On 1 December 2014 at 11:53, Ashwin Chaugule ashwin.chaugule@linaro.org wrote:
On 19 November 2014 at 15:36, Ashwin Chaugule ashwin.chaugule@linaro.org wrote:
CPPC (Collaborative Processor Performance Control) is defined in the ACPI 5.0+ spec. It is a method for controlling CPU performance on a continuous scale using performance feedback registers. In contrast to the legacy "pstate" scale which is discretized, and tied to CPU frequency, CPPC works off of an abstract continuous scale. This lets the platforms freely interpret the abstract unit and optimize it for power and performance given its knowledge of thermal budgets and other constraints.
The PID governor operates on similar concepts and can use CPPC semantics to acquire the information it needs. This information may be provided by various platforms via MSRs, CP15s or memory mapped registers. CPPC helps to wrap all these variations into a common framework.
This patch introduces CPPC using PID as its governor for CPU performance management.
Signed-off-by: Ashwin Chaugule ashwin.chaugule@linaro.org
drivers/cpufreq/Kconfig | 12 + drivers/cpufreq/Makefile | 1 + drivers/cpufreq/acpi_pid.c | 1156 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 1169 insertions(+) create mode 100644 drivers/cpufreq/acpi_pid.c
Ping.
Any comments on these patches?
Redirecting the Ping to Rafael/Dirk :)