Subject: Re: What's difference between ARM_VECTORS_LOW and ARM_VECTORS_HIGH?
To: None <port-arm@netbsd.org>
From: Toru Nishimura <locore64@alkyltechnology.com>
List: port-arm
Date: 04/13/2007 13:39:27
Doug Brewer asks;

> Would you tell me what's diffrenece between ARM_VECTORS_LOW and
> ARM_VECTORS_HIGH?

It directs ARM core to take exception vector from base address 0x0 or
0xFFFF'0000.  Take a glance at CP15 Register 1 'V' bit definition.

> How do I know my machine use ARM_VECTORS_LOW or
> ARM_VECTORS_HIGH?

It looks, from the NetBSD stand point, arbitrary and insignificant to
assign exception vector vaddr to LOW or HIGH.

The reason why ARM designer offers this capability is unclear to me.

Toru Nishimura/ALKYL Technology