Raspberry Pi 5 unable to use multi-processor for memtest86

[Justinus]

Hello!

I am in the process of preparing several raspberry pi 5's for deployment over the next few months. I always use memtest86 to validate new hardware before deployment, and I was pleased to see that I can run it on Pi's as well (who knows when you'll get something with bad ram?)

Initially I was using it on 10.7, where it was unable to use multi-processor. After I saw the 11.0 update notes, I was pleased to see preliminary multi-processor support for ARM64 was added as it could help shave off a lot of time these pi's sit testing.

Sadly, it still fails to use multi-processor citing the same error as 10.7 - "[UEFI Firmware Error] Could not start CPU 1". I have attached the log.

In order to boot UEFI based operating systems, RPI requires a third party UEFI, found here: GitHub - worproject/rpi5-uefi: EDK2 firmware images for Raspberry Pi 5
Other operating systems booting from this UEFI are able to access and use all 4 processors, so I don't think it's an issue with the UEFI itself, although I cannot fully rule it out.

Any assistance would be appreciated.

[David (PassMark)]

Does V11 run OK with 1 thread active?

The ARM / UEFI multi-threading testing we did was more focused on the newer ARM Surface Laptops (the older ARM laptops also didn't support threading).

We'll take a look at the log.

[Justinus]

Yeah, by default it runs in single core mode and it runs normally.

[keith]

Thanks for the logs.

2024-03-16 03:44:52 - Testing MP support
2024-03-16 03:44:52 - MPSupportTestMPServices - AP dispatch test
2024-03-16 03:44:52 - MPSupportTestMPServices - Starting AP#1
2024-03-16 03:44:52 - MPSupportTestMPServices - Could not start AP#1 (Unsupported).
2024-03-16 03:44:52 - MPSupportTestMPServices - Waiting for AP's to complete execution
2024-03-16 03:44:52 - MPSupportTestMPServices - AP dispatch test complete
2024-03-16 03:44:52 - MP test failed. Setting default CPU mode to SINGLE

It appears that this particular UEFI implementation doesn't fully support multiprocessing when running in the UEFI pre-boot environment. Note that this is does not affect the multiprocessing behaviour after the O/S boots, where it is no longer running in the UEFI pre-boot environment.

So until there is updated firmware that supports multiprocessing, only single CPU mode is available.

[Justinus]

I'll take a look at the UEFI implementation and see if anything can be done. Thanks for the expert diagnosis!

[Mike2024]

I also have same problem In Arm Server，when MT86 run Multi Core Case，So my question is Arm And X86 Server can Use Protocol/MpService.h？

[David (PassMark)]

We have seen several ARM platforms that support multi-threading in UEFI BIOS (Microsoft got it working on their Surface ARM laptops for example). But also many that don't.

Honestly we are surprised it isn't working on all machines. Multi-threading isn't something new and it fairly fundamental for modern computing. So it is pretty surprising the ARM UEFI community never implemented it.