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Date: Mon, 14 Jun 2010 13:26:13 -0400 (EDT)
From: Nicolas Pitre <nico@fluxnic.net>
To: Mitch Bradley <wmb@firmworks.com>
Subject: Re: Request review of device tree documentation
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On Mon, 14 Jun 2010, Mitch Bradley wrote:

> First, the primary use case for "keeping OFW alive" is for debugging purposes.
> OFW remains resident in memory so that, if the OS is set to allow it (not the
> default), a hot-key freezes the OS and enters OFW, where a human can inspect
> the state of devices and OS data structures. A high skill level is required,
> so it's okay if some fiddling is necessary to find or establish virtual
> addresses or do similar magic .  

Why would you impose such pain on yourself in order to try to make OFW a 
viable debugging tool on ARM for live kernels, while you can achieve the 
same and more much less intrusively and so much more safely with a JTAG 
based debugger?

If the cost of a JTAG solution is a concern, you can order USB based 
JTAG dongles on the net for less than $30 and use them with OpenOCD[1].

Otherwise, what's wrong with already supported kgdb, or even kdb?

[1] http://openocd.berlios.de/web/


Nicolas