RE: MPC85xx PCI transfer disconnect

I know this is probably a question for Freescale directly, 
but I thought I would post here to see if anyone else has 
seen similar issues with the MPC85xx PCI under Linux.

I'm using a Freescale MPC85xx (8541) processor and seeing an 
extreme slowness to the PCI bus.

I'm attemping to do 2048 byte PCI burst reads from an 
external PCI master.  So an external chip is the PCI master 
("initiator") and the MPC85xx is the PCI slave ("target")

When initiating the PCI burst read, there is a 270 ns delay 
from the MPC85xx claiming the transaction (DEVSEL# going low) 
to being ready (TRDY# going low).  Then 64 bytes (a single 
cacheline) are transferred, and TRDY# goes inactive.  Next, 
STOP# goes low, terminating the transfer.  I believe this is 
considered a PCI DISCONNECT type 1 since IRDY# is active the 
entire time.

The 85xx cacheline is 32 bytes. 
Did you enable Memory Read Multiple command of your PCI master?

What I would expect is that the entire 2048 bytes are 
transferred in one PCI bus mastership, but instead there are 
several re-arbitrations and long delays in between several 64 
byte transfers.

Additional info:
The PCI bus is 64bit running at 66 MHz.
I'm running a modified Linux 2.6.9 kernel (elinos-111).
The PCI CCSR piwar1 = 0xa0f4401d.

Freescale has an FAQ 21021 that describes having a PCI 
DISCONNECT 2, which sounds similar to my problem, but I've 
already confirmed I'm doing what the FAQ suggests (enable 
prefetching in the piwar register)
(http://www.freescale.com/webapp/sps/utils/SingleFaq.jsp?FAQ-2

1021.xml)

Any thoughts/suggestions would be appreciated,
Tim
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