CertusPro-NX SerDes/PCS Usage Guide
Preliminary
Technical Note
20
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FPGA-TN-02245-0.81
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PCI Express Link Layer (x1 + x4)
MPCS x4
PCI Express PCS
PMA (SERDES)
Channel 0
Rx
C
D
R
Tx
P
LL
PMA (SERDES)
Chan nel 1
Rx
C
D
R
Tx
P
LL
PMA (SERDES)
Chan nel 2
Rx
C
D
R
Tx
P
LL
PMA (SERDES)
Channel 3
Rx
C
D
R
Tx
P
LL
LMMI
TLP
UCFG
LMMI
MPCS
EPCS
FPGA Core
PMA Controller
Figure 5.2. CertusPro-NX SerDes/PCS Quad Architecture
shows the specific block usage for the corresponding SerDes/PCS mode.
Table 5.3. Block Usage for the Corresponding SerDes/PCS Mode
SerDes/PCS Mode
PCI Express
MPCS
PMA Only
PIPE
PMA
√
√
√
√
PMA Controller
√
√
√
√
PCI Express PCS
√
—
—
√
PCI Express Link Layer Quad
√
—
—
—
MPCS
—
√
—
—
PCI Express Architecture
The CertusPro-NX PCI Express Link Layer block is a hard IP, which supports PCI Express Gen1, Gen2, and Gen3, and is
compatible with PCI-SIG PCI Express Base Spec version 3.1a. The PCI Express Link Layer Block implements PHY Layer
adaption, Data Link Layer, and Transaction Layer. The PCI Express Link Layer block together with PCI Express PCS, PMA
Controller and PMA, constitute the complete PCI Express Hard IP block.
The PCI Express Hard IP supports both Endpoint and Root Complex modes. It supports up to four physical functions.
Each of the four functions has independent PCI Express configurations space. It also supports ECC and parity data path
protection. You can configure this IP as PIPE mode, which is compliant to industry PIPE standard version 4.4, by
bypassing Link Layer block. The LMMI interface is provided in the top wrapper that is to be used in user-controlled IP
core configuration.
The PCI Express Link Layer Quad for all CertusPro-NX devices has four PIPE interfaces that can be used in different
number of links. This can provide the maximum flexibility, depending on the bandwidth of the application
requirements.
shows the architecture of the CertusPro-NX PCI Express Hard IP. There are four physical functions in the Link
Layer ×4 block. There are four physical functions in the Link Layer ×1 block. Total there are eight physical functions in
one Link Layer Quad. PCI Express Configuration Space access and Error Reporting are done through the dedicated
interface (PCI Express Configuration Register Interface, UCFG). The core Configuration and Status Registers can be
accessed using the corresponding LMMI interface per Link Layer block. PCI Express Link Layer block interface to PCI