RE: streaming PCI / STOP after 4/8 words

[André David <Andre.David@cern.ch>]

> When I do as master read transfers to the memory with pci
> 32-66Mhz on a tyan
> thunder HEsl S2567 under NT4.0
> I get a STOP signal  after 8 words with the read multiple
> command, and after
> 4 words with the memory read command.

I bet it's a chipset PCI-to-host bridge problem. Perhaps the buffer for Main
memory to PCI reading is only 8 words long.

I have been seeing something similiar when, with the CPU I read PCI memory.
The largest read is of 2x32bit words (using MMX instructions and registers).
Even with SSE 128bit registers/instructions, you get two "64bit"
transactions.

> How can I avoid that the motherboard send a stop after 4 or 8
> words so that
> my burst lenght is greather ?

Well, in my case I have now been told no thing can be done. In yours it's
strange since the reading from PCI masters should be optimized.

Hope it helps,

André