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
config INSTRUCTION_DECODER def_bool y diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index ab2cbb5..00748dc 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -166,17 +166,26 @@ config ACPI_DOCK This driver supports ACPI-controlled docking stations and removable drive bays such as the IBM Ultrabay and the Dell Module Bay. +config ACPI_CPU_FREQ_PSS
- bool
- depends on ACPI_PROCESSOR && CPU_FREQ
- select THERMAL
- help
This driver implements ACPI methods for controlling CPU performanceusing PSS methods as described in the ACPI spec. It also enables supportfor ACPI based performance throttling (TSS) and ACPI based thermalmonitoring. It is required by several flavors of cpufreqperformance-state drivers.
So are you not agreeing with what I've said for a few times already or are you just not listening?
This option should *not* be user-selectable. So please drop the help part and make it look like ACPI_SLEEP, for example.
Thanks, Rafael