Effects of flashing ME version intended for another SKU

[wolf606]

My plan is to flash the ME firmware extracted from the MBP131.fd, a MacBook Pro 13,1 firmware update file, onto a Lenovo Ideapad 500 - 14ISK laptop.

I ran the ME Analyzer on both the Mac and Lenovo ME firmware and the only difference is the SKU.

I’m using the CH341A to program the chip, so I can recover it to a functional state if it fails to boot. But besides that, I’d like to know the consequences and effects of flashing a ME firmware intended for another SKU.

[lfb6]

What would be the meaning of such an attempt?

[wolf606]

Some ME firmware have the Apple Guc key hash. That’s necessary for loading the iGPU microcode under macOS. I already checked if the Lenovo ME FW has the key (it doesn’t). So the point of doing this is to enable a functionality on macOS

[lfb6]

You’re aware of the many configuration options an Intel ME has and have knowledge of the program (Flash Image Tool) used to adjust them?

See:

Intel (Converged Security) Management Engine: Drivers, Firmware and Tools (2-15)

Intel (Converged Security) Management Engine: Drivers, Firmware and Tools for (CS)ME 2-15 Last Updated: 2022-09-08 Intel Management Engine Introduction: Built into many Intel-based platforms is a small, low power computer subsystem called the Intel Management Engine (Intel ME). This can perform various tasks while the system is booting, running or sleeping. It operates independently from the main CPU, BIOS and OS but can interact with them if needed. The ME is responsible for many parts of a…

In addition an update file may or may not contain a proper configuration.

(Never worked with an Apple ME though…)

[wolf606]

So it would be possible to enable the Apple Guc key with Flash Image Tool? I’m going to check that out. Regarding to the configuration file, it may need adjustments.

But my question still is, let’s say the ME firmware I flashed on the Lenovo laptop is corrupted (bad configuration) or no supported because of the SKU. Is it possible to damage the hardware or the ME functionality (fuses data corruption or something) in an unrecoverable way? Taking in to account I have a copy from the original SPI image that is extracted with a programmer.

[lfb6]

Theoretically yes if the machine hasn’t set end of manufacturing and the FPFs aren’t fused yet. But that’s not very probable for a Lenovo.And programming for the integrated clock controller is also done in the ME.