Hi Evan,
On 27/07/16 15:24, Leif Lindholm wrote:
Graeme/Evan?
On 27 July 2016 at 10:58, Sudeep Holla sudeep.holla@arm.com wrote:
ACPI 6.0 introduced LPI(Low Power Idle) states that provides an alternate method to describe processor idle states.
LPI extensions leverages the processor container device(again introduced in ACPI 6.0) allowing to express which parts of the system are affected by a given LPI state. It defines the local power states for each node in a hierarchical processor topology. The OSPM can use _LPI object to select a local power state for each level of processor hierarchy in the system.
This patch adds LPI support on Juno.
Contributed-under: TianoCore Contribution Agreement 1.0 Cc: Ard Biesheuvel ard.biesheuvel@linaro.org Cc: Leif Lindholm leif.lindholm@linaro.org Signed-off-by: Sudeep Holla sudeep.holla@arm.com
Platforms/ARM/Juno/AcpiTables/Dsdt.asl | 232 ++++++++++++++++++++++++++++++--- 1 file changed, 213 insertions(+), 19 deletions(-)
Hi Lief,
The support in the kernel is now added(latest mainline as of today) and is enabled in defconfig. It's easy to test, just examine the sysfs entries:
/sys/devices/system/cpu/cpu*/cpuidle/state*/desc - Describes the cpuidle state /sys/devices/system/cpu/cpu*/cpuidle/state*/{usage,time} - Should keep ticking with time signifying that the idle states are entered and exited correctly
Any feedback on this ?