1.\" $NetBSD: sc.4,v 1.5 2002/02/13 08:17:45 ross Exp $ 2.\" 3.\" written from a reading of config files and driver source code 4.\" Erik E. Fair <fair@netbsd.org> 5.\" Matt Fredette <fredette@netbsd.org> 6.Dd June 28, 2001 7.Dt SC 4 8.Os 9.Sh NAME 10.Nm sc 11.Nd Sun Sun-2 SCSI bus host adaptor driver 12.Sh SYNOPSIS 13.Ss sun2 14.Cd "sc0 at mbmem0 addr 0x80000 ipl 2" 15.Cd "sc1 at mbmem0 addr 0x84000 ipl 2" 16.Ss sun2 and sun4 17.Cd "sc0 at vme0 addr 0x200000 irq 2 vec 0x40" 18.Sh DESCRIPTION 19The 20.Nm 21driver provides support for the 22Sun Microsystems 23.Qq Sun-2 24.Tn SCSI 25Bus Controller chipset found on various 26VME boards 27.Pq Sun part #s 501-1045, 501-1138, 501-1149, and 501-1167 28and on the 29.Qq Sun-2 SCSI/Serial 30.Pq Sun part # 501-1006 31Multibus board. 32.Pp 33All 34versions of this driver can be configured with a 35.Em flags 36directive in the 37.Xr config 8 38file. 39The values are bits in a bitfield, and are interpreted as follows: 40.Pp 41.Bl -tag -offset indent -compact -width 0x000ff 42.It 0x0ff 43Set bit (1\*[Lt]\*[Lt]target) to disable 44.Tn SCSI 45parity checking 46.It 0x100 47Set this bit to disable 48.Tn DMA 49interrupts (poll) 50.It 0x200 51Set this bit to disable 52.Tn DMA 53entirely (use PIO) 54.El 55.Pp 56For example: 57.Qq flags 0x1ff 58would disable 59.Tn DMA 60interrupts, and disable parity checking for targets 0-7. 61The 62.Qq target 63is the 64.Tn SCSI 65ID number of a particular device on a particular 66.Tn SCSI 67bus. 68.Sh SEE ALSO 69.Xr cd 4 , 70.Xr ch 4 , 71.Xr intro 4 , 72.Xr scsi 4 , 73.Xr sd 4 , 74.Xr st 4 75.Sh AUTHORS 76Matt Fredette, 77.Aq fredette@netbsd.org , 78.br 79David Jones, 80.br 81Gordon Ross 82.Aq gwr@netbsd.org , 83.br 84Adam Glass 85.Aq glass@netbsd.org , 86.br 87Jason R. Thorpe 88.Aq thorpej@netbsd.org . 89.Sh BUGS 90This 91.Tn SCSI 92chipset is rumored to have bugs in its handling of 93.Tn SCSI 94parity, therefore it is recommended that you disable parity 95on all 96.Tn SCSI 97devices connected to this controller, and configure it with 98a 990x0ff 100value for its 101.Em flags 102directive in the 103.Xr config 8 104file. 105.Pp 106This 107chipset has no support for raising the 108.Tn ATN 109signal, so there is no way to ever schedule a 110.Tn MSG_OUT 111phase on the bus. Currently, the driver will ultimately 112reset the bus if this phase is ever requested by the upper 113layer 114.Tn SCSI 115driver. 116.Pp 117This chipset has no support for 118.Tn SCSI 119disconnect/reselect. This means that slow devices, 120such as tape drives, can hog, or 121.Qq lock up 122the SCSI bus. 123.Pp 124This driver has not been tested in combination with 125non-SCSI devices behind 126.Tn Emulex 127or 128.Tn Adaptec 129bridges, which are common in 130.Tn Sun 1312s and in 132.Tn Sun 133Shoebox-type configurations. 134These devices pre-date the 135.Tn SCSI-I 136spec, and might not behave the way the chipset code currently expects. 137