AMD News Archives

As a step toward further improving AMD laptop support under Linux, AMD engineers have been working on WiFi radio frequency interference (RFI) mitigation support for Linux with their latest laptops.

A new AMD open-source driver posted for code review that's aiming for the upstream Linux kernel is the QDMA driver.

With some basic additions to the amd64_edac Linux kernel driver, the Ryzen 7000 series desktop processors are being treated like the EPYC 9004 series for EDAC reporting, including ECC error reporting on supported RAM/motherboard configurations.

The AMD k10temp Linux driver is used for CPU temperature reporting with all modern AMD Ryzen/EPYC processors plus going back all the way to many earlier FX / Athlon / Sempron / Opteron / Phenom CPUs starting with the Family 10h line-up. While this driver has been in the Linux kernel for years, it's carried a limitation until now that it can't handle reporting negative temperatures. That is changing thanks to new patches from AMD.

AMD today announced the Ryzen 7020 C-series processors. These processors are interesting for at least having integrated RDNA2 graphics but are based on the aging Zen 2 architecture.

AMD engineers have been working out many quirks and oddities in system suspend/resume handling to make it more reliable on their hardware particularly around Ryzen laptops. In addition to suspend/resume reliability improvements and suspend-to-idle (s2idle) enhancements, one of their engineers also discovered an easy one-liner as a small step to speeding up system resume time.

The AMD EDAC Linux driver for Error Detection And Correction of AMD x86_64 CPU/memory errors is now being extended for handling AMD data center GPUs like the Instinct MI200 series and newer where any error reporting/correction information can now be propagated to this existing driver.

Sent out this morning were the x86/urgent patches for the Linux 6.4-rc2 kernel due for release later today. With the x86/urgent changes this week are just two AMD patches in preparing the kernel for Family 19h Model 78h processors.

Today was the big reveal of ASUS' ROG Ally with the specifications and pricing in full for this new gaming handheld that will be shipping on 13 June.

Sadly missing out on the Linux 6.4 kernel merge window by a few days is support for sensor monitoring with the ASUS ROG CROSSHAIR X670E Hero motherboard.

For those that haven't yet watched the AMD openSIL presentation from the OCP Regional Summit in Prague from April, the most interesting takeaway was deserving of its own article... AMD openSIL is planned to eventually replace the well known AGESA and that it will be supported across AMD's entire processor stack -- just not limited to EPYC server processors as some were initially concerned but will support all AMD processors.

Going back to mid-2022 AMD engineers have been working on Virtual NMI support with SVM for the Kernel-based Virtual Machine (KVM) as an efficiency optimization. With the in-development Linux 6.4 kernel the AMD VNMI support has been merged.

Going back to 2016 Intel began working on MIPI SoundWire support for Linux and now in 2023, AMD has joined the party with their initial AMD SoundWire support driver landing in the mainline kernel.

Back in March Framework Laptop announced an AMD Ryzen upgradeable laptop model but were initially light on details. Today they've revealed more information on this forthcoming product as well as opening up pre-orders.

One of the most exciting open-source software announcements so far this year has been around AMD openSIL for providing open-source CPU silicon initialization that works with the likes of Coreboot. The video from the AMD openSIL announcement in Prague is now available for those interested in learning more about this AMD open-source firmware effort.

Back in 2021 AMD began preparing Linux kernel support for 5-level paging support with their future processors and building off the prior 5-level page table kernel support established by Intel. That was followed by AMD enabling 5-level page table support with KVM SVM in the Linux 5.15 kernel. AMD CPUs with 5-level page table support since launched in the form of 4th Gen EPYC "Genoa" processors. One piece only now coming together though is AMD IOMMU driver support for 5-level guest page table support.

There's a bit of Linux kernel code for AMD Zen 2 processors called the "spectral chicken" and a call for cleaning up that code, which was originally written by an Intel Linux engineer, has been rejected.

As anticipated the AMD P-State driver extension building out the Guided Autonomous Mode of operation has been sent in as part of the CPU frequency scaling / power management changes for the in-development Linux 6.4 kernel.

A new patch series from AMD today for the Linux kernel enables Dynamic Boost Control support that can be found with some Ryzen SoCs for tuning the processor for optimal performance.

For weeks we have been eager to learn more about AMD openSIL that will formally be announced at the OCP Prague event later this week. In anticipation of that event, AMD last week revealed the initial details around this open-source firmware push.

AMD has released AOMP 17.0-1 as the newest version of this open-source compiler focused on providing the latest OpenMP offloading support for Radeon and Instinct accelerator products.

Open-source fans, rejoice, the most exciting thing I have read all week or perhaps the month: "AMD is committed to open-source software and is now expanding into the various firmware domains with the re-architecture of its x86 AGESA FW stack - designed with UEFI as the host firmware that prevented scaling, to other host firmware solutions such as coreboot, oreboot, FortiBIOS, Project Mu and others. A newer, open architecture that potentially allows for reduced attack surface, and perceivably infinite scalability is now available as a Proof-of-Concept, within the open-source community for evaluation, called the AMD openSIL – Open-Source Silicon Initialization Library."

AMD's Sensor Fusion Hub (SFH) driver with the upcoming Linux 6.4 cycle is being extended to support new Ambient Color Sensor "ACS" functionality.

Intel processors should have any CPU microcode updates loaded early during the Linux boot process to avoid various known issues. When "late loading" CPU microcode after the system is up and running, various issues can happen on Intel processors that led them to mark the Linux kernel as tainted under such conditions. Tainting the kernel also happened when late-loading microcode on AMD CPUs but now that's been deemed unnecessary and late-loading CPU microcode on AMD processors is reportedly safe.

For more than one year and now up to thirteen rounds of patch review, the AMD Pensando Elba SoC support continues in its trek toward the mainline Linux kernel.

Back in 2021 saw work on CPU cluster-aware scheduling by HiSilicon engineers for Arm processors as well as Intel engineers with a focus on their Jacobsville platform being comprised of clusters of Atom cores. That x86 cluster-aware scheduling was enabled for capable Intel processors while now two years later is being extended for AMD processors.

While AMD Zen 4 "Dragon Range" and "Phoenix" laptops are imminent, for those using an older AMD Picasso laptop design from 2019, there are some new Linux fixes on the way for enhancing that older Zen+ experience.

As I pointed out at the end of March, AMD has begun bringing up a new CDNA GPU in their Linux kernel driver code, past the currently known Instinct MI300 "GFX940" series. This "GFX943" part is some new CDNA multi-XCC accelerator and the open-source AMD engineers have begun posting many patches for this new GPU target. The initial bits of that support will appear in the upcoming Linux 6.4 cycle.

Since last year AMD-Xilinx has been posting Linux patches for enabling CDX as a new bus between application processors (APUs) and FPGAs. The AMD CDX bus is now poised for introduction in the upcoming Linux 6.4 cycle.

AMD today published HIP Ray-Tracing 2.0 "HIP RT" as the newest version of their open-source ray-tracing library built for use with their latest-generation GPUs for leveraging hardware ray-tracing capabilities.

AMD-Xilinx recently open-sourced their LLVM-based Nanotube compiler that can be used for some nifty networking purposes on FPGAs.

A change sent in this Sunday ahead of the Linux 6.3-rc3 release is a late addition adding a throttling mechanism to protect the hypervisor from potentially malicious AMD Secure Encrypted Virtualization (SEV) guests. The change is to protect the AMD Secure Processor from being potentially overloaded with requests by nefarious guest VMs.

While Linux 6.3 adds AMD P-State EPP as the "Energy Performance Preference" mode for enhancing the power/performance on recent Ryzen and EPYC systems on Linux, with Linux 6.4 the P-State Guided Autonomous Mode is coming to round out AMD's current CPU frequency scaling driver efforts.

AMD is using Embedded World 2023 in Nürnberg to launch the EPYC Embedded 9004 series as their 4th Gen EPYC processors intended for telecommunications, edge computing, automation, and IoT applications.

Following last night's Linux 6.3-rc2 release that brings a workaround for system stuttering on some AMD Ryzen systems, that workaround was quickly back-ported to the Linux 6.1 LTS and 6.2 stable series and spun into new releases for Monday morning.

Since the Linux 6.1 kernel various users have reported system stuttering issues when using modern AMD Ryzen systems. This has been similar to an "intermittent system stutter" issue AMD disclosed last year for Windows 10 and Windows 11 while now for today's Linux 6.3-rc2 a workaround is finally being merged that in turn will also be back-ported to the stable kernel series.

Sent in this morning via x86/urgent for integration into Linux 6.3 and also for back-porting to stable kernel series is disabling the XSAVES instruction for AMD Zen 1 and Zen 2 processors to workaround an AMD processor erratum made public last year.

On Thursday AMD engineers released AOMP 17.0-0 as the newest version of their LLVM/Clang downstream compiler that carries their latest development patches around Radeon/Instinct OpenMP GPU/accelerator offloading support.

Back in December initial AMD Zen 4 "znver4" support was merged for the LLVM/Clang 16 compiler. While the "-march=znver4" targeting at least flips on the newly-added AVX-512 instructions with these AMD processors, it was re-using the existing scheduler model from Zen 3. Finally today a tuned Zen 4 scheduler model has landed for what will be found in the LLVM 17 compiler later this year.

Last year AMD acquired Pensando in part for adding DPUs to their portfolio from this young company that only exited its stealth mode in 2019. While sadly it's missed out on the Linux 6.3 cycle, AMD-Pensando engineers continue work on upstreaming support for their "Elba" SoC into the mainline Linux kernel.

AMD in February quietly released version 1.1 of their in-development Unified Inference Front-end "UIF" that aims to be their catch-all solution for AI inference from CPUs to GPUs to FPGAs and other IP from their recent Xilinx acquisition.

If better open-source AMD Coreboot support was on your bingo card for years but long thought to be a lofty dream, get ready to celebrate... AMD dropped a juicy tid-bit of information to be announced next month with "openSIL" as it concerns open-source AMD x86 silicon initialization library, complete with AMD Coreboot support.

Going back to 2016 Intel began work on the SoundWire support for Linux, the MIPI standard started in 2014 to help consolidate audio interfaces between PC and mobile hardware. In preparation for seemingly new AMD hardware coming to market with SoundWire support, AMD engineers recently began working on an AMD SoundWire driver.

Adding to all of the other AMD changes coming with Linux 6.3 is now also having the AMD-Xilinx XDMA driver in tow. Getting this XDMA subsystem driver upstreamed is important for unblocking more Xilinx-based feature code to be merged into the Linux kernel.

AMD Slow Memory Bandwidth Allocation Enforcement as a new feature found with AMD EPYC 9004 series processors will be supported by the in-development Linux 6.3 kernel.

With the Linux 6.3 merge window opening up following tomorrow's stable debut of the Linux 6.2 kernel, there is a lot to be excited about if you are a customer of AMD's recent CPUs or GPUs.

Exposed via Linux's very versatile perf subsystem has been per-package energy monitoring via the RAPL (Run-Time Average Power Limiting) counters. But AMD's counters also support per-core energy monitoring and now with a tiny kernel patch those sensors too will be exposed via perf.

The ACPI, thermal, and power management changes for Linux 6.3 have been submitted early due to traveling next week by ACPI/PM maintainer Rafael Wysocki. Most significant with the Linux 6.3 power management updates is adding of the AMD P-State Energy Preference Performance (EPP) mode for helping to deliver better performance and power efficiency for modern AMD Ryzen and EPYC systems on Linux.

Last year AMD issued an advisory around "intermittent system stutter" when engaging the Firmware Trusted Platform Module "fTPM" with newer Ryzen systems running Windows 10 and Windows 11. While at first this only manifested on Windows, with Linux 6.1+ enabling the AMD fTPM RNG by default when present, this system stuttering issue has begun affecting Linux users too.

CVE-2022-27672 is being made public today as the "Cross-Thread Return Address Predictions" bug affecting various AMD and Hygon processors. This vulnerability affects the SMT mode where one sibling thread transitions out of the C0 state and the other sibling thread could use return target predictions.