• State TI Thinks Resolved
  • Locked Locked
  • Replies 10 replies
  • Answers 3 answers
  • Subscribers 98 subscribers
  • Views 2300 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AM57x GMAC_SW questions

Michi Yama
Guru 10030 points

Other Parts Discussed in Thread: AM5728

Hi,

I have some question regarding GMAC_SW.

As you know, GMAC_SW has three ports. Port0 is for Host port. Port1 is for GMIII0/RGMII0/RMII0. Port2 is for GMII1/RGMII1/RMII1.

And then, the MAC address for Port1 is stored at CTRL_CORE_MAC_ID_SW0-1. The MAC address for Port2 is stored at CTRL_CORE_MACID_SW_2-3.

My question is the below.

Q1) Is the above my understanding correct?

Q2) If user would like to use unique MAC address, how to handle it?  Because CTRL_CORE_MAC_ID_SW_0-3 is read only. It can't be overwritten. My customer uses only Port1(PHY is only connected to Port1).

Q3) My customer make the unicast address table entry on ALE.

       PORT_NUMBER (Bit67:66) =0
       BLOCK=0 (Bit 65) = 0
       SECURE (Bit 64) = 0
       UNICAST_TYPE (Bit63:62) = 0 (not ageable)
       ENTRY_TYPE (Bit61:60) = 1 (Address entry)
       Bit47:0 = customer's MAC address (customer's unique address)

In this case, can ARP command be used?

Please let me know.

I appreciate your quick reply.

Best regards,

Michi

  • 0
    TI__Guru**** 393215 points
    Hi,

    1. Yes.
    2. If they want to use different MAC addresses than the factory-programmed ones, they will need to program them in an external memory. The EEPROM used in all Sitara EVMs has allocated space for this. Then they will need to modify the software they use so that it reads the MAC address from the EEPROM instead of internal registers.
    3. I can't help on this. I have asked the Ethernet experts to comment.
  • 0 in reply to Biser Gatchev-XID
    Guru 10030 points

    Dear Biser-san,

    Thank you for your quick reply. It is very helpful for me.

    Regarding q3, I will wait reply from  your Ethernet expert.

    Regarding q2,  I would like to confirm more information. I understand customer must be prepare unique ID in external memory. But I don't know how AM5728 distinguish unique MAC address. AM5728 knows factory programmed MAC address is for Port1 or Port2. But AM5728 does not know which unique MAC address is for Port1 or Port2. How does customer handle this issue?

    Please advise me again.

    Best regards,

    Michi

  • 0
    TI__Guru**** 393215 points

    Michi Yama said:
    And then, the MAC address for Port1 is stored at CTRL_CORE_MAC_ID_SW0/1. The MAC address for Port2 is stored at CTRL_CORE_MACID_SW_2/3.

    Software reads the MAC addresses from the read-only registers above and copies them in the GMAC_SW PORT registers P1_SA_LO/HI resp. P2_SA_LO/HI.

  • 0 in reply to Biser Gatchev-XID
    TI__Mastermind 41230 points

    Concerning Q3, if I understand the question you should be able to use ARP process, this will set the ALE as needed without having to setup an entry from the application. Is Linux the OS?

  • 0 in reply to Schuyler Patton
    Guru 10030 points
    Dear Schuyler-san,

    Thank you for your reply.

    > if I understand the question you should be able to use ARP process, this will set the ALE as needed
    > without having to setup an entry from the application.
    I would like to confirm you said as the above. Your meaning is that my customer's unicast entry on
    ALE is correct, and ARP should use with this entry?

    > Is Linux the OS?
    No. My customer uses Windows Embedded Compact 7, not Linux.

    I appreciate your quick reply.

    Best regards,
    Michi
  • 0 in reply to Michi Yama
    TI__Mastermind 41230 points

    Hi Michi,

    You may need to contact the Vendor who provided the OS. Though, is this the person asking the question?

    In Linux the CPSW driver configures the ALE so the basic steps of network connectivity such as ARP and DHCP processes work. The user level application does not have to do basic setup of the ALE, this should be done by the CPSW driver of the OS being used.

    Best Regards,

    Schuyler

  • 0 in reply to Schuyler Patton
    Guru 10030 points
    Dear Schuyler -san,

    Thank you for your support.

    I have more question regarding ALE. So I will make new thread for my question.
    If you are possible, please support to other thread.

    Best regards,
    Michi
  • 0
    Guru 10030 points

    Hi,

    I have some questions reagrding AM5728 GMAC_SW ALE.

    I would like to know the hardware logic behavior of GMAC_SW of Am5728.

    According to TRM,

    Port 0 is refferred  to the Host Port.

    Port 1 is referred to the interfaces GMII0/RGMII0/RMII0.

    If ARP is received by Port1, GMAC_SW send the ARP to Port0 based on the entry on ALE. The transfer from Port 1 to Port 0 is executed by hardware.

    Question)

    1) Is the above my understanding right?

    2) If the answer of question1 is yes, what is the entry for sending ARP frame to Port1 from Port0?

        Now customer makes the unicast entry on ALE as below.

               PORT_NUMBER (Bit67:66) =0
               BLOCK=0 (Bit 65) = 0
               SECURE (Bit 64) = 0
               UNICAST_TYPE (Bit63:62) = 0 (not ageable)
               ENTRY_TYPE (Bit61:60) = 1 (Address entry)
               Bit47:0 = customer's MAC address( customer's unique address)

       Can ARP is sent to port 0 by only this enry?

    3)  Regarding send the data : my question 1 and 2 is for receive action. I would like to know how to send from Port 0(CPPI) to Port1. What configuration is needed for its action?

    Please advise me.

    I appreciate your quick reply.

    Best regards,

    Michi

  • 0 in reply to Michi Yama
    TI__Mastermind 41230 points

    The answers to question 1 is that your understanding is correct. The entry described also looks correct. Are you not seeing the packets coming in?

  • 0 in reply to Schuyler Patton
    Guru 10030 points

    Dear Schuyler-san,

    Thank you for your support.

    > Are you not seeing the packets coming in?

    YES. Customer's Ethernet of AM5728 is not stable. So customer would like to confirm the spec of GMAC_SW.

    Customer's system with AM5728 has IP address (1.1.0.11). And customer's main system, it is connected to AM5728 system through the ethernet, this system sends a packet by using UDP when system power on. In this timing, main system sends  ARP for searching MAC address (1.1.0.11: AM5728 system ) to the network. Customer does not know that their entry is correct for ARP, or not. So they asked this question.

    Also they would like to get answer of Q3.  Please give me your answer.

    I appreciate your quick reply.

     

    Best regards,

    Michi