Re: [Linux-fbdev-devel] Re: fbcon slowness [was NTP on 2.4.2?]

Maciej W. Rozycki (macro@ds2.pg.gda.pl)
Fri, 6 Apr 2001 19:27:24 +0200 (MET DST)


On 6 Apr 2001, Eric W. Biederman wrote:

> I recall on the ev6 all memory accesses to locations with bit 40 set
> are always to IO space are never cached and are never write buffered.

If that is the case then EV6 is seriously flawed. You normally have
non-cached locations buffered (since you don't always need peripheral
device accesses to be posted immediately) and can force a writeback with a
memory barrier. I don't have my 21264 handbook handy, so I can't check
EV6 details at the moment, especially why it is different.

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: macro@ds2.pg.gda.pl, PGP key available        +

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