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Altera_Forum's avatar
Altera_Forum
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13 years ago

PCIe as Soft-IP via CMU as transceiver in Stratix-IV

Hi,

in a design using a Stratix-IV EP4SGX230KF40, all regular transceiver channels are already used for other connections, but I want to connect a PC-module via a PCIe 1.1 x1 link.

Is this in any way possible? The CMU-channels are said to be usable for transceiver operation as well, but apparently they lack functionality to be connected to the PCIe Soft-IP

core.

Any advice?

Thx

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    Soft PCI-e still requires transceivers, so I doubt You'll be able to implement it without freeing at least two pairs for TX/RX.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    You're probably out of luck here. The problem with the CMU channels is that they don't have the PCS layer. Most soft IP vendors for FPGAs that have PCIe cores require a PIPE interface to the transceiver. I don't know if anything has changed in the last year, but last I checked, no one had the PIPE PCS done in soft logic. I also don't know if the CMU channels have the logic to do link detection that's required by PCIe (they might). You're better off moving one of the other channels to the CMU and using a full channel for the PCIe.