[coreboot] Questions about more AMD related flags

xdrudis xdrudis at tinet.cat
Sun Nov 7 02:02:48 CET 2010

On Sat, Nov 06, 2010 at 03:32:30PM +0100, xdrudis wrote:

> So I would suppose you don't really need to check all cores in 
> a processor. If they share the northbridge how could they
> require different frequencies for it ?. But this is only with
> respect to the frecuency. Maybe you want to wait for all simply
> to make sure you already set the NBVid before you set the NbFid?
> I believe for tilapia_fam10 you already have waited 
> at wait_all_other_cores_started  before calling init_fidvid_bsp,
> so you could have SET_FIDVID_CORE_RANGE to 1 and save a little.

Sorry, I was mistaken. wait_all_other_cores_started does not mean
wait for all cores that have started (until they're done) 
but wait for all cores to start. I mean that 
wait_all_other_cores_started waits
until cores have written  F10_APSTATE_STARTED to the lapic and 
init_fidvid_bsp waits until they have written F10_APSTATE_RESET,
just after seting nbvid an changing to pstate 1 and then core0 to pstate 0

I'm not 100% that BKDG requires synchronization
after each step, which we don't do, but if it is required between
steps 6 and 8 then SET_FIDVID_CORE_RANGE can't be set to 1
because we wouldn't be waiting for all cores to change to p1.

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