lkml.org 
[lkml]   [2014]   [Sep]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] spi: qup: Fix incorrect block transfers
On Tue, Sep 23, 2014 at 02:26:13PM -0500, Andy Gross wrote:
> On Tue, Sep 23, 2014 at 12:24:27PM +0300, Ivan T. Ivanov wrote:
> > On Sun, 2014-09-21 at 23:27 -0500, Andy Gross wrote:

> > > This patch fixes a number of errors with the QUP block transfer mode. Errors
> > > manifested themselves as input underruns, output overruns, and timed out
> > > transactions.

> > At what speeds are you seeing those errors?

> We've tried 25MHz and 50MHz. Both fail in the same way. Keep in mind this is
> definitely a timing / race issue and it probably also dependent on the latency
> of the attached device. I cannot reproduce this at all on my IPQ8064 based
> board, but others can.

With SPI everything is entirely clocked from the master - the attached
device can't cause any of those issues unless there's an electrical
problem that *really* upsets the master.
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2014-09-24 10:41    [W:0.037 / U:1.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site