On Wed, 14 Jun 2023 at 08:43, Tushar Nimkar <quic_tnimkar@xxxxxxxxxxx> wrote: > > 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. Right. I am not saying it's the perfect solution, but it seems like it could potentially solve the problem for many cases. If you want some help to turn the cpuidle-psci driver into a loadable module, just reach out, I am happy to help. [...] Kind regards Uffe
