Subject: Re: Can I access ISA bus and PGIO pins through /dev/mem?
To: Anders Lindgren <email@example.com>
From: Steve Woodford <firstname.lastname@example.org>
Date: 06/15/2007 21:51:23
On Tuesday 12 June 2007 00:41:30 Anders Lindgren wrote:
> On Mon, 11 Jun 2007, Jesse Off wrote:
> > Not quite. I believe the ARM pmap module (pmap_enter()) will
> > assume any physical address not explicitly registered with
> > uvm_physload() is uncacheable/unbufferable.
> .oO( Out of curiosity -- does this imply that it doesn't even keep
> track of what physical address regions are defined at all, for a
> given architecture? I.e. would mmap of an unused chip select area
> succeed, and silently read as bus garbage? )
Correct. The pmap code has no knowledge of a platform's memory map. The
onus is on its callers to know what they're doing.