[coreboot] AMD AP core startup problem

[Scott Duplichan]

Hello,

I find with my RS780/SB700 board (ECS A780GM-M3), the initial
family 10h AP launch is not reliable. I often see a hang when
when all the cores are running in parallel. The parallel execution
is apparent if serial logging is enabled, because the characters
logged by each core are interleaved. I noticed the AP cores do a
few cf8/cfc pci config writes. Could simultaneous access to this
shared index/data pair be responsible for the hang? Concerns about
such conflicts is why the AMD agesa code does not run cores on the
same die in parallel.

Thanks,
Scott