[LinuxBIOS] x86_64: apic id lift patch

yhlu yhlu.kernel at gmail.com
Mon Nov 21 23:17:35 CET 2005


> Can you please explain clearly:
>
> - What are you changing.
1.  use core_vir instead of x86_max_cores, for E0 later single core,
core_vir could be 2, and x86_max_cores still is 1. So it makes node
calculation right.
2. not assuming that lifted apic id is continous. We can get exact
node id and core id from initial apicid.
> - What was the problem with the old behaviour
1. for E0 single core, node 2, initial apicid is 4, and old cold will
get node=4 instead of 2.
2. if the lifted apicid is not continous, it will assign strange node
id to the cpu.
> - Why that particular change
1. We can get exact node id and core id from initial apicid for E0 later.
> - Why can't that APIC number setup not be done by the BIOS itself
1. That patch the code more generic. and don't assume the lifted
apicid is continous.

Thanks

YH




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