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List:       gentoo-embedded
Subject:    Re: [gentoo-embedded] Boot hangs on Soekris NET4801
From:       Ed W <lists () wildgooses ! com>
Date:       2014-12-29 16:45:57
Message-ID: 54A18545.7010609 () wildgooses ! com
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On 25/12/2014 22:24, Jean-Marc Beaune wrote:
> Hi,
>
> The boot process issue has been solved by setting up PATA properly in 
> the kernel config.
>

Just watch out, I *think* this will bite you again when you upgrade to a 
newer kernel? It's *NOT* the PATA which is the problem, but some 
bug/interaction between GPIO setup and the pata driver.  The key is 
actually to disable GPIO-Keys (from memory) which seems to break the 
pata module.  I think it only became a problem somewhere in the early 
3.x ish era where a platform module was added to emulate the Alix button 
as a "button".

Anyway, I don't recall the details now, but like you I briefly fixed it 
by fiddling with PATA modules before I realised it wasn't really the 
issue... I speculate it's something to do with the polling of the GPIOs 
which is leaving the structure in some state which breaks the PATA 
module...?

I haven't chased down details though.  I concede I have read the 
datasheets on the CS533x and mostly understand the basics of the 
interrupt setup, but I don't really understand enough about how linux 
deals with interrupts to resolve this..  My goal was to get GPIO 
interrupts working in order to get a GPS 1PPS working... I think I can 
concede I have mostly lost interest though and it's not going to get 
finished...  We do at least have platform setup modules for the various 
architectures though, so it's a start...

Good luck!

Ed W

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