Subject: Re: install/34280: cannot boot install media via serial
To: None <,,>
From: George Georgalis <>
List: netbsd-bugs
Date: 08/29/2006 19:25:03
The following reply was made to PR install/34280; it has been noted by GNATS.

From: George Georgalis <>
To:, Martin Husemann <>,
	David Laight <>, Pavel Cahyna <>,
	Manuel Bouyer <>
Subject: Re: install/34280: cannot boot install media via serial
Date: Tue, 29 Aug 2006 15:20:40 -0400

 Summary followup of, to date, all on/off list responses...
 Looking at cvsweb I see:
 The netbsd-3 GENERIC kernel is configured for CONADDR=0x2f8,CONSPEED=57600
 While netbsd-3 INSTALL kernel is configured for CONADDR=0x3f8,CONSPEED=9600
 Presumably those are defaults -- the option lines are commented
 out in the conf, cf:
 for the hardware in question, bios serial defaults are
 COM1 (3f8h,irq4)
 COM2 (2f8h,irq3)  
 and serial port speed setting 57600
 Exactly one serial port is physically available and review of
 netbsd-3-0-RELEASE i386 INSTALL dmesg (photograph of 'more
 /kern/msgbuf' within the 3.0 usb cdrom installer) indicates
 the following is detected (I don't know what ns16550a means)
 com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
 com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo
 Clearly there is an off by one port counting in kernel space
 vs bios, just to confuse matters -- so I'll refer to the
 address whenever possible, also 'COM' for bios and 'com' for
 kernel numbering.
 The default physical port available is 2f8h (bios COM2), that
 address can be changed.
 On prior attempts I configured bios console on COM2 with a speed
 of 115200, noting that a minicom speed mismatch yields zero serial
 data, here's a table of prior attempts:
 bios redirection to COM1(0x3f8), zero bios serial
 bios redirection to COM2(0x2f8), consdev com0, zero serial
 bios redirection to COM2(0x2f8), consdev com1, zero serial
 bios redirection to COM2(0x2f8), consdev com2, serial till checksum
 the partial success with "consdev com2" indicates bios serial
 port numbering at the boot prompt.
 On Fri, Aug 25, 2006 at 04:18:38PM -0400, George Georgalis wrote:
 > On another USB only amd64 with an otherwise working install,
 > com1 is the available serial port, and it does the same thing...
 > boots to VGA after checksum to serial.
 On that Sun X2100, that's "bios COM1", an amd64 3.1_RC1
 NetBSD 3.1_RC1 (GENERIC) #0: Sun Aug 20 22:47:46 UTC 2006
 install detect only:
 com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
 A minicom speed mismatch could explain serial fail after checksum.
 Is it possible for the kernel to pickup the serial port speed as a
 hand-off from bios?
 Now, I've set bios/minicom speed to the apparent INSTALLER
 default, 9600, that yields complete garbage in serial console
 through bios and into boot prompt, below is the end of the
 session, I'm entering "consdev 2" then "boot"
 > _+ 2                                                                        
 +#+ _+ +.                                                                   
 > +                                                                           
 +ű 0#:+_                                                                   
 serial cleans up for checksum then stops like before.
 What else can I try?
 // George
 George Georgalis, Information Systems Scientist, Metrum Research Group
 2 Tunxis Road, Suite 112, Tariffville, CT 06081; direct: 860.670.4346