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 +
