path: root/sys/dev/aic7xxx/aic7xxx.reg

/*
 * Aic7xxx register and scratch ram definitions.
 *
 * Copyright (c) 1994, 1995, 1996, 1997 Justin T. Gibbs.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice immediately at the beginning of the file, without modification,
 *    this list of conditions, and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	$Id: aic7xxx.reg,v 1.2 1997/04/14 02:26:56 gibbs Exp $
 */

/*
 * This file is processed by the aic7xxx_asm utility for use in assembling
 * firmware for the aic7xxx family of SCSI host adapters as well as to generate
 * a C header file for use in the kernel portion of the Aic7xxx driver.
 *
 * All page numbers refer to the Adaptec AIC-7770 Data Book available from
 * Adaptec's Technical Documents Department 1-800-934-2766
 */

/*
 * SCSI Sequence Control (p. 3-11).
 * Each bit, when set starts a specific SCSI sequence on the bus
 */
register SCSISEQ {
	address			0x000
	access_mode RW
	bit	TEMODE		0x80
	bit	ENSELO		0x40
	bit	ENSELI		0x20
	bit	ENRSELI		0x10
	bit	ENAUTOATNO	0x08
	bit	ENAUTOATNI	0x04
	bit	ENAUTOATNP	0x02
	bit	SCSIRSTO	0x01
}

/*
 * SCSI Transfer Control 0 Register (pp. 3-13).
 * Controls the SCSI module data path.
 */
register SXFRCTL0 {
	address			0x001
	access_mode RW
	bit	DFON		0x80
	bit	DFPEXP		0x40
	bit	FAST20		0x20
	bit	CLRSTCNT	0x10
	bit	SPIOEN		0x08
	bit	SCAMEN		0x04
	bit	CLRCHN		0x02
}

/*
 * SCSI Transfer Control 1 Register (pp. 3-14,15).
 * Controls the SCSI module data path.
 */
register SXFRCTL1 {
	address			0x002
	access_mode RW
	bit	BITBUCKET	0x80
	bit	SWRAPEN		0x40
	bit	ENSPCHK		0x20
	mask	STIMESEL	0x18
	bit	ENSTIMER	0x04
	bit	ACTNEGEN	0x02
	bit	STPWEN		0x01	/* Powered Termination */
}

/*
 * SCSI Control Signal Read Register (p. 3-15).
 * Reads the actual state of the SCSI bus pins
 */
register SCSISIGI {
	address			0x003
	access_mode RO
	bit	CDI		0x80
	bit	IOI		0x40
	bit	MSGI		0x20
	bit	ATNI		0x10
	bit	SELI		0x08
	bit	BSYI		0x04
	bit	REQI		0x02
	bit	ACKI		0x01
/*
 * Possible phases in SCSISIGI
 */
	mask	PHASE_MASK	CDI|IOI|MSGI
	mask	P_DATAOUT	0x00
	mask	P_DATAIN	IOI
	mask	P_COMMAND	CDI
	mask	P_MESGOUT	CDI|MSGI
	mask	P_STATUS	CDI|IOI
	mask	P_MESGIN	CDI|IOI|MSGI
}

/*
 * SCSI Control Signal Write Register (p. 3-16).
 * Writing to this register modifies the control signals on the bus.  Only
 * those signals that are allowed in the current mode (Initiator/Target) are
 * asserted.
 */
register SCSISIGO {
	address			0x003
	access_mode WO
	bit	CDO		0x80
	bit	IOO		0x40
	bit	MSGO		0x20
	bit	ATNO		0x10
	bit	SELO		0x08
	bit	BSYO		0x04
	bit	REQO		0x02
	bit	ACKO		0x01
/*
 * Possible phases to write into SCSISIG0
 */
	mask	PHASE_MASK	CDI|IOI|MSGI
	mask	P_DATAOUT	0x00
	mask	P_DATAIN	IOI
	mask	P_COMMAND	CDI
	mask	P_MESGOUT	CDI|MSGI
	mask	P_STATUS	CDI|IOI
	mask	P_MESGIN	CDI|IOI|MSGI
}

/* 
 * SCSI Rate Control (p. 3-17).
 * Contents of this register determine the Synchronous SCSI data transfer
 * rate and the maximum synchronous Req/Ack offset.  An offset of 0 in the
 * SOFS (3:0) bits disables synchronous data transfers.  Any offset value
 * greater than 0 enables synchronous transfers.
 */
register SCSIRATE {
	address			0x004
	access_mode RW
	bit	WIDEXFER	0x80		/* Wide transfer control */
	mask	SXFR		0x70		/* Sync transfer rate */
	mask	SOFS		0x0f		/* Sync offset */
}

/*
 * SCSI ID (p. 3-18).
 * Contains the ID of the board and the current target on the
 * selected channel.
 */
register SCSIID	{
	address			0x005
	access_mode RW
	mask	TID		0xf0		/* Target ID mask */
	mask	OID		0x0f		/* Our ID mask */
}

/*
 * SCSI Latched Data (p. 3-19).
 * Read/Write latches used to transfer data on the SCSI bus during
 * Automatic or Manual PIO mode.  SCSIDATH can be used for the
 * upper byte of a 16bit wide asynchronouse data phase transfer.
 */
register SCSIDATL {
	address			0x006
	access_mode RW
}

register SCSIDATH {
	address			0x007
	access_mode RW
}

/*
 * SCSI Transfer Count (pp. 3-19,20)
 * These registers count down the number of bytes transferred
 * across the SCSI bus.  The counter is decremented only once
 * the data has been safely transferred.  SDONE in SSTAT0 is
 * set when STCNT goes to 0
 */ 
register STCNT {
	address			0x008
	size	3
	access_mode RW
}

/*
 * Clear SCSI Interrupt 0 (p. 3-20)
 * Writing a 1 to a bit clears the associated SCSI Interrupt in SSTAT0.
 */
register CLRSINT0 {
	address			0x00b
	access_mode WO
	bit	CLRSELDO	0x40
	bit	CLRSELDI	0x20
	bit	CLRSELINGO	0x10
	bit	CLRSWRAP	0x08
	bit	CLRSPIORDY	0x02
}

/*
 * SCSI Status 0 (p. 3-21)
 * Contains one set of SCSI Interrupt codes
 * These are most likely of interest to the sequencer
 */
register SSTAT0	{
	address			0x00b
	access_mode RO
	bit	TARGET		0x80		/* Board acting as target */
	bit	SELDO		0x40		/* Selection Done */
	bit	SELDI		0x20		/* Board has been selected */
	bit	SELINGO		0x10		/* Selection In Progress */
	bit	SWRAP		0x08		/* 24bit counter wrap */
	bit	SDONE		0x04		/* STCNT = 0x000000 */
	bit	SPIORDY		0x02		/* SCSI PIO Ready */
	bit	DMADONE		0x01		/* DMA transfer completed */
}

/*
 * Clear SCSI Interrupt 1 (p. 3-23)
 * Writing a 1 to a bit clears the associated SCSI Interrupt in SSTAT1.
 */
register CLRSINT1 {
	address			0x00c
	access_mode WO
	bit	CLRSELTIMEO	0x80
	bit	CLRATNO		0x40
	bit	CLRSCSIRSTI	0x20
	bit	CLRBUSFREE	0x08
	bit	CLRSCSIPERR	0x04
	bit	CLRPHASECHG	0x02
	bit	CLRREQINIT	0x01
}

/*
 * SCSI Status 1 (p. 3-24)
 */
register SSTAT1	{
	address			0x00c
	access_mode RO
	bit	SELTO		0x80
	bit	ATNTARG 	0x40
	bit	SCSIRSTI	0x20
	bit	PHASEMIS	0x10
	bit	BUSFREE		0x08
	bit	SCSIPERR	0x04
	bit	PHASECHG	0x02
	bit	REQINIT		0x01
}

/*
 * SCSI Status 2 (pp. 3-25,26)
 */
register SSTAT2 {
	address			0x00d
	access_mode RO
	bit	OVERRUN		0x80
	mask	SFCNT		0x1f
}

/*
 * SCSI Status 3 (p. 3-26)
 */
register SSTAT3 {
	address			0x00e
	access_mode RO
	mask	SCSICNT		0xf0
	mask	OFFCNT		0x0f
}

/*
 * SCSI Test Control (p. 3-27)
 */
register SCSITEST {
	address			0x00f
	access_mode RW
	bit	RQAKCNT		0x04
	bit	CNTRTEST	0x02
	bit	CMODE		0x01
}

/*
 * SCSI Interrupt Mode 1 (p. 3-28)
 * Setting any bit will enable the corresponding function
 * in SIMODE0 to interrupt via the IRQ pin.
 */
register SIMODE0 {
	address			0x010
	access_mode RW
	bit	ENSELDO		0x40
	bit	ENSELDI		0x20
	bit	ENSELINGO	0x10
	bit	ENSWRAP		0x08
	bit	ENSDONE		0x04
	bit	ENSPIORDY	0x02
	bit	ENDMADONE	0x01
}

/*
 * SCSI Interrupt Mode 1 (pp. 3-28,29)
 * Setting any bit will enable the corresponding function
 * in SIMODE1 to interrupt via the IRQ pin.
 */
register SIMODE1 {
	address			0x011
	access_mode RW
	bit	ENSELTIMO	0x80
	bit	ENATNTARG	0x40
	bit	ENSCSIRST	0x20
	bit	ENPHASEMIS	0x10
	bit	ENBUSFREE	0x08
	bit	ENSCSIPERR	0x04
	bit	ENPHASECHG	0x02
	bit	ENREQINIT	0x01
}

/*
 * SCSI Data Bus (High) (p. 3-29)
 * This register reads data on the SCSI Data bus directly.
 */
register SCSIBUSL {
	address			0x012
	access_mode RO
}

register SCSIBUSH {
	address			0x013
	access_mode RO
}

/*
 * SCSI/Host Address (p. 3-30)
 * These registers hold the host address for the byte about to be
 * transferred on the SCSI bus.  They are counted up in the same
 * manner as STCNT is counted down.  SHADDR should always be used
 * to determine the address of the last byte transferred since HADDR
 * can be skewed by write ahead.
 */
register SHADDR {
	address			0x014
	size	4
	access_mode RO
}

/*
 * Selection Timeout Timer (p. 3-30)
 */
register SELTIMER {
	address			0x018
	access_mode RW
	bit	STAGE6		0x20
	bit	STAGE5		0x10
	bit	STAGE4		0x08
	bit	STAGE3		0x04
	bit	STAGE2		0x02
	bit	STAGE1		0x01
}

/*
 * Selection/Reselection ID (p. 3-31)
 * Upper four bits are the device id.  The ONEBIT is set when the re/selecting
 * device did not set its own ID.
 */
register SELID {
	address			0x019
	access_mode RW
	mask	SELID_MASK	0xf0
	bit	ONEBIT		0x08
}

/*
 * SCSI Block Control (p. 3-32)
 * Controls Bus type and channel selection.  In a twin channel configuration
 * addresses 0x00-0x1e are gated to the appropriate channel based on this
 * register.  SELWIDE allows for the coexistence of 8bit and 16bit devices
 * on a wide bus.
 */
register SBLKCTL {
	address			0x01f
	access_mode RW
	bit	DIAGLEDEN	0x80	/* Aic78X0 only */
	bit	DIAGLEDON	0x40	/* Aic78X0 only */
	bit	AUTOFLUSHDIS	0x20
	bit	SELBUSB		0x08
	bit	SELWIDE		0x02
}

/*
 * Sequencer Control (p. 3-33)
 * Error detection mode and speed configuration
 */
register SEQCTL {
	address			0x060
	access_mode RW
	bit	PERRORDIS	0x80
	bit	PAUSEDIS	0x40
	bit	FAILDIS		0x20
	bit	FASTMODE	0x10
	bit	BRKADRINTEN	0x08
	bit	STEP		0x04
	bit	SEQRESET	0x02
	bit	LOADRAM		0x01
}

/*
 * Sequencer RAM Data (p. 3-34)
 * Single byte window into the Scratch Ram area starting at the address
 * specified by SEQADDR0 and SEQADDR1.  To write a full word, simply write
 * four bytes in sucessesion.  The SEQADDRs will increment after the most
 * significant byte is written
 */
register SEQRAM {
	address			0x061
	access_mode RW
}

/*
 * Sequencer Address Registers (p. 3-35)
 * Only the first bit of SEQADDR1 holds addressing information
 */
register SEQADDR0 {
	address			0x062
	access_mode RW
}

register SEQADDR1 {
	address			0x063
	access_mode RW
	mask	SEQADDR1_MASK	0x01
}

/*
 * Accumulator
 * We cheat by passing arguments in the Accumulator up to the kernel driver
 */
register ACCUM {
	address			0x064
	access_mode RW
	accumulator
}

register SINDEX	{
	address			0x065
	access_mode RW
	sindex
}

register DINDEX {
	address			0x066
	access_mode RW
}

register ALLONES {
	address			0x069
	access_mode RO
	allones
}

register ALLZEROS {
	address			0x06a
	access_mode RO
	allzeros
}

register NONE {
	address			0x06a
	access_mode WO
	none
}

register FLAGS {
	address			0x06b
	access_mode RO
	bit	ZERO		0x02
	bit	CARRY		0x01
}

register SINDIR	{
	address			0x06c
	access_mode RO
}

register DINDIR	 {
	address			0x06d
	access_mode WO
}

register FUNCTION1 {
	address			0x06e
	access_mode RW
}

register STACK {
	address			0x06f
	access_mode RO
}

/*
 * Board Control (p. 3-43)
 */
register BCTL {
	address			0x084
	access_mode RW
	bit	ACE		0x08
	bit	ENABLE		0x01
}

/*
 * On the aic78X0 chips, Board Control is replaced by the DSCommand
 * register (p. 4-64)
 */
register DSCOMMAND {
	address			0x084
	access_mode RW
	bit	CACHETHEN	0x80	/* Cache Threshold enable */
	bit	DPARCKEN	0x40	/* Data Parity Check Enable */
	bit	MPARCKEN	0x20	/* Memory Parity Check Enable */
	bit	EXTREQLCK	0x10	/* External Request Lock */
}

/*
 * Bus On/Off Time (p. 3-44)
 */
register BUSTIME {
	address			0x085
	access_mode RW
	mask	BOFF		0xf0
	mask	BON		0x0f
}

/*
 * Bus Speed (p. 3-45)
 */
register BUSSPD {
	address			0x086
	access_mode RW
	mask	DFTHRSH		0xc0
	mask	STBOFF		0x38
	mask	STBON		0x07
	mask	DFTHRSH_100	0xc0
}

/*
 * Host Control (p. 3-47) R/W
 * Overall host control of the device.
 */
register HCNTRL {
	address			0x087
	access_mode RW
	bit	POWRDN		0x40
	bit	SWINT		0x10
	bit	IRQMS		0x08
	bit	PAUSE		0x04
	bit	INTEN		0x02
	bit	CHIPRST		0x01
	bit	CHIPRSTACK	0x01
}

/*
 * Host Address (p. 3-48)
 * This register contains the address of the byte about
 * to be transferred across the host bus.
 */
register HADDR {
	address			0x088
	size	4
	access_mode RW
}

register HCNT {
	address			0x08c
	size	3
	access_mode RW
}

/*
 * SCB Pointer (p. 3-49)
 * Gate one of the four SCBs into the SCBARRAY window.
 */
register SCBPTR {
	address			0x090
	access_mode RW
}

/*
 * Interrupt Status (p. 3-50)
 * Status for system interrupts
 */
register INTSTAT {
	address			0x091
	access_mode RW
	bit	BRKADRINT 0x08
	bit	SCSIINT	  0x04
	bit	CMDCMPLT  0x02
	bit	SEQINT    0x01
	mask	BAD_PHASE	SEQINT		/* unknown scsi bus phase */
	mask	SEND_REJECT	0x10|SEQINT	/* sending a message reject */
	mask	NO_IDENT	0x20|SEQINT	/* no IDENTIFY after reconnect*/
	mask	NO_MATCH	0x30|SEQINT	/* no cmd match for reconnect */
	mask	EXTENDED_MSG	0x40|SEQINT	/* Extended message received */
	mask	NO_MATCH_BUSY	0x50|SEQINT	/* Couldn't find BUSY SCB */
	mask	REJECT_MSG	0x60|SEQINT	/* Reject message received */
	mask	BAD_STATUS	0x70|SEQINT	/* Bad status from target */
	mask	RESIDUAL	0x80|SEQINT	/* Residual byte count != 0 */
	mask	ABORT_CMDCMPLT	0x91		/*
						 * Command tagged for abort
						 * completed successfully.
						 */
	mask	AWAITING_MSG	0xa0|SEQINT	/*
						 * Kernel requested to specify
                                                 * a message to this target
                                                 * (command was null), so tell
                                                 * it that it can fill the
                                                 * message buffer.
                                                 */
	mask	MSG_BUFFER_BUSY	0xc0|SEQINT	/*
						 * Sequencer wants to use the
						 * message buffer, but it
						 * already contains a message
						 */
	mask	MSGIN_PHASEMIS	0xd0|SEQINT	/*
						 * Target changed phase on us
						 * when we were expecting
						 * another msgin byte.
						 */
	mask	DATA_OVERRUN	0xe0|SEQINT	/*
						 * Target attempted to write
						 * beyond the bounds of its
						 * command.
						 */

	mask	SEQINT_MASK	0xf0|SEQINT	/* SEQINT Status Codes */
	mask	INT_PEND  (BRKADRINT|SEQINT|SCSIINT|CMDCMPLT)
}

/*
 * Hard Error (p. 3-53)
 * Reporting of catastrophic errors.  You usually cannot recover from
 * these without a full board reset.
 */
register ERROR {
	address			0x092
	access_mode RO
	bit	PARERR		0x08
	bit	ILLOPCODE	0x04
	bit	ILLSADDR	0x02
	bit	ILLHADDR	0x01
}

/*
 * Clear Interrupt Status (p. 3-52)
 */
register CLRINT {
	address			0x092
	access_mode WO
	bit	CLRBRKADRINT	0x08
	bit	CLRSCSIINT      0x04
	bit	CLRCMDINT 	0x02
	bit	CLRSEQINT 	0x01
}

register DFCNTRL {
	address			0x093
	access_mode RW
	bit	WIDEODD		0x40
	bit	SCSIEN		0x20
	bit	SDMAEN		0x10
	bit	SDMAENACK	0x10
	bit	HDMAEN		0x08
	bit	HDMAENACK	0x08
	bit	DIRECTION	0x04
	bit	FIFOFLUSH	0x02
	bit	FIFORESET	0x01
}

register DFSTATUS {
	address			0x094
	access_mode RO
	bit	DWORDEMP	0x20
	bit	MREQPEND	0x10
	bit	HDONE		0x08
	bit	DFTHRESH	0x04
	bit	FIFOFULL	0x02
	bit	FIFOEMP		0x01
}

register DFDAT {
	address			0x099
	access_mode RW
}

/*
 * SCB Auto Increment (p. 3-59)
 * Byte offset into the SCB Array and an optional bit to allow auto
 * incrementing of the address during download and upload operations
 */
register SCBCNT {
	address			0x09a
	access_mode RW
	bit	SCBAUTO		0x80
	mask	SCBCNT_MASK	0x1f
}

/*
 * Queue In FIFO (p. 3-60)
 * Input queue for queued SCBs (commands that the seqencer has yet to start)
 */
register QINFIFO {
	address			0x09b
	access_mode RW
}

/*
 * Queue In Count (p. 3-60)
 * Number of queued SCBs
 */
register QINCNT	{
	address			0x09c
	access_mode RO
}

/*
 * Queue Out FIFO (p. 3-61)
 * Queue of SCBs that have completed and await the host
 */
register QOUTFIFO {
	address			0x09d
	access_mode WO
}

/*
 * Queue Out Count (p. 3-61)
 * Number of queued SCBs in the Out FIFO
 */
register QOUTCNT {
	address			0x09e
	access_mode RO
}

/*
 * SCB Definition (p. 5-4)
 */
scb {
	address			0x0a0
	SCB_CONTROL {
		size	1
		bit	MK_MESSAGE      0x80
		bit	DISCENB         0x40
		bit	TAG_ENB		0x20
		bit	MUST_DMAUP_SCB	0x10
		bit	ABORT_SCB	0x08
		bit	DISCONNECTED	0x04
		mask	SCB_TAG_TYPE	0x03
	}
	SCB_TCL {
		size	1
		bit	SELBUSB		0x08
		mask	TID		0xf0
		mask	LID		0x07
	}
	SCB_TARGET_STATUS {
		size	1
	}
	SCB_SGCOUNT {
		size	1
	}
	SCB_SGPTR {
		size	4
	}
	SCB_RESID_SGCNT {
		size	1
	}
	SCB_RESID_DCNT	{
		size	3
	}
	SCB_DATAPTR {
		size	4
	}
	SCB_DATACNT {
		size	3
	}
	SCB_LINKED_NEXT {
		size	1
	}
	SCB_CMDPTR {
		size	4
	}
	SCB_CMDLEN {
		size	1
	}
	SCB_TAG {
		size	1
	}
	SCB_NEXT {
		size	1
	}
	SCB_PREV {
		size	1
	}
	SCB_BUSYTARGETS {
		size	4
	}
}

const	SG_SIZEOF	0x08		/* sizeof(struct ahc_dma) */

/* --------------------- AHA-2840-only definitions -------------------- */

register SEECTL_2840 {
	address			0x0c0
	access_mode RW
	bit	CS_2840		0x04
	bit	CK_2840		0x02
	bit	DO_2840		0x01
}

register STATUS_2840 {
	address			0x0c1
	access_mode RW
	bit	EEPROM_TF	0x80
	mask	BIOS_SEL	0x60
	mask	ADSEL		0x1e
	bit	DI_2840		0x01
}

/* --------------------- AIC-7870-only definitions -------------------- */

register DSPCISTATUS {
	address			0x086
}

register BRDCTL	{
	address			0x01d
	bit	BRDDAT7		0x80
	bit	BRDDAT6		0x40
	bit	BRDDAT5		0x20
	bit	BRDSTB		0x10
	bit	BRDCS		0x08
	bit	BRDRW		0x04
	bit	BRDCTL1		0x02
	bit	BRDCTL0		0x01
}

/*
 * Serial EEPROM Control (p. 4-92 in 7870 Databook)
 * Controls the reading and writing of an external serial 1-bit
 * EEPROM Device.  In order to access the serial EEPROM, you must
 * first set the SEEMS bit that generates a request to the memory
 * port for access to the serial EEPROM device.  When the memory
 * port is not busy servicing another request, it reconfigures
 * to allow access to the serial EEPROM.  When this happens, SEERDY
 * gets set high to verify that the memory port access has been
 * granted.  
 *
 * After successful arbitration for the memory port, the SEECS bit of 
 * the SEECTL register is connected to the chip select.  The SEECK, 
 * SEEDO, and SEEDI are connected to the clock, data out, and data in 
 * lines respectively.  The SEERDY bit of SEECTL is useful in that it 
 * gives us an 800 nsec timer.  After a write to the SEECTL register, 
 * the SEERDY goes high 800 nsec later.  The one exception to this is 
 * when we first request access to the memory port.  The SEERDY goes 
 * high to signify that access has been granted and, for this case, has 
 * no implied timing.
 *
 * See 93cx6.c for detailed information on the protocol necessary to 
 * read the serial EEPROM.
 */
register SEECTL {
	address			0x01e
	bit	EXTARBACK	0x80
	bit	EXTARBREQ	0x40
	bit	SEEMS		0x20
	bit	SEERDY		0x10
	bit	SEECS		0x08
	bit	SEECK		0x04
	bit	SEEDO		0x02
	bit	SEEDI		0x01
}
/* ---------------------- Scratch RAM Offsets ------------------------- */
/* These offsets are either to values that are initialized by the board's
 * BIOS or are specified by the sequencer code.
 *
 * The host adapter card (at least the BIOS) uses 20-2f for SCSI
 * device information, 32-33 and 5a-5f as well. As it turns out, the
 * BIOS trashes 20-2f, writing the synchronous negotiation results
 * on top of the BIOS values, so we re-use those for our per-target
 * scratchspace (actually a value that can be copied directly into
 * SCSIRATE).  The kernel driver will enable synchronous negotiation
 * for all targets that have a value other than 0 in the lower four
 * bits of the target scratch space.  This should work regardless of
 * whether the bios has been installed.
 */

scratch_ram {
	address			0x020

	/*
	 * 1 byte per target starting at this address for configuration values
	 */
	TARG_SCRATCH {
		size		16
	}
	ULTRA_ENB {
		size		2
	}
	/*
	 * Bit vector of targets that have disconnection disabled.
	 */
	DISC_DSB {
		size		2
	}
	/*
	 * Length of pending message
	 */
	MSG_LEN	{
		size		1
	}
	/* We reserve 8bytes to store outgoing messages */
	MSG_OUT {
		size		8
	}
	/* Parameters for DMA Logic */
	DMAPARAMS {
		size		1
		bit	WIDEODD		0x40
		bit	SCSIEN		0x20
		bit	SDMAEN		0x10
		bit	SDMAENACK	0x10
		bit	HDMAEN		0x08
		bit	HDMAENACK	0x08
		bit	DIRECTION	0x04
		bit	FIFOFLUSH	0x02
		bit	FIFORESET	0x01
	}
	/*
	 * Number of SCBs supported by
	 * this card.
	 */
	SCBCOUNT {
		size		1
	}
	/*
	 * Two's complement of SCBCOUNT
	 */
	COMP_SCBCOUNT {
		size		1
	}
	/*
	 * Mask of bits to test against
	 * when looking at the Queue Count
	 * registers.  Works around a bug
	 * on aic7850 chips. 
	 */
	QCNTMASK {
		size		1
	}
	SEQ_FLAGS {
		size		1
		bit	RESELECTED	0x80
		bit	IDENTIFY_SEEN	0x40
		bit	TAGGED_SCB	0x20
		bit	DPHASE		0x10
		bit	PAGESCBS	0x04
		bit	WIDE_BUS	0x02
		bit	TWIN_BUS	0x01
	}
	/*
	 * Temporary storage for the
	 * target/channel/lun of a
	 * reconnecting target
	 */
	SAVED_TCL {
		size		1
	}
	SG_COUNT {
		size		1
	}
	/* working value of SG pointer */
	SG_NEXT	{
		size		4
	}
	/*
	 * head of list of SCBs awaiting
	 * selection
	 */
	WAITING_SCBH {
		size		1
	}
	SAVED_LINKPTR {
		size		1
	}
	SAVED_SCBPTR {
		size		1
	}
	/*
	 * The sequencer will stick the frist byte of any rejected message here
	 * so we can see what is getting thrown away.
	 */
	REJBYTE	{
		size		1
	}
	/*
	 * The last bus phase as seen by the sequencer. 
	 */
	LASTPHASE {
		size		1
		bit	CDI		0x80
		bit	IOI		0x40
		bit	MSGI		0x20
		mask	PHASE_MASK	CDI|IOI|MSGI
		mask	P_DATAOUT	0x00
		mask	P_DATAIN	IOI
		mask	P_COMMAND	CDI
		mask	P_MESGOUT	CDI|MSGI
		mask	P_STATUS	CDI|IOI
		mask	P_MESGIN	CDI|IOI|MSGI
		mask	P_BUSFREE	0x01
	}
	MSGIN_EXT_LEN {
		size		1
	}
	MSGIN_EXT_OPCODE {
		size		1
	}
	/*
	 * location 3, stores the last
	 * byte of an extended message if
	 * it passes the two bytes of space
	 * we allow now.  This byte isn't
	 * used for anything, it just makes
	 * the code shorter for tossing
	 * extra bytes.
	 */
	MSGIN_EXT_BYTES	{
		size		3
	}
	/*
	 * head of list of SCBs that are
	 * disconnected.  Used for SCB
	 * paging.
	 */
	DISCONNECTED_SCBH {
		size		1
	}
	/*
	 * head of list of SCBs that are
	 * not in use.  Used for SCB paging.
	 */
	FREE_SCBH {
		size		1
	}
	HSCB_ADDR {
		size		4
	}
	CUR_SCBID {
		size		1
	}
	ARG_1 {
		size		1
		mask	SEND_MSG	0x80
		mask	SEND_SENSE	0x40
		mask	SEND_REJ	0x20
		alias	RETURN_1
	}
	/*
	 * These are reserved registers in the card's scratch ram.  Some of
	 * the values are specified in the AHA2742 technical reference manual
	 * and are initialized by the BIOS at boot time.
	 */
	SCSICONF {
		address		0x05a
		size		1
		bit	RESET_SCSI	0x40
	}
	HOSTCONF {
		address		0x05d
		size		1
	}
	HA_274_BIOSCTRL	{
		address		0x05f
		size		1
		mask	BIOSMODE		0x30
		mask	BIOSDISABLED		0x30	
		bit	CHANNEL_B_PRIMARY	0x08
	}
}

const SCB_LIST_NULL	0xff


/* WDTR Message values */
const BUS_8_BIT		0x00
const BUS_16_BIT		0x01
const BUS_32_BIT		0x02
const MAX_OFFSET_8BIT		0x0f
const MAX_OFFSET_16BIT	0x08