AMD Hardware Feedback Interface for heterogeneous-core Ryzen CPUs
Support for AMD's Hardware Feedback Interface (ACPI device AMDI0104) on heterogeneous-core Ryzen processors, where the CPU reports per-core performance and efficiency hints so Linux can place workloads on the right type of core. It targets recent AMD client and embedded parts that mix core types, such as the Ryzen AI 300 laptops and Ryzen Embedded 8000 series.
recommendation
It should stay in the kernel because this is brand-new code, first posted in July 2025 and iterated through v2 later that summer, enabling a feature on current AMD silicon. AMD continues to ship heterogeneous-core parts such as the Ryzen AI 300 client chips and the newly announced Ryzen Embedded 8000 series, so the driver is the upstream path for good scheduling on those CPUs and has no replacement.
repository signals
sources
- lore.kernel.org
Initial 2025 upstream posting of the AMD heterogeneous-core/HFI driver series shows the driver is new and actively developed rather than obsolete.
- lore.kernel.org
A v2 repost of the same 2025 series indicates active review iteration, not abandonment or removal planning.
- amd.com
AMD was marketing Ryzen AI 300 series client processors in 2025; these are current products in the timeframe relevant to heterogeneous-core scheduling support.
- amd.com
AMD announced Ryzen Embedded 8000 series in 2026, supporting the inference that heterogeneous-core AMD client/embedded platforms remain in new deployments beyond 2025.
codex reasoning notes (technical)
Local shell inspection of drivers/platform/x86/amd/hfi/{Kconfig,hfi.c} shows a 2025 AMD platform driver for ACPI ID AMDI0104, gated on AMD heterogeneous-core/workload-class CPU features. Lore evidence was obtained via web search and clicking through Phoronix-linked lore threads to the v1 and v2 patch series URLs; these show creation and active review in mid-2025, with no sign of removal discussion. AMD product/press URLs were obtained via web search and indicate relevant AMD heterogeneous-core client/embedded hardware is still being sold and introduced after 2025. This looks like a current enablement driver for new AMD platforms, with niche but real deployment, and no natural replacement driver.