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Date:   Fri, 12 Apr 2019 00:09:30 +0300
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Subject: Re: [PATCH 1/2] stmmac: introduce flag to dynamically disable TX
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At this point I've settled on snps,txpbl = <0x20> by itself.
If I increase the MTU from the default of 1500 I get a stack trace and 
link reset almost immediately:
(https://pastebin.com/raw/5JBtfWei)
whether TX Checksumming is ON or OFF.

That said, with the default MTU, I get better speeds when TX 
Checksumming is on and the PBL tweak is set.

Is there a better option in the horizon for the near future?
At least for the Renegade (the only board I have to test) it can serve 
as a temporary workaround.
Should I make a patch to replace force_thresh_dma_mode with txbpl 
<0x20> for the Renegade specifically?

In any case I would be happy to help as much as I can to figure out if 
it's a board specific thing, or SoC, or even an issue of the Ethernet 
device itself.