On Thu, Oct 10, 2024 at 02:36:57PM -0500, Mario Limonciello wrote: > From: Perry Yuan <Perry.Yuan@xxxxxxx> > > The AMD Heterogeneous core design and Hardware Feedback Interface (HFI) > provide behavioral classification and a dynamically updated ranking table > for the scheduler to use when choosing cores for tasks. > > There are two CPU core types defined: `Classic Core` and `Dense Core`. > "Classic" cores are the standard performance cores, while "Dense" cores > are optimized for area and efficiency. > > Heterogeneous compute refers to CPU implementations that are comprised > of more than one architectural class, each with two capabilities. This > means each CPU reports two separate capabilities: "perf" and "eff". > > Each capability lists all core ranking numbers between 0 and 255, where > a higher number represents a higher capability. > > Heterogeneous systems can also extend to more than two architectural > classes. > > The purpose of the scheduling feedback mechanism is to provide information > to the operating system scheduler in real time, allowing the scheduler to > direct threads to the optimal core during task scheduling. > > All core ranking data are provided by the BIOS via a shared memory ranking > table, which the driver reads and uses to update core capabilities to the > scheduler. When the hardware updates the table, it generates a platform > interrupt to notify the OS to read the new ranking table. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 I tried to find the HFI details on the documents in this "bug" but I could not find them. What document in specific could I look at? Thanks and BR, Ricardo
