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From: "Måns Rullgård" <mans@mansr.com>
To: linux-mips@linux-mips.org
Subject: fast_iob() vs PHYS_OFFSET
Date: Fri, 28 Nov 2014 23:50:16 +0000	[thread overview]
Message-ID: <yw1xsih2evgn.fsf@unicorn.mansr.com> (raw)

I'm a little confused over the interaction between fast_iob() and
non-zero PHYS_OFFSET.

The __fast_iob() macro performs a load from CKSEG1.  AFAICT, CKSEG1 is
always (on 32-bit systems) defined to 0xa0000000.  In case of a non-zero
PHYS_OFFSET, this address might not map to anything in particular, and
almost certainly not RAM.  There is a special case for IP28, but this is
not the only system with an unusual address map.

What am I missing?

-- 
Måns Rullgård
mans@mansr.com

             reply	other threads:[~2014-11-28 23:50 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-28 23:50 Måns Rullgård [this message]
     [not found] ` <Pine.LNX.4.64.1411300255520.2113@Opal.Peter>
2014-11-30 12:20   ` fast_iob() vs PHYS_OFFSET Måns Rullgård
2014-12-01  1:29     ` peter fuerst
2014-12-01  1:30       ` Måns Rullgård
2014-12-01 10:41     ` Thomas Bogendoerfer
2014-12-01 13:37       ` Måns Rullgård
2015-01-11  4:43         ` Maciej W. Rozycki

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