>>>>> On Fri, 15 Feb 2002 13:08:20 +0100 (MET), "Maciej W. Rozycki"
>>>>> <macro@ds2.pg.gda.pl> said:
macro> IOW, two consecutive writes separated by a "sync" need not
macro> imply a write-back, but as soon as a read happens a preceding
macro> write-back is a must.
TX39 satisfy this on uncached load/store. "sync" does not flush a
write buffer, but any uncached load are executed AFTER completion of
pending uncached store. On combination of cached and uncached
operation, TX39 does not satisfy this order.
macro> It sounds weird: it looks like "sync" is useless and basically
macro> a "nop".
TX39 has a function called "non-blocking load". This function is
described on chapter 4.4 of TX39/H2 manual. "sync" operation is
meaningful with this function.
macro> If this is the case the processors need their own wbflush()
macro> implementation. Can you point to specific chapters of
macro> specifications that document it?
Chapter 4.9.4 in TX39/H2 Japanese manual describes write buffer. But
I could not find it in the English manual...
---
Atsushi Nemoto
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