AMD News Archives

This New Year's weekend brought the latest AMD patches working on plumbing the mainline Linux kernel with the hypervisor support around AMD Secure Nested Paging (SNP) as part of their Secure Encrypted Virtualization (SEV). SEV-SNP has been supported since EPYC 7003 series and while some elements of the support have been upstreamed for securing VMs, some bits remain.

One of the big milestones we are looking forward to in 2024 is the introduction of AMD Zen 5 processors. AMD Linux engineers have in recent months begun getting ready for those next-generation processors that look like will be Family 26 (1Ah) processors. We've been seeing more of the AMD "1Ah" patches and some more were posted today for some post-Christmas excitement before the new year.

As part of AMD's Platform Management Framework (PMF) and working on new Ryzen features like the Smart PC Solutions Builder, a set of patches are queued up ahead of the Linux 6.8 kernel cycle support for policy binary support with the PMF driver.

While the Linux 6.7 release is being pushed back by one week due to the holidays and in turn the Linux 6.8 merge window not officially opening until 8 January, some pull requests do end up getting submitted early. The 1-wire bus driver changes for Linux 6.8 were sent out this week and most notably includes adding the AMD AXI 1-wire host driver.

A quirk has been discovered with the AMD-powered Framework 13 inch laptop where if a user closes the laptop's lid on an already-suspended system, the system will wake up. A set of Linux kernel patches are on the way to workaround this issue.

A few months ago I wrote about AMD Linux engineers working on ACPI PHAT support for the Linux kernel. This week new patches around Linux ACPI PHAT handling have been posted with further confirmation of this functionality coming to "future" AMD SoCs.

Since earlier this year AMD has been working on Linux support for WBRF for mitigating WiFi radio frequency interference (RFI) with their latest Ryzen 7000 and forthcoming Ryzen 8000 series mobile processors. That work looks like it will be ready to land in Linux 6.8.

One of the latest Linux kernel patch series posted by AMD Linux engineers is for enabling an AMD QoS RMID pinning feature found within their latest generation processors.

For the past number of months AMD has been actively working on enabling AMD P-State Preferred Core functionality for Linux so that their modern processors can communicate "preferred" cores to the Linux kernel scheduler for making better decisions around task placement and ultimately ensuring best performance of Ryzen and EPYC processors running on Linux. This week they are up to their 11th take on these kernel patches.

Queued up into tip/tip.git's x86/cpu branch ahead of the Linux 6.8 merge window opening in a month is an optimization that should prove helpful in cloud/VM scenarios.

Narrowly missing the Linux 6.7 merge window that closed last week is the AMD 1-Wire "AXI" driver but it's now on tap for the Linux 6.8 kernel in the new year.

On 14 December is the previously-announced launch of 5th Gen Xeon Scalable "Emerald Rapids" and Intel Core Ultra "Meteor Lake" processors via a webcast from NASDAQ that Intel is promoting as the "AI Everywhere" event. AMD meanwhile recently announced an "Advancing AI" event for the week prior. While details on the AMD Advancing AI event are light, it's all the more interesting now with AMD teasing open standards and open-source around the event.

While there is now the 4th Gen EPYC processors with the exciting and vast line-up from the very powerful general purpose Genoa(X) processors and Bergamo for CSPs and very dense servers to Siena for telco/edge, the 3rd Gen EPYC "Milan(X)" processors remain very viable. Especially for those seeking to minimize hardware costs, seeking very mature platforms, or looking to upgrade existing EPYC SP3 servers, the EPYC 7003 series remains quite competitive. Today AMD formally announced six new Milan processors.

Back at the OCP Summit in Prague earlier this year AMD detailed openSIL for advancing open-source system firmware by opening up the CPU silicon initialization process. An update was provided at the OCP San Jose event in October around the AMD OpenSIL effort.

Going back to early last year saw AMD Linux engineers posting PerfMonV2 patches in preparation for Zen 4 processors. The PerfMonV2 updated performance monitoring capabilities with Zen 4 were merged last year and are supported with the latest EPYC 8004/9004 series processors. Coming only now though to Linux 6.7 is support for Unified Memory Controller (UMC) events as part of PerfMonV2.

Since the AMD Inception vulnerability was made public in August there were kernel patches merged that day and since then there's been a few rounds of clean-ups and fixes for this mitigation code formally known as the Speculative Return Stack Overflow (SRSO). With Linux 6.7, more SRSO mitigation clean-ups have been merged.

The x86/cpu changes for the Linux 6.7 kernel have been merged and is highlighted by a small but useful change for propagating of the AMD SVM virtualization feature flag to /proc/cpuinfo.

While there has already been various open-source Linux driver upstreaming work around the AMD Instinct MI300 series both for the MI300X GPU-only solution and the MI300A APU-based accelerator, for Linux 6.7 more work is happening.

While the Linux 6.6 kernel isn't set to be released until later today, over the weekend a number of early pull requests were submitted of new material for the Linux 6.7 merge window. Among those early PRs were for the Error Detection and Correction (EDAC) area of the kernel.

AMD today announced the release of HIP RT 2.1, the newest version of its HIP ray-tracing library for use by Blender and other software.

For those currently weighing between the (currently) nine different AMD Ryzen 7000 series processors for Linux use, here are fresh benchmarks of the Zen 4 desktop CPU line-up while testing with Ubuntu 23.10 and the Linux 6.5 kernel.

Since AMD's acquisition of Xilinx and working to broaden the portfolio of offerings for the data center, more AMD-Xilinx drivers have been working their way toward the mainline Linux kernel. There's been upstreaming efforts such as the Versal EDAC driver, generating DeviceTree nodes for PCI devices, Versal watchdog driver, QDMA driver, CDX bus support, and more. The latest driver working its way toward the mainline kernel from AMD is the AXI 1-wire driver.

With the newest AMD Ryzen 7040 series laptops there is "Ryzen AI" as a dedicated AI engine based on Xilinx IP to help accelerate machine learning with the likes of PyTorch and TensorFlow. Sadly though this Ryzen AI with their new Zen 4 laptops is only supported under Microsoft Windows at this point. But it could change with sufficient customer interest.

It was just over one week ago that AMD announced plans to acquire Nod.ai to enhance their open-source AI software capabilities. Today already they announced that acquisition has completed.

AMD today published a new CPU microcode revision for Family 19h processors, which include Zen 3 / Zen 3+ / Zen 4 processors. As is sadly standard, no change-log is provided.

AMD today posted a set of interesting patches for enabling better integration of their AMDKFD (Kernel Fusion Driver, what is their compute kernel driver) memory management with Linux's DRM GEM ioctl API. In turn the code allows managing virtual address (VA) mappings in compute VMs with the GEM_VA ioctl interface for greater control of buffers imported via DMA-BUF.

Over the past two weeks there has been a pleasant uptick in new commits to Coreboot as part of enabling EPYC 9004 "Genoa" series platform support.

AMD has published the Advanced Media Acceleration (AMA) v1.0 SDK as a software stack aimed for hardware video acceleration and capable of high density real-time transcoding. The AMD AMA SDK integrates with the likes of the open-source FFmpeg and GStreamer projects for fitting nicely in the Linux software ecosystem as well as sporting its own C-based API.

Merged today to Linux 6.6 Git is a new patch for fixing an AMD erratum CPU bug affecting Zen 4 based processors like the Ryzen 7000 series and EPYC 8004/9004 series.

It was just a few weeks ago that AMD acquired AI software company Mipsology to help their AI software efforts on FPGAs. Today AMD announced another notable AI software acquisition: open-source AI software vendor Nod.ai.

While the AMD P-State driver is working quite well for Ryzen systems already with the default on Linux 6.5, one of the additions we are still waiting to land is the AMD "Preferred Core" functionality. An eighth version of those patches were posted on Monday for inching this feature closer to the mainline kernel.

The upcoming Linux 6.7 merge window is set to include a new AMD driver for supporting error detection and correct (EDAC) for their Versal SoCs.

Earlier this year at the OCP Regional Summit in Prague AMD first presented openSIL as their new open-source CPU silicon initialization effort that can integrate with Coreboot and open-source boot firmware solutions. AMD openSIL is currently being prototyped on Genoa platforms but in a few years will eventually replace AGESA on both client and server processors. Later this month at the OCP Global Summit, there will be a new presentation on AMD openSIL.

A fix has made its way into the Linux PCI subsystem's power management branch to address various AMD Ryzen Rembrandt and Phoenix generation laptops failing to resume from suspend when external USB devices are attached for initiating the system resume.

As written about last month, AMD Linux engineers have been working on PMF Linux driver support for a "Smart PC Solutions Builder". The AMD Smart PC Solutions Builder feature is intended to provide OEMs with more control over system power/performance policies. It looks like systems making use of this feature are already to the marketplace or imminent with AMD having already landed the PMF firmware.

Checking for the presence of Intel virtualization (VMX) support and it being enabled can be easily achieved by looking at the flags in /proc/cpuinfo. But to this point AMD virtualization (SVM) has always been shown to user-space via /proc/cpuinfo even when the BIOS/platform has disabled SVM functionality. Finally for Linux 6.7 this oversight is being corrected.

The long ongoing saga of upstreaming AMD's Pensando Elba SoC support is now partially over with the initial enablement patches around the DeviceTree being queued as part of the SoC changes destined for the Linux 6.7 kernel cycle.

For a year and a half now Pensando has been working on enabling their Elba SoC support for the mainline Linux kernel - a process that coincidentally began just days after AMD announced it was acquiring Pensando. Over the past 18 months the AMD-Pensando Elba SoC enablement work has now been through 16 rounds of code review but still isn't over the finish line yet but some of the initial enablement code might finally land with Linux 6.7.

The AMD Platform Management Framework (PMF) Linux driver is preparing to support a new but potentially controversial feature that's seen little public information so far: the Smart PC Solutions Builder.

AMD's GPUOpen team today released a number of updated components for graphics application/engine developers.

AMD on Thursday released ZenDNN 4.1 as the newest release of their Zen Deep Neural Network Library for accelerating inference workloads on AMD Ryzen and EPYC processors. The ZenDNN library remains API compatible with Intel's oneDNN library and helps for building out optimized AI workloads for use on AMD Zen processors.

AMD announced today that their Versal HBM adaptive SoCs have entered production for these newest wares with high bandwidth memory.

Since early this year AMD has been working on Linux enablement patches for Dynamic Boost Control (DBC). This is a new feature of some AMD SoCs that allow an "authenticated entity" to have greater control over certain SoC characteristics to improve the power/performance. AMD DBC was merged for Linux 6.6 just days ago while already new patches have been posted that extend the supported platforms for this Dynamic Boost Control functionality.

AMD today published version 1.2 of their Unified Inference Frontend (UIF) that is for supporting deep learning inference across AMD CPUs, GPUs, as well as Versal adaptive SoCs and FPGAs. AMD UIF aims to accelerate AI inference across all AMD compute platforms with machine learning frameworks like PyTorch and TensorFlow. With UIF 1.2 adds initial support for Radeon GPUs.

On the AMD CPU side of the house, one of the patch series we are looking forward to seeing upstreamed in the Linux kernel is the AMD Preferred Core functionality that was initially sent out this summer. This AMD Preferred Core handling is built onto the AMD P-State driver and has been undergoing a few rounds of iteration with the latest "v5" patches having been posted this week.

AMD by way of their Xilinx acquisition has been running the Open Hardware Competition since 2015 for helping to drive new innovations around FPGAs and the ACAP compute platform. The winners of the AMD Open Hardware Competition 2023 were recently announced.

One of the patches to be picked up by the Linux 6.6 kernel this week brings back REP MOSQ for user-access on CPUs without Enhanced REP MOVSB (ERMS) support. In turn this can equate to some performance benefits on AMD CPUs lacking ERMS.

While I have been eagerly following the AMD openSIL project for open-source CPU initialization that will eventually replace AGESA, today AMD announced a new open-source firmware drop: the SEV firmware has been made open-source.

While we are eagerly awaiting ROCm support for more RDNA3 GPUs said to be coming later this calendar year, shipping Tuesday night was ROCm 5.6.1 as the newest point release for this open-source GPU compute stack.

Over the summer AMD Linux engineers began sending kernel patches for Family 1Ah (Family 26) processors that almost surely are for next-gen Zen 5 processors. Among the initial bits sent out for this next-generation AMD CPU Family are HWMON temperature monitoring and EDAC reporting, which are now on their way for the Linux 6.6 kernel.