DS540 Datasheet, PDF (32/45 Pages) Xilinx, Inc – Supports PCIe access to PLB space

LogiCORE IP PLBv46 RC/EP Bridge for PCI Express (v4.07.a)
Messages
All messages are terminated in the Bridge. When a Vendor Message is received, the response depends on the type.
If a Type 1 Vendor message is received, the packet is discarded. If a Type 0 Vendor message is received, the message
is discarded and the MUR interrupt is issued to the Bridge Interrupt Status register.
PCIe Max Payload Size, Max Read Request Size or 4K Page Violated
It is the responsibility of the requester to ensure that the outbound request adhere to the Max Payload Size, Max
Read Request Size, and 4k Page Violation rules. If the master bridge receives a request that violates one of these
rules, the bridge processes the invalid request as a valid request, which can result in the return of a completion that
violates one of these conditions or the loss of data. The master bridge does not return a malformed TLP completion
to signal this violation.
Completion Packets
A situation can exist where the PCIe read request may ask for more data than the Bridge can insert into a single
completion packet. This situation can exist when the MAX_READ_REQUEST_SIZE is greater than the
MAX_PAYLOAD_SIZE. When this situation occurs, multiple completion packets are generated up to the
MAX_PAYLOAD_SIZE, except for the last one, which is the remainder of the request.
Poison Bit
When the poison bit is set in a transaction layer packet (TLP) header, the payload following the header is corrupt.
When the Bridge receives a memory request TLP with the poison bit set, it discards the TLP and issue the Master
Error Poison (MEP) interrupt to the Bridge Interrupt Status register. When the Bridge receives a configuration
request with the poison bit set, it returns a completion with Status = Unsupported Request.
Zero Length Requests
When the Bridge receives a read request from a remote requester with the Length = 0x1, FirstBE = 0x00, and LastBE
= 0x00, it responds by sending a completion with Status = Successful Completion. When the Bridge receives a (non-
posted) write request from a remote requester with the Length = 0x1, FirstBE = 0x00, and LastBE = 0x00, it has no
effect.
TLP Byte Enables
The Bridge does not support non-contiguous byte enables in PCIe to PLB write request TLPs. When they are
detected, the write request is discarded and the NBE interrupt is set in the Bridge Interrupt Status register. The
Bridge is capable of supporting a read request from the Root Complex that has the allowed non-contiguous TLP
byte enables.
DS540 June 22, 2011
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Product Specification