Access Control Services; Table 9.3 Downstream To Upstream Port Interrupt Routing Based On Device Number - Renesas IDT 89HPES48H12G2 User Manual

IDT Theory of Operation
Notes
PES48H12G2 User Manual
INTA
Device (N mod 4) =
0 INTA
Device (N mod 4) =
Downstream
1 INTD
1
Device
Device (N mod 4) =
Interrupt
2 INTC
Device (N mod 4) =
3 INTB

Table 9.3 Downstream to Upstream Port Interrupt Routing Based on Device Number

1.
Device X INTy corresponds to external downstream generated INTy interrupts and INTy interrupts generated by the
port.
If a Downstream Port goes down (i.e., transition to DL_Down state) or is removed from a partition, the
INTx virtual wires associated with that port are negated, and the upstream port's aggregate state is updated
accordingly. This may result in the upstream port generating a Deassert_Intx message.

Access Control Services

The PES48H12G2 ports support Access Control Services (ACS) as defined in the PCI Express 2.0
Specification. In the PES48H12G2, ACS functionality is only performed by ports operating in Downstream
Switch Port mode. A port operating in Downstream Switch Port mode supports the following ACS opera-
tions:
– ACS Source Validation
– ACS Translation Blocking
1
– ACS Peer-to-Peer Request Redirect
– ACS Completion Redirect
– ACS Upstream Forwarding
– ACS Peer-to-Peer Egress Control
– ACS Direct Translated Peer-to-Peer
ACS is programmed via the ACS Capability Structure in a function's configuration space. ACS checks
are only applied to TLPs flowing in the upstream direction.
– For a downstream port, these are TLPs that are received from the port's link, regardless of the
final destination of the TLP (e.g., regardless of whether the TLP is going to the upstream port or
a peer downstream port).
When a ACS causes a TLP to be re-directed, the re-direction is implemented such that TLPs received
by a port that are ACS re-directed follow the ordering rules (for more information, contact
ssdhelp@idt.com). Specifically, non-relaxed-ordered completion TLPs that are re-directed towards the root-
complex can't pass previously received posted TLPs re-directed in the same direction.
The following figures show examples of ACS checks applied to TLPs. Figure 9.1 shows an example of
ACS source validation at a downstream port. In this case, the offending TLP is dropped and a completion
with completer-abort status is generated.
1.
For a port operating in Downstream Switch Port mode, 'peer-to-peer' implies traffic received by the downstream
port via the PCIe link that is destined towards another downstream port in the same partition.
Upstream Port Interrupt (Port 0)
INTB
Device (N mod 4) =
0 INTB
Device (N mod 4) =
1 INTA
Device (N mod 4) =
2 INTD
Device (N mod 4) =
3 INTC
9 - 3
INTC INTD
Device (N mod 4) = Device (N mod 4) =
0 INTC 0 INTD
Device (N mod 4) = Device (N mod 4) =
1 INTB 1 INTC
Device (N mod 4) = Device (N mod 4) =
2 INTA 2 INTB
Device (N mod 4) = Device (N mod 4) =
3 INTC 3 INTA
April 5, 2013