Updated AMD Zen 1 Through Zen 3 CPU Microcode Published

[phoronix]

Phoronix: Updated AMD Zen 1 Through Zen 3 CPU Microcode Published

On Friday AMD published new CPU microcode files for both Family 17h and Family 19h for Zen 1/2/3 processors. At the moment there isn't any public insight into the changes with this updated microcode but it may be significant...

https://www.phoronix.com/scan.php?page=news_item&px=Zen-1-To-Zen-3-2022-AMD-ucode

[Jabberwocky]

Not even making the effort of lying to us. I feel neglected. xD

Seriously, thanks for observing and documenting this Michael.

[Nuc!eoN]

Very weird.

I hope it does not have anything to to with their PSP module.

EDIT, for those that do not know what it is:

The PSP is an ARM Cortex A5 with some private SRAM, a hardware crypto engine (a rather impressive one, if I may add), and on chip boot rom. The PSP has unlimited DMA access into every memory region, and can even override the IOMMU.

It features an fully fledged operating system, called "Kinibi" (formerly <t-base) by Trustonic. It loads various drivers and applications during bootup. One of them is the fTPM, which is a trusted application emulating a TPM module.

On Ryzen processors with integrated graphics, HDCP is handled by the PSP. It is also responsible for DRAM initialization, and supervises the boot process.

[boxie]

Given the recent bios updates for x370 I wonder if it is related?

[middy]

Given the recent bios updates for x370 I wonder if it is related?

i had a similar thought. first gen ryzen might need firmware updates to work on newer agesa.

[Developer12]

Given the recent bios updates for x370 I wonder if it is related?

The new bios updates are almost certainly to distribute the new microcode. For a long time CPU manufacturers have been cagy about allowing the OS to do the updates, preferring that the BIOS do it before the OS even loads.

[Developer12]

Very weird.

I hope it does not have anything to to with their PSP module.

EDIT, for those that do not know what it is:

afaik the PSP and microcode are completely separate. The microcode reconfigures the operation of the main cores' pipelines. The PSP is an entierly separate ARM-based computer living on the same chip.

[evil_core]

afaik the PSP and microcode are completely separate. The microcode reconfigures the operation of the main cores' pipelines. The PSP is an entierly separate ARM-based computer living on the same chip.

But you don't 'burn' new microcode into CPU, but it must be provided by OS/bootloader everytime on boot or be flashed to M/B BIOS/EFI(and be loaded every boot to CPU)

[Developer12]

But you don't 'burn' new microcode into CPU, but it must be provided by OS/bootloader everytime on boot or be flashed to M/B BIOS/EFI(and be loaded every boot to CPU)

Yes, and the PSP has little to do with the BIOS, motherboard, or x86 CPU cores. By the time the CPU cores come out of reset and start running the BIOS, the PSP has already basically done all of it's work. It's not involved in microcode loading.

[Paradigm Shifter]

Well, I guess if another nasty security vulnerability lands, and AMD goes, "Aha! We aren't vulnerable!" and older microcodes are vulnerable... we'll know what the size jump was. Especially if the old vs. new microcode shows a performance hit (beyond 1-2%...)