cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
skos
Visitor
Visitor
327 Views
Registered: ‎09-28-2020

VPSS bypass vdma

Jump to solution

We are planning a system that incorporates a a VPSS core, in full-fledged mode since we need some of the features only available in full-fledged mode. Our problem is that in our system when we want the output video to be the same size as the input,  the VDMA will consume too much memory bandwidth even though it is not really necessary.


Can the VDMA be somehow bypassed or disabled for this case?

0 Kudos
1 Solution

Accepted Solutions
florentw
Moderator
Moderator
238 Views
Registered: ‎11-09-2015

Hi @skos 

Looking a the VPSS driver, it seems that the AXI VDMA will always be enabled even if scaling ratio is 1:

https://github.com/Xilinx/embeddedsw/blob/f975a0ea90930587ab55e4d920a31950bd373fa8/XilinxProcessorIPLib/drivers/vprocss/src/xvprocss_router.c#L223

You could try to edit the driver to change the internal routing of the VPSS to avoid going to the AXI VDMA. However, this is not supported by Xilinx (thus not recommended). So you would need to do you own characterization to make sure it can work or not


Florent
Product Application Engineer - Xilinx Technical Support EMEA
**~ Don't forget to reply, give kudos, and accept as solution.~**

View solution in original post

0 Kudos
1 Reply
florentw
Moderator
Moderator
239 Views
Registered: ‎11-09-2015

Hi @skos 

Looking a the VPSS driver, it seems that the AXI VDMA will always be enabled even if scaling ratio is 1:

https://github.com/Xilinx/embeddedsw/blob/f975a0ea90930587ab55e4d920a31950bd373fa8/XilinxProcessorIPLib/drivers/vprocss/src/xvprocss_router.c#L223

You could try to edit the driver to change the internal routing of the VPSS to avoid going to the AXI VDMA. However, this is not supported by Xilinx (thus not recommended). So you would need to do you own characterization to make sure it can work or not


Florent
Product Application Engineer - Xilinx Technical Support EMEA
**~ Don't forget to reply, give kudos, and accept as solution.~**

View solution in original post

0 Kudos