05-03-2022, 07:57 AM
(This post was last modified: 05-03-2022, 08:04 AM by TheSynthax.)
Hello, I have an old-ish iMac and a 9900K laying around I'm experimenting with. I'm attempting a CoffeeLake mod on its EFI. So far I've downgraded the ME firmware in the bios I dumped by grabbing an older firmware for this machine and extracting the ME FW from that. I've inserted the microcode for my SRG19 version of the 9900K (906ED mcode) which I've pulled out of the 2019 iMac's firmware. I seem to be running into an issue with a checksum in the Volume Top File, or so I believe. Editing the pad file which contains the microcode on these machines causes an error in UEFITool when loading the modified firmware
"FfsParser::findFitRecursive: FIT table candidate found, but not referenced from the last VTF"
I suspected this could possibly be due to moving the position of the FIT table in the microcode file at first, but leaving it at the same address results in the same issue and a non-booting system, leading me to believe this to be a checksum problem. The firmware very well may need further modifications to play nice with the drastically newer CPU, but that's why this is just an experimental project. Here's the files I'm working with https://www.dropbox.com/sh/0wtomvxujwijc...dmk7a?dl=0
iMac2015dmp.bin (Size: 8 MB / Downloads: 2)
"FfsParser::findFitRecursive: FIT table candidate found, but not referenced from the last VTF"
I suspected this could possibly be due to moving the position of the FIT table in the microcode file at first, but leaving it at the same address results in the same issue and a non-booting system, leading me to believe this to be a checksum problem. The firmware very well may need further modifications to play nice with the drastically newer CPU, but that's why this is just an experimental project. Here's the files I'm working with https://www.dropbox.com/sh/0wtomvxujwijc...dmk7a?dl=0
iMac2015dmp.bin (Size: 8 MB / Downloads: 2)