MCDMA IP D2H Queue Reset Failure during Channel Re-allocation

Hi Wincent_Altera​ ,

Thanks for your explanation regarding the queue reset timeout. We will increase the timeout value as suggested.

However, we are currently observing a different issue during runtime testing.

Previously, all channels were working correctly in D2H mode when initialized one by one. But now, during testing of same design and same application with/without timeout added:

• When we initialize Channel 1 -> it works fine.
• When we initialize Channel 2 -> it starts reading initially, but after 1-2 seconds, DMA gets stuck.
• If we stop Channel 1 -> Channel 2 immediately resumes normal operation.

Please provide insights regarding the same.

I have a few questions regarding MCDMA behaviour as well:

1. How does channel scheduling or balacing work internally in multi channel mode in AVMM configuration? Is there any mechanism and how to configure it, or do we need to manage balancing from software?
2. Is it possible for one active chanel to starve other channel requests (e.g., due to descriptor fetch or AVMM bandwidth sharing)?
3. We also observe that during each channel initialization, the queue reset sequence for each new channel initialized takes even more time.

Please provide concrete reasoning.

Regards,
Ashoo