omap4-panda-es boot issues with v3.15-rc4

[Kevin Hilman]

Tony Lindgren <tony at atomide.com> writes:

[...]

> ..but I think I found the cause for recent hangs on panda, just a wild
> guess based on looking at the recent cpuidle patches after v3.14.
>
> Looks like reverting 0b89e9aa2856 (cpuidle: delay enabling interrupts
> until all coupled CPUs leave idle) makes booting work reliably again
> on panda.
>
> Can you guys confirm, so far no issues here after few boot tests,
> but it might be too early to tell.

Reverting that makes things a bit more stable, but it still eventually
fails in the same way.  For me it took 8 boots for it to eventually
fail.

However, if I build with CONFIG_CPU_IDLE=n, it becomes much more stable
(20+ boots in a row and still going.)

Kevin