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Description
Specific data send by the 68K to Prometheus over the PCIe bridge to the PCIe Bigfoot card gets dropped.
This is not address specific but data specific and 100% reproducable.
The following error bit is flagged: PEX_CSB_IBSTAT_BRGER = 1
For byte transfers, the following data is lost and the MPC8314E indicates an error on CSB inbound transfer (tested from $00-$C0, i guess I should test till $FF):
$31, $32, $34, $37, $38, $3B, $3D, $3E
Word transfers and longword transfers are harder to predict which ones get dropped, but at least a very vital longword gets dropped which is used in the reset procedure:
$52535445
Old data remains in the memory location the write was supposed to go. It does not lock the card and data can be continued to be send.
Another example; At a location the inital data is 0,0,0,0 in longwords. Writing the following longwords:
$806001E4, $38630001, $906001E4, $4BFFFFF4
Gives the following result:
$806001E4, $00000000, $906001E4, $4BFFFFF4
With further tests just writing $38630001 anywhere in the address range, the results are always that this longword gets dropped with a CSB inbound error.