kern/83765: Adaptec 1542-CP requires plug-and-play switch setting

[Jason Bacon]

>Number:         83765
>Category:       kern
>Synopsis:       Adaptec 1542-CP requires plug-and-play switch setting
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          update
>Submitter-Id:   current-users
>Arrival-Date:   Wed Jul 20 04:00:34 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Jason Bacon
>Release:        FreeBSD 5.4-RELEASE i386
>Organization:
Medical College of Wisconsin
>Environment:
FreeBSD lisa.neuro.mcw.edu 5.4-RELEASE FreeBSD 5.4-RELEASE #0: Tue Jul  5 11:20:16 CDT 2005     root at lisa.neuro.mcw.edu:/usr/obj/usr/src/sys/lisa  i386
>Description:
	The Adaptec 1542-CP host adapter apparently does not function with
	the stock FreeBSD 5.x kernel unless the dip switches are set for 
	plug-and-play operation.  IT IS NOT SUFFICIENT TO ENABLE PLUG-AND-PLAY 
	IN THE ADAPTEC BIOS VIA CTRL+A AT BOOT TIME.  This is apparently
	contrary to 4.x kernels - I discovered this when upgrading an old system
	from 4.x to 5.x with a 1542-CP using static IO, IRQ and DMA
	values.  Fdisk complained that no disks were present.
	I tried various settings in the Adaptec BIOS config.  I managed to 
	get the disk recognized in the boot messages, but fdisk still could
	not find it.  Checking the manual revealed that one of the onboard dip
	switches toggles plug-and-play operation.  After flipping this switch,
	installation went forward with no hitches.
>How-To-Repeat:
	Try installing 5.x on a 1542-CP with PNP disabled via dip switches.
>Fix:
	Set dip switches on the 1542-CP for PNP.
>Release-Note:
>Audit-Trail:
>Unformatted: