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From: "Sean Nyekjær" <sean.nyekjaer-rjjw5hvvQKZaa/9Udqfwiw@public.gmane.org>
To: <linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Cc: <kibo-rjjw5hvvQKZaa/9Udqfwiw@public.gmane.org>
Subject: imx spi performance
Date: Wed, 9 Mar 2016 09:26:31 +0100	[thread overview]
Message-ID: <56DFDE37.9060606@prevas.dk> (raw)

Hi

We are getting a very low throughput with the imx6q and the spi 
interface :-(
I have tried both with gpio CS and HW CS.

With gpio CS:
I have a imx6q hooked up to 4x spi uarts(sc16is750) running 4MHz,
using 2 spi channels and 4 chipselects.
With HW flowcontrol @ 115200 8n1, and full duplex on all 4 uarts,
we are getting a maximum throughput of 69841 bits/sec.
That to me seems very slow.

With HW CS:
It does not seem to work as CS is shifted for every
BITS_PER_WORD and that is not compliant with most spi devices.

Does someone have any ideas we can try to boost the performance.

/Sean

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                 reply	other threads:[~2016-03-09  8:26 UTC|newest]

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