[coreboot] PIC, APIC, XAPIC and XIOAPIC

Feng, Libo Libo.Feng at amd.com
Wed Mar 5 05:12:46 CET 2008


 
Hi, all,


I check the FILO code, all devices work under polling mode. So I think at the very beginning of initialization, OS probably needs the legacy PIC enabled before APIC mode enabled. 


Best Regards

??? Feng Libo @ AMD  Ext: 20906
Mobile Phone: 13683249071
Office Phone: 0086-010-62801406

-----Original Message-----
From: Segher Boessenkool [mailto:segher at kernel.crashing.org] 
Sent: Wednesday, March 05, 2008 4:10 AM
To: Feng, Libo
Cc: coreboot at coreboot.org
Subject: Re: [coreboot] PIC, APIC, XAPIC and XIOAPIC

> In LB stage, only PIC mode is applied, isn't it? However, I remember 
> some people of LB community told me there was no ISR except the debug 
> ISR during LB. So does this mean it totally unnecessary to setup PIC 
> via C00h/C001h IO port in LB?

You need to set up the legacy PIC really early, since it doesn't initialise itself to any sane settings at bootup.


Segher







More information about the coreboot mailing list