i386/79350: "ata" unrequested increase in xDMAx speed due to channel reset

[Murray Baker]

>Number:         79350
>Category:       i386
>Synopsis:       "ata" unrequested increase in xDMAx speed due to channel reset
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-i386
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Mar 30 02:50:02 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Murray Baker
>Release:        5.3
>Organization:
>Environment:
FreeBSD daigomi.baker.lan 5.3-RELEASE FreeBSD 5.3-RELEASE #1: Mon Mar 28 17:13:02 EST 2005     root at daigomi.baker.lan:/usr/src/sys/i386/compile/DAIGOMI  i386

(5.3 with atapicam)
>Description:
      Various cd related operations cause an ata channel reset. This is
a problem if atacontrol has previously been used to set a slower xDMAx
speed, the original detected higher speed not working properly.

Attempting to mount_cd9660 a defective or incompatible media can do
this. So will "atacontrol reinit" or "camcontrol reset".

>How-To-Repeat:
      Can be demonstrated as follows...
atacontrol mode 1
Master = UDMA33
Slave  = UDMA66
atacontrol mode 1 UDMA33 UDMA33
Master = UDMA33
Slave  = UDMA33
camcontrol reset 1              (or atacontrol reinit 1)
Reset of bus 1 was successful
atacontrol mode 1
Master = UDMA33
Slave  = UDMA66
>Fix:
      
>Release-Note:
>Audit-Trail:
>Unformatted: