TXB interrupt of i.MX53 FEC

[torus1000]

Hi,

When I transmitted last buffer in frame, I expected both TXB and TXF would be asserted but sometimes only TXB be asserted.

       TxBD before Tx: Bit31(R)=1, bit27(Last in frame)=1, bit26(Tx CRC)=1, other fields=0
       TxBD after  Tx: Bit31(R)=0, bit27(Last in frame)=1, bit26(Tx CRC)=1, other fields=0

Why is TXF sometimes missing?

Actually it is not a big issue because tx packet always transferred normally according to the Wireshark but it is weird.

In spite of TXF deassert, MIB and following counters increased correctly.

　　　RMON_T_PACKETS, RMON_T_BC_PKT, RMON_T_P64～RMON_T_P1024TO2047,

　　　RMON_T_OCTETS, IEEE_T_FRAME_OK, IEEE_T_OCTETS_OK
I believe TXB is asserted when transmit completed(R=1 to 0). Was TXB also asserted when error occured?

Any help in how to trouble shoot this would be great.
Thanks.

[Yuri]

Please check FEC BD ring and buffers if they are to be properly aligned :

BD ring should 128-bit aligned, receive data buffers – 16-bytes aligned,

transmit buffers - 32-bit aligned.

Have a great day,
Yuri

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[torus1000]

Dear Yuri

Thank you for replying.

Unfortunately I already checked both BD and TX buffer were aligned properly.

Do you have any idea to fix TXF?

Any help would be great.

[Yuri]

Let me look at YOur BDs before and after transfer.

Regards,

Yuri.

[torus1000]

Dear Yuri,

Here is my BD as following. Please have a look.

Bit31:R = 1(Soft set) -> 0(Hard clear)
Bit29:W = 0
Bit27:L = 1
Bit26:TC = 1
Bit25:ABC = 0
Bit24:PTP = 0
Bit15-0:Data Length = <N>

Thanks.