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PCIe IO BAR's limited to "Legacy Endpoints"

Altera_Forum
Honored Contributor II
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I am looking to define an EP with a BAR defined as IO instead of memory inorder to test the IO / CNFG PCI ordering rules .  

 

I thought it would be as easy as going into an existing design and re-defining the BAR type ... It appears the IO BAR type is only supported by "Legacy Endpoints" . 

 

Does anyone know why this is or how to get around it ? 

 

Thanks, Bob.
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Altera_Forum
Honored Contributor II
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IO style endpoints aren't really supported in PCIe. They only exist so that legacy PCI cards can be attached via a PCIe to PCI bridge. I wouldn't be at all surprised to find out they don't work. I wouldn't be upset about it either. It's basically legacy garbage that should be ignored in a modern design.

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Altera_Forum
Honored Contributor II
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--- Quote Start ---  

IO style endpoints aren't really supported in PCIe. They only exist so that legacy PCI cards can be attached via a PCIe to PCI bridge. I wouldn't be at all surprised to find out they don't work. I wouldn't be upset about it either. It's basically legacy garbage that should be ignored in a modern design. 

--- Quote End ---  

 

Thanks Galfonz. 

 

I'm not particularly interested in IO and understand the point you make but I am interested in testing ordering rules for IO and Configuration Writes / Reads per the specified rules since IO and Configuration are handled differently ... Since IO and Configuration are treated the same with respect to ordering , I thought IO would be easier to implement. 

 

If it is't easy to implement with the hard PCIe IP I have access to ... then I will look to the Keysight and LeCroy Exerciser cards that I have access to.
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Altera_Forum
Honored Contributor II
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It's definitely going to be easier to use something that will generate the kind of traffic you are interested in and a monitor to view what the responses are than it would be to implement something with an FPGA, hard IP or soft.

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