On Thu, 21 Feb 2002, Atsushi Nemoto wrote:
> As I wrote in another mail, TX39's uncached load does NOT return data
> from a write buffer. Uncached load/store always appears on I/O bus in
> same order.
Well, the specification suggests that a load doesn't stall until all data
from the buffer are written back. Therefore a load will appear on the
host bus before pending writes. It implies mb() has to stall on the
"buffer not empty" condition.
> The problem of TX39's write buffer is that cached load/store operation
> can overtake preceding uncached store operation (even if "SYNC" was
> exist between these operations).
It's implied by the above.
--
+ Maciej W. Rozycki, Technical University of Gdansk, Poland +
+--------------------------------------------------------------+
+ e-mail: macro@ds2.pg.gda.pl, PGP key available +
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