AMD News Archives

Sent out today as a fix for the Linux kernel's in-tree "cpupower" utility is properly handling P-State frequency reporting for upcoming AMD Zen 5 processors.

One of the patch series that sadly was not ready in time for the Linux 6.10 merge window and thus will need to wait a few months for at least the next kernel is enabling AMD Fast CPPC support for Zen 4 processors. Fast CPPC aims to allow the processor to deliver higher performance at the same power consumption.

As a follow-up to this morning's AMD EPYC 4004 review and benchmarks, Supermicro, ASRock Rack, Giga Computing, Tyan, and others have announced new motherboards/servers for these entry-level EPYC servers. In addition with the likes of ASRock Rack they have already published BIOS updates enabling existing AM5 Ryzen server boards to officially support the EPYC 4004 series processors.

As more positive indications around AMD's OpenSIL effort for open-source CPU silicon initialization to eventually replace AGESA, both AMD and Supermicro are now collaborating with the Open-Source Firmware Foundation. Supermicro has also publicly shown off a platform with OpenSIL+Coreboot and is said to be exploring OpenBMC for future hardware.

The recent AMD P-State Linux driver patches for heterogeneous core CPU topology, Fast CPPC, and Core Performance Boost haven't made it to the Linux power management's "-next" branch ahead of the imminent Linux 6.10 cycle. Thus it looks like those features won't be ready to make it for v6.10 unless by chance being deemed ready in the coming days and then sent in as part of a secondary set of merge window changes. However, some other AMD P-State fixes/improvements are queued up.

The Linux 6.9 kernel should debut as stable later today unless Linus Torvalds has second thoughts and decides to delay it by issuing a v6.9-rc8 kernel instead that would then push out the official release by an extra week. In any event, as a last-minute "x86/urgent" pull request is another Zen 5 PCI ID being added.

AMD last week sent out a set of patches to enhance the open-source FFmpeg multimedia library with integration around the AMD Advanced Media Framework (AMF). The AMF SDK allows for "optimal" access to AMD GPUs for multimedia processing but this patch series questioned the need in an era of Vulkan Video APIs beginning to see adoption.

Recently there was an LLVM bug report of "Worse runtime performance on Zen CPU when optimizing for Zen." Well, that's not good... Fortunately, that bug is now fixed with the latest LLVM Clang compiler code but other deficiencies in the AMD CPU optimization targeting remain.

A new patch series sent out today by AMD Linux engineers confirm that PCIe TPH will be supported with "upcoming AMD hardware" as a nice performance optimization feature for PCI Express.

AMD Linux engineers have introduced a new perf tool called "schedstat" that aims to be less resource intensive and convenient than the existing "perf sched" tool for profiling kernel scheduler behavior.

AMD engineers posted a new set of Linux driver patches on Tuesday that "addresses critical issues and enhances performance settings for CPUs with heterogeneous core types" while using the AMD P-State CPU frequency scaling driver.

For the past several months AMD Linux engineers have been working on AMD Core Performance Boost support for their P-State CPU frequency scaling driver. The ninth iteration of these patches were posted on Monday and besides the global enabling/disabling support for Core Performance Boost, it's now possible to selectively toggle the feature on a per-CPU core basis.

With the recently released Ubuntu 24.04 LTS I've shown various benchmarks how it can deliver nice performance gains over both Ubuntu 23.10 and the existing Ubuntu 22.04 LTS on different platforms. Those benchmarks have tended to focus on the latest-generation processors/platforms given that's where the excitement is these days. But for those on older platforms like AMD 3rd Gen EPYC "Milan" servers, here are some benchmarks looking at the performance impact of an Ubuntu 24.04 LTS upgrade.

An upcoming AMD micro-architecture (presumably Zen 5 given the timing and history around AMD's Linux hardware enablement...) is introducing Bus Lock Trap as a feature matching Intel's existing split/bus lock detection functionality.

While AMD Zen 4 processors whether it be the Ryzen 7000/8000 desktop/mobile series or EPYC 8004/9004 series server processors are already performing very well on Linux and with great power efficiency against the competition as shown in dozens of Phoronix articles at this point, it turns out there's been a minor power/performance optimization left untapped yet under Linux for select Zen 4 processors. A new patch series posted this Sunday allows for this "fast CPPC" feature to be utilized on supported processors.

As the last feature patch prior to the GCC 14 compiler code being branched today and GCC 15 opening up on the mainline codebase, AMD GFX90C support was merged for enabling GPU OpenMP device offloading to the numerous AMD SoCs/APUs with the GFX9/Vega graphics.

A new AMD Linux kernel patch queued today via "x86/urgent" for routing into the Linux 6.9 development kernel expands the range of recognized CPU model IDs for upcoming Zen 5 processors.

The AMD P-State CPU frequency scaling driver for Zen 2 and newer processors has been working out well in its roughly two years of being in the mainline Linux kernel. The AMD P-State driver has helped with ensuring modern Ryzen systems are delivering optimal performance and power efficiency. Recently AMD Linux engineers have been working on a few fixes and enhancements to this CPUFreq driver.

AMD's upstreaming effort around Secure Encrypted Virtualization Secure Nested Paging (SEV-SNP) to the mainline Linux kernel appears to be nearly wrapped up with the latest hypervisor patches now at their fourteenth revision.

AMD is using the Embedded World conference in Bavaria for today introducing their Versal Series Gen 2 SoCs for AI-driven embedded systems. Today's embargo lift covers the Versal AI Edge Series Gen 2 and Versal Prime Series Gen 2 Adaptive SoCs.

Following the launch last week of the AMD Ryzen Embedded 8000 Series, SolidRun today announced the Bedrock R8000 as the first industrial PCs designed around these new Ryzen Embedded 8000 series SoCs.

AMD today announced the Ryzen Embedded 8000 series processors -- their first AMD embedded chips to offer Ryzen AI with the onboard Neural Processing Unit (NPU). This AMD XDNA NPU support is similar to the existing Ryzen AI on the Ryzen 8000 series.

With the first quarter drawing to a close, here's a recap of the most exciting AMD Linux/open-source news from the quarter. During the past three months we've seen AMD finally publish their XDNA Linux driver for open-source Ryzen AI support, their open-source HDMI driver efforts were sadly rejected by the HDMI Forum, the AMD Zen 5 "znver5" compiler support was added to GCC 14, more AMD Zen 5 Linux kernel preparations made, and various other AMD Linux driver enhancements landed.

Disclosed last August was the AMD Inception vulnerability also known as SRSO for the Speculative Return Stack Overflow. The kernel-side patches for the AMD SRSO mitigation were quickly merged. Following that were more clean-ups and fixes to the SRSO mitigation code. It's been a quiet few months since while merged on Friday was fixing some of the mitigation code due to being ineffective.

While there is AOMP for OpenMP device offloading based on the LLVM/Clang compiler, less talked about and not as feature-rich is the AMDGCN back-end within the GNU Compiler Collection (GCC) that is also worked on for OpenMP device offloading capabilities to Radeon GPUs. Squeezing in for the upcoming GCC 14.1 stable release is GFX1103 support for AMD APUs with RDNA3 integrated graphics.

More AMD SEV-SNP bits are upstreamed now for the in-development Linux 6.9 kernel that is putting the EPYC processor support on the mainline kernel trajectory for "the ultimate goal of the AMD confidential computing side" to hopefully be in great shape come Linux 6.10 later in the year.

Back in February AMD posted GCC compiler enablement support for Zen 5 with the new "znver5" target ahead of launch. Since then it's been rather quiet and nervous not seeing this support merged ahead of the upcoming GCC 14 stable release, but this morning it's finally happened: the AMD Zen 5 processor enablement has been merged to GCC Git in time for the GCC 14.1 stable release that will be out in the coming weeks.

While AMD P-State driver's Preferred Core support was merged for Linux 6.9, another notable addition to this driver is still undergoing the patch review process: Core Performance Boost.

AMD's HIP Ray-Tracing library "HIP RT" has been one of the few projects under the GPUOpen umbrella that starts off as closed-source software but then is eventually open-sourced... That happened now with the HIP ray-tracing code becoming publicly available.

With the upgraded Linux kernel, compiler, and other software upgrades with next month's Ubuntu 24.04 LTS, those using recent AMD EPYC server processors like the 4th Gen EPYC Genoa(X) / Bergamo / Siena processors stand to benefit from greater performance over the current Ubuntu 22.04 LTS release.

An interesting anecdote was mentioned as part of the x86/misc changes queued for the Linux 6.9 kernel: on some unnamed AMD systems, NMI debug messages were too excessive that they actually slowed down the systems.

The in-development Linux 6.9 kernel is finally landing support for AMD Preferred Core as part of the power management updates for this mid-2024 kernel release.

While Linux 6.8 carries some elements of Zen 5 CPU support, more upstream Linux enablement for the next-generation AMD processors remains ongoing. Sent out this morning were the initial patches around AMD Zen 5 performance monitoring and events for the perf subsystem.

A number of x86-related pull requests were already submitted today for kicking off the new Linux 6.9 merge window. With the x86/cpu pull for this new kernel cycle there is just one patch and it's for slightly easing future AMD Zen processor enablement under Linux.

The AMD P-State CPU frequency scaling driver works with Zen 2 and newer processors supporting ACPI Collaborative Processor Performance Controls (CPPC) but to date this hasn't worked for Threadripper 3000 series processors with the TRX40 chipset. That though is finally being fixed up with Linux 6.9 thanks to a one-line code change.

AMD engineers and those debugging s2idle suspend/resume issues for Ryzen laptops under Linux will soon have more information at disposal for newer SoCs supporting MP2 STB functionality.

Queued for introduction in the upcoming Linux 6.9 kernel cycle is an FRU Memory Poison Manager "FMPM" developed by AMD that may later be adapted for other non-AMD platforms. The FRU Memory Poison Manager is working to persist information around known bad/faulty memory across reboots.

George Hotz with Tiny Corp that is working on Tinygrad and TinyBox for interesting developments in the open-source AI space has previously called out AMD over ROCm issues. Yesterday yielded new tweets by "the tiny corp" over AI training runs crashing with MES errors and then called for AMD open-sourcing the firmware to which AMD CEO Lisa Su has responded.

For those interested in FPGAs, AMD today unveiled the Spartan UltraScale+ FPGA product family with hardware coming in 2025.

As many enthusiasts wait to hear from AMD more broadly supporting ROCm in an official capacity across consumer Radeon GPUs and/or hearing about better supporting more Linux distributions outside of the major enterprise Linux distributions, today AMD announced a new medium for their communications with the community: the "New AMD ROCm Software Blog Platform" will be rolling out.

For the upcoming Linux 6.9 kernel cycle there are a number of AMD Instinct MI300 additions to the EDAC (Error Detection And Correction) and RAS (Reliability, Availability and Serviceability) drivers.

Making for a very exciting Saturday morning, AMD just posted their initial enablement patch for plumbing Zen 5 processor support "znver5" into the GNU Compiler Collection! With GCC 14 due to be released as stable in March~April as usual for the annual compiler release, it's been frustrating to see no Zen 5 support even while Intel has already been working on Clear Water Forest and Panther Lake support with already having upstreamed Sierra Forest, Granite Rapids, and other new CPU targets months ago... Well, Granite Rapids was added to GCC in late 2022. But squeezing in as what should now be merged in time is the initial AMD Zen 5 support!

Last year at FOSDEM 2023 there was a presentation on the state of AMD open-source firmware and since then a lot has changed from the AMD openSIL announcement to new platforms being in the process of being enabled. At FOSDEM 2024 this past weekend in Brussels was a fresh look at the current state of AMD open-source firmware.

The AMD ROCm Debugger "ROCgdb" is maintained as a fork of the GNU Debugger (GDB) with support added for the heterogeneous debugging of the ROCm compute platform. ROCgdb works well and is distributed as part of the ROCM stack. The good news is that AMD is also working on getting this AMDGPU/ROCm debug support added into the upstream GDB debugger.

More of AMD's Secure Encrypted Virtualization Secure Nested Paging (SEV-SNP) support for memory encrypted VMs is set to make it upstream for the Linux 6.9 kernel coming out toward the middle of the year.

Since last August AMD Linux engineers have been working on P-State Preferred Core support for the "amd_pstate" driver so that this functionality can be leveraged under Linux for improved task placement.

AMD on Wednesday evening released ROCm 6.0.2 as the newest point release to their open-source compute stack.

The AMD P-State CPU frequency scaling driver for improved thermal/power/performance behavior under Linux works for Zen 2 and newer systems where the platform exposes ACPI Collaborative Processor Performance Controls (CPPC) support. There's been a caveat though of the "amd_pstate" driver having issues for the Zen2-based Ryzen Threadripper 3000 series. With a newly-published set of patches, that issue should be resolved.

For AMD Zen 2 and newer systems making use of the modern AMD P-State driver on Linux for CPU frequency scaling, ACPI Collaborative Processor Performance Control (CPPC) interface is being used. For managing the ACPI CPPC energy performance preference (EPP), Intel's x86_energy_perf_policy utility is now being extended to AMD processors.

As I wrote about at the start of January, the open-source ATI Radeon R300 Linux graphics driver continues seeing new improvements even all these years later thanks to the open-source community. This wasn't some one-off work either in 2024 for this R300 to R500 GPU OpenGL driver but more work has since landed.