lilu plug-in that will save and read the hibernation file's crypto key to and from NVRAM rather than RTC Memory but it does require native NVRAM to be fully 100% working (you can not use Emulated NVRAM).
GitHub - acidanthera/HibernationFixup: A Lilu plugin intended to fix hibernation compatibility issues
A Lilu plugin intended to fix hibernation compatibility issues - acidanthera/HibernationFixup
github.com
However I would not recommend using it on older PC hardware, and you should really disable MacOS Hibernation as recommended by most guides.
Cheers
Jay
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