On Fri, 15 Feb 2002, Atsushi Nemoto wrote:
> Note that SYNC on TX39/H and TX39/H2 does not flush a write buffer.
That's perfectly fine -- it does not need to. It's only a
synchronization point.
> Some operation (for example, bc0f loop) are required to flush a write
> buffer.
This is bad, though. No extra operations must be needed. After a "sync"
the buffer should be written back as soon as not doing so would be visible
externally. IOW, two consecutive writes separated by a "sync" need not
imply a write-back, but as soon as a read happens a preceding write-back
is a must.
It sounds weird: it looks like "sync" is useless and basically a "nop".
If this is the case the processors need their own wbflush()
implementation. Can you point to specific chapters of specifications that
document it?
--
+ Maciej W. Rozycki, Technical University of Gdansk, Poland +
+--------------------------------------------------------------+
+ e-mail: macro@ds2.pg.gda.pl, PGP key available +
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