> 
> There are no PEI module changes in this patch series.
> 
> So where does the HOB come from?
> 

Who use, who produce. Here, just provide the interface capability.   

> And what are the reasons for setting SMBASE in a PEI module instead
> of PiSmmCpuDxeSmm?
> 

Do the smbase relocated ahead of SMM cpu driver can bring the benefit as I 
explain in the patch 2:

PiSmmCpuDxeSmm will retrieve the SMBASE addresses from SMM Base Hob
and installs the SMI handler at [SMBASE+8000h] for each processor
instead of relocating SMM Base addresses from SMRAM again.

With SMM Base Hob, PiSmmCpuDxeSmm does not need the RSM
instruction to reload the SMBASE register with the new allocated
SMBASE each time when it exits SMM. SMBASE Register for each
processors have already been programmed and all SMBASE address
have recorded in SMM Base Hob. So the same default SMBASE Address
(0x30000) will not be used, thus the CPUs over-writing
each other's SMM Save State Area will not happen. This way makes
the first SMI init can be executed in parallel and save boot
time on multi-core system.


> take care,
>   Gerd



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