Subject: Re: install/34280: cannot boot install media via serial
To: None <,,>
From: David Laight <>
List: netbsd-bugs
Date: 08/26/2006 08:05:08
The following reply was made to PR install/34280; it has been noted by GNATS.

From: David Laight <>
Subject: Re: install/34280: cannot boot install media via serial
Date: Sat, 26 Aug 2006 09:03:40 +0100

 On Fri, Aug 25, 2006 at 10:15:11PM +0000, Pavel Cahyna wrote:
 >  com2? what is the IRQ and I/O port for this?
 >  I think you could add the device in userconf (boot -c).
 Unlikely - that is kernel code, so is using the console.
 You need to get the kernel console out going to the device, this has
 to happen before the autoconf framework runs.
 Possibly the 'btinfo' structure could (maybe it does) carry the i/o
 port assignment for the console.
 If your bios is doing 'console redirection' making to the VGA appear on
 a serial port, you want to get the boot code to switch to natively
 use the serial port before entering the kernel.  That way you stand
 a chance of the kernel using the serial port properly.
 However it must be a 16550 style UART, not some USB wizardry.
 You might find it easiest to PXE boot the install kernel.
 Use 'installboot -e -o console=com2,speed=0 /usr/mdec/pxeboot_amd64.bin'
 to modify the pxeboot program to use com2.
 (It reads the io port value from BIOS memory)
 David Laight: