Jetson-TK1 support for PSCI

Quoted 8 lines · Thierry Reding

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I also pushed my tree to gitorious:
https://gitorious.org/ijc/u-boot jetson-psci-v1

I would Ack your patch, but I don't think you've posted it and it has no S-o-b so that would seem a bit premature/rude of me. For the same reason I've not actually included it in the series posted (but it is in the gitorious branch).

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Feel free to take ownership of that patch. I currently don't have the time to work on this and it seems you've made good progress on it.

Will do. Could you offer a S-o-b for it please so I can pick it up.

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It could probably use some cleanup because there's a bit of debug output still in there. Also...

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FWIW I think you could drop your stub versions of psci_cpu_off and psci_cpu_suspend (assuming you don't want to implement them) since the common code has stubs.

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... I'd think you'd need to implement these so that you can get proper suspend/resume support in the kernel. I've had to disable cpuidle (via #undef CONFIG_PM_SLEEP in arch/arm/mach-tegra/cpuidle-tegra114.c) in the kernel to make that code not powergate CPUs. Ideally I think the kernel would check that it's running with PSCI support and disable the cpuidle driver. Maybe that could be done by introducing a new cpuidle driver that checks for PSCI availability and uses it when present.

Hrm, I'm not sure how this all fits together, it's not a problem I've noted before.

FWIW I think cpu_off and cpu_suspend are optional in PSCI v0.1 so an initial version doesn't necessarily need to implement them (sunxi doesn't for example), but as you say they do enable useful features.