From owner-freebsd-current Sat Dec 27 22:26:37 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id WAA21632 for current-outgoing; Sat, 27 Dec 1997 22:26:37 -0800 (PST) (envelope-from owner-freebsd-current) Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id WAA21627 for ; Sat, 27 Dec 1997 22:26:30 -0800 (PST) (envelope-from grog@lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.8.7/8.8.5) with ESMTP id QAA09115; Sun, 28 Dec 1997 16:56:08 +1030 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.8.8/8.8.7) id QAA10459; Sun, 28 Dec 1997 16:56:07 +1030 (CST) (envelope-from grog) Message-ID: <19971228165606.13142@lemis.com> Date: Sun, 28 Dec 1997 16:56:06 +1030 From: Greg Lehey To: Chris Timmons Cc: Bruce Evans , julian@whistle.com, freebsd-current@FreeBSD.ORG Subject: Re: Remote gdb (was: no boot: config -g and options DDB) References: <19971228161844.52116@lemis.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.84e In-Reply-To: ; from Chris Timmons on Sat, Dec 27, 1997 at 10:06:09PM -0800 Organisation: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 WWW-Home-Page: http://www.lemis.com/~grog Sender: owner-freebsd-current@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk On Sat, Dec 27, 1997 at 10:06:09PM -0800, Chris Timmons wrote: > On Sun, 28 Dec 1997, Greg Lehey wrote: > >>> Are you sure it chooses the first sio with flags 0x10, or does the first >>> boot prompt get squirted out all eligible sio units? >> >> It's in sioncprobe(), the function for which Bruce supplied the >> patches. It goes out and looks for the first "enabled" console, does >> its thing and breaks out of the loop. Its thing includes setting the >> variable siocniobase, which is used by the other serial console >> routines to specify the output port. >> >> This stuff's pretty basic. Don't expect it to be clever enough to >> maintain the pressure in multiple pipes :-) > > Hmmm - well allow me to babble some more when I should instead be UTS. > > Is it the case then that flags 0x50 is presently just a hush for the > serial console (i.e. you have to have both flags on the same unit and > couldn't have sio0 with flags 0x10 and sio1 with flags 0x40 - preserving a > serial console at sio0 while debugging on sio1.) Well, I've never used the 0x40 bit. According to the documentation, it's for "Low-Level" serial communication, and it appears to work by not creating the device if it's specified. It might be the way that it was intended: boot with -h to set the serial hardware, and then disconnect the serial console again after the boot message. It does work, anyway. Bruce's patch makes more sense. > How would you start the debugger at boot on an sio with flags 0x40? > I remember seeing Bruce's commit messages about this so I can go > back and look. I've just tried it with flags 0x50, and it works fine. I still think it's a bit superfluous, but it would help protect the gdb port from other activities. Greg