Date: Tue, 11 Jun 2024 09:36:08 +0200
From: Jiri Slaby <jirislaby@...nel.org>
To: Ferry Toth <fntoth@...il.com>, neil.armstrong@...aro.org,
 gregkh@...uxfoundation.org
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Subject: Re: [PATCH 00/15] tty: serial: switch from circ_buf to kfifo

On 10. 06. 24, 22:16, Ferry Toth wrote:
>> One question though: in 8250_dma.c serial8250_tx_dma() you mention "/* 
>> kfifo can do more than one sg, we don't (quite yet) */".
>>
>> I see the opportunity to use 2 sg entries to get all the data out in 
>> one dma transfer, but there doesn't seem to be much documentation or 
>> examples on how to do that. It seems just increasing nents to 2 would 
>> do the trick?
> 
> Nevertheless I got this to work. Very nice. Thanks for this series.
> I am seeing only 2 interrupts (x2 as each interrupt happens twice), one 
> for dma complete. The 2nd, not sure but likely, uart tx done.
> In any case the whole buffer is transferred without interchar gaps.
> 
>> So, what was the reason to "don't (quite yet)"?
> 
> Before considering to send out a patch for this, are there any caveats 
> that I'm overlooking?

Not any I am aware of. It just needed testers.

Please send a patch.

thanks,
-- 
js
suse labs

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