patch-2.0.31 linux/drivers/scsi/aic7xxx.seq

Next file: linux/drivers/scsi/aic7xxx_asm.c
Previous file: linux/drivers/scsi/aic7xxx.h
Back to the patch index
Back to the overall index

diff -u --recursive --new-file v2.0.30/linux/drivers/scsi/aic7xxx.seq linux/drivers/scsi/aic7xxx.seq
@@ -1,1127 +0,0 @@
-/*+M*************************************************************************
- * Adaptec AIC7xxx device driver for Linux and FreeBSD.
- *
- * Copyright (c) 1994 John Aycock
- *   The University of Calgary Department of Computer Science.
- *
- *Modifications/enhancements:
- *  Copyright (c) 1994, 1995, 1996 Justin Gibbs. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; see the file COPYING.  If not, write to
- * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * FreeBSD, Twin, Wide, 2 command per target support, tagged queuing and other 
- * optimizations provided by Justin T. Gibbs (gibbs@FreeBSD.org)
- *
- * This version corresponds to version 1.42 of FreeBSDs aic7xxx.seq.
- *
- *-M*************************************************************************/
-
-VERSION AIC7XXX_SEQ_VER "$Id: aic7xxx.seq,v 4.0 1996/10/13 08:23:42 deang Exp $"
-
-#ifdef linux
-#include "aic7xxx_reg.h"
-#else
-#if defined(__NetBSD__)
-#include "../../../../dev/ic/aic7xxxreg.h"
-#elif defined(__FreeBSD__)
-#include "../../dev/aic7xxx/aic7xxx_reg.h"
-#endif
-#endif
-
-/*
- * We can't just use ACCUM in the sequencer code because it
- * must be treated specially by the assembler, and it currently
- * looks for the symbol 'A'.  This is the only register defined in
- * the assembler's symbol space.
- */
-A = ACCUM
-
-/* After starting the selection hardware, we check for reconnecting targets
- * as well as for our selection to complete just in case the reselection wins
- * bus arbitration.  The problem with this is that we must keep track of the
- * SCB that we've already pulled from the QINFIFO and started the selection
- * on just in case the reselection wins so that we can retry the selection at
- * a later time.  This problem cannot be resolved by holding a single entry
- * in scratch ram since a reconnecting target can request sense and this will
- * create yet another SCB waiting for selection.  The solution used here is to 
- * use byte 27 of the SCB as a pseudo-next pointer and to thread a list
- * of SCBs that are awaiting selection.  Since 0-0xfe are valid SCB offsets, 
- * SCB_LIST_NULL is 0xff which is out of range.  The kernel driver must
- * add an entry to this list every time a request sense occurs.  The sequencer
- * will automatically consume the entries.
- */
-
-/*
- * We assume that the kernel driver may reset us at any time, even in the
- * middle of a DMA, so clear DFCNTRL too.
- */
-reset:
-	clr	DFCNTRL
-	clr	SCSISIGO		/* De-assert BSY */
-/*
- * We jump to start after every bus free.
- */
-start:
-	and	FLAGS,0x0f		/* clear target specific flags */
-	mvi	SCSISEQ,ENRSELI		/* Always allow reselection */
-	clr	SCSIRATE		/*
-					 * We don't know the target we will
-					 * connect to, so default to narrow
-					 * transfers to avoid parity problems.
-					 */
-poll_for_work:
-	/*
-	 * Are we a twin channel device?
-	 * For fairness, we check the other bus first,
-	 * since we just finished a transaction on the
-	 * current channel.
-	 */
-	test	FLAGS,TWIN_BUS	jz start2
-	xor	SBLKCTL,SELBUSB			/* Toggle to the other bus */
-	test	SSTAT0,SELDI	jnz reselect
-	xor	SBLKCTL,SELBUSB			/* Toggle to the original bus */
-start2:
-	test	SSTAT0,SELDI	jnz reselect
-	cmp	WAITING_SCBH,SCB_LIST_NULL jne start_waiting
-	mov	A, QCNTMASK
-	test	QINCNT,A	jz poll_for_work
-
-/*
- * We have at least one queued SCB now and we don't have any 
- * SCBs in the list of SCBs awaiting selection.  Set the SCB
- * pointer from the FIFO so we see the right bank of SCB 
- * registers.
- */
-	mov	SCBPTR,QINFIFO
-
-/*
- * See if there is not already an active SCB for this target.  This code
- * locks out on a per target basis instead of target/lun.  Although this
- * is not ideal for devices that have multiple luns active at the same
- * time, it is faster than looping through all SCB's looking for active
- * commands.  It may be beneficial to make findscb a more general procedure
- * to see if the added cost of the search is negligible.  This code also 
- * assumes that the kernel driver will clear the active flags on board 
- * initialization, board reset, and a target SELTO.  Tagged commands
- * don't set the active bits since you can queue more than one command
- * at a time.  We do, however, look to see if there are any non-tagged
- * I/Os in progress, and requeue the command if there are.  Tagged and
- * non-tagged commands cannot be mixed to a single target.
- */
-
-test_busy:
-	mov	FUNCTION1,SCB_TCL
-	mov	A,FUNCTION1
-	test	SCB_TCL,0x88	jz test_a	/* Id < 8 && A channel */
-
-	test	ACTIVE_B,A	jnz requeue
-	test	SCB_CONTROL,TAG_ENB	jnz start_scb
-	/* Mark the current target as busy */
-	or	ACTIVE_B,A
-	jmp	start_scb
-
-/* Place the currently active SCB back on the queue for later processing */
-requeue:
-	mov	QINFIFO, SCBPTR
-	jmp	poll_for_work
-
-/*
- * Pull the first entry off of the waiting for selection list
- * We don't have to "test_busy" because only transactions that
- * have passed that test can be in the waiting_scb list.
- */
-start_waiting:
-	mov	SCBPTR,WAITING_SCBH
-	jmp	start_scb2
-
-test_a:
-	test	ACTIVE_A,A jnz requeue
-	test	SCB_CONTROL,TAG_ENB jnz start_scb
-	/* Mark the current target as busy */
-	or	ACTIVE_A,A
-
-start_scb:
-	mov	SCB_NEXT,WAITING_SCBH
-	mov	WAITING_SCBH, SCBPTR
-start_scb2:
-	and	SINDEX,0xf7,SBLKCTL	/* Clear the channel select bit */
-	and	A,0x08,SCB_TCL		/* Get new channel bit */
-	or	SINDEX,A
-	mov	SBLKCTL,SINDEX		/* select channel */
-	mov	SCB_TCL	call initialize_scsiid
-
-/*
- * Enable selection phase as an initiator, and do automatic ATN
- * after the selection.  We do this now so that we can overlap the
- * rest of our work to set up this target with the arbitration and
- * selection bus phases.
- */
-start_selection:
-	mvi	SCSISEQ,0x58		/* ENSELO|ENAUTOATNO|ENRSELI */
-
-/*
- * As soon as we get a successful selection, the target should go
- * into the message out phase since we have ATN asserted.  Prepare
- * the message to send.
- *
- * Messages are stored in scratch RAM starting with a length byte
- * followed by the message itself.
- */
-	test	SCB_CMDLEN,0xff jnz mk_identify	/* 0 Length Command? */
-
-/*
- * The kernel has sent us an SCB with no command attached.  This implies
- * that the kernel wants to send a message of some sort to this target,
- * so we interrupt the driver, allow it to fill the message buffer, and
- * then go back into the arbitration loop
- */
-	mvi     INTSTAT,AWAITING_MSG
-	jmp     wait_for_selection
-
-mk_identify:
-	and	A,DISCENB,SCB_CONTROL	/* mask off disconnect privledge */
-
-	and	MSG0,0x7,SCB_TCL	/* lun */
-	or	MSG0,A			/* or in disconnect privledge */
-	or	MSG0,MSG_IDENTIFY
-	mvi	MSG_LEN, 1
-
-	test	SCB_CONTROL,0xb0 jz  !message	/* WDTR, SDTR or TAG?? */
-/*
- * Send a tag message if TAG_ENB is set in the SCB control block.
- * Use SCB_TAG (the position in the kernel's SCB array) as the tag value.
- */
-
-mk_tag:
-	mvi	DINDEX, MSG1
-	test	SCB_CONTROL,TAG_ENB jz mk_tag_done
-	and	DINDIR,0x23,SCB_CONTROL
-	mov	DINDIR,SCB_TAG
-
-	add	MSG_LEN,COMP_MSG0,DINDEX	/* update message length */
-
-mk_tag_done:
-
-	test	SCB_CONTROL,0x90 jz !message	/* NEEDWDTR|NEEDSDTR */
-	mov	DINDEX	call mk_dtr	/* build DTR message if needed */
-
-!message:
-wait_for_selection:
-	test	SSTAT0,SELDO	jnz select 
-	test	SSTAT0,SELDI	jz wait_for_selection
-
-/*
- * Reselection has been initiated by a target. Make a note that we've been
- * reselected, but haven't seen an IDENTIFY message from the target
- * yet.
- */
-reselect:
-	clr	MSG_LEN		/* Don't have anything in the mesg buffer */
-	mov	SELID		call initialize_scsiid
-	or	FLAGS,RESELECTED
-	jmp	select2
-
-/*
- * After the selection, remove this SCB from the "waiting for selection"
- * list.  This is achieved by simply moving our "next" pointer into
- * WAITING_SCBH.  Our next pointer will be set to null the next time this
- * SCB is used, so don't bother with it now.
- */
-select:
-	mov	WAITING_SCBH,SCB_NEXT
-	or	FLAGS,SELECTED
-select2:
-/*
- * Set CLRCHN here before the target has entered a data transfer mode -
- * with synchronous SCSI, if you do it later, you blow away some
- * data in the SCSI FIFO that the target has already sent to you.
- */
-	or	SXFRCTL0,CLRCHN
-/*
- * Initialize SCSIRATE with the appropriate value for this target.
- */
-	call	ndx_dtr
-	mov	SCSIRATE,SINDIR
-
-/*
- * Initialize Ultra mode setting.
- */
-	mov	FUNCTION1,SCSIID
-	mov	A,FUNCTION1
-	and	SINDEX,0xdf,SXFRCTL0		/* default to Ultra disabled */
-	test	SCSIID, 0x80	 jnz ultra_b	/* Target ID > 7 */
-	test	SBLKCTL, SELBUSB jnz ultra_b	/* Second channel device */
-	test	ULTRA_ENB,A	 jz  set_sxfrctl0
-	or	SINDEX, ULTRAEN  jmp set_sxfrctl0
-ultra_b:
-	test	ULTRA_ENB_B,A	 jz  set_sxfrctl0
-	or	SINDEX, ULTRAEN
-
-set_sxfrctl0:
-	mov	SXFRCTL0,SINDEX
-
-	mvi	SCSISEQ,ENAUTOATNP		/*
-						 * ATN on parity errors
-						 * for "in" phases
-						 */
-	mvi	CLRSINT1,CLRBUSFREE
-	mvi	CLRSINT0,0x60			/* CLRSELDI|CLRSELDO */
-/*
- * Main loop for information transfer phases.  If BSY is false, then
- * we have a bus free condition, expected or not.  Otherwise, wait
- * for the target to assert REQ before checking MSG, C/D and I/O
- * for the bus phase.
- *
- */
-ITloop:
-	test	SSTAT1,BUSFREE	jnz p_busfree
-	test	SSTAT1,REQINIT	jz ITloop
-
-	and	A,PHASE_MASK,SCSISIGI
-	mov	LASTPHASE,A
-	mov	SCSISIGO,A
-
-	cmp	ALLZEROS,A	je p_dataout
-	cmp	A,P_DATAIN	je p_datain
-	cmp	A,P_COMMAND	je p_command
-	cmp	A,P_MESGOUT	je p_mesgout
-	cmp	A,P_STATUS	je p_status
-	cmp	A,P_MESGIN	je p_mesgin
-
-	mvi	INTSTAT,BAD_PHASE	/* unknown phase - signal driver */
-	jmp	ITloop			/* Try reading the bus again. */
-
-p_dataout:
-	mvi	DMAPARAMS,0x7d			/*
-						 * WIDEODD|SCSIEN|SDMAEN|HDMAEN|
-						 * DIRECTION|FIFORESET
-						 */
-	jmp	data_phase_init
-
-/*
- * If we re-enter the data phase after going through another phase, the
- * STCNT may have been cleared, so restore it from the residual field.
- */
-data_phase_reinit:
-	mov	STCNT0,SCB_RESID_DCNT0
-	mov	STCNT1,SCB_RESID_DCNT1
-	mov	STCNT2,SCB_RESID_DCNT2
-	jmp	data_phase_loop
-
-p_datain:
-	mvi	DMAPARAMS,0x79		/*
-					 * WIDEODD|SCSIEN|SDMAEN|HDMAEN|
-					 * !DIRECTION|FIFORESET
-					 */
-data_phase_init:
-	call	assert
-
-	test	FLAGS, DPHASE	jnz data_phase_reinit
-	call	sg_scb2ram
-	or	FLAGS, DPHASE		/* We have seen a data phase */
-
-data_phase_loop:
-/* Guard against overruns */
-	test	SG_COUNT, 0xff jnz data_phase_inbounds
-/*
- * Turn on 'Bit Bucket' mode, set the transfer count to
- * 16meg and let the target run until it changes phase.
- * When the transfer completes, notify the host that we
- * had an overrun.
- */
-	or	SXFRCTL1,BITBUCKET
-	mvi	STCNT0,0xff
-	mvi	STCNT1,0xff
-	mvi	STCNT2,0xff
-
-data_phase_inbounds:
-/* If we are the last SG block, don't set wideodd. */
-	cmp	SG_COUNT,0x01 jne data_phase_wideodd
-	and	DMAPARAMS, 0xbf		/* Turn off WIDEODD */
-data_phase_wideodd:
-	mov	DMAPARAMS  call dma
-
-/* Go tell the host about any overruns */
-	test	SXFRCTL1,BITBUCKET jnz data_phase_overrun
-
-/* Exit if we had an underrun */
-	test	SSTAT0,SDONE	jz data_phase_finish /* underrun STCNT != 0 */
-
-/*
- * Advance the scatter-gather pointers if needed 
- */
-sg_advance:
-	dec	SG_COUNT	/* one less segment to go */
-
-	test	SG_COUNT, 0xff	jz data_phase_finish /* Are we done? */
-
-	clr	A			/* add sizeof(struct scatter) */
-	add	SG_NEXT0,SG_SIZEOF,SG_NEXT0
-	adc	SG_NEXT1,A,SG_NEXT1
-
-/*
- * Load a struct scatter and set up the data address and length.
- * If the working value of the SG count is nonzero, then
- * we need to load a new set of values.
- *
- * This, like all DMA's, assumes a little-endian host data storage.
- */
-sg_load:
-	clr	HCNT2
-	clr	HCNT1
-	mvi	HCNT0,SG_SIZEOF
-
-	mov	HADDR0,SG_NEXT0
-	mov	HADDR1,SG_NEXT1
-	mov	HADDR2,SG_NEXT2
-	mov	HADDR3,SG_NEXT3
-
-	or	DFCNTRL,0xd			/* HDMAEN|DIRECTION|FIFORESET */
-
-/*
- * Wait for DMA from host memory to data FIFO to complete, then disable
- * DMA and wait for it to acknowledge that it's off.
- */
-dma_finish:
-	test	DFSTATUS,HDONE	jz dma_finish
-	/* Turn off DMA preserving WIDEODD */
-	and	DFCNTRL,WIDEODD
-dma_finish2:
-	test	DFCNTRL,HDMAENACK jnz dma_finish2
-
-/*
- * Copy data from FIFO into SCB data pointer and data count.  In
- * both FreeBSD and Linux, the scatter list entry is 8 bytes.
- * 
- * struct ahc_dma_seg {
- *       physaddr addr;                  four bytes, little-endian order
- *       long    len;                    four bytes, little endian order
- * };
- */
-
-	mov	HADDR0,DFDAT
-	mov	HADDR1,DFDAT
-	mov	HADDR2,DFDAT
-	mov	HADDR3,DFDAT
-	mov	HCNT0,DFDAT
-	mov	HCNT1,DFDAT
-	mov	HCNT2,DFDAT
-
-/* Load STCNT as well.  It is a mirror of HCNT */
-	mov	STCNT0,HCNT0
-	mov	STCNT1,HCNT1
-	mov	STCNT2,HCNT2
-        test    SSTAT1,PHASEMIS  jz data_phase_loop
-
-data_phase_finish:
-/*
- * After a DMA finishes, save the SG and STCNT residuals back into the SCB
- * We use STCNT instead of HCNT, since it's a reflection of how many bytes 
- * were transferred on the SCSI (as opposed to the host) bus.
- */
-	mov	SCB_RESID_DCNT0,STCNT0
-	mov	SCB_RESID_DCNT1,STCNT1
-	mov	SCB_RESID_DCNT2,STCNT2
-	mov	SCB_RESID_SGCNT, SG_COUNT
-	jmp	ITloop
-
-data_phase_overrun:
-/*
- * Turn off BITBUCKET mode and notify the host
- */
-	and	SXFRCTL1,0x7f		/* ~BITBUCKET */
-	mvi	INTSTAT,DATA_OVERRUN
-	jmp	ITloop
-
-/*
- * Command phase.  Set up the DMA registers and let 'er rip.
- */
-p_command:
-	call	assert
-
-/*
- * Load HADDR and HCNT.
- */
-	mov	HADDR0, SCB_CMDPTR0
-	mov	HADDR1, SCB_CMDPTR1
-	mov	HADDR2, SCB_CMDPTR2
-	mov	HADDR3, SCB_CMDPTR3
-	mov	HCNT0, SCB_CMDLEN
-	clr	HCNT1
-	clr	HCNT2
-
-	mov	STCNT0, HCNT0
-	mov	STCNT1, HCNT1
-	mov	STCNT2, HCNT2
-
-	mvi	0x3d		call dma	# SCSIEN|SDMAEN|HDMAEN|
-						#   DIRECTION|FIFORESET
-	jmp	ITloop
-
-/*
- * Status phase.  Wait for the data byte to appear, then read it
- * and store it into the SCB.
- */
-p_status:
-	mvi	SCB_TARGET_STATUS	call inb_first
-	jmp	mesgin_done
-
-/*
- * Message out phase.  If there is not an active message, but the target
- * took us into this phase anyway, build a no-op message and send it.
- */
-p_mesgout:
-	test	MSG_LEN, 0xff	jnz  p_mesgout_start
-	mvi	MSG_NOP		call mk_mesg	/* build NOP message */
-
-p_mesgout_start:
-/*
- * Set up automatic PIO transfer from MSG0.  Bit 3 in
- * SXFRCTL0 (SPIOEN) is already on.
- */
-	mvi	SINDEX,MSG0
-	mov	DINDEX,MSG_LEN
-
-/*
- * When target asks for a byte, drop ATN if it's the last one in
- * the message.  Otherwise, keep going until the message is exhausted.
- *
- * Keep an eye out for a phase change, in case the target issues
- * a MESSAGE REJECT.
- */
-p_mesgout_loop:
-	test	SSTAT1,PHASEMIS	jnz p_mesgout_phasemis
-	test	SSTAT0,SPIORDY	jz p_mesgout_loop
-	test	SSTAT1,PHASEMIS	jnz p_mesgout_phasemis
-	cmp	DINDEX,1	jne p_mesgout_outb	/* last byte? */
-	mvi	CLRSINT1,CLRATNO			/* drop ATN */
-p_mesgout_outb:
-	dec	DINDEX
-	or	CLRSINT0, CLRSPIORDY
-	mov	SCSIDATL,SINDIR
-	
-p_mesgout4:
-	test	DINDEX,0xff	jnz p_mesgout_loop
-
-/*
- * If the next bus phase after ATN drops is a message out, it means
- * that the target is requesting that the last message(s) be resent.
- */
-p_mesgout_snoop:
-	test	SSTAT1,BUSFREE	jnz p_mesgout_done
-	test	SSTAT1,REQINIT	jz p_mesgout_snoop
-
-	test	SSTAT1,PHASEMIS	jnz p_mesgout_done
-
-	or	SCSISIGO,ATNO			/* turn on ATNO */
-
-	jmp	ITloop
-
-p_mesgout_phasemis:
-	mvi	CLRSINT1,CLRATNO	/* Be sure to turn ATNO off */
-p_mesgout_done:
-	clr	MSG_LEN			/* no active msg */
-	jmp	ITloop
-
-/*
- * Message in phase.  Bytes are read using Automatic PIO mode.
- */
-p_mesgin:
-	mvi	A		call inb_first	/* read the 1st message byte */
-	mov	REJBYTE,A			/* save it for the driver */
-
-	test	A,MSG_IDENTIFY		jnz mesgin_identify
-	cmp	A,MSG_DISCONNECT	je mesgin_disconnect
-	cmp	A,MSG_SDPTRS		je mesgin_sdptrs
-	cmp	ALLZEROS,A		je mesgin_complete
-	cmp	A,MSG_RDPTRS		je mesgin_rdptrs
-	cmp	A,MSG_EXTENDED		je mesgin_extended
-	cmp	A,MSG_REJECT		je mesgin_reject
-
-rej_mesgin:
-/*
- * We have no idea what this message in is, and there's no way
- * to pass it up to the kernel, so we issue a message reject and
- * hope for the best.  Since we're now using manual PIO mode to
- * read in the message, there should no longer be a race condition
- * present when we assert ATN.  In any case, rejection should be a
- * rare occurrence - signal the driver when it happens.
- */
-	or	SCSISIGO,ATNO			/* turn on ATNO */
-	mvi	INTSTAT,SEND_REJECT		/* let driver know */
-
-	mvi	MSG_REJECT	call mk_mesg
-
-mesgin_done:
-	call	inb_last			/*ack & turn auto PIO back on*/
-	jmp	ITloop
-
-
-mesgin_complete:
-/*
- * We got a "command complete" message, so put the SCB_TAG into QUEUEOUT,
- * and trigger a completion interrupt.  Check status for non zero return
- * and interrupt driver if needed.  This allows the driver to interpret
- * errors only when they occur instead of always uploading the scb.  If
- * the status is SCSI_CHECK, the driver will download a new scb requesting
- * sense to replace the old one, modify the "waiting for selection" SCB list
- * and set RETURN_1 to SEND_SENSE.  If RETURN_1 is set to SEND_SENSE the
- * sequencer imediately jumps to main loop where it will run down the waiting
- * SCB list and process the sense request.  If the kernel driver does not
- * wish to request sense, it need only clear RETURN_1, and the command is
- * allowed to complete.  We don't bother to post to the QOUTFIFO in the
- * error case since it would require extra work in the kernel driver to
- * ensure that the entry was removed before the command complete code tried
- * processing it.
- *
- * First check for residuals
- */
-	test	SCB_RESID_SGCNT,0xff	jz check_status
-/*
- * If we have a residual count, interrupt and tell the host.  Other
- * alternatives are to pause the sequencer on all command completes (yuck),
- * dma the resid directly to the host (slick, we may have space to do it now)
- * or have the sequencer pause itself when it encounters a non-zero resid 
- * (unnecessary pause just to flag the command -yuck-, but takes one instruction
- * and since it shouldn't happen that often is good enough for our purposes).  
- */
-resid:
-	mvi	INTSTAT,RESIDUAL
-
-check_status:
-	test	SCB_TARGET_STATUS,0xff	jz status_ok	/* Good Status? */
-	mvi	INTSTAT,BAD_STATUS			/* let driver know */
-	cmp	RETURN_1, SEND_SENSE	jne status_ok
-	jmp	mesgin_done
-
-status_ok:
-/* First, mark this target as free. */
-	test	SCB_CONTROL,TAG_ENB jnz test_immediate	/*
-							 * Tagged commands
-							 * don't busy the
-							 * target.
-							 */
-	mov	FUNCTION1,SCB_TCL
-	mov	A,FUNCTION1
-	test	SCB_TCL,0x88 jz clear_a
-	xor	ACTIVE_B,A
-	jmp	test_immediate
-
-clear_a:
-	xor	ACTIVE_A,A
-
-test_immediate:
-	test    SCB_CMDLEN,0xff jnz complete  /* Immediate message complete */
-/*
- * Pause the sequencer until the driver gets around to handling the command
- * complete.  This is so that any action that might require careful timing
- * with the completion of this command can occur.
- */
-	mvi	INTSTAT,IMMEDDONE
-	jmp	start
-complete:
-	mov	QOUTFIFO,SCB_TAG
-	mvi	INTSTAT,CMDCMPLT
-	jmp	mesgin_done
-
-
-/*
- * Is it an extended message?  We only support the synchronous and wide data
- * transfer request messages, which will probably be in response to
- * WDTR or SDTR message outs from us.  If it's not SDTR or WDTR, reject it -
- * apparently this can be done after any message in byte, according
- * to the SCSI-2 spec.
- */
-mesgin_extended:
-	mvi	ARG_1		call inb_next	/* extended message length */
-	mvi	REJBYTE_EXT	call inb_next	/* extended message code */
-
-	cmp	REJBYTE_EXT,MSG_SDTR	je p_mesginSDTR
-	cmp	REJBYTE_EXT,MSG_WDTR	je p_mesginWDTR
-	jmp	rej_mesgin
-
-p_mesginWDTR:
-	cmp	ARG_1,2		jne rej_mesgin	/* extended mesg length=2 */
-	mvi	ARG_1		call inb_next	/* Width of bus */
-	mvi	INTSTAT,WDTR_MSG		/* let driver know */
-	test	RETURN_1,0xff jz mesgin_done	/* Do we need to send WDTR? */
-	cmp	RETURN_1,SEND_REJ je rej_mesgin /*
-						 * Bus width was too large 
-						 * Reject it.
-						 */
-
-/* We didn't initiate the wide negotiation, so we must respond to the request */
-	and	RETURN_1,0x7f			/* Clear the SEND_WDTR Flag */
-	mvi	DINDEX,MSG0
-	mvi	MSG0	call mk_wdtr		/* build WDTR message */
-	or	SCSISIGO,ATNO			/* turn on ATNO */
-	jmp	mesgin_done
-
-p_mesginSDTR:
-	cmp	ARG_1,3		jne rej_mesgin	/* extended mesg length=3 */
-	mvi	ARG_1		call inb_next	/* xfer period */
-	mvi	A		call inb_next	/* REQ/ACK offset */
-	mvi	INTSTAT,SDTR_MSG		/* call driver to convert */
-
-	test	RETURN_1,0xff	jz mesgin_done  /* Do we need to mk_sdtr/rej */
-	cmp	RETURN_1,SEND_REJ je rej_mesgin /*
-						 * Requested SDTR too small
-						 * Reject it.
-						 */
-	clr	ARG_1				/* Use the scratch ram rate */
-	mvi	DINDEX, MSG0
-	mvi     MSG0     call mk_sdtr
-	or	SCSISIGO,ATNO			/* turn on ATNO */
-	jmp	mesgin_done
-
-/*
- * Is it a disconnect message?  Set a flag in the SCB to remind us
- * and await the bus going free.
- */
-mesgin_disconnect:
-	or	SCB_CONTROL,DISCONNECTED
-	test	FLAGS, PAGESCBS jz mesgin_done
-/*
- * Link this SCB into the DISCONNECTED list.  This list holds the
- * candidates for paging out an SCB if one is needed for a new command.
- * Modifying the disconnected list is a critical(pause dissabled) section.
- */
-	mvi	SCB_PREV, SCB_LIST_NULL
-	mvi	SEQCTL,0x50			/* PAUSEDIS|FASTMODE */
-	mov	SCB_NEXT, DISCONNECTED_SCBH
-	mov	DISCONNECTED_SCBH, SCBPTR
-	cmp	SCB_NEXT,SCB_LIST_NULL je linkdone
-	mov	SCBPTR,SCB_NEXT
-	mov	SCB_PREV,DISCONNECTED_SCBH
-	mov	SCBPTR,DISCONNECTED_SCBH
-linkdone:
-	mvi	SEQCTL,0x10			/* !PAUSEDIS|FASTMODE */
-	jmp	mesgin_done
-
-/*
- * Save data pointers message?  Copy working values into the SCB,
- * usually in preparation for a disconnect.
- */
-mesgin_sdptrs:
-	call	sg_ram2scb
-	jmp	mesgin_done
-
-/*
- * Restore pointers message?  Data pointers are recopied from the
- * SCB anytime we enter a data phase for the first time, so all
- * we need to do is clear the DPHASE flag and let the data phase
- * code do the rest.
- */
-mesgin_rdptrs:
-	and	FLAGS,0xef			/*
-						 * !DPHASE we'll reload them
-						 * the next time through
-						 */
-	jmp	mesgin_done
-
-/*
- * Identify message?  For a reconnecting target, this tells us the lun
- * that the reconnection is for - find the correct SCB and switch to it,
- * clearing the "disconnected" bit so we don't "find" it by accident later.
- */
-mesgin_identify:
-	test	A,0x78	jnz rej_mesgin	/*!DiscPriv|!LUNTAR|!Reserved*/
-
-	and	A,0x07			/* lun in lower three bits */
-	or      SAVED_TCL,A,SELID          
-	and     SAVED_TCL,0xf7
-	and     A,SELBUSB,SBLKCTL	/* B Channel?? */
-	or      SAVED_TCL,A
-	call	inb_last		/* ACK */
-
-/*
- * Here we "snoop" the bus looking for a SIMPLE QUEUE TAG message.
- * If we get one, we use the tag returned to switch to find the proper
- * SCB.  With SCB paging, this requires using findSCB for both tagged
- * and non-tagged transactions since the SCB may exist in any slot.
- * If we're not using SCB paging, we can use the tag as the direct
- * index to the SCB.
- */
-	mvi	ARG_1,SCB_LIST_NULL	/* Default to no-tag */
-snoop_tag_loop:
-	test	SSTAT1,BUSFREE	jnz use_findSCB
-	test	SSTAT1,REQINIT	jz snoop_tag_loop
-	test	SSTAT1,PHASEMIS	jnz use_findSCB
-	mvi	A		call inb_first
-	cmp	A,MSG_SIMPLE_TAG jne use_findSCB
-get_tag:
-	mvi	ARG_1	call inb_next	/* tag value */
-/*
- * See if the tag is in range.  The tag is < SCBCOUNT if we add
- * the complement of SCBCOUNT to the incoming tag and there is
- * no carry.
- */
-	mov	A,COMP_SCBCOUNT	
-	add	SINDEX,A,ARG_1
-	jc	abort_tag
-
-/*
- * Ensure that the SCB the tag points to is for a SCB transaction
- * to the reconnecting target.
- */
-	test	FLAGS, PAGESCBS	jz index_by_tag
-	call	inb_last			/* Ack Tag */
-use_findSCB:
-	mov	ALLZEROS	call findSCB	  /* Have to search */
-setup_SCB:
-	and	SCB_CONTROL,0xfb	  /* clear disconnect bit in SCB */
-	or	FLAGS,IDENTIFY_SEEN	  /* make note of IDENTIFY */
-	jmp	ITloop
-index_by_tag:
-	mov	SCBPTR,ARG_1
-	mov	A,SAVED_TCL
-	cmp	SCB_TCL,A		jne abort_tag
-	test	SCB_CONTROL,TAG_ENB	jz  abort_tag
-	call	inb_last			/* Ack Successful tag */
-	jmp	setup_SCB
-
-abort_tag:
-	or	SCSISIGO,ATNO			/* turn on ATNO */
-	mvi	INTSTAT,ABORT_TAG 		/* let driver know */
-	mvi	MSG_ABORT_TAG	call mk_mesg	/* ABORT TAG message */
-	jmp	mesgin_done
-
-/*
- * Message reject?  Let the kernel driver handle this.  If we have an 
- * outstanding WDTR or SDTR negotiation, assume that it's a response from 
- * the target selecting 8bit or asynchronous transfer, otherwise just ignore 
- * it since we have no clue what it pertains to.
- */
-mesgin_reject:
-	mvi	INTSTAT, REJECT_MSG
-	jmp	mesgin_done
-
-/*
- * [ ADD MORE MESSAGE HANDLING HERE ]
- */
-
-/*
- * Bus free phase.  It might be useful to interrupt the device
- * driver if we aren't expecting this.  For now, make sure that
- * ATN isn't being asserted and look for a new command.
- */
-p_busfree:
-	mvi	CLRSINT1,CLRATNO
-	clr	LASTPHASE
-
-/*
- * if this is an immediate command, perform a pseudo command complete to
- * notify the driver.
- */
-	test	SCB_CMDLEN,0xff	jz status_ok
-	jmp	start
-
-/*
- * Locking the driver out, build a one-byte message passed in SINDEX
- * if there is no active message already.  SINDEX is returned intact.
- */
-mk_mesg:
-	mvi	SEQCTL,0x50			/* PAUSEDIS|FASTMODE */
-	test	MSG_LEN,0xff	jz mk_mesg1	/* Should always succeed */
-	
-	/*
-	 * Hmmm.  For some reason the mesg buffer is in use.
-	 * Tell the driver.  It should look at SINDEX to find
-	 * out what we wanted to use the buffer for and resolve
-	 * the conflict.
-	 */
-	mvi	SEQCTL,0x10			/* !PAUSEDIS|FASTMODE */
-	mvi	INTSTAT,MSG_BUFFER_BUSY
-
-mk_mesg1:
-	mvi	MSG_LEN,1		/* length = 1 */
-	mov	MSG0,SINDEX		/* 1-byte message */
-	mvi	SEQCTL,0x10	ret	/* !PAUSEDIS|FASTMODE */
-
-/*
- * Functions to read data in Automatic PIO mode.
- *
- * According to Adaptec's documentation, an ACK is not sent on input from
- * the target until SCSIDATL is read from.  So we wait until SCSIDATL is
- * latched (the usual way), then read the data byte directly off the bus
- * using SCSIBUSL.  When we have pulled the ATN line, or we just want to
- * acknowledge the byte, then we do a dummy read from SCISDATL.  The SCSI
- * spec guarantees that the target will hold the data byte on the bus until
- * we send our ACK.
- *
- * The assumption here is that these are called in a particular sequence,
- * and that REQ is already set when inb_first is called.  inb_{first,next}
- * use the same calling convention as inb.
- */
-
-inb_next:
-	or	CLRSINT0, CLRSPIORDY
-	mov	NONE,SCSIDATL			/*dummy read from latch to ACK*/
-inb_next_wait:
-	test	SSTAT1,PHASEMIS	jnz mesgin_phasemis
-	test	SSTAT0,SPIORDY	jz inb_next_wait /* wait for next byte */
-inb_first:
-	mov	DINDEX,SINDEX
-	test	SSTAT1,PHASEMIS	jnz mesgin_phasemis
-	mov	DINDIR,SCSIBUSL	ret		/*read byte directly from bus*/
-inb_last:
-	mov	NONE,SCSIDATL ret		/*dummy read from latch to ACK*/
-
-mesgin_phasemis:
-/*
- * We expected to receive another byte, but the target changed phase
- */
-	mvi	INTSTAT, MSGIN_PHASEMIS
-	jmp	ITloop
-
-/*
- * DMA data transfer.  HADDR and HCNT must be loaded first, and
- * SINDEX should contain the value to load DFCNTRL with - 0x3d for
- * host->scsi, or 0x39 for scsi->host.  The SCSI channel is cleared
- * during initialization.
- */
-dma:
-	mov	DFCNTRL,SINDEX
-dma1:
-	test	SSTAT0,DMADONE	jnz dma3
-	test	SSTAT1,PHASEMIS	jz dma1		/* ie. underrun */
-
-/*
- * We will be "done" DMAing when the transfer count goes to zero, or
- * the target changes the phase (in light of this, it makes sense that
- * the DMA circuitry doesn't ACK when PHASEMIS is active).  If we are
- * doing a SCSI->Host transfer, the data FIFO should be flushed auto-
- * magically on STCNT=0 or a phase change, so just wait for FIFO empty
- * status.
- */
-dma3:
-	test	SINDEX,DIRECTION	jnz dma5
-dma4:
-	test	DFSTATUS,FIFOEMP	jz dma4
-
-/*
- * Now shut the DMA enables off and make sure that the DMA enables are 
- * actually off first lest we get an ILLSADDR.
- */
-dma5:
-	/* disable DMA, but maintain WIDEODD */
-	and	DFCNTRL,WIDEODD
-dma6:
-	test	DFCNTRL,0x38	jnz dma6  /* SCSIENACK|SDMAENACK|HDMAENACK */
-
-	ret
-
-/*
- * Common SCSI initialization for selection and reselection.  Expects
- * the target SCSI ID to be in the upper four bits of SINDEX, and A's
- * contents are stomped on return.
- */
-initialize_scsiid:
-	and	SINDEX,0xf0		/* Get target ID */
-	and	A,0x0f,SCSIID
-	or	SINDEX,A
-	mov	SCSIID,SINDEX ret
-
-/*
- * Assert that if we've been reselected, then we've seen an IDENTIFY
- * message.
- */
-assert:
-	test	FLAGS,RESELECTED	jz return	/* reselected? */
-	test	FLAGS,IDENTIFY_SEEN	jnz return	/* seen IDENTIFY? */
-
-	mvi	INTSTAT,NO_IDENT 	ret	/* no - cause a kernel panic */
-
-/*
- * Locate the SCB matching the target ID/channel/lun in SAVED_TCL, and the tag
- * value in ARG_1.  If ARG_1 == SCB_LIST_NULL, we're looking for a non-tagged
- * SCB.  Have the kernel print a warning message if it can't be found, and
- * generate an ABORT/ABORT_TAG message to the target.  SINDEX should be
- * cleared on call.
- */
-findSCB:
-	mov	A,SAVED_TCL
-	mov	SCBPTR,SINDEX			/* switch to next SCB */
-	mvi	SEQCTL,0x50			/* PAUSEDIS|FASTMODE */
-	cmp	SCB_TCL,A	jne findSCB1 /* target ID/channel/lun match? */
-	test	SCB_CONTROL,DISCONNECTED jz findSCB1 /*should be disconnected*/
-	test	SCB_CONTROL,TAG_ENB jnz findTaggedSCB
-	cmp	ARG_1,SCB_LIST_NULL je foundSCB
-	jmp	findSCB1
-findTaggedSCB:
-	mov	A, ARG_1			/* Tag passed in ARG_1 */
-	cmp	SCB_TAG,A	jne findSCB1	/* Found it? */
-foundSCB:
-	test	FLAGS,PAGESCBS	jz foundSCB_ret
-/* Remove this SCB from the disconnection list */
-	cmp	SCB_NEXT,SCB_LIST_NULL je unlink_prev
-	mov	SAVED_LINKPTR, SCB_PREV
-	mov	SCBPTR, SCB_NEXT
-	mov	SCB_PREV, SAVED_LINKPTR
-	mov	SCBPTR, SINDEX
-unlink_prev:
-	cmp	SCB_PREV,SCB_LIST_NULL	je rHead/* At the head of the list */
-	mov	SAVED_LINKPTR, SCB_NEXT
-	mov	SCBPTR, SCB_PREV
-	mov	SCB_NEXT, SAVED_LINKPTR
-	mov	SCBPTR, SINDEX
-	mvi	SEQCTL,0x10	ret		/* !PAUSEDIS|FASTMODE */
-rHead:
-	mov	DISCONNECTED_SCBH,SCB_NEXT
-foundSCB_ret:
-	mvi	SEQCTL,0x10	ret		/* !PAUSEDIS|FASTMODE */
-
-findSCB1:
-	mvi	SEQCTL,0x10			/* !PAUSEDIS|FASTMODE */
-	inc	SINDEX
-	mov	A,SCBCOUNT
-	cmp	SINDEX,A	jne findSCB
-
-	mvi	INTSTAT,NO_MATCH		/* not found - signal kernel */
-	cmp	RETURN_1,SCB_PAGEDIN je return
-	or	SCSISIGO,ATNO			/* assert ATNO */
-	cmp	ARG_1,SCB_LIST_NULL jne find_abort_tag
-	mvi	MSG_ABORT	call mk_mesg
-	jmp	ITloop
-find_abort_tag:
-	mvi	MSG_ABORT_TAG	call mk_mesg
-	jmp	ITloop
-
-/*
- * Make a working copy of the scatter-gather parameters from the SCB.
- */
-sg_scb2ram:
-	mov	HADDR0, SCB_DATAPTR0
-	mov	HADDR1, SCB_DATAPTR1
-	mov	HADDR2, SCB_DATAPTR2
-	mov	HADDR3, SCB_DATAPTR3
-	mov	HCNT0, SCB_DATACNT0
-	mov	HCNT1, SCB_DATACNT1
-	mov	HCNT2, SCB_DATACNT2
-
-	mov	STCNT0, HCNT0
-	mov	STCNT1, HCNT1
-	mov	STCNT2, HCNT2
-
-	mov	SG_COUNT,SCB_SGCOUNT
-
-	mov	SG_NEXT0, SCB_SGPTR0
-	mov	SG_NEXT1, SCB_SGPTR1
-	mov	SG_NEXT2, SCB_SGPTR2
-	mov	SG_NEXT3, SCB_SGPTR3 ret
-
-/*
- * Copying RAM values back to SCB, for Save Data Pointers message, but
- * only if we've actually been into a data phase to change them.  This
- * protects against bogus data in scratch ram and the residual counts
- * since they are only initialized when we go into data_in or data_out.
- */
-sg_ram2scb:
-	test	FLAGS, DPHASE	jz return
-	mov	SCB_SGCOUNT,SG_COUNT
-
-	mov	SCB_SGPTR0,SG_NEXT0
-	mov	SCB_SGPTR1,SG_NEXT1
-	mov	SCB_SGPTR2,SG_NEXT2
-	mov	SCB_SGPTR3,SG_NEXT3
-	
-	mov	SCB_DATAPTR0,SHADDR0
-	mov	SCB_DATAPTR1,SHADDR1
-	mov	SCB_DATAPTR2,SHADDR2
-	mov	SCB_DATAPTR3,SHADDR3
-
-/*
- * Use the residual number since STCNT is corrupted by any message transfer
- */
-	mov	SCB_DATACNT0,SCB_RESID_DCNT0
-	mov	SCB_DATACNT1,SCB_RESID_DCNT1
-	mov	SCB_DATACNT2,SCB_RESID_DCNT2 ret
-
-/*
- * Add the array base TARG_SCRATCH to the target offset (the target address
- * is in SCSIID), and return the result in SINDEX.  The accumulator
- * contains the 3->8 decoding of the target ID on return.
- */
-ndx_dtr:
-	shr	A,SCSIID,4
-	test	SBLKCTL,SELBUSB	jz ndx_dtr_2
-	or	A,0x08		/* Channel B entries add 8 */
-ndx_dtr_2:
-	add	SINDEX,TARG_SCRATCH,A ret
-
-/*
- * If we need to negotiate transfer parameters, build the WDTR or SDTR message
- * starting at the address passed in SINDEX.  DINDEX is modified on return.
- * The SCSI-II spec requires that Wide negotiation occur first and you can
- * only negotiate one or the other at a time otherwise in the event of a message
- * reject, you wouldn't be able to tell which message was the culprit.
- */
-mk_dtr:
-	test	SCB_CONTROL,NEEDWDTR jnz  mk_wdtr_16bit
-	mvi	ARG_1, MAXOFFSET	/* Force an offset of 15 or 8 if WIDE */
-
-mk_sdtr:
-	mvi	DINDIR,1		/* extended message */
-	mvi	DINDIR,3		/* extended message length = 3 */
-	mvi	DINDIR,1		/* SDTR code */
-	call	sdtr_to_rate
-	mov	DINDIR,RETURN_1		/* REQ/ACK transfer period */
-	cmp	ARG_1, MAXOFFSET je mk_sdtr_max_offset
-	and	DINDIR,0x0f,SINDIR	/* Sync Offset */
-
-mk_sdtr_done:
-	add	MSG_LEN,COMP_MSG0,DINDEX ret	/* update message length */
-
-mk_sdtr_max_offset:
-/*
- * We're initiating sync negotiation, so request the max offset we can (15 or 8)
- */
-	/* Talking to a WIDE device? */
-	test	SCSIRATE, WIDEXFER	jnz wmax_offset	
-	mvi	DINDIR, MAX_OFFSET_8BIT
-	jmp	mk_sdtr_done
-
-wmax_offset:
-	mvi	DINDIR, MAX_OFFSET_16BIT
-	jmp	mk_sdtr_done
-
-mk_wdtr_16bit:
-	mvi	ARG_1,BUS_16_BIT
-mk_wdtr:
-	mvi	DINDIR,1		/* extended message */
-	mvi	DINDIR,2		/* extended message length = 2 */
-	mvi	DINDIR,3		/* WDTR code */
-	mov	DINDIR,ARG_1		/* bus width */
-
-	add	MSG_LEN,COMP_MSG0,DINDEX ret	/* update message length */
-	
-sdtr_to_rate:
-	call	ndx_dtr			/* index scratch space for target */
-	shr	A,SINDIR,0x4
-	dec	SINDEX			/* Preserve SINDEX */
-	and	A,0x7
-	clr	RETURN_1
-sdtr_to_rate_loop:
-	test	A,0x0f	jz sdtr_to_rate_done
-	add	RETURN_1,0x19
-	dec	A	
-	jmp	sdtr_to_rate_loop
-sdtr_to_rate_done:
-	shr	RETURN_1,0x2
-	add	RETURN_1,0x19
-	test	SXFRCTL0,ULTRAEN jz return
-	shr	RETURN_1,0x1
-return:
-	ret

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov