From owner-freebsd-hackers@freebsd.org  Fri Nov 24 15:09:28 2017
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From: "Rodney W. Grimes" <freebsd-rwg@pdx.rh.CN85.dnsmgr.net>
Message-Id: <201711241509.vAOF9K43095978@pdx.rh.CN85.dnsmgr.net>
Subject: Re: Is ddb(4) over a USB-to-Serial port possible?
In-Reply-To: <953998da-5e3a-1f3c-b56b-41ddda020b68@selasky.org>
To: Hans Petter Selasky <hps@selasky.org>
Date: Fri, 24 Nov 2017 07:09:20 -0800 (PST)
CC: Oliver Pinter <oliver.pinter@hardenedbsd.org>,
 "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>,
 Farhan Khan <khanzf@gmail.com>
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> On 11/23/17 23:34, Oliver Pinter wrote:
> > Could we somehow change these after attached device?  Ergo could we setup
> > two USB context, one for normal operation and one for the debugger?
> 
> What you can do is to set the values, then re-enumerate the USB device 
> like this:
> 
> usbconfig -d X.Y reset

It would be absolutely wonderful if someone would add a page to
the handbook near the current page on ddb on how to do ddb
over serial, both uart and usb based.

There is also some very minor discussion of ddb over serial
in the HINTS section of ddb(4) that could include these
nice little tid bits about how to get it working over a
usb device.

Since uarts have all but disappeared for modern PC designs this
is becoming more important.

Thanks,
-- 
Rod Grimes                                                 rgrimes@freebsd.org