On 17 July 2015 at 20:03, Rafael J. Wysocki rjw@rjwysocki.net wrote:
On Saturday, July 18, 2015 02:01:40 AM Rafael J. Wysocki wrote:
On Thursday, July 09, 2015 02:04:18 PM Ashwin Chaugule wrote:
The ACPI processor driver is currently tied too closely to the ACPI P-states (PSS) and other related constructs for controlling CPU performance.
The newer ACPI specification (v5.1 onwards) introduces alternative methods to PSS. These new mechanisms are described within each ACPI Processor object and so they need to be scanned whenever a new Processor object is detected. This patch introduces a new Kconfig symbol to allow for finer configurability among the two options for controlling performance states. There is no change in functionality and the option is auto-selected by the architecture Kconfig files.
The following patchwork introduces CPPC: A newer method of controlling CPU performance. The OS is not expected to support CPPC and PSS at runtime. So the kconfig option lets us make these two mutually exclusive at compile time.
Signed-off-by: Ashwin Chaugule ashwin.chaugule@linaro.org
arch/x86/Kconfig | 1 + drivers/acpi/Kconfig | 19 ++++++--- drivers/acpi/Makefile | 6 +-- drivers/acpi/processor_driver.c | 86 +++++++++++++++++++++++++------------ drivers/cpufreq/Kconfig | 2 +- drivers/cpufreq/Kconfig.x86 | 2 + include/acpi/processor.h | 94 +++++++++++++++++++++++++++-------------- 7 files changed, 142 insertions(+), 68 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 226d569..93d150d 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -143,6 +143,7 @@ config X86 select ACPI_LEGACY_TABLES_LOOKUP if ACPI select X86_FEATURE_NAMES if PROC_FS select SRCU
- select ACPI_CPU_FREQ_PSS if ACPI
Also, does ia64 not use _PSS-based cpufreq?
True. Will add to the IA64 Kconfig.
Thanks, Ashwin.