[coreboot] K8 and Fam10 CAR
c-d.hailfinger.devel.2006 at gmx.net
Mon Aug 11 13:51:25 CEST 2008
On 10.08.2008 23:36, Segher Boessenkool wrote:
>>> Don't APs also need to initialize DRAM? Or can the BSP do this
>>> "remotely" ?
>> APs should do it.
>> I'm getting a supermicro mainboard with 4 sockets and 128 GB memory,
>> and I want that done in parallel :-)
> In principle, the BSP can initialise multiple memory controllers
> in parallel as well. Using multiple processors to do it is quite
> hard, esp. since you cannot do "normal" SMP stuff because memory
> isn't initialised yet; and you get all the "normal" SMP headaches
> as well obviously.
> If the memory init needs to access resources that it cannot access
> remotely (like, MSRs on x86), you have no choice but to use APs,
> of course. This seems to be the case on FAM10h (but not on K8).
The AMD Family 0Fh BKDG says:
"The BSP must perform the following tasks: [...] Memory controller
initialization on all processor nodes"
The AMD Family 10h BKDG is silent on this.
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