Master PCI on Asus A7N266

[Marco Brambilla <marco-tpa.brambilla@st.com>]

Hi everyone,

I have an Asus A7N266 nForce motherboard (bios revision 1001).

I see a strange behaviour on it:

Any kind of master read accesses from any PCI device are never
acknowledged at ftrst trial.
Instead, I always receive 4 disconnect without data and then I am
granted only one data phase, followed by a disconnect.

Mind you, this behaviour is perfectly legal, but by doing so the MB is
crippling the data rate I can obtain:
moving 16 dwords takes more than 10 us rather than less than 1 us as it
should (and it does on motherboards which accept bursts).

Notice that this behaviour is independent on the kind of transaction
used: mem read, mem read line and mem read multiple all get the same
treatment.

Anyone knows why and/or can suggest some tweaking ?
Thanks in advance.

Marco.
-- 
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 Marco BRAMBILLA   
            
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