Re: [PATCH v2 0/6] atmel_serial: Cleanups, irq handler splitup & DMA

but I noticed that I sometimes get an input overrun (ttyS0: 1
input overrun(s) ) during stress conditions.
This is something I did not notice before, maybe it was already there,
or has something changed in this area that it is now more sensitive
for this?
Hmm...is this with or without DMA?

DBGU is without DMA.

If it's without DMA, something very strange is going on -- the non-DMA
RX code is almost the only thing left in the hardirq handler, so I
would really expect overruns to be much less likely to occur now than
before...

As mentioned, maybe it was already there, but I did not run into it
earlier. I have to figure that out. But, at 115200 and a 1 byte
receive-'fifo' on DBGU, and still interrupt locks somewhere in the
tree up to 300us, it is a simple calculation that we can run into
overrun conditions...
Notice that without these interrupt handler splitup, it was much, much
much worse...

So, for me it is not a big deal, because it is just a terminal, and
with my shaky fingers I usually do not type that fast ;-))

Remy

Kind Regards,

Remy
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