AMD News Archives

While Linux 6.0 won't be out for another month and a half, on deck already for Linux 6.1 is the AMD Platform Management Framework "PMF" driver being queued into platform-drivers-x86.git.

Up to this point loading updated CPU microcode on AMD processors under Linux has checked just to ensure every physical CPU core was loaded with the new microcode but not sibling threads for SMT processors. While logically that makes sense, it turns out some AMD microcode updates do carry out per-thread modifications that means the microcode updating needs to be carried out on every thread. A Linux fix is on its way to the kernel to adjust that behavior.

AMD today sent out revised patches for improving the AMD P-State CPU frequency scaling Linux driver that aims to provide better power efficiency than the generic ACPI CPUFreq driver that has long been relied upon for AMD processors.

Sent out this morning is a Linux kernel "fix" that now enabled STIBP when using the IBPB mode for Retbleed mitigations on AMD processors. In other words, more protections needed for this enhanced mode of Retbleed mitigation.

The colorful fishy codenames are not over for AMD's Linux driver crew! While on the GPU side they have moved to IP block-by-block enablement strategy for their future GPUs, over on the audio co-processor side AMD posted a series of patches today under the "Pink Sardine" codename.

While all of the key Zen 4 CPU functionality appears in place for the mainline Linux kernel, AMD engineers continue working to enable other new Zen 4 features for use under Linux. The newest patches out of AMD this morning are for LbrExtV2.

With AMD EPYC showing some nice gains on Linux 6.0, I've been eager to begin testing Linux 6.0 on more systems especially now that the v6.0 merge window is winding down... With now having the shiny new AMD Ryzen Threadripper 5965WX, I decided to take this high-end 24-core chip for a run with Linux 6.0 Git to see how it performs over Linux 5.19 stable.

In addition to Intel's busy Patch Tuesday, AMD today made public CVE-2021-46778 that university researchers have dubbed the "SQUIP" attack as a side channel vulnerability affecting the execution unit scheduler across Zen 1/2/3 processors.

AMD engineers have released an updated version of AOMP, their LLVM/Clang downstream that carries the company's latest patches around OpenMP offloading to Radeon GPUs.

AMD Automatic Mode Transition (AMT) is a new feature wired up for Ryzen-powered ThinkPad laptops that is being introduced with the Linux 6.0 kernel.

You may recall the Phoronix news earlier this year around an AMD "Sabrina" SoC appearing in Coreboot for open-source system firmware support. Over the past few months we've cited a number of AMD Sabrina hits in open-source code but outside of that haven't heard much else about "Sabrina" or seen it on AMD's roadmaps.

Earlier this year AMD began posting Linux kernel patches for >a href="https://www.phoronix.com/news/AMD-Zen-4-IBS-Linux">Instruction Based Sampling (IBS) extensions coming with Zen 4 processors. With Linux 5.19 the Zen 4 IBS extensions landed while now with Linux 6.0 the perf tools have been updated for dealing with Zen 4 IBS.

With Linux 6.0 having some big scheduler changes and tuning that should specifically benefit AMD Zen systems, I've been eager to see how some high core count EPYC servers will benefit from this next version of the Linux kernel. While just a few days into the Linux 6.0 merge window, here are some early benchmarks showing some of the areas where Linux 6.0 is allowing higher performance out of existing AMD EPYC 7003 series hardware.

AMD recently started posting Linux patches for a Platform Management Framework "PMF" driver that is designed to "enhance end user experience by making AMD PCs smarter, quieter, power efficient by adapting to user behavior and environment."

Some of the newest Linux patches out of AMD for new processors are implementing support for some recently-documented Quality of Service extensions: L3SBE and BMEC.

Among the early pull requests for the now-open Linux 6.0 merge window (nee Linux 5.20) are a few AMD additions worth mentioning.

The newest AMD Linux optimization patch for the kernel aims to introduce a cool down period for the AMD Platform Security Processor (PSP) after each I2C transaction between the x86 CPU and the PSP.

With the upcoming Linux 5.20 cycle is support for AMD's Sensor Fusion Hub v1.1 revision being found in newer Ryzen laptops.

AMD today posted new open-source Linux driver code for enabling the audio co-processor (ACP) with the upcoming Raphael platform with the Ryzen 7000 series processors.

Last week AMD quietly released AOCL 3.2 as the newest version of their optimized CPU software libraries for use across Ryzen, Ryzen Threadripper, and EPYC platforms.

Following some weekend benchmarks here are more complementary numbers on the Retbleed mitigation performance benchmark costs. These additional numbers are on a Zen 2 based AMD Ryzen 7 4800U APU that has been common both to laptops as well as embedded/low-profile devices for thin client computing, IoT / edge use-cases, and more.

Back in Linux 5.17 the AMD P-State "amd_pstate" driver was introduced for Ryzen and EPYC systems as an alternative to the ACPU CPUFreq frequency scaling driver with an emphasis on delivering better power efficiency for modern AMD Zen 2 and newer systems. Since the mainlining there hasn't been too much change to this driver but now a new patch series has been sent out with some updates.

It's great seeing AMD continuing to hire for more Linux/open-source driver developers. Beyond their many roles they are still working to fill on the CPU side of the house, they have a new job posting in hiring for their open-source GPU driver stack with a focus on multimedia efforts.

Today's Coreboot code now has AMD Rembrandt SoC support by splitting it out from the Sabrina SoC support that has been in the works the past several months for this open-source firmware project.

Somewhat surprisingly, AMD engineers have been working on some new Linux kernel patches for their aging Jadeite platform.

After AMD announced FidelityFX Super Resolution 2.0 back in March, as of today they have made good on their word to open-source it.

AMD is using the Embedded World conference in Nürnberg to launch the Ryzen Embedded R2000 series for industrial use-cases along with IoT, thin clients, and edge computing.

After announcing the Threadripper PRO 5000 WX series back in March and with Lenovo being their launch partner for these Zen 3 Ryzen Threadripper CPUs, AMD today shared an update on availability.

Earlier this year Pensando engineers began posting Linux patches for enabling their Elba DPU SoC. This data processing unit is powered by 16 x Arm Cortex-A72 cores and designed for supporting up to dual 200GE networking with this SoC intended for high-end networking equipment. It didn't take long for the AMD integration less than one month after AMD completed its Pensando acquisition with the new Linux patches now reflected as the AMD Pensando Elba.

One of my personal gripes with AMD's Zen CPU support on Linux has been the lack of timely support for CPU temperature monitoring with their "k10temp" driver. Even though usually just new IDs are often needed and sometimes needing to adjust offsets or other minor changes, it has traditionally been done post-launch and sometimes left up to patches from the open-source community. Thankfully that has been changing and with Zen 4 it looks like that support will be ready for launch-day with the mainline Linux kernel.

While not record-shattering like the 1.1 Exaflops Frontier supercomputer at ORNL that took the Top500 spot this year from Fugaku, LUMI was inaugurated today with the claim of Europe's most powerful supercomputer.

A patch from AMD to further tune the Linux kernel's scheduler around NUMA imbalancing has been queued up and slated for introduction in Linux 5.20. For some workloads this scheduler tuning can help out significantly for AMD Zen-based systems and even on Intel Xeon servers has the possibility of helping too.

AMD today hosted their 2022 Financial Analyst Day where they made some new disclosures and firmed up past product road-map plans.

Earlier this year was an AMD Linux patch to prefer using MWAIT rather than HALT for cases where the CPU idle driver isn't being used. Using MWAIT can lead to significant improvements for the exit latency and now for the Linux 5.20 cycle later this year that change is expected to land.

A new patch series posted today by AMD is enabling peer-to-peer support within their AMDKFD kernel compute driver for allowing communication between multiple AMD GPUs over the PCIe bus without needing intermediate copies through system memory. In turn this should help with the multi-GPU compute performance for the Radeon ROCm stack.

It appears that with upcoming AMD Zen 4 processors there will finally be Virtual NMI (VNMI) support for virtualization, a feature Intel CPUs have supported for well more than the past decade.

It was just last month that AMD announced plans to acquire Pensando and today that $1.9 billion deal has been completed.

Last year with the launch of AMD EPYC 7003 "Milan" processors one of the new security features was SEV-SNP, or the "Secure Nested Paging" update to the Secure Encrypted Virtualization functionality that has built up with succeeding EPYC generations. While AMD published out-of-tree kernel patches in a GitHub repository to enable SEV-SNP and has been volleying several revisions to them on the kernel mailing list, one year later it's finally arriving in mainline with the Linux 5.19 kernel.

AMD CEO Lisa Su keynoted this morning for Computex 2022 where she talked up some of the company's processor plans for the rest of the year. The focal points were on the much anticipated Ryzen 7000 series desktop processors as well as announcing the "Mendocino" APUs that will be coming to affordable laptops later in the year.

AMD on Tuesday released the Kria KR260 Robotics Starter Kit featuring a Xilinx Kria K26 System-on-Module and tailoring it for robotics, machine vision, and industrial communication/control use-cases while running Ubuntu 22.04 LTS.

For over the past year we've seen various patches posted by AMD engineers with a state effort around preparations for the Frontier supercomputer. Most of these patches have involved memory handling under Linux and the special purpose memory handling between the CPU/GPUs. Published on Monday was their latest work on coherent device memory mappings for the Linux kernel.

The AMD-owned Xilinx posted a new patch series today implementing a new DRM display driver for supporting their soft MIPI DSI Tx subsystem IP.

Last month an AMD engineer began posting Linux kernel patches so the kernel prefers the MWAIT instruction over HALT for lowering the CPU idle exit latency. Preferring MWAIT over HALT has been something Intel CPUs on Linux have preferred going back to the Core 2 days and indeed with modern AMD CPUs there is significant advantages to lowering the exit latency in doing so for the idle code. This morning the latest iteration of the work was posted.

Upcoming AMD Zen 4 processors are bringing improvements to their Instruction-Based Sampling (IBS) capabilities that can be utilized by Linux's wonderful perf utility and subsystem.

Going along with many recent s2idle (suspend to idle) fixes as well as other fixes/workarounds/improvements like around S0ix, a patch is pending as a fix/workaround to get s2idle behaving correctly -- or rather, more timely -- on more AMD Ryzen powered Lenovo laptops.

Following AMD completing its Xilinx acquisition back in February, AMD is now preparing to ramp up their investment into embedded Linux. AMD is hiring for the "creation and maintenance" of a Yocto-based Embedded Linux platform for running on Xilinx SoCs.

Merged in Linux 5.18 is the AMD HSMP driver for enabling the "Host System Management Port" usage under Linux as an interface for enabling additional system management functionality on AMD EPYC 7003 servers. For Linux 5.19 this AMD HSMP driver is set to be extended with additional features coming with next-generation AMD EPYC servers.

AMD continues working on their open-source Linux driver support for next-gen GPUs... The latest patches posted on Friday are for "GFX11", pointing to the major new graphics IP version with RDNA3 graphics processors due out later this year.

Lawrence Livermore National Laboratory now has their Kripke software ported to running on AMD's HIP for GPU acceleration.

AMD's open-source Linux engineers on the CPU side of the house continue being quite busy with all sorts of new feature enablement work, which given their timing and other factors is almost all definitively for upcoming Zen 4. AMD this week sent out updated patches in getting "PerfMonV2" support in order that is updated performance monitoring abilities with upcoming processors.