
PI7C8150B
2-PORT PCI-TO-PCI BRIDGE
ADVANCE INFORMATION
Page 39 of 115
July 31, 2003 – Revision 1.031
Table 3-8. Response to Posted Write Target Termination
Target Termination
Normal
Target Retry
Target Disconnect
Target Abort
Repsonse
No additional action.
Repeating write transaction to target.
Initiate write transaction for delivering remaining posted write data.
Set received-target-abort bit in the target interface status register. Assert
P_SERR# if enabled, and set the signaled-system-error bit in primary status
register.
Note that when a target retry or target disconnect is returned and posted write data
associated with that transaction remains in the write buffers, PI7C8150B initiates another
write transaction to attempt to deliver the rest of the write data. If there is a target retry, the
exact same address will be driven as for the initial write trans-action attempt. If a target
disconnect is received, the address that is driven on a subsequent write transaction attempt
will be updated to reflect the address of the current DWORD. If the initial write transaction
is Memory-Write-and-Invalidate transaction, and a partial delivery of write data to the
target is performed before a target disconnect is received, PI7C8150B will use the memory
write command to deliver the rest of the write data. It is because an incomplete cache line
will be transferred in the subsequent write transaction attempt.
After the PI7C8150B makes 2
24
(default) write transaction attempts and fails to deliver all
posted write data associated with that transaction, PI7C8150B asserts P_SERR_L if the
primary SERR_L enable bit is set (bit 8 of command register for secondary bus) and
posted-write-non-delivery bit is not set. The posted-write-non-delivery bit is the bit 2 of
P_SERR_L event disable register (offset 64h). PI7C8150B will report system error. See
Section 6.4 for a discussion of system error conditions.
3.8.3.3
DELAYED READ TARGET TERMINATION RESPONSE
When PI7C8150B initiates a delayed read transaction, the abnormal target responses can be passed
back to the initiator. Other target responses depend on how much data the initiator requests.