Thanks for response Ulf.
On 6/12/2023 3:56 PM, Ulf Hansson wrote:
On Thu, 8 Jun 2023 at 10:56, Tushar Nimkar <quic_tnimkar@xxxxxxxxxxx> wrote:
CPUidle already has CPUIDLE_FLAG_OFF to keep idle state disabled,
Lets extend the support to set this flag using device tree.
This allows to keep an idle state disabled and they can be enabled back using
sysfs after certain point using below command.
echo N > /sys/devices/system/cpu/cpuX/cpuidle/stateX/disable
This helps in cases where vendors want to keep cpuidle off until home
screen comes up. In the past attempt was done at [1] but it was not considered
safe option to export cpu_idle_poll_ctrl().
[1] https://patchwork.kernel.org/project/linux-arm-msm/patch/1637831676-32737-1-git-send-email-quic_mkshah@xxxxxxxxxxx/
Before considering this, I don't recall if I ever received a reply to
my earlier suggestion to the above thread. So, let me repeat my
question.
I am wondering if a similar improvement can be achieved by
modularizing the cpuidle-psci driver. If insmodding it after the
homescreen, we allow only ARM WFI during boot. This should achieve the
similar results as we get with $subject series, right?
[...]
This will not work for targets which does not have DLKM support.
Thanks,
Tushar Nimkar.
Tushar Nimkar (2):
dt-bindings: cpu: idle-states: Add idle-state-disabled property
cpuidle: dt: Add support to keep idle state disabled
Documentation/devicetree/bindings/cpu/idle-states.yaml | 8 ++++++++
drivers/cpuidle/dt_idle_states.c | 3 +++
2 files changed, 11 insertions(+)
Kind regards
Uffe
Thanks,
Tushar
