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Replace MAC block with SGMII

Altera_Forum
Honored Contributor II
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Hi All, 

 

I have a MII interface with 10/100 support in which MAC block is used 

as IP in my design. 

I am doing feasibility study of removinf MAC block to external L2 

component and use SGMII to support 10/100/1000. 

Is this possible? Also please let me know how are SerDes Channels 

listed in FPGA datasheets related to SGMII. 

 

Thanks, 

Sundar
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6 Replies
Altera_Forum
Honored Contributor II
436 Views

I am a bit confused by your post. 

 

Are you saying that you currently have a 10/100 MAC with an external MII interface in your FPGA and that you want to replace it with a 10/100/1000 MAC with an external SGMII interface? 

 

You will always need a MAC function whether you use MII or SGMII. For Gigabit Ethernet the standard interface is GMII but this is converted to SGMII etc by an additional function called PCS. This sits between the MAC and external PHY. 

 

Have you had a look at the Altera Triple Speed Ethernet MAC (TSE)? It might be what you are after 

 

Hope this helps
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Altera_Forum
Honored Contributor II
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Hi, 

Thanks for your reply. 

 

I do have a MAC Ip in my FPGA. This is interfacing with external PHY and internally for GFP processing. This MAC supports 10/100 currently using MII at PHY i/f. 

 

My idea is to remove this MAC block from FPGA. Put this MAC block in L2 switch. Improve support up to 10/100/1000. This block has to interface with FPGA - GFP block. Towards this interface do I need SGMII or SerDes? 

 

I am also looking in to Altera Tri Speed Mac but unable match my requirements as described above.
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Altera_Forum
Honored Contributor II
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Your L2 Switch will probably have an SGMII Interface so will still need an SGMII interface and MAC on your FPGA.  

 

To all intensive purposes the L2 switch would look like a PHY to the FPGA MAC. 

 

I believe the TSE is the way to go, put an SGMII interface out of your FPGA and connect to the L2 switch SGMII (Which will need to be configured in PHY mode NOT MAC Mode as SGMII is not symmetrical). 

 

This would give you n ports of 10/100/1000 depending on what your switch provides
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Altera_Forum
Honored Contributor II
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Thanks for the reply. 

 

Based on your reply I understand I will still need MAC to be in my FPGA interfacing with external L2 using SGMII. 

 

I am exploring Megawizard Plug-in Manager to create this IP.To apply your solution I believe I have to choose 10/100/1000Mb Ethernet MAC with 1000Base-x/SGMII PCS.  

With your experience Could you please suggest some optimal configuration in terms of MAC options/FIFO options/SGMII options in the wizard. I will definitely need to configure this wizard as per my requirements but I will use your suggestions as key inputs. 

 

Also one additional query- do i need to choose GX family with SerDes options used for thsi interface?
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Altera_Forum
Honored Contributor II
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Thats what I would suggest. 

 

You don't really have to use SGMII, you could use GMII or RGMII is you have enough spare pins on your FPGA and if your L2Switch supports it (What part are you considering?). I believe you'll need a GX if you want to use SGMII but am not 100% sure. Others on the forum will be able to help or you could look at the TSE documents. 

 

I cannot really suggest which options to use as it all depends on your final application and to be fair it is a little while since I have used it! 

 

Hope this has been of some help and good luck with you project
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aarki1
Beginner
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I believe the TSE is the way to go, put an SGMII interface out of your FPGA and connect to the L2 switch SGMII (Which will need to be configured in PHY mode NOT MAC Mode as SGMII is not symmetrical). 

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