Intel Bay Trail & Cherry Trail CPUs To Run Faster With Linux 4.1

While the big ACPI and power management changes were sent in more than one week ago for the Linux 4.1 kernel, another batch of ACPI/PM work was sent in this weekend. One of these last-minute changes should end up significantly benefiting the performance of modern Intel Atom Bay/Cherry Trail SoCs.

Of the few last minute ACPI/PM 4.1 changes is a tweak to the Intel P-State driver that changes the setpoint for Intel Atom hardware. With dropping the setpoint from 97 to 60, the P-State CPU frequency scaling driver will be much more aggressive in changing (increasing) the power/performance states when encountering load. Intel's Kristen Carlson Accardi says this change "improves performance on a variety of workloads with little power penalty." Unfortunately, no benchmarks were published, but I'll work on some new Bay Trail numbers once the Linux 4.1 kernel is further along.

This second ACPI/PM pull request for Linux 4.1 also adds Intel Skylake processor support to the RAPL power-capping driver.