Re: apic in 2.3.99-pre6

From: Frank Mehnert (fm3@os.inf.tu-dresden.de)
Date: Thu Apr 27 2000 - 08:59:51 EST


On Thu, 27 Apr 2000, Gerard Sharp wrote:

> I get the impression I don't really have an APIC (not surprising since it's a
> uniprocessor board :) )
> but then, on boot, it pretty clearly states
>
> Apr 28 01:42:50 midnight kernel: mapped APIC to ffffe000 (01242000)

As far as I know the APIC is disabled on most Uniprocessor Boards.
I have an Athlon 700 MHz Model 2 on a K7M Mainboard, which have an
APIC (see docs), but cat /proc/cpuinfo does not show this feature.

The APIC can be enabled by writing a machine status register (MSR 0x1B
bit 0xb). After enabling the APIC, it emulates an i8259 and has to
be programmed correct to get interrupts.

Frank

-- 
Frank Mehnert
## Dept. of Computer Science, Dresden University of Technology, Germany ##
## E-Mail: fm3@os.inf.tu-dresden.de    http://os.inf.tu-dresden.de/~fm3 ##

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sun Apr 30 2000 - 21:00:13 EST