On Tue, Jul 3, 2018 at 11:36 PM, Sricharan R <sricharan@xxxxxxxxxxxxxx> wrote: > Hi Andy, > >> >> That said, the current code mach-qcom/platsmp.c does not implement the >> cpu_kill callback. Even for a hotplug its just a wfi(). While doing >> a wfi() is going to work for hotplug, it would not for the kexec, since >> the cpu's were never put it reset state and waking them would simply fail. >> >> That means we need to have the complement to kpssv2_release_secondary >> implemented for cpu_kill callback. I will try to write down the exact >> sequence from programming guide and give here. >> > > Please look at the code in drivers/soc/qcom/spm.c that controls the sequence > of cpu 'c' state during the cpuidle. spm block is the one that takes care > of powerdown/up sequence of the cpu after 'wfi' . Similar thing needs to be > then done for cpu_kill if we expect a 'cpu' to be powercollapsed and to > be brought back during the kexec kernel reboot. > > Also, please have a look at > https://source.codeaurora.org/quic/la/kernel/msm-4.4/tree/arch/arm/mach-msm/platsmp.c?h=LA.HB.1.1.5.c1, > old non-dt code that is having the cpu_kill back. When no PM, it simply is a WFI. > > Regards, > Sricharan > > -- > "QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation Hi Sricharan, I just want to thank you for your help and suggestions. I wasn't able to get it working quickly, so I have to move on to other things. If/when I get this working, I'll be sure to let you know what I did. Thanks, Andy -- http://www.uplevelsystems.com <http://www.uplevelsystems.com> -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
