AMD confirms low-power CPU core inclusion in next-generation Zen 6 processors for energy efficiency.

AMD has submitted Linux kernel patches that add support for new low-power CPU cores expected to appear in its future heterogeneous processors. The patches introduce explicit classification for three core types: high-performance, efficiency, and low-power cores, each optimized for different workload profiles.

AMD's heterogeneous processors identify CPU types using CPUID Function 0x80000026 (Extended CPU Topology), with EBX bits [31:28] carrying the core classification. Previously, AMD only classified cores as Performance or Efficiency; the latest patch adds Low-Power cores to this taxonomy. The update enables Linux to properly distinguish between all three core types and ensures they are correctly managed by AMD's performance management subsystem.

According to AMD engineer Vishal Badole, these low-power cores are specifically designed for background and idle tasks where energy efficiency takes priority over raw performance.

Both AMD and Intel have increasingly adopted heterogeneous processor designs in recent years, combining high-performance cores with energy-efficient alternatives. Intel's latest CPU platforms include low-power cores housed in a separate SoC tile to handle light workloads and extend laptop battery life. AMD is pursuing a similar strategy, though the two companies differ in their architectural approach. AMD maintains the same underlying architecture across core types with density optimizations and different clock speeds, whereas Intel uses entirely different microarchitectures for each core type.

AMD has disclosed limited details beyond the kernel patches. The company describes the low-power cores as optimized for minimal power consumption during background processing and idle operation but has not revealed how they differ architecturally from today's Zen 5c cores. The kernel patches introduce no new scheduling policies or optimization logic beyond identifying the additional CPU category.

AMD has not specified whether these cores will be based on Zen 5, Zen 6, or a later microarchitecture. AMD has traditionally preferred to use the same microarchitecture within a single processor, applying different optimizations to die size and clock speeds rather than fundamentally different designs. This approach simplifies software development and performance management but results in higher power consumption compared to what simplified microarchitectures might achieve.