written from a reading of config files and driver source code
Erik E. Fair <fair (at] NetBSD.org>
.Dd May 7, 1998 .Dt SI 4 .Os .Sh NAME .Nm si , .Nm sw .Nd NCR 5380 SCSI bus host adaptor driver .Sh SYNOPSIS .Ss sun3 .Cd "si0 at obio0 addr 0x140000 ipl 2" .Ss sun3 and sun3x .Cd "si0 at vme2 addr 0x200000 ipl 2 vect 0x40" .Cd "si1 at vme2 addr 0x204000 ipl 2 vect 0x41" .Ss sun3/E .Cd "sebuf0 at vme2 addr 0x300000 ipl 2 vect 0x74 # and 0x75" .Cd "sebuf1 at vme2 addr 0x340000 ipl 2 vect 0x76 # and 0x77" .Cd "si* at sebuf?" .Ss sun4 and sun2 .Cd "si0 at vme0 addr 0x200000 pri 2 vec 0x40" .Ss sun4/100 .Cd "sw0 at obio0 addr 0x0a000000 level 3" .Sh DESCRIPTION The .Nm and .Nm sw .Qq Tn SCSI Weird drivers provide support for the .Tn NCR 5380 .Tn SCSI Bus Controller (SBC) chip found on various Sun Microsystems .Tn CPU motherboards (obio), and on the .Qq Sun-3 VME SCSI
q Sun part # 501-1236 board used in systems with .Tn VME bus. .Ss sun3 and sun3x The .Tn sun3 and .Tn sun3x version of this driver can be configured with a .Em flags directive in the .Xr config 1 file. The values are bits in a bitfield, and are interpreted as follows:
p l -tag -offset indent -compact -width 0x000ff t 0x000ff Set bit (1<<target) to disable .Tn SCSI disconnect/reselect t 0x0ff00 Set bit (1<<(target+8)) to disable .Tn SCSI parity checking t 0x10000 Set this bit to disable .Tn DMA interrupts (poll) t 0x20000 Set this bit to disable .Tn DMA entirely (use PIO) .El
p For example: .Qq flags 0x1000f would disable .Tn DMA interrupts, and disable disconnect/reselect for targets 0-3. The .Qq target is the .Tn SCSI ID number of a particular device on a particular .Tn SCSI bus. .Ss sun4 The .Tn sun4 version of this driver can also be configured with a .Em flags directive in the .Xr config 1 file. The values are bits in a bitfield, and are interpreted as follows:
p l -tag -offset indent -compact -width 0x01 t 0x01 Use .Tn DMA
q may be polled t 0x02 Use .Tn DMA completion interrupts t 0x04 Allow .Tn SCSI disconnect/reselect .El
p For example: .Qq flags 0x07 would enable .Tn DMA , interrupts, and reselect. By default, .Tn DMA is enabled in the .Tn sun4 driver. .Sh SEE ALSO .Xr cd 4 , .Xr ch 4 , .Xr intro 4 , .Xr scsi 4 , .Xr sd 4 , .Xr st 4 .Sh AUTHORS David Jones, .An Gordon Ross .Aq gwr (at] NetBSD.org , .An Adam Glass .Aq glass (at] NetBSD.org , .An Jason R. Thorpe .Aq thorpej (at] NetBSD.org . .Sh BUGS The .Tn VME variant has a bit to enable or disable the .Tn DMA engine, but that bit also gates the interrupt line from the .Tn NCR5380
q !! . Therefore, in order to get any interrupt from the .Tn NCR5380 , (i.e. for reselect) one must clear the .Tn DMA engine transfer count and then enable .Tn DMA . This has the further complication that you CAN NOT touch the .Tn NCR5380 while the .Tn DMA enable bit is set, so we have to turn .Tn DMA back off before we even look at the .Tn NCR5380 .
p Support for the Sun 4/100 .Nm sw .Qq Tn SCSI Weird is not complete. .Tn DMA works, but interrupts (and, thus, reselection) don't for reasons unknown. Further progress has halted pending the availability of a machine for testing.
p .Tn DMA , .Tn DMA completion interrupts, and reselection work fine on a Sun 4/260 with modern .Tn SCSI-II disks attached. There have been reports of reselection failing on .Tn Sun Shoebox-type configurations where there are multiple non-SCSI devices behind .Tn Emulex or .Tn Adaptec bridges. These devices pre-date the .Tn SCSI-I spec, and might not behave the way the NCR5380 code expects. For this reason, only .Tn DMA is enabled by default in the .Tn sun4 driver.
Indexes created Tue Sep 23 02:09:52 GMT 2025