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si(4) [netbsd man page]

SI(4)							   BSD Kernel Interfaces Manual 						     SI(4)

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

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scsi_transport(9F)                                         Kernel Functions for Drivers                                         scsi_transport(9F)

NAME
scsi_transport - request by a SCSI target driver to start a command SYNOPSIS
#include <sys/scsi/scsi.h> int scsi_transport(struct scsi_pkt *pkt); INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). PARAMETERS
pkt Pointer to a scsi_pkt(9S) structure. DESCRIPTION
Target drivers use scsi_transport() to request the host adapter driver to transport a command to the SCSI target device specified by pkt. The target driver must obtain resources for the packet using scsi_init_pkt(9F) prior to calling this function. The packet may be initial- ized using one of the makecom(9F) functions. scsi_transport() does not wait for the SCSI command to complete. See scsi_poll(9F) for a description of polled SCSI commands. Upon completion of the SCSI command the host adapter calls the completion routine provided by the target driver in the pkt_comp member of the scsi_pkt pointed to by pkt. RETURN VALUES
scsi_transport() returns: TRAN_ACCEPT The packet was accepted by the transport layer. TRAN_BUSY The packet could not be accepted because there was already a packet in progress for this target/lun, the host adapter queue was full, or the target device queue was full. TRAN_BADPKT The DMA count in the packet exceeded the DMA engine's maximum DMA size. TRAN_FATAL_ERROR A fatal error has occurred in the transport layer. CONTEXT
scsi_transport() can be called from user or interrupt context. EXAMPLES
Example 1: Using scsi_transport() if ((status = scsi_transport(rqpkt)) != TRAN_ACCEPT) { scsi_log(devp, sd_label, CE_WARN, "transport of request sense pkt fails (0x%x) ", status); } SEE ALSO
tran_start(9E), makecom(9F), scsi_init_pkt(9F), scsi_pktalloc(9F), scsi_poll(9F), scsi_pkt(9S) Writing Device Drivers SunOS 5.10 30 Aug 1995 scsi_transport(9F)
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