F-Tile Architecture and PMA and FEC Direct PHY IP User Guide

ID 683872
Date 7/08/2024
Public
Document Table of Contents

2.1.3. PMA Data Rates

The PMA data rate is dictated by the datapath clocking mode and PMA type you select.

For speed grade information, see the Agilex™ 7 Device Data Sheet .

Table 6.  PMA Data Rate Ranges by Datapath Clocking Mode
Datapath Clocking Mode Configuration Data Rate Range
FHT PMA FGT PMA

PMA clocking mode

(maximum 906.25 MHz)

PMA Direct
  • 24-29 Gbps NRZ
  • 48-58 Gbps NRZ and PAM4
  • 96-116 Gbps PAM4
  • 1-29 Gbps NRZ 1
  • 20-58 Gbps PAM4 2

System PLL clocking mode

(maximum 1 GHz)

PMA Direct

Other configurations with MAC, PCS, and FEC

  • 1-32 Gbps NRZ1
  • 20-58.125 PAM42
Table 7.  Fracture Type Used by Mode
Fracture Type Ethernet Mode PMA Direct Mode3 0 FEC Direct Mode
FGT FHT FGT FHT FGT FHT
st_x1 10GbE-1, 25GbE-1 25GbE-1 One lane with PMA width ≤ 32 One lane with PMA width ≤ 32 One lane with PMA width ≤ 32 One lane with PMA width ≤ 32
st_x2 50GbE-1, 50GbE-2 50GbE-1, 50GbE-2 One lane with PMA width = 64 One lane with PMA width = 64

Two bonded lanes with PMA width ≤ 32

One lane with PMA width = 64

Two bonded lanes with PMA width ≤ 32

One lane with PMA width = 64

st_x4 40GbE-4, 100GbE-2, 100GbE-4 100GbE-1, 100GbE-2, 100GbE-4 Not used One lane with PMA width = 128

Four bonded lanes with PMA width ≤ 32

Two bonded lanes with PMA width = 64

Four bonded lanes with PMA width ≤ 32

Two bonded lanes with PMA width = 64

One lane with PMA width = 128

st_x8 200GbE-4, 200GbE-8 200GbE-2, 200GbE-4 Not used Not used

Eight bonded lanes with PMA width ≤ 32

Four bonded lanes with PMA width = 64

Four bonded lanes with PMA width = 64

Two bonded lanes with PMA width = 128

st_x16 200GbE-4, 400GbE-8 200GbE-4, 400GbE-4 Not used Not used Eight bonded lanes with PMA width = 64 Four bonded lanes with PMA width = 128

PMA Direct modes, unlike Ethernet and FEC Direct modes, do not use the underlying logic of the fracture (MAC, PCS, or FEC). The following examples illustrate the differences between Ethernet and FEC Direct modes and PMA Direct modes.

  • PMA width = 32 example:
    • 100GbE-4 Ethernet link using four PMAs – four bonded lanes of 25.78125 Gbps
      • One st_x4 fracture is used.
    • 100 Gbps PMA Direct link using four PMAs – four bonded lanes of 25.78125 Gbps
      • Four st_x1 fractures are used.
    • 100 Gbps FEC Direct link using four PMAs – four bonded lanes of 25.78125 Gbps
      • One st_x4 fracture is used.
  • PMA width = 64 example
    • 400GbE-8 Ethernet link using eight PMAs – eight bonded lanes of 53.125 Gbps
      • One st_x16 fracture is used.
    • 400 Gbps PMA Direct link using eight PMAs – eight bonded lanes of 53.125 Gbps
      • Eight st_x2 fractures are used.
    • 400 Gbps FEC Direct link using eight PMAs – eight bonded lanes of 53.125 Gbps
      • One st_x16 fracture is used.
1 You must use the system PLL clocking mode for data rates between 29 Gbps and 32 Gbps NRZ.
2 FGT Quad0 can only support 20-32 Gbps PAM4. FGT Quad1, Quad2, and Quad3 can support 20-58 Gbps PAM4.
3 When using a bonded configuration in PMA Direct mode, the number of bonded PMA lanes determines the number of fractures used. For example:
  • Two, four, eight, and 16 bonded FGT lanes with a PMA width ≤ 32 use two, four, eight, and 16 st_x1 fractures, respectively.
  • Two, four, and eight bonded FGT lanes with a PMA width = 64 use two, four, and eight st_x2 fractures, respectively.
  • Two and four bonded FHT lanes with a PMA width ≤ 32 use two and four st_x1 fractures, respectively.
  • Two and four bonded FHT lanes with a PMA width = 64 use two and four st_x2 fractures, respectively.
  • Two and four bonded FHT lanes with a PMA width = 128 use two and four st_x4 fractures, respectively.