Hi Doug, On Tue, Jun 10, 2014 at 9:19 PM, Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> wrote: > On Tue, 10 Jun 2014, Doug Anderson wrote: > >> My S-state knowledge is not strong, but I believe that Lorenzo's >> questions matter if we're using S2 for CPUidle (where we actually turn >> off power and hot unplug CPUs) but not when we're using S1 for CPUidle >> (where we just enter WFI/WFE). >> No Its not plain WFI. All cores in Exynos5420 can be powered off independently. This functionality has been tested. Below is the link for the posted patches. https://lkml.org/lkml/2014/6/10/194 And as Nicolas wrote, these patches need MCPM for that. >> I believe that in ChromeOS we use S1 CPUidle and that it works fine. >> We've never implemented S2 that I'm aware of. > > You'll have to rely on MCPM for that. That's probably why it hasn't > been implemented before. > > > Nicolas > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html