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Arria10 PCIe: no completion for endpoint MRd

Altera_Forum
Honored Contributor II
853 Views

Hello board, 

 

I am using the Arria10 PCIe HIP (avst) as an endpoint. 

 

I have PIO read/write working as well as posted writes. I am trying to get non-posted read working, but I have not had much chance so far. 

 

AFAICT my TLP header looks good, as well as my creds; bus mastering is enabled; but I am not getting neither a completion nor do I see any error reported on the root. 

 

Here is what I am sending (in hex on a 256b bus): 

 

00000000 00000000 00000000 00000000 00000000 00117500 050000FF 00000002 

 

So, in layman terms: 

 

- length = 2 DWORDS 

- first/last byte enable : 0xFF (all) 

- requested ID : 05:00.00 

- host physical address: 0x117500 

 

If anyone has any idea what I am doing wrong, any help would be appreciated. 

 

Thanks !
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2 Replies
Altera_Forum
Honored Contributor II
100 Views

After fiddling with the transaction size I realized that 1 DWORD read request work. Anything bigger than 1 DWORD is ignored. I read somewhere that Avalon-MM interface has a single-dword completer mode; however, I am using the Avalon-ST interface so I don't think it applies.

Altera_Forum
Honored Contributor II
100 Views

So, as it turned out completion were actually sent. It's just that SignalTap would not catch it as it would happen too soon after the previous breakpoint.

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