some instances you may want to override the specified four-stage link equalization procedure to
dynamically tune PMA settings. Follow these steps to override Gen3 equalization:
1. Connect the Transceiver Reconfiguration Controller IP Core to your PHY IP Core for PCI Express as
shown in PCI Express PIPE IP Core Top-Level Modules.
2. For each transmitter port, use the Quartus II Assignment Editor to assign the Transmitter VOD/
Preemphasis Control Source the value RAM_CTL.
3. Recompile your design.
You can now use the Transceiver Reconfiguration Controller to change VOD and pre-emphasis settings.
Related Information
PHY Interface for the PCI Express Architecture PCI Express 3.0
PHY for PCIe (PIPE) Dynamic Reconfiguration
Dynamic reconfiguration calibrates each channel to compensate for variations due to process, voltage,
and temperature (PVT).
For Stratix V devices, each channel and each TX PLL have separate dynamic reconfiguration interfaces.
The MegaWizard Plug-In Manager provides informational messages on the connectivity of these
interfaces. The following example shows the messages for a 8-channel PHY IP Core for PCI Express
(PIPE).
Although you must initially create a separate reconfiguration interface for each channel and TX PLL in
your design, when the Quartus II software compiles your design, it reduces the total number of reconfigu‐
ration interfaces by merging reconfiguration interfaces. The synthesized design typically includes a
reconfiguration interface for at least three channels because the three channels within each transceiver
triplet share a single physical Avalon-MM slave interface which connects to the Transceiver Reconfigura‐
tion Controller IP Core. Conversely, you cannot connect the three channels that share this single physical
Avalon-MM interface to different Transceiver Reconfiguration Controllers. Doing so causes a Fitter error.
For more information, refer to“Transceiver Reconfiguration Controller to PHY IP Connectivity”.
Example 8-1: Informational Messages for the Transceiver Reconfiguration Interface
PHY IP will require 9 reconfiguration interfaces for connection to the
external reconfiguration controller.
Reconfiguration interface offsets 0-7 are connected to the transceiver
channels.
Reconfiguration interface offset 8 is connected to the transmit PLL.
The reconfiguration interface uses the Avalon-MM PHY Management interface clock.
8-24
PHY for PCIe (PIPE) Dynamic Reconfiguration
UG-01080
2015.01.19
Altera Corporation
PHY IP Core for PCI Express (PIPE)
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