topic Re: Local APIC questions,how can all local apics use the same base address to access their registers in Mobile and Desktop Processors

Local APIC questions,how can all local apics use the same base address to access their registers?

idata — Sun, 07 Jun 2009 04:34:58 GMT

APICs (both local and I/O) are memory mapped devices. The default location for the local APIC is at 0xfee00000 in physical memory. The local APIC will appear in the same place for each processor, but each processor will reference its own APIC。

how can all local apics use the same base address to access their respective registers?

If they use the same physical address, how can each processor reference their own registers like apic id register?

Re: Local APIC questions,how can all local apics use the same base address to access their registers?

HERBERT_H_Intel — Sun, 07 Jun 2009 07:13:57 GMT

http://wiki.osdev.org/APIC helps?

Re: Local APIC questions,how can all local apics use the same base address to access their registers?

idata — Sun, 07 Jun 2009 07:48:17 GMT

Thanks for your reply. I have read the article,but I did not find my answer.

It seems that all processsors can reference their respective local apic registers using the same physical address.

Re: Local APIC questions,how can all local apics use the same base address to access their registers

rainzhou — Wed, 20 Oct 2021 02:35:47 GMT

Hi idata,

Have you find the answer ? I am puzzled on this problem recently.Thank you.