UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

cancel
Showing results for 
Search instead for 
Did you mean: 
Participant igal_kroyter
Participant
3,015 Views
Registered: ‎09-13-2016

zynqmp high latency interrupt

Jump to solution

Hello,

 

I have run a small test in which a thread by setting a bit in an AXI register in the PL causing the PL to invoke a PL-to-PS interrupt. An IRQ handler is invoked and resets the register (clearing the interrupt). Two printks are utilized the first one just before the bit is set and another just after the bit is reset (one in the thread context and the second one in the interrupt handler context). The latency between the time tags of the printks is consistently 3.2[mSec].

 

Is there a way to reduce this value by a factor of 10 or so? 

 

Thanks,

 

Igal

0 Kudos
1 Solution

Accepted Solutions
Visitor plastek
Visitor
5,696 Views
Registered: ‎03-27-2014

Re: zynqmp high latency interrupt

Jump to solution

Igal,

do you printk directly to serial console?

If so then this 3.2ms delay may be due to serial port speed.

Consider storing timestamp during first and second operation, calculate difference and then print it out.

The timestamp you can obtain using do_gettimeofday function (it has usec resolution).

 

Regards,

Andrzej.

Tags (1)
0 Kudos
3 Replies
Visitor plastek
Visitor
5,697 Views
Registered: ‎03-27-2014

Re: zynqmp high latency interrupt

Jump to solution

Igal,

do you printk directly to serial console?

If so then this 3.2ms delay may be due to serial port speed.

Consider storing timestamp during first and second operation, calculate difference and then print it out.

The timestamp you can obtain using do_gettimeofday function (it has usec resolution).

 

Regards,

Andrzej.

Tags (1)
0 Kudos
Participant igal_kroyter
Participant
2,983 Views
Registered: ‎09-13-2016

Re: zynqmp high latency interrupt

Jump to solution
Andrzej,
thank you for the reply.

I have tested it again per you suggestion and I received a 3[uSec] latency, which does make sense.

Thanks,

Igal
0 Kudos
Visitor plastek
Visitor
2,946 Views
Registered: ‎03-27-2014

Re: zynqmp high latency interrupt

Jump to solution

Great to hear that :).

 

Regards,

Andrzej.

0 Kudos