sc(4) - NetBSD Manual Pages

SC(4)                   NetBSD Kernel Interfaces Manual                  SC(4)


NAME

     sc -- Sun Sun-2 SCSI bus host adaptor driver


SYNOPSIS

   sun2
     sc0 at mbmem0 addr 0x80000 ipl 2
     sc1 at mbmem0 addr 0x84000 ipl 2

   sun2 and sun4
     sc0 at vme0 addr 0x200000 irq 2 vec 0x40


DESCRIPTION

     The sc driver provides support for the Sun Microsystems "Sun-2" SCSI Bus
     Controller chipset found on various VME boards (Sun part #s 501-1045,
     501-1138, 501-1149, and 501-1167) and on the "Sun-2 SCSI/Serial" (Sun
     part # 501-1006) Multibus board.

     All versions of this driver can be configured with a flags directive in
     the config(1) file.  The values are bits in a bitfield, and are inter-
     preted as follows:

           0x0ff    Set bit (1<<target) to disable SCSI parity checking
           0x100    Set this bit to disable DMA interrupts (poll)
           0x200    Set this bit to disable DMA entirely (use PIO)

     For example: "flags 0x1ff" would disable DMA interrupts, and disable par-
     ity checking for targets 0-7.  The "target" is the SCSI ID number of a
     particular device on a particular SCSI bus.


SEE ALSO

     cd(4), ch(4), intro(4), scsi(4), sd(4), st(4)


AUTHORS

     Matt Fredette <fredette@NetBSD.org>,
     David Jones,
     Gordon Ross <gwr@NetBSD.org>,
     Adam Glass <glass@NetBSD.org>,
     Jason R. Thorpe <thorpej@NetBSD.org>.


BUGS

     This SCSI chipset is rumored to have bugs in its handling of SCSI parity,
     therefore it is recommended that you disable parity on all SCSI devices
     connected to this controller, and configure it with a 0x0ff value for its
     flags directive in the config(1) file.

     This chipset has no support for raising the ATN signal, so there is no
     way to ever schedule a MSG_OUT phase on the bus.  Currently, the driver
     will ultimately reset the bus if this phase is ever requested by the
     upper layer SCSI driver.

     This chipset has no support for SCSI disconnect/reselect.  This means
     that slow devices, such as tape drives, can hog, or "lock up" the SCSI
     bus.

     This driver has not been tested in combination with non-SCSI devices
     behind Emulex or Adaptec bridges, which are common in Sun 2s and in Sun
     Shoebox-type configurations.  These devices pre-date the SCSI-I spec, and
     might not behave the way the chipset code currently expects.

NetBSD 10.99                     June 28, 2001                    NetBSD 10.99