On Mon, Jun 09, 2014 at 06:03:31PM +0100, Doug Anderson wrote: [...] > Cold boot and resume from suspend are detected via various special > flags in various special locations. Resume from suspend looks at > INFORM1 (0x10048004) for flags. This register is 0 during a cold boot > and has special values set by the kernel at resume time. > > It also looks as if some code looks at 0x10040900 (PMU_SPARE0) to help > tell initial cold boot and secondary CPU bringup. Ok, thanks a lot. It looks like firmware paths should be ready to detect cold vs warm boot, and hopefully do not rely on a specific MPIDR to come up first out of power states. > > I am asking to check if on this platform CPUidle (where the notion of > > primary CPU disappears) has a chance to run properly. > > I believe it should be possible, but we don't have CPUidle implemented > in our current system. Abhilash may be able to comment more. I am interested in more insights, that's very helpful thanks. > > Probably CPUidle won't attain idle states where IRAM content is lost, but I > > am still worried about the primary vs secondaries firmware boot behaviour. > > I don't think iRAM can be turned off for CPUidle. It might be added a system state but I doubt that too and if you are relying on registers for jump addresses that's not even a problem in the first place. > > What happens on reboot from suspend to RAM (or to put it differently, > > what does secure firmware do on reboot from suspend to RAM - in > > particular how is the "jump" address to bootloader/kernel set ?) > > Should be described above now. Thank you very much. Lorenzo -- 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
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