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Altera_Forum's avatar
Altera_Forum
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15 years ago

TSE-SGDMA something wrong

Hi all,

I'm working on a custom board with nios2 + tse (10/100/1000) + DDR sdram...

I'm trying to use a driver for triple speed eth under u-boot...the driver has been already tested on an altera demo board and is working fine....

On my custom board...the nightmare....I'm able to transmit correctly a packet (ARP request) to PC but when I get the response (ARP Reply) I find that the first byte of the packet (in the destination mac field) is always dropped...

Really strange...at first I tought to some problem between sgdma_rx and ddr...something like a problem that avoid the first byte to be transferred in memory...

Then I did this...I've enabled the rx_shift16 and I found that the packet is actually shifted by 2 bytes but the first byte of dmac field is always missing...

In other words:

arp request to PC: ff ff ff ff ff ff 01 02 3e 0a etc..

arp reply by PC: 01 02 3e 0a etc..

received : 02 3e 0a etc...

rx_shift16 enabled:

received : 00 00 02 3e 0a

TSE seems always dropping one byte.... I don't know how solve it...

Any help will be appreciated..

Carlo

15 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    I don't think that you need to edit anything in the generated sdc file. However the interface to the PHY chip isn't constrained by that file, and you need to do it yourself.

  • Altera_Forum's avatar
    Altera_Forum
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    Hi,

    I created a SDC file for the PHY DP83848C some time ago. Maybe this file helps you out a little bit.

    Like I understood it is necessary to create the TX and RX Clock in the SDC. After that you have to define which Pins are synchronus to these Clocks.
  • Altera_Forum's avatar
    Altera_Forum
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    Hi all,

    thread is becoming interesting....now it works...

    I upload the constraints changes we added to make it work...obviously changes are due to fully constraint MII interface...

    Carlo :)
  • Altera_Forum's avatar
    Altera_Forum
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    --- Quote Start ---

    I don't think that you need to edit anything in the generated sdc file. However the interface to the PHY chip isn't constrained by that file, and you need to do it yourself.

    --- Quote End ---

    Thanks. I tried to do it but my design still doesn't work. I'm going to be very depressed for this. What made me concerned about timing is a message I got in the "ignored constraints" in TimeQuest. There is a list of "clock creations" commands that comes from tse_constraints.sdc. I'm not an expert in this kind of architecture so my only way to debug by now was trying to run a simple_socket_server application. From NioS side everything seems to work, but I can't reach the erver anyway. DO you have a suggestion to me to break

    the chain and investigate this problem?

    I'm using TSE in RGMII mode.

    Thank a lot.
  • Altera_Forum's avatar
    Altera_Forum
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    The first thing to do in my opinion is to put some signaltap probes on the RGMII interface and see what is going on over there.