looking for a basic PCIe example

Hi,

I'm looking for a high-speed PCI express example, like the one given in this video:

https://www.youtube.com/watch?v=IOHgltR11QY&noredirect=1

but obviously my google-fu is failing me because I can't find an example matching the video.

Does anyone have a DMA example as he shows, or something similar. I've been using Xillybus thus far, which is great but isn't useful for high-speed transfers.

Advance thanks,
Karol.

 

[rupertlssmith@googlemail.]

On Tuesday, March 25, 2014 12:27:04 AM UTC, Karol Hennessy wrote:

Hi,



I'm looking for a high-speed PCI express example, like the one given in this video:



https://www.youtube.com/watch?v=IOHgltR11QY&noredirect=1



but obviously my google-fu is failing me because I can't find an example matching the video.



Does anyone have a DMA example as he shows, or something similar. I've been using Xillybus thus far, which is great but isn't useful for high-speed transfers.



Advance thanks,

Karol.

Hi,

Never heard of Xillybus before, so I was curious to take a look at it.

Why is it not useful for high-speed transfers? Page 17 of this manual discusses high speed IO. I only skim read it, but it seems to discuss the relevant technique, mapping user space RAM as a DMA buffer.

http://xillybus.com/downloads/doc/xillybus_host_programming_guide_linux.pdf

Rupert

 

[Karol Hennessy]

Hi Rupert,

On his website, he says the limits are about 400 MB/s for most devices, which is nothing like the PCIe bandwidth (assuming you've more than one lane).

http://xillybus.com/pcie-download

The limitation seems to be due to the bus width/CPU overhead. The author explains it here:

http://forum.xillybus.com/viewtopic.php?f=2&t=42

To talk to another device, I'll have to write my own driver I think. That's probably too much work for what I want so, I'll probably use some sort of high speed Gb connection.

If you don't need warp-speed, I'd still recommend xillybus. It's extremely easy to use, even for a n00b like me.

Thanks for the response,
Karol.

On Wednesday, 26 March 2014 09:35:10 UTC+1, rupert...@googlemail.com wrote:

On Tuesday, March 25, 2014 12:27:04 AM UTC, Karol Hennessy wrote:

Hi,







I'm looking for a high-speed PCI express example, like the one given in this video:







https://www.youtube.com/watch?v=IOHgltR11QY&noredirect=1







but obviously my google-fu is failing me because I can't find an example matching the video.







Does anyone have a DMA example as he shows, or something similar. I've been using Xillybus thus far, which is great but isn't useful for high-speed transfers.







Advance thanks,



Karol.





Hi,



Never heard of Xillybus before, so I was curious to take a look at it.



Why is it not useful for high-speed transfers? Page 17 of this manual discusses high speed IO. I only skim read it, but it seems to discuss the relevant technique, mapping user space RAM as a DMA buffer.



http://xillybus.com/downloads/doc/xillybus_host_programming_guide_linux.pdf



Rupert