Is it a supported device? https://dd-wrt.com/wiki/index.php/Supported_Devices#TP-Link
From what I can remember it looks like one that is. I'll be able to check when I get home.
The R6400 is supported. Apparently 'Kong' (a DD-WRT firmware developer) uses one.
@boristrump started
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Is it a supported device?
https://dd-wrt.com/wiki/index.php/Supported_Devices#TP-Link