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From: Chris Packham <judge.packham@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 0/1] i2c: mvtwsi: running from flash ROM
Date: Thu, 12 May 2016 14:55:58 +1200	[thread overview]
Message-ID: <1463021759-9966-1-git-send-email-judge.packham@gmail.com> (raw)

We have a board using Marvell's MV78100 SoC (note despite the name this
is quite different to the armada MV782x0/MV784x0 SoCs).

The SoC support isn't upstream but since it's quite similar to the
Orion/Kirkwood we've managed to keep reasonably up to date. One
difference with our system is that it boots directly from NOR flash (as
opposed to many Kirkwood implementations which make use of a
pre-bootloader to setup RAM).

Somewhere between v2015.04 and v2015.10 we started seeing a hang at
startup. I eventually tracked this down to the write to
twsi_control_flags which is putting the NOR flash into status mode
leading to the hang when the next instruction is executed.

I'm not sure how we haven't hit this before. In v2015.04 the same code
path is executed but somehow no hang occurs. This code hasn't changed
much between v2015.04 and v2015.10 and certainly not in any way that
would change this behaviour. Presumably _something_ else has changed in
a way that is affecting this behaviour but so far I haven't been able to
narrow this down to a particular change.


Chris Packham (1):
  i2c: mvtwsi: avoid writing to twsi_control_flags prior to relocation

 drivers/i2c/mvtwsi.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

-- 
2.8.2

             reply	other threads:[~2016-05-12  2:55 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-12  2:55 Chris Packham [this message]
2016-05-12  2:55 ` [U-Boot] [PATCH] i2c: mvtwsi: avoid writing to twsi_control_flags prior to relocation Chris Packham
2016-05-12  9:50   ` Stefan Roese
2016-05-12 22:35     ` Chris Packham
2016-05-13  1:20       ` Chris Packham
2016-05-13  5:49         ` Stefan Roese
2016-05-13  3:19       ` [U-Boot] [PATCH v2] i2c: mvtwsi: Eliminate twsi_control_flags Chris Packham

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