patch-2.4.22 linux-2.4.22/drivers/scsi/aic79xx/aic79xx.seq

Next file: linux-2.4.22/drivers/scsi/aic79xx/aic79xx_core.c
Previous file: linux-2.4.22/drivers/scsi/aic79xx/aic79xx.reg
Back to the patch index
Back to the overall index

diff -urN linux-2.4.21/drivers/scsi/aic79xx/aic79xx.seq linux-2.4.22/drivers/scsi/aic79xx/aic79xx.seq
@@ -1,1889 +0,0 @@
-/*
- * Adaptec U320 device driver firmware for Linux and FreeBSD.
- *
- * Copyright (c) 1994-2001 Justin T. Gibbs.
- * Copyright (c) 2000-2002 Adaptec Inc.
- * 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, this list of conditions, and the following disclaimer,
- *    without modification.
- * 2. Redistributions in binary form must reproduce at minimum a disclaimer
- *    substantially similar to the "NO WARRANTY" disclaimer below
- *    ("Disclaimer") and any redistribution must be conditioned upon
- *    including a substantially similar Disclaimer requirement for further
- *    binary redistribution.
- * 3. Neither the names of the above-listed copyright holders nor the names
- *    of any contributors may be used to endorse or promote products derived
- *    from this software without specific prior written permission.
- *
- * Alternatively, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") version 2 as published by the Free
- * Software Foundation.
- *
- * NO WARRANTY
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.
- *
- * $FreeBSD$
- */
-
-VERSION = "$Id: //depot/aic7xxx/aic7xxx/aic79xx.seq#78 $"
-PATCH_ARG_LIST = "struct ahd_softc *ahd"
-PREFIX = "ahd_"
-
-#include "aic79xx.reg"
-#include "scsi_message.h"
-
-restart:
-if ((ahd->bugs & AHD_INTCOLLISION_BUG) != 0) {
-	test	SEQINTCODE, 0xFF jz idle_loop;
-	SET_SEQINTCODE(NO_SEQINT)
-}
-
-idle_loop:
-
-	if ((ahd->bugs & AHD_INTCOLLISION_BUG) != 0) {
-		/*
-		 * Convert ERROR status into a sequencer
-		 * interrupt to handle the case of an
-		 * interrupt collision on the hardware
-		 * setting of HWERR.
-		 */
-		test	ERROR, 0xFF jz no_error_set;
-		SET_SEQINTCODE(SAW_HWERR)
-no_error_set:
-	}
-	SET_MODE(M_SCSI, M_SCSI)
-	test	SCSISEQ0, ENSELO|ENARBO jnz idle_loop_checkbus;
-	test	SEQ_FLAGS2, SELECTOUT_QFROZEN jnz idle_loop_checkbus;
-	cmp	WAITING_TID_HEAD[1], SCB_LIST_NULL je idle_loop_checkbus;
-	/*
-	 * ENSELO is cleared by a SELDO, so we must test for SELDO
-	 * one last time.
-	 */
-BEGIN_CRITICAL;
-	test	SSTAT0, SELDO jnz select_out;
-END_CRITICAL;
-	call	start_selection;
-idle_loop_checkbus:
-BEGIN_CRITICAL;
-	test	SSTAT0, SELDO jnz select_out;
-END_CRITICAL;
-	test	SSTAT0, SELDI jnz select_in;
-	test	SCSIPHASE, ~DATA_PHASE_MASK jz idle_loop_check_nonpackreq;
-	test	SCSISIGO, ATNO jz idle_loop_check_nonpackreq;
-	call	unexpected_nonpkt_phase_find_ctxt;
-idle_loop_check_nonpackreq:
-	test	SSTAT2, NONPACKREQ jz . + 2;
-	call	unexpected_nonpkt_phase_find_ctxt;
-	call	idle_loop_gsfifo_in_scsi_mode;
-	call	idle_loop_service_fifos;
-	call	idle_loop_cchan;
-	jmp	idle_loop;
-
-BEGIN_CRITICAL;
-idle_loop_gsfifo:
-	SET_MODE(M_SCSI, M_SCSI)
-idle_loop_gsfifo_in_scsi_mode:
-	test	LQISTAT2, LQIGSAVAIL jz return;
-	/*
-	 * We have received good status for this transaction.  There may
-	 * still be data in our FIFOs draining to the host.  Setup
-	 * monitoring of the draining process or complete the SCB.
-	 */
-good_status_IU_done:
-	bmov	SCBPTR, GSFIFO, 2;
-	clr	SCB_SCSI_STATUS;
-	/*
-	 * If a command completed before an attempted task management
-	 * function completed, notify the host after disabling any
-	 * pending select-outs.
-	 */
-	test	SCB_TASK_MANAGEMENT, 0xFF jz gsfifo_complete_normally;
-	test	SSTAT0, SELDO|SELINGO jnz . + 2;
-	and	SCSISEQ0, ~ENSELO;
-	SET_SEQINTCODE(TASKMGMT_CMD_CMPLT_OKAY)
-gsfifo_complete_normally:
-	or	SCB_CONTROL, STATUS_RCVD;
-
-	/*
-	 * Since this status did not consume a FIFO, we have to
-	 * be a bit more dilligent in how we check for FIFOs pertaining
-	 * to this transaction.  There are three states that a FIFO still
-	 * transferring data may be in.
-	 *
-	 * 1) Configured and draining to the host, with a pending CLRCHN.
-	 * 2) Configured and draining to the host, no pending CLRCHN.
-	 * 3) Pending cfg4data, fifo not empty.
-	 *
-	 * Cases 1 and 2 can be detected by noticing that a longjmp is
-	 * active for the FIFO and LONGJMP_SCB matches our SCB.  In this
-	 * case, we allow the routine servicing the FIFO to complete the SCB.
-	 * 
-	 * Case 3 implies either a pending or yet to occur save data
-	 * pointers for this same context in the other FIFO.  So, if
-	 * we detect case 2, we will properly defer the post of the SCB
-	 * and achieve the desired result.  The pending cfg4data will
-	 * notice that status has been received and complete the SCB.
-	 */
-	test	SCB_SGPTR, SG_LIST_NULL jz good_status_check_fifos;
-	/*
-	 * All segments have been loaded (or no data transfer), so
-	 * it is safe to complete the command.  Since this was a
-	 * cheap command to check for completion, loop to see if
-	 * more entries can be removed from the GSFIFO.
-	 */
-	call	complete;
-END_CRITICAL;
-	jmp	idle_loop_gsfifo_in_scsi_mode;
-BEGIN_CRITICAL;
-good_status_check_fifos:
-	clc;
-	bmov	ARG_1, SCBPTR, 2;
-	SET_MODE(M_DFF0, M_DFF0)
-	call	check_fifo;
-	jc	return;
-	SET_MODE(M_DFF1, M_DFF1)
-	call	check_fifo;
-	jc	return;
-	SET_MODE(M_SCSI, M_SCSI)
-	jmp	queue_scb_completion;
-END_CRITICAL;
-
-idle_loop_service_fifos:
-	SET_MODE(M_DFF0, M_DFF0)
-	test	LONGJMP_ADDR[1], INVALID_ADDR jnz idle_loop_next_fifo;
-	call	longjmp;
-idle_loop_next_fifo:
-	SET_MODE(M_DFF1, M_DFF1)
-	test	LONGJMP_ADDR[1], INVALID_ADDR jz longjmp;
-	ret;
-
-idle_loop_cchan:
-	SET_MODE(M_CCHAN, M_CCHAN)
-	test	QOFF_CTLSTA, HS_MAILBOX_ACT jz	hs_mailbox_empty;
-	mov	LOCAL_HS_MAILBOX, HS_MAILBOX;
-	or	QOFF_CTLSTA, HS_MAILBOX_ACT;
-hs_mailbox_empty:
-BEGIN_CRITICAL;
-	test	CCSCBCTL, CCARREN|CCSCBEN jz scbdma_idle;
-	test	CCSCBCTL, CCSCBDIR jnz fetch_new_scb_inprog;
-	test	CCSCBCTL, CCSCBDONE jz return;
-END_CRITICAL;
-	/* FALLTHROUGH */
-scbdma_tohost_done:
-	test	CCSCBCTL, CCARREN jz fill_qoutfifo_dmadone;
-	/*
-	 * A complete SCB upload requires no intervention.
-	 * The SCB is already on the COMPLETE_SCB list
-	 * and its completion notification will now be
-	 * handled just like any other SCB.
-	 */
-	and	CCSCBCTL, ~(CCARREN|CCSCBEN) ret;
-fill_qoutfifo_dmadone:
-	and	CCSCBCTL, ~(CCARREN|CCSCBEN);
-	call	qoutfifo_updated;
-	mvi	COMPLETE_SCB_DMAINPROG_HEAD[1], SCB_LIST_NULL;
-	bmov	QOUTFIFO_NEXT_ADDR, SCBHADDR, 4;
-	test	QOFF_CTLSTA, SDSCB_ROLLOVR jz return;
-	bmov	QOUTFIFO_NEXT_ADDR, SHARED_DATA_ADDR, 4;
-	xor	QOUTFIFO_ENTRY_VALID_TAG, QOUTFIFO_ENTRY_VALID_TOGGLE ret;
-
-qoutfifo_updated:
-	/*
-	 * If there are more commands waiting to be dma'ed
-	 * to the host, always coaless.  Otherwise honor the
-	 * host's wishes.
-	 */
-	cmp	COMPLETE_DMA_SCB_HEAD[1], SCB_LIST_NULL jne coaless_by_count;
-	cmp	COMPLETE_SCB_HEAD[1], SCB_LIST_NULL jne coaless_by_count;
-	test	LOCAL_HS_MAILBOX, ENINT_COALESS jz issue_cmdcmplt;
-
-	/*
-	 * If we have relatively few commands outstanding, don't
-	 * bother waiting for another command to complete.
-	 */
-	test	CMDS_PENDING[1], 0xFF jnz coaless_by_count;
-	/* Add -1 so that jnc means <= not just < */
-	add	A, -1, INT_COALESSING_MINCMDS;
-	add	NONE, A, CMDS_PENDING;
-	jnc	issue_cmdcmplt;
-	
-	/*
-	 * If coalessing, only coaless up to the limit
-	 * provided by the host driver.
-	 */
-coaless_by_count:
-	mov	A, INT_COALESSING_MAXCMDS;
-	add	NONE, A, INT_COALESSING_CMDCOUNT;
-	jc	issue_cmdcmplt;
-	/*
-	 * If the timer is not currently active,
-	 * fire it up.
-	 */
-	test	INTCTL, SWTMINTMASK jz return;
-	bmov	SWTIMER, INT_COALESSING_TIMER, 2;
-	mvi	CLRSEQINTSTAT, CLRSEQ_SWTMRTO;
-	or	INTCTL, SWTMINTEN|SWTIMER_START;
-	and	INTCTL, ~SWTMINTMASK ret;
-
-issue_cmdcmplt:
-	mvi	INTSTAT, CMDCMPLT;
-	clr	INT_COALESSING_CMDCOUNT;
-	or	INTCTL, SWTMINTMASK ret;
-
-BEGIN_CRITICAL;
-fetch_new_scb_inprog:
-	test	CCSCBCTL, ARRDONE jz return;
-fetch_new_scb_done:
-	and	CCSCBCTL, ~(CCARREN|CCSCBEN);
-	bmov	REG0, SCBPTR, 2;
-	clr	A;
-	add	CMDS_PENDING, 1;
-	adc	CMDS_PENDING[1], A;
-	/* Update the next SCB address to download. */
-	bmov	NEXT_QUEUED_SCB_ADDR, SCB_NEXT_SCB_BUSADDR, 4;
-	mvi	SCB_NEXT[1], SCB_LIST_NULL;
-	mvi	SCB_NEXT2[1], SCB_LIST_NULL;
-	/* Increment our position in the QINFIFO. */
-	mov	NONE, SNSCB_QOFF;
-	/*
-	 * SCBs that want to send messages are always
-	 * queued independently.  This ensures that they
-	 * are at the head of the SCB list to select out
-	 * to a target and we will see the MK_MESSAGE flag.
-	 */
-	test	SCB_CONTROL, MK_MESSAGE jnz first_new_target_scb;
-	shr	SINDEX, 3, SCB_SCSIID;
-	and	SINDEX, ~0x1;
-	mvi	SINDEX[1], (WAITING_SCB_TAILS >> 8);
-	bmov	DINDEX, SINDEX, 2;
-	bmov	SCBPTR, SINDIR, 2;
-	bmov	DINDIR, REG0, 2;
-	cmp	SCBPTR[1], SCB_LIST_NULL je first_new_target_scb;
-	bmov	SCB_NEXT, REG0, 2 ret;
-first_new_target_scb:
-	cmp	WAITING_TID_HEAD[1], SCB_LIST_NULL je first_new_scb;
-	bmov	SCBPTR, WAITING_TID_TAIL, 2;
-	bmov	SCB_NEXT2, REG0, 2;
-	bmov	WAITING_TID_TAIL, REG0, 2 ret;
-first_new_scb:
-	bmov	WAITING_TID_HEAD, REG0, 2;
-	bmov	WAITING_TID_TAIL, REG0, 2 ret;
-END_CRITICAL;
-
-scbdma_idle:
-	/*
-	 * Give precedence to downloading new SCBs to execute
-	 * unless select-outs are currently frozen.
-	 */
-	test	SEQ_FLAGS2, SELECTOUT_QFROZEN jnz . + 2;
-BEGIN_CRITICAL;
-	test	QOFF_CTLSTA, NEW_SCB_AVAIL jnz fetch_new_scb;
-	cmp	COMPLETE_DMA_SCB_HEAD[1], SCB_LIST_NULL jne dma_complete_scb;
-	cmp	COMPLETE_SCB_HEAD[1], SCB_LIST_NULL je return;
-	/* FALLTHROUGH */
-fill_qoutfifo:
-	/*
-	 * Keep track of the SCBs we are dmaing just
-	 * in case the DMA fails or is aborted.
-	 */
-	mov	A, QOUTFIFO_ENTRY_VALID_TAG;
-	bmov	COMPLETE_SCB_DMAINPROG_HEAD, COMPLETE_SCB_HEAD, 2;
-	mvi	CCSCBCTL, CCSCBRESET;
-	bmov	SCBHADDR, QOUTFIFO_NEXT_ADDR, 4;
-	bmov	SCBPTR, COMPLETE_SCB_HEAD, 2;
-fill_qoutfifo_loop:
-	mov	CCSCBRAM, SCBPTR;
-	or	CCSCBRAM, A, SCBPTR[1];
-	mov	NONE, SDSCB_QOFF;
-	inc	INT_COALESSING_CMDCOUNT;
-	add	CMDS_PENDING, -1;
-	adc	CMDS_PENDING[1], -1;
-	cmp	SCB_NEXT_COMPLETE[1], SCB_LIST_NULL je fill_qoutfifo_done;
-	cmp	CCSCBADDR, CCSCBADDR_MAX je fill_qoutfifo_done;
-	test	QOFF_CTLSTA, SDSCB_ROLLOVR jnz fill_qoutfifo_done;
-	bmov	SCBPTR, SCB_NEXT_COMPLETE, 2;
-	jmp	fill_qoutfifo_loop;
-fill_qoutfifo_done:
-	mov	SCBHCNT, CCSCBADDR;
-	mvi	CCSCBCTL, CCSCBEN|CCSCBRESET;
-	bmov	COMPLETE_SCB_HEAD, SCB_NEXT_COMPLETE, 2;
-	mvi	SCB_NEXT_COMPLETE[1], SCB_LIST_NULL ret;
-
-fetch_new_scb:
-	bmov	SCBHADDR, NEXT_QUEUED_SCB_ADDR, 4;
-	mvi	CCARREN|CCSCBEN|CCSCBDIR|CCSCBRESET jmp dma_scb;
-dma_complete_scb:
-	bmov	SCBPTR, COMPLETE_DMA_SCB_HEAD, 2;
-	bmov	SCBHADDR, SCB_BUSADDR, 4;
-	mvi	CCARREN|CCSCBEN|CCSCBRESET call dma_scb;
-	/*
-	 * Now that we've started the DMA, push us onto
-	 * the normal completion queue to have our SCBID
-	 * posted to the kernel.
-	 */
-	bmov	COMPLETE_DMA_SCB_HEAD, SCB_NEXT_COMPLETE, 2;
-	bmov	SCB_NEXT_COMPLETE, COMPLETE_SCB_HEAD, 2;
-	bmov	COMPLETE_SCB_HEAD, SCBPTR, 2 ret;
-END_CRITICAL;
-
-/*
- * Either post or fetch an SCB from host memory.  The caller
- * is responsible for polling for transfer completion.
- *
- * Prerequisits: Mode == M_CCHAN
- *		 SINDEX contains CCSCBCTL flags
- *		 SCBHADDR set to Host SCB address
- *		 SCBPTR set to SCB src location on "push" operations
- */
-SET_SRC_MODE	M_CCHAN;
-SET_DST_MODE	M_CCHAN;
-dma_scb:
-	mvi	SCBHCNT, SCB_TRANSFER_SIZE;
-	mov	CCSCBCTL, SINDEX ret;
-
-BEGIN_CRITICAL;
-setjmp_setscb:
-	bmov	LONGJMP_SCB, SCBPTR, 2;
-setjmp:
-	bmov	LONGJMP_ADDR, STACK, 2 ret;
-setjmp_inline:
-	bmov	LONGJMP_ADDR, STACK, 2;
-longjmp:
-	bmov	STACK, LONGJMP_ADDR, 2 ret;
-END_CRITICAL;
-
-/*************************** Chip Bug Work Arounds ****************************/
-/*
- * Must disable interrupts when setting the mode pointer
- * register as an interrupt occurring mid update will
- * fail to store the new mode value for restoration on
- * an iret.
- */
-if ((ahd->bugs & AHD_SET_MODE_BUG) != 0) {
-set_mode_work_around:
-	mvi	SEQINTCTL, INTVEC1DSL;
-	mov	MODE_PTR, SINDEX;
-	clr	SEQINTCTL ret;
-
-toggle_dff_mode_work_around:
-	mvi	SEQINTCTL, INTVEC1DSL;
-	xor	MODE_PTR, MK_MODE(M_DFF1, M_DFF1);
-	clr	SEQINTCTL ret;
-}
-
-
-if ((ahd->bugs & AHD_INTCOLLISION_BUG) != 0) {
-set_seqint_work_around:
-	mov	SEQINTCODE, SINDEX;
-	mvi	SEQINTCODE, NO_SEQINT ret;
-}
-
-/************************ Packetized LongJmp Routines *************************/
-SET_SRC_MODE	M_SCSI;
-SET_DST_MODE	M_SCSI;
-start_selection:
-BEGIN_CRITICAL;
-	if ((ahd->bugs & AHD_SENT_SCB_UPDATE_BUG) != 0) {
-		/*
-		 * Razor #494
-		 * Rev A hardware fails to update LAST/CURR/NEXTSCB
-		 * correctly after a packetized selection in several
-		 * situations:
-		 *
-		 * 1) If only one command existed in the queue, the
-		 *    LAST/CURR/NEXTSCB are unchanged.
-		 *
-		 * 2) In a non QAS, protocol allowed phase change,
-		 *    the queue is shifted 1 too far.  LASTSCB is
-		 *    the last SCB that was correctly processed.
-		 * 
-		 * 3) In the QAS case, if the full list of commands
-		 *    was successfully sent, NEXTSCB is NULL and neither
-		 *    CURRSCB nor LASTSCB can be trusted.  We must
-		 *    manually walk the list counting MAXCMDCNT elements
-		 *    to find the last SCB that was sent correctly.
-		 *
-		 * To simplify the workaround for this bug in SELDO
-		 * handling, we initialize LASTSCB prior to enabling
-		 * selection so we can rely on it even for case #1 above.
-		 */
-		bmov	LASTSCB, WAITING_TID_HEAD, 2;
-	}
-	bmov	CURRSCB, WAITING_TID_HEAD, 2;
-	bmov	SCBPTR, WAITING_TID_HEAD, 2;
-	shr	SELOID, 4, SCB_SCSIID;
-	/*
-	 * If we want to send a message to the device, ensure
-	 * we are selecting with atn irregardless of our packetized
-	 * agreement.  Since SPI4 only allows target reset or PPR
-	 * messages if this is a packetized connection, the change
-	 * to our negotiation table entry for this selection will
-	 * be cleared when the message is acted on.
-	 */
-	test	SCB_CONTROL, MK_MESSAGE jz . + 3;
-	mov	NEGOADDR, SELOID;
-	or	NEGCONOPTS, ENAUTOATNO;
-	or	SCSISEQ0, ENSELO ret;
-END_CRITICAL;
-
-/*
- * Allocate a FIFO for a non-packetized transaction.
- * In RevA hardware, both FIFOs must be free before we
- * can allocate a FIFO for a non-packetized transaction.
- */
-allocate_fifo_loop:
-	/*
-	 * Do whatever work is required to free a FIFO.
-	 */
-	call	idle_loop_service_fifos;
-	SET_MODE(M_SCSI, M_SCSI)
-allocate_fifo:
-	if ((ahd->bugs & AHD_NONPACKFIFO_BUG) != 0) {
-		and	A, FIFO0FREE|FIFO1FREE, DFFSTAT;
-		cmp	A, FIFO0FREE|FIFO1FREE jne allocate_fifo_loop;
-	} else {
-		test	DFFSTAT, FIFO1FREE jnz allocate_fifo1;
-		test	DFFSTAT, FIFO0FREE jz allocate_fifo_loop;
-		mvi	DFFSTAT, B_CURRFIFO_0;
-		SET_MODE(M_DFF0, M_DFF0)
-		bmov	SCBPTR, ALLOCFIFO_SCBPTR, 2 ret;
-	}
-SET_SRC_MODE	M_SCSI;
-SET_DST_MODE	M_SCSI;
-allocate_fifo1:
-	mvi	DFFSTAT, CURRFIFO_1;
-	SET_MODE(M_DFF1, M_DFF1)
-	bmov	SCBPTR, ALLOCFIFO_SCBPTR, 2 ret;
-
-/*
- * We have been reselected as an initiator
- * or selected as a target.
- */
-SET_SRC_MODE	M_SCSI;
-SET_DST_MODE	M_SCSI;
-select_in:
-	if ((ahd->bugs & AHD_BUSFREEREV_BUG) != 0) {
-		/*
-		 * This exposes a window whereby a
-		 * busfree just after a selection will
-		 * be missed, but there is no other safe
-		 * way to enable busfree detection if
-		 * the busfreerev function is broken.
-		 */
-		mvi	CLRSINT1,CLRBUSFREE;
-		or	SIMODE1, ENBUSFREE;
-	}
-	or	SXFRCTL0, SPIOEN;
-	and	SAVED_SCSIID, SELID_MASK, SELID;
-	and	A, OID, IOWNID;
-	or	SAVED_SCSIID, A;
-	mvi	CLRSINT0, CLRSELDI;
-	jmp	ITloop;
-
-/*
- * We have successfully selected out.
- *
- * Clear SELDO.
- * Dequeue all SCBs sent from the waiting queue
- * Requeue all SCBs *not* sent to the tail of the waiting queue
- * Take Razor #494 into account for above.
- *
- * In Packetized Mode:
- *	Return to the idle loop.  Our interrupt handler will take
- *	care of any incoming L_Qs.
- *
- * In Non-Packetize Mode:
- *	Continue to our normal state machine.
- */
-SET_SRC_MODE	M_SCSI;
-SET_DST_MODE	M_SCSI;
-select_out:
-BEGIN_CRITICAL;
-	/* Clear out all SCBs that have been successfully sent. */
-	if ((ahd->bugs & AHD_SENT_SCB_UPDATE_BUG) != 0) {
-		/*
-		 * For packetized, the LQO manager clears ENSELO on
-		 * the assertion of SELDO.  If we are non-packetized,
-		 * LASTSCB and CURRSCB are acuate.
-		 */
-		test	SCSISEQ0, ENSELO jnz use_lastscb;
-
-		/*
-		 * The update is correct for LQOSTAT1 errors.  All
-		 * but LQOBUSFREE are handled by kernel interrupts.
-		 * If we see LQOBUSFREE, return to the idle loop.
-		 * Once we are out of the select_out critical section,
-		 * the kernel will cleanup the LQOBUSFREE and we will
-		 * eventually restart the selection if appropriate.
-		 */
-		test	LQOSTAT1, LQOBUSFREE jnz idle_loop;
-
-		/*
-		 * On a phase change oustside of packet boundaries,
-		 * LASTSCB points to the currently active SCB context
-		 * on the bus.
-		 */
-		test	LQOSTAT2, LQOPHACHGOUTPKT jnz use_lastscb;
-
-		/*
-		 * If the hardware has traversed the whole list, NEXTSCB
-		 * will be NULL, CURRSCB and LASTSCB cannot be trusted,
-		 * but MAXCMDCNT is accurate.  If we stop part way through
-		 * the list or only had one command to issue, NEXTSCB[1] is
-		 * not NULL and LASTSCB is the last command to go out.
-		 */
-		cmp	NEXTSCB[1], SCB_LIST_NULL jne use_lastscb;
-
-		/*
-		 * Brute force walk.
-		 */
-		bmov	SCBPTR, WAITING_TID_HEAD, 2;
-		mvi	SEQINTCTL, INTVEC1DSL;
-		mvi	MODE_PTR, MK_MODE(M_CFG, M_CFG);
-		mov	A, MAXCMDCNT;
-		mvi	MODE_PTR, MK_MODE(M_SCSI, M_SCSI);
-		clr	SEQINTCTL;
-find_lastscb_loop:
-		dec	A;
-		test	A, 0xFF jz found_last_sent_scb;
-		bmov	SCBPTR, SCB_NEXT, 2;
-		jmp	find_lastscb_loop;
-use_lastscb:
-		bmov	SCBPTR, LASTSCB, 2;
-found_last_sent_scb:
-		bmov	CURRSCB, SCBPTR, 2;
-curscb_ww_done:
-	} else {
-		/*
-		 * Untested - Verify with Rev B.
-		 */
-		bmov	SCBPTR, CURRSCB, 2;
-	}
-
-	/*
-	 * Requeue any SCBs not sent, to the tail of the waiting Q.
-	 */
-	cmp	SCB_NEXT[1], SCB_LIST_NULL je select_out_list_done;
-
-	/*
-	 * We know that neither the per-TID list nor the list of
-	 * TIDs is empty.  Use this knowledge to our advantage.
-	 */
-	bmov	REG0, SCB_NEXT, 2;
-	bmov	SCBPTR, WAITING_TID_TAIL, 2;
-	bmov	SCB_NEXT2, REG0, 2;
-	bmov	WAITING_TID_TAIL, REG0, 2;
-	jmp	select_out_inc_tid_q;
-
-select_out_list_done:
-	/*
-	 * The whole list made it.  Just clear our TID's tail pointer
-	 * unless we were queued independently due to our need to
-	 * send a message.
-	 */
-	test	SCB_CONTROL, MK_MESSAGE jnz select_out_inc_tid_q;
-	shr	DINDEX, 3, SCB_SCSIID;
-	or	DINDEX, 1;	/* Want only the second byte */
-	mvi	DINDEX[1], ((WAITING_SCB_TAILS) >> 8);
-	mvi	DINDIR, SCB_LIST_NULL;
-select_out_inc_tid_q:
-	bmov	SCBPTR, WAITING_TID_HEAD, 2;
-	bmov	WAITING_TID_HEAD, SCB_NEXT2, 2;
-	cmp	WAITING_TID_HEAD[1], SCB_LIST_NULL jne . + 2;
-	mvi	WAITING_TID_TAIL[1], SCB_LIST_NULL;
-	bmov	SCBPTR, CURRSCB, 2;
-	mvi	CLRSINT0, CLRSELDO;
-	test	LQOSTAT2, LQOPHACHGOUTPKT jnz unexpected_nonpkt_phase;
-	test	LQOSTAT1, LQOPHACHGINPKT jnz unexpected_nonpkt_phase;
-
-	/*
-	 * If this is a packetized connection, return to our
-	 * idle_loop and let our interrupt handler deal with
-	 * any connection setup/teardown issues.  The only
-	 * exceptions are the case of MK_MESSAGE and task management
-	 * SCBs.
-	 */
-	if ((ahd->bugs & AHD_LQO_ATNO_BUG) != 0) {
-		/*
-		 * In the A, the LQO manager transitions to LQOSTOP0 even if
-		 * we have selected out with ATN asserted and the target
-		 * REQs in a non-packet phase.
-		 */
-		test 	SCB_CONTROL, MK_MESSAGE jz select_out_no_message;
-		test	SCSISIGO, ATNO jnz select_out_non_packetized;
-select_out_no_message:
-	}
-	test	LQOSTAT2, LQOSTOP0 jz select_out_non_packetized;
-	test	SCB_TASK_MANAGEMENT, 0xFF jz idle_loop;
-	SET_SEQINTCODE(TASKMGMT_FUNC_COMPLETE)
-	jmp	idle_loop;
-
-select_out_non_packetized:
-	/* Non packetized request. */
-	and     SCSISEQ0, ~ENSELO;
-	if ((ahd->bugs & AHD_BUSFREEREV_BUG) != 0) {
-		/*
-		 * This exposes a window whereby a
-		 * busfree just after a selection will
-		 * be missed, but there is no other safe
-		 * way to enable busfree detection if
-		 * the busfreerev function is broken.
-		 */
-		mvi	CLRSINT1,CLRBUSFREE;
-		or	SIMODE1, ENBUSFREE;
-	}
-	mov	SAVED_SCSIID, SCB_SCSIID;
-	mov	SAVED_LUN, SCB_LUN;
-	mvi	SEQ_FLAGS, NO_CDB_SENT;
-END_CRITICAL;
-	or	SXFRCTL0, SPIOEN;
-
-	/*
-	 * As soon as we get a successful selection, the target
-	 * should go into the message out phase since we have ATN
-	 * asserted.
-	 */
-	mvi	MSG_OUT, MSG_IDENTIFYFLAG;
-
-	/*
-	 * Main loop for information transfer phases.  Wait for the
-	 * target to assert REQ before checking MSG, C/D and I/O for
-	 * the bus phase.
-	 */
-mesgin_phasemis:
-ITloop:
-	call	phase_lock;
-
-	mov	A, LASTPHASE;
-
-	test	A, ~P_DATAIN_DT	jz p_data;
-	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;
-
-	SET_SEQINTCODE(BAD_PHASE)
-	jmp	ITloop;			/* Try reading the bus again. */
-
-/*
- * Command phase.  Set up the DMA registers and let 'er rip.
- */
-p_command:
-	test	SEQ_FLAGS, NOT_IDENTIFIED jz p_command_okay;
-	SET_SEQINTCODE(PROTO_VIOLATION)
-p_command_okay:
-	test	MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1))
-		jnz p_command_allocate_fifo;
-	/*
-	 * Command retry.  Free our current FIFO and
-	 * re-allocate a FIFO so transfer state is
-	 * reset.
-	 */
-SET_SRC_MODE	M_DFF1;
-SET_DST_MODE	M_DFF1;
-	mvi	DFFSXFRCTL, RSTCHN|CLRSHCNT;
-	SET_MODE(M_SCSI, M_SCSI)
-p_command_allocate_fifo:
-	bmov	ALLOCFIFO_SCBPTR, SCBPTR, 2;
-	call	allocate_fifo;
-SET_SRC_MODE	M_DFF1;
-SET_DST_MODE	M_DFF1;
-	add	NONE, -17, SCB_CDB_LEN;
-	jnc	p_command_embedded;
-p_command_from_host:
-	bmov	HADDR[0], SCB_CDB_PTR, 11;
-	mvi	SG_CACHE_PRE, LAST_SEG;
-	mvi	DFCNTRL, (PRELOADEN|SCSIEN|HDMAEN);
-	jmp	p_command_xfer;
-p_command_embedded:
-	bmov	SHCNT[0], SCB_CDB_LEN,  1;
-	bmov	DFDAT, SCB_CDB_STORE, 16; 
-	mvi	DFCNTRL, SCSIEN;
-p_command_xfer:
-	and	SEQ_FLAGS, ~NO_CDB_SENT;
-	test	DFCNTRL, SCSIEN jnz .;
-	/*
-	 * DMA Channel automatically disabled.
-	 * Don't allow a data phase if the command
-	 * was not fully transferred.
-	 */
-	test	SSTAT2, SDONE jnz ITloop;
-	or	SEQ_FLAGS, NO_CDB_SENT;
-	jmp	ITloop;
-
-
-/*
- * Status phase.  Wait for the data byte to appear, then read it
- * and store it into the SCB.
- */
-SET_SRC_MODE	M_SCSI;
-SET_DST_MODE	M_SCSI;
-p_status:
-	test	SEQ_FLAGS,NOT_IDENTIFIED jnz mesgin_proto_violation;
-p_status_okay:
-	mov	SCB_SCSI_STATUS, SCSIDAT;
-	or	SCB_CONTROL, STATUS_RCVD;
-	jmp	ITloop;
-
-/*
- * Message out phase.  If MSG_OUT is MSG_IDENTIFYFLAG, build a full
- * indentify message sequence and send it to the target.  The host may
- * override this behavior by setting the MK_MESSAGE bit in the SCB
- * control byte.  This will cause us to interrupt the host and allow
- * it to handle the message phase completely on its own.  If the bit
- * associated with this target is set, we will also interrupt the host,
- * thereby allowing it to send a message on the next selection regardless
- * of the transaction being sent.
- * 
- * If MSG_OUT is == HOST_MSG, also interrupt the host and take a message.
- * This is done to allow the host to send messages outside of an identify
- * sequence while protecting the seqencer from testing the MK_MESSAGE bit
- * on an SCB that might not be for the current nexus. (For example, a
- * BDR message in responce to a bad reselection would leave us pointed to
- * an SCB that doesn't have anything to do with the current target).
- *
- * Otherwise, treat MSG_OUT as a 1 byte message to send (abort, abort tag,
- * bus device reset).
- *
- * When there are no messages to send, MSG_OUT should be set to MSG_NOOP,
- * in case the target decides to put us in this phase for some strange
- * reason.
- */
-p_mesgout_retry:
-	/* Turn on ATN for the retry */
-	mvi	SCSISIGO, ATNO;
-p_mesgout:
-	mov	SINDEX, MSG_OUT;
-	cmp	SINDEX, MSG_IDENTIFYFLAG jne p_mesgout_from_host;
-	test	SCB_CONTROL,MK_MESSAGE	jnz host_message_loop;
-p_mesgout_identify:
-	or	SINDEX, MSG_IDENTIFYFLAG|DISCENB, SCB_LUN;
-	test	SCB_CONTROL, DISCENB jnz . + 2;
-	and	SINDEX, ~DISCENB;
-/*
- * Send a tag message if TAG_ENB is set in the SCB control block.
- * Use SCB_NONPACKET_TAG as the tag value.
- */
-p_mesgout_tag:
-	test	SCB_CONTROL,TAG_ENB jz  p_mesgout_onebyte;
-	mov	SCSIDAT, SINDEX;	/* Send the identify message */
-	call	phase_lock;
-	cmp	LASTPHASE, P_MESGOUT	jne p_mesgout_done;
-	and	SCSIDAT,TAG_ENB|SCB_TAG_TYPE,SCB_CONTROL;
-	call	phase_lock;
-	cmp	LASTPHASE, P_MESGOUT	jne p_mesgout_done;
-	mov	SCBPTR jmp p_mesgout_onebyte;
-/*
- * Interrupt the driver, and allow it to handle this message
- * phase and any required retries.
- */
-p_mesgout_from_host:
-	cmp	SINDEX, HOST_MSG	jne p_mesgout_onebyte;
-	jmp	host_message_loop;
-
-p_mesgout_onebyte:
-	mvi	CLRSINT1, CLRATNO;
-	mov	SCSIDAT, SINDEX;
-
-/*
- * If the next bus phase after ATN drops is message out, it means
- * that the target is requesting that the last message(s) be resent.
- */
-	call	phase_lock;
-	cmp	LASTPHASE, P_MESGOUT	je p_mesgout_retry;
-
-p_mesgout_done:
-	mvi	CLRSINT1,CLRATNO;	/* Be sure to turn ATNO off */
-	mov	LAST_MSG, MSG_OUT;
-	mvi	MSG_OUT, MSG_NOOP;	/* No message left */
-	jmp	ITloop;
-
-/*
- * Message in phase.  Bytes are read using Automatic PIO mode.
- */
-p_mesgin:
-	/* read the 1st message byte */
-	mvi	ACCUM		call inb_first;
-
-	test	A,MSG_IDENTIFYFLAG	jnz mesgin_identify;
-	cmp	A,MSG_DISCONNECT	je mesgin_disconnect;
-	cmp	A,MSG_SAVEDATAPOINTER	je mesgin_sdptrs;
-	cmp	ALLZEROS,A		je mesgin_complete;
-	cmp	A,MSG_RESTOREPOINTERS	je mesgin_rdptrs;
-	cmp	A,MSG_IGN_WIDE_RESIDUE	je mesgin_ign_wide_residue;
-	cmp	A,MSG_NOOP		je mesgin_done;
-
-/*
- * Pushed message loop to allow the kernel to
- * run it's own message state engine.  To avoid an
- * extra nop instruction after signaling the kernel,
- * we perform the phase_lock before checking to see
- * if we should exit the loop and skip the phase_lock
- * in the ITloop.  Performing back to back phase_locks
- * shouldn't hurt, but why do it twice...
- */
-host_message_loop:
-	call	phase_lock;	/* Benign the first time through. */
-	SET_SEQINTCODE(HOST_MSG_LOOP)
-	cmp	RETURN_1, EXIT_MSG_LOOP	je ITloop;
-	cmp	RETURN_1, CONT_MSG_LOOP_WRITE	jne . + 3;
-	mov	SCSIDAT, RETURN_2;
-	jmp	host_message_loop;
-	/* Must be CONT_MSG_LOOP_READ */
-	mov	NONE, SCSIDAT;	/* ACK Byte */
-	jmp	host_message_loop;
-
-mesgin_ign_wide_residue:
-	mov	SAVED_MODE, MODE_PTR;
-	SET_MODE(M_SCSI, M_SCSI)
-	shr	NEGOADDR, 4, SAVED_SCSIID;
-	mov	A, NEGCONOPTS;
-	RESTORE_MODE(SAVED_MODE)
-	test	A, WIDEXFER jz mesgin_reject;
-	/* Pull the residue byte */
-	mvi	REG0	call inb_next;
-	cmp	REG0, 0x01 jne mesgin_reject;
-	test	SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz . + 2;
-	test	DATA_COUNT_ODD, 0x1	jz mesgin_done;
-	jmp	mesgin_done;
-
-mesgin_proto_violation:
-	SET_SEQINTCODE(PROTO_VIOLATION)
-	jmp	mesgin_done;
-mesgin_reject:
-	mvi	MSG_MESSAGE_REJECT	call mk_mesg;
-mesgin_done:
-	mov	NONE,SCSIDAT;		/*dummy read from latch to ACK*/
-	jmp	ITloop;
-
-#define INDEX_DISC_LIST(scsiid, lun)					\
-	and	A, 0xC0, scsiid;					\
-	or	SCBPTR, A, lun;						\
-	clr	SCBPTR[1];						\
-	and	SINDEX, 0x30, scsiid;					\
-	shr	SINDEX, 3;	/* Multiply by 2 */			\
-	add	SINDEX, (SCB_DISCONNECTED_LISTS & 0xFF);		\
-	mvi	SINDEX[1], ((SCB_DISCONNECTED_LISTS >> 8) & 0xFF)
-
-mesgin_identify:
-	/*
-	 * Determine whether a target is using tagged or non-tagged
-	 * transactions by first looking at the transaction stored in
-	 * the per-device, disconnected array.  If there is no untagged
-	 * transaction for this target, this must be a tagged transaction.
-	 */
-	and	SAVED_LUN, MSG_IDENTIFY_LUNMASK, A;
-	INDEX_DISC_LIST(SAVED_SCSIID, SAVED_LUN);
-	bmov	DINDEX, SINDEX, 2;
-	bmov	REG0, SINDIR, 2;
-	cmp	REG0[1], SCB_LIST_NULL je snoop_tag;
-	/* Untagged.  Clear the busy table entry and setup the SCB. */
-	bmov	DINDIR, ALLONES, 2;
-	bmov	SCBPTR, REG0, 2;
-	jmp	setup_SCB;
-
-/*
- * Here we "snoop" the bus looking for a SIMPLE QUEUE TAG message.
- * If we get one, we use the tag returned to find the proper
- * SCB.  After receiving the tag, look for the SCB at SCB locations tag and
- * tag + 256.
- */
-snoop_tag:
-	if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
-		or	SEQ_FLAGS, 0x80;
-	}
-	mov	NONE, SCSIDAT;		/* ACK Identify MSG */
-	call	phase_lock;
-	if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
-		or	SEQ_FLAGS, 0x1;
-	}
-	cmp	LASTPHASE, P_MESGIN	jne not_found_ITloop;
-	if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
-		or	SEQ_FLAGS, 0x2;
-	}
-	cmp	SCSIBUS, MSG_SIMPLE_Q_TAG jne not_found;
-get_tag:
-	clr	SCBPTR[1];
-	mvi	SCBPTR	call inb_next;	/* tag value */
-verify_scb:
-	test	SCB_CONTROL,DISCONNECTED jz verify_other_scb;
-	mov	A, SAVED_SCSIID;
-	cmp	SCB_SCSIID, A jne verify_other_scb;
-	mov	A, SAVED_LUN;
-	cmp	SCB_LUN, A je setup_SCB_disconnected;
-verify_other_scb:
-	xor	SCBPTR[1], 1;
-	test	SCBPTR[1], 0xFF jnz verify_scb;
-	jmp	not_found;
-
-/*
- * Ensure that the SCB the tag points to is for
- * an SCB transaction to the reconnecting target.
- */
-setup_SCB:
-	if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
-		or	SEQ_FLAGS, 0x10;
-	}
-	test	SCB_CONTROL,DISCONNECTED jz not_found;
-setup_SCB_disconnected:
-	and	SCB_CONTROL,~DISCONNECTED;
-	clr	SEQ_FLAGS;	/* make note of IDENTIFY */
-	test	SCB_SGPTR, SG_LIST_NULL jnz . + 3;
-	bmov	ALLOCFIFO_SCBPTR, SCBPTR, 2;
-	call	allocate_fifo;
-	/* See if the host wants to send a message upon reconnection */
-	test	SCB_CONTROL, MK_MESSAGE jz mesgin_done;
-	mvi	HOST_MSG	call mk_mesg;
-	jmp	mesgin_done;
-
-not_found:
-	SET_SEQINTCODE(NO_MATCH)
-	jmp	mesgin_done;
-
-not_found_ITloop:
-	SET_SEQINTCODE(NO_MATCH)
-	jmp	ITloop;
-
-/*
- * We received a "command complete" message.  Put the SCB on the complete
- * queue and trigger a completion interrupt via the idle loop.  Before doing
- * so, check to see if there
- * is a residual or the status byte is something other than STATUS_GOOD (0).
- * In either of these conditions, we upload the SCB back to the host so it can
- * process this information.  In the case of a non zero status byte, we 
- * additionally interrupt the kernel driver synchronously, allowing it to
- * decide if sense should be retrieved.  If the kernel driver wishes to request
- * sense, it will fill the kernel SCB with a request sense command, requeue
- * it to the QINFIFO and tell us not to post to the QOUTFIFO by setting 
- * RETURN_1 to SEND_SENSE.
- */
-mesgin_complete:
-
-	/*
-	 * If ATN is raised, we still want to give the target a message.
-	 * Perhaps there was a parity error on this last message byte.
-	 * Either way, the target should take us to message out phase
-	 * and then attempt to complete the command again.  We should use a
-	 * critical section here to guard against a timeout triggering
-	 * for this command and setting ATN while we are still processing
-	 * the completion.
-	test	SCSISIGI, ATNI jnz mesgin_done;
-	 */
-
-	/*
-	 * If we are identified and have successfully sent the CDB,
-	 * any status will do.  Optimize this fast path.
-	 */
-	test	SCB_CONTROL, STATUS_RCVD jz mesgin_proto_violation;
-	test	SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT jz complete_accepted;
-
-	/*
-	 * If the target never sent an identify message but instead went
-	 * to mesgin to give an invalid message, let the host abort us.
-	 */
-	test	SEQ_FLAGS, NOT_IDENTIFIED jnz mesgin_proto_violation;
-
-	/*
-	 * If we recevied good status but never successfully sent the
-	 * cdb, abort the command.
-	 */
-	test	SCB_SCSI_STATUS,0xff	jnz complete_accepted;
-	test	SEQ_FLAGS, NO_CDB_SENT jnz mesgin_proto_violation;
-complete_accepted:
-
-	/*
-	 * See if we attempted to deliver a message but the target ingnored us.
-	 */
-	test	SCB_CONTROL, MK_MESSAGE jz complete_nomsg;
-	SET_SEQINTCODE(MKMSG_FAILED)
-complete_nomsg:
-	call	queue_scb_completion;
-	jmp	await_busfree;
-
-freeze_queue:
-	/* Cancel any pending select-out. */
-	test	SSTAT0, SELDO|SELINGO jnz . + 2;
-	and	SCSISEQ0, ~ENSELO;
-	mov	ACCUM_SAVE, A;
-	clr	A;
-	add	QFREEZE_COUNT, 1;
-	adc	QFREEZE_COUNT[1], A;
-	or	SEQ_FLAGS2, SELECTOUT_QFROZEN;
-	mov	A, ACCUM_SAVE ret;
-
-queue_arg1_scb_completion:
-	SET_MODE(M_SCSI, M_SCSI)
-	bmov	SCBPTR, ARG_1, 2;
-queue_scb_completion:
-	if ((ahd->bugs & AHD_ABORT_LQI_BUG) == 0) {
-		/*
-		 * Set MK_MESSAGE to trigger an abort should this SCB
-		 * be referenced by a target even though it is not currently
-		 * active.
-		 */
-		or	SCB_CONTROL, MK_MESSAGE;
-	}
-	test	SCB_SCSI_STATUS,0xff	jnz bad_status;
-	/*
-	 * Check for residuals
-	 */
-	test	SCB_SGPTR, SG_LIST_NULL jnz complete;	/* No xfer */
-	test	SCB_SGPTR, SG_FULL_RESID jnz upload_scb;/* Never xfered */
-	test	SCB_RESIDUAL_SGPTR, SG_LIST_NULL jz upload_scb;
-complete:
-	bmov	SCB_NEXT_COMPLETE, COMPLETE_SCB_HEAD, 2;
-	bmov	COMPLETE_SCB_HEAD, SCBPTR, 2 ret;
-bad_status:
-	cmp	SCB_SCSI_STATUS, STATUS_PKT_SENSE je upload_scb;
-	call	freeze_queue;
-upload_scb:
-	bmov	SCB_NEXT_COMPLETE, COMPLETE_DMA_SCB_HEAD, 2;
-	bmov	COMPLETE_DMA_SCB_HEAD, SCBPTR, 2;
-	or	SCB_SGPTR, SG_STATUS_VALID ret;
-
-/*
- * Is it a disconnect message?  Set a flag in the SCB to remind us
- * and await the bus going free.  If this is an untagged transaction
- * store the SCB id for it in our untagged target table for lookup on
- * a reselction.
- */
-mesgin_disconnect:
-	/*
-	 * If ATN is raised, we still want to give the target a message.
-	 * Perhaps there was a parity error on this last message byte
-	 * or we want to abort this command.  Either way, the target
-	 * should take us to message out phase and then attempt to
-	 * disconnect again.
-	 * XXX - Wait for more testing.
-	test	SCSISIGI, ATNI jnz mesgin_done;
-	 */
-	test	SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT
-		jnz mesgin_proto_violation;
-	or	SCB_CONTROL,DISCONNECTED;
-	test	SCB_CONTROL, TAG_ENB jnz await_busfree;
-queue_disc_scb:
-	bmov	REG0, SCBPTR, 2;
-	INDEX_DISC_LIST(SAVED_SCSIID, SAVED_LUN);
-	bmov	DINDEX, SINDEX, 2;
-	bmov	DINDIR, REG0, 2;
-	bmov	SCBPTR, REG0, 2;
-	/* FALLTHROUGH */
-await_busfree:
-	and	SIMODE1, ~ENBUSFREE;
-	if ((ahd->bugs & AHD_BUSFREEREV_BUG) == 0) {
-		/*
-		 * In the BUSFREEREV_BUG case, the
-		 * busfree status was cleared at the
-		 * beginning of the connection.
-		 */
-		mvi	CLRSINT1,CLRBUSFREE;
-	}
-	mov	NONE, SCSIDAT;		/* Ack the last byte */
-	test	MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1))
-		jnz await_busfree_not_m_dff;
-SET_SRC_MODE	M_DFF1;
-SET_DST_MODE	M_DFF1;
-await_busfree_clrchn:
-	mvi	DFFSXFRCTL, CLRCHN;
-await_busfree_not_m_dff:
-	call	clear_target_state;
-	test	SSTAT1,REQINIT|BUSFREE	jz .;
-	test	SSTAT1, BUSFREE jnz idle_loop;
-	SET_SEQINTCODE(MISSED_BUSFREE)
-
-
-/*
- * Save data pointers message:
- * 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.
- * Ack the message as soon as possible.
- */
-SET_SRC_MODE	M_DFF1;
-SET_DST_MODE	M_DFF1;
-mesgin_sdptrs:
-	mov	NONE,SCSIDAT;		/*dummy read from latch to ACK*/
-	test	SEQ_FLAGS, DPHASE	jz ITloop;
-	call	save_pointers;
-	jmp	ITloop;
-
-save_pointers:
-	/*
-	 * If we are asked to save our position at the end of the
-	 * transfer, just mark us at the end rather than perform a
-	 * full save.
-	 */
-	test	SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz save_pointers_full;
-	or	SCB_SGPTR, SG_LIST_NULL ret;
-
-save_pointers_full:
-	/*
-	 * The SCB_DATAPTR becomes the current SHADDR.
-	 * All other information comes directly from our residual
-	 * state.
-	 */
-	bmov	SCB_DATAPTR, SHADDR, 8;
-	bmov	SCB_DATACNT, SCB_RESIDUAL_DATACNT, 8 ret;
-
-/*
- * 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.  We also reset/reallocate the FIFO to make
- * sure we have a clean start for the next data or command phase.
- */
-mesgin_rdptrs:
-	and	SEQ_FLAGS, ~DPHASE;
-	test	MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1)) jnz msgin_rdptrs_get_fifo;
-	mvi	DFFSXFRCTL, RSTCHN|CLRSHCNT;
-	SET_MODE(M_SCSI, M_SCSI)
-msgin_rdptrs_get_fifo:
-	call	allocate_fifo;
-	jmp	mesgin_done;
-
-clear_target_state:
-	mvi	LASTPHASE, P_BUSFREE;
-	/* clear target specific flags */
-	mvi	SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT ret;
-
-phase_lock:     
-	test	SCSIPHASE, 0xFF jz .;
-	test	SSTAT1, SCSIPERR jnz phase_lock;
-phase_lock_latch_phase:
-	and	LASTPHASE, PHASE_MASK, SCSISIGI ret;
-
-/*
- * Functions to read data in Automatic PIO mode.
- *
- * 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:
-	mov	NONE,SCSIDAT;		/*dummy read from latch to ACK*/
-inb_next_wait:
-	/*
-	 * If there is a parity error, wait for the kernel to
-	 * see the interrupt and prepare our message response
-	 * before continuing.
-	 */
-	test	SCSIPHASE, 0xFF jz .;
-	test	SSTAT1, SCSIPERR jnz inb_next_wait;
-inb_next_check_phase:
-	and	LASTPHASE, PHASE_MASK, SCSISIGI;
-	cmp	LASTPHASE, P_MESGIN jne mesgin_phasemis;
-inb_first:
-	clr	DINDEX[1];
-	mov	DINDEX,SINDEX;
-	mov	DINDIR,SCSIBUS	ret;		/*read byte directly from bus*/
-inb_last:
-	mov	NONE,SCSIDAT ret;		/*dummy read from latch to ACK*/
-
-mk_mesg:
-	mvi	SCSISIGO, ATNO;
-	mov	MSG_OUT,SINDEX ret;
-
-SET_SRC_MODE	M_DFF1;
-SET_DST_MODE	M_DFF1;
-disable_ccsgen:
-	test	SG_STATE, FETCH_INPROG jz disable_ccsgen_fetch_done;
-	clr	CCSGCTL;
-disable_ccsgen_fetch_done:
-	clr	SG_STATE ret;
-
-service_fifo:
-	/*
-	 * Do we have any prefetch left???
-	 */
-	test	SG_STATE, SEGS_AVAIL jnz idle_sg_avail;
-
-	/*
-	 * Can this FIFO have access to the S/G cache yet?
-	 */
-	test	CCSGCTL, SG_CACHE_AVAIL jz return;
-
-	/* Did we just finish fetching segs? */
-	test	CCSGCTL, CCSGDONE jnz idle_sgfetch_complete;
-
-	/* Are we actively fetching segments? */
-	test	CCSGCTL, CCSGENACK jnz return;
-
-	/*
-	 * We fetch a "cacheline aligned" and sized amount of data
-	 * so we don't end up referencing a non-existant page.
-	 * Cacheline aligned is in quotes because the kernel will
-	 * set the prefetch amount to a reasonable level if the
-	 * cacheline size is unknown.
-	 */
-	bmov	SGHADDR, SCB_RESIDUAL_SGPTR, 4;
-	mvi	SGHCNT, SG_PREFETCH_CNT;
-	if ((ahd->bugs & AHD_REG_SLOW_SETTLE_BUG) != 0) {
-		/*
-		 * Need two instruction between "touches" of SGHADDR.
-		 */
-		nop;
-	}
-	and	SGHADDR[0], SG_PREFETCH_ALIGN_MASK, SCB_RESIDUAL_SGPTR;
-	mvi	CCSGCTL, CCSGEN|SG_CACHE_AVAIL|CCSGRESET;
-	or	SG_STATE, FETCH_INPROG ret;
-idle_sgfetch_complete:
-	/*
-	 * Guard against SG_CACHE_AVAIL activating during sg fetch
-	 * request in the other FIFO.
-	 */
-	test	SG_STATE, FETCH_INPROG jz return;
-	clr	CCSGCTL;
-	and	CCSGADDR, SG_PREFETCH_ADDR_MASK, SCB_RESIDUAL_SGPTR;
-	mvi	SG_STATE, SEGS_AVAIL|LOADING_NEEDED;
-idle_sg_avail:
-	/* Does the hardware have space for another SG entry? */
-	test	DFSTATUS, PRELOAD_AVAIL jz return;
-	if ((ahd->flags & AHD_64BIT_ADDRESSING) != 0) {
-		bmov	HADDR, CCSGRAM, 8;
-	} else {
-		bmov 	HADDR, CCSGRAM, 4;
-	}
-	bmov	HCNT, CCSGRAM, 3;
-	test	HCNT[0], 0x1 jz . + 2;
-	xor	DATA_COUNT_ODD, 0x1;
-	bmov	SCB_RESIDUAL_DATACNT[3], CCSGRAM, 1;
-	if ((ahd->flags & AHD_39BIT_ADDRESSING) != 0) {
-		and	HADDR[4], SG_HIGH_ADDR_BITS, SCB_RESIDUAL_DATACNT[3];
-	}
-	if ((ahd->flags & AHD_64BIT_ADDRESSING) != 0) {
-		/* Skip 4 bytes of pad. */
-		add	CCSGADDR, 4;
-	}
-sg_advance:
-	clr	A;			/* add sizeof(struct scatter) */
-	add	SCB_RESIDUAL_SGPTR[0],SG_SIZEOF;
-	adc	SCB_RESIDUAL_SGPTR[1],A;
-	adc	SCB_RESIDUAL_SGPTR[2],A;
-	adc	SCB_RESIDUAL_SGPTR[3],A;
-	mov	SINDEX, SCB_RESIDUAL_SGPTR[0];
-	test	DATA_COUNT_ODD, 0x1 jz . + 2;
-	or	SINDEX, ODD_SEG;
-	test	SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jz . + 3;
-	or	SINDEX, LAST_SEG;
-	clr	SG_STATE;
-	mov	SG_CACHE_PRE, SINDEX;
-	/*
-	 * Load the segment.  Or in HDMAEN here too
-	 * just in case HDMAENACK has not come true
-	 * by the time this segment is loaded.  If
-	 * HDMAENACK is not true, this or will disable
-	 * HDMAEN mid-transfer.  We do not want to simply
-	 * mvi our original settings as SCSIEN automatically
-	 * de-asserts and we don't want to accidentally
-	 * re-enable it.
-	 */
-	if ((ahd->features & AHD_NEW_DFCNTRL_OPTS) != 0) {
-		/*
-		 * Use SCSIENWRDIS so that SCSIEN is never
-		 * modified by this operation.
-		 */
-		or	DFCNTRL, PRELOADEN|SCSIENWRDIS|HDMAEN;
-	} else {
-		or	DFCNTRL, PRELOADEN|HDMAEN;
-	}
-	/*
-	 * Do we have another segment in the cache?
-	 */
-	add	NONE, SG_PREFETCH_CNT_LIMIT, CCSGADDR;
-	jnc	return;
-	and	SG_STATE, ~SEGS_AVAIL ret;
-
-/*
- * Initialize the DMA address and counter from the SCB.
- */
-load_first_seg:
-	bmov	HADDR, SCB_DATAPTR, 11;
-	and	DATA_COUNT_ODD, 0x1, SCB_DATACNT[0];
-	and	REG_ISR, ~SG_FULL_RESID, SCB_SGPTR[0];
-	test	SCB_DATACNT[3], SG_LAST_SEG jz . + 2;
-	or	REG_ISR, LAST_SEG;
-	test	DATA_COUNT_ODD, 0x1 jz . + 2;
-	or	REG_ISR, ODD_SEG;
-	mov	SG_CACHE_PRE, REG_ISR;
-	mvi	DFCNTRL, (PRELOADEN|SCSIEN|HDMAEN);
-	/*
-	 * Since we've are entering a data phase, we will
-	 * rely on the SCB_RESID* fields.  Initialize the
-	 * residual and clear the full residual flag.
-	 */
-	and	SCB_SGPTR[0], ~SG_FULL_RESID;
-	bmov	SCB_RESIDUAL_DATACNT[3], SCB_DATACNT[3], 5;
-	/* If we need more S/G elements, tell the idle loop */
-	test	SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jnz . + 2;
-	mvi	SG_STATE, LOADING_NEEDED ret;
-	clr	SG_STATE ret;
-
-p_data_handle_xfer:
-	call	setjmp_setscb;
-	test	SG_STATE, LOADING_NEEDED jnz service_fifo;
-p_data_clear_handler:
-	or	LONGJMP_ADDR[1], INVALID_ADDR ret;
-
-p_data:
-	test	SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT	jz p_data_allowed;
-	SET_SEQINTCODE(PROTO_VIOLATION)
-p_data_allowed:
- 
-	test	SEQ_FLAGS, DPHASE	jz data_phase_initialize;
-
-	/*
-	 * If we re-enter the data phase after going through another
-	 * phase, our transfer location has almost certainly been
-	 * corrupted by the interveining, non-data, transfers.  Ask
-	 * the host driver to fix us up based on the transfer residual
-	 * unless we already know that we should be bitbucketing.
-	 */
-	test	SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jnz p_data_bitbucket;
-	SET_SEQINTCODE(PDATA_REINIT)
-	jmp	data_phase_inbounds;
-
-p_data_bitbucket:
-	/*
-	 * Turn on `Bit Bucket' mode, wait until the target takes
-	 * us to another phase, and then notify the host.
-	 */
-	mov	SAVED_MODE, MODE_PTR;
-	test	MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1))
-		jnz bitbucket_not_m_dff;
-	/*
-	 * Ensure that any FIFO contents are cleared out and the
-	 * FIFO free'd prior to starting the BITBUCKET.  BITBUCKET
-	 * doesn't discard data already in the FIFO.
-	 */
-	mvi	DFFSXFRCTL, RSTCHN|CLRSHCNT;
-	SET_MODE(M_SCSI, M_SCSI)
-bitbucket_not_m_dff:
-	or	SXFRCTL1,BITBUCKET;
-	/* Wait for non-data phase. */
-	test	SCSIPHASE, ~DATA_PHASE_MASK jz .;
-	and	SXFRCTL1, ~BITBUCKET;
-	RESTORE_MODE(SAVED_MODE)
-SET_SRC_MODE	M_DFF1;
-SET_DST_MODE	M_DFF1;
-	SET_SEQINTCODE(DATA_OVERRUN)
-	jmp	ITloop;
-
-data_phase_initialize:
-	test	SCB_SGPTR[0], SG_LIST_NULL jnz p_data_bitbucket;
-	call	load_first_seg;
-data_phase_inbounds:
-	/* We have seen a data phase at least once. */
-	or	SEQ_FLAGS, DPHASE;
-	mov	SAVED_MODE, MODE_PTR;
-	test	SG_STATE, LOADING_NEEDED jz data_group_dma_loop;
-	call	p_data_handle_xfer;
-data_group_dma_loop:
-	/*
-	 * The transfer is complete if either the last segment
-	 * completes or the target changes phase.  Both conditions
-	 * will clear SCSIEN.
-	 */
-	call	idle_loop_service_fifos;
-	call	idle_loop_cchan;
-	call	idle_loop_gsfifo;
-	RESTORE_MODE(SAVED_MODE)
-	test	DFCNTRL, SCSIEN jnz data_group_dma_loop;
-
-data_group_dmafinish:
-	/*
-	 * The transfer has terminated either due to a phase
-	 * change, and/or the completion of the last segment.
-	 * We have two goals here.  Do as much other work
-	 * as possible while the data fifo drains on a read
-	 * and respond as quickly as possible to the standard
-	 * messages (save data pointers/disconnect and command
-	 * complete) that usually follow a data phase.
-	 */
-	call	calc_residual;
-
-	/*
-	 * Go ahead and shut down the DMA engine now.
-	 */
-	test	DFCNTRL, DIRECTION jnz data_phase_finish;
-data_group_fifoflush:
-	if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
-		or	DFCNTRL, FIFOFLUSH;
-	}
-	/*
-	 * We have enabled the auto-ack feature.  This means
-	 * that the controller may have already transferred
-	 * some overrun bytes into the data FIFO and acked them
-	 * on the bus.  The only way to detect this situation is
-	 * to wait for LAST_SEG_DONE to come true on a completed
-	 * transfer and then test to see if the data FIFO is
-	 * non-empty.  We know there is more data yet to transfer
-	 * if SG_LIST_NULL is not yet set, thus there cannot be
-	 * an overrun.
-	 */
-	test	SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz data_phase_finish;
-	test	SG_CACHE_SHADOW, LAST_SEG_DONE jz .;
-	test	DFSTATUS, FIFOEMP jnz data_phase_finish;
-	/* Overrun */
-	jmp	p_data;
-data_phase_finish:
-	/*
-	 * If the target has left us in data phase, loop through
-	 * the dma code again.  We will only loop if there is a
-	 * data overrun.  
-	 */
-	if ((ahd->flags & AHD_TARGETROLE) != 0) {
-		test	SSTAT0, TARGET jnz data_phase_done;
-	}
-	if ((ahd->flags & AHD_INITIATORROLE) != 0) {
-		test	SSTAT1, REQINIT jz .;
-		test	SCSIPHASE, DATA_PHASE_MASK jnz p_data;
-	}
-
-data_phase_done:
-	/* Kill off any pending prefetch */
-	call	disable_ccsgen;
-	or 	LONGJMP_ADDR[1], INVALID_ADDR;
-
-	if ((ahd->flags & AHD_TARGETROLE) != 0) {
-		test	SEQ_FLAGS, DPHASE_PENDING jz ITloop;
-		/*
-		and	SEQ_FLAGS, ~DPHASE_PENDING;
-		 * For data-in phases, wait for any pending acks from the
-		 * initiator before changing phase.  We only need to
-		 * send Ignore Wide Residue messages for data-in phases.
-		test	DFCNTRL, DIRECTION jz target_ITloop;
-		test	SSTAT1, REQINIT	jnz .;
-		test	DATA_COUNT_ODD, 0x1 jz target_ITloop;
-		SET_MODE(M_SCSI, M_SCSI)
-		test	NEGCONOPTS, WIDEXFER jz target_ITloop;
-		 */
-		/*
-		 * Issue an Ignore Wide Residue Message.
-		mvi	P_MESGIN|BSYO call change_phase;
-		mvi	MSG_IGN_WIDE_RESIDUE call target_outb;
-		mvi	1 call target_outb;
-		jmp	target_ITloop;
-		 */
-	} else {
-		jmp	ITloop;
-	}
-
-/*
- * We assume that, even though data may still be
- * transferring to the host, that the SCSI side of
- * the DMA engine is now in a static state.  This
- * allows us to update our notion of where we are
- * in this transfer.
- *
- * If, by chance, we stopped before being able
- * to fetch additional segments for this transfer,
- * yet the last S/G was completely exhausted,
- * call our idle loop until it is able to load
- * another segment.  This will allow us to immediately
- * pickup on the next segment on the next data phase.
- *
- * If we happened to stop on the last segment, then
- * our residual information is still correct from
- * the idle loop and there is no need to perform
- * any fixups.
- */
-calc_residual:
-	test	SG_CACHE_SHADOW, LAST_SEG jz residual_before_last_seg;
-	/* Record if we've consumed all S/G entries */
-	test	MDFFSTAT, SHVALID	jz . + 2;
-	bmov	SCB_RESIDUAL_DATACNT, SHCNT, 3 ret;
-	or	SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL ret;
-residual_before_last_seg:
-	test    MDFFSTAT, SHVALID	jnz sgptr_fixup;
-	/*
-	 * Can never happen from an interrupt as the packetized
-	 * hardware will only interrupt us once SHVALID or
-	 * LAST_SEG_DONE.
-	 */
-	call	idle_loop_service_fifos;
-	RESTORE_MODE(SAVED_MODE)
-	jmp	calc_residual;
-
-sgptr_fixup:
-	/*
-	 * Fixup the residual next S/G pointer.  The S/G preload
-	 * feature of the chip allows us to load two elements
-	 * in addition to the currently active element.  We
-	 * store the bottom byte of the next S/G pointer in
-	 * the SG_CACHE_PTR register so we can restore the
-	 * correct value when the DMA completes.  If the next
-	 * sg ptr value has advanced to the point where higher
-	 * bytes in the address have been affected, fix them
-	 * too.
-	 */
-	test	SG_CACHE_SHADOW, 0x80 jz sgptr_fixup_done;
-	test	SCB_RESIDUAL_SGPTR[0], 0x80 jnz sgptr_fixup_done;
-	add	SCB_RESIDUAL_SGPTR[1], -1;
-	adc	SCB_RESIDUAL_SGPTR[2], -1; 
-	adc	SCB_RESIDUAL_SGPTR[3], -1;
-sgptr_fixup_done:
-	and	SCB_RESIDUAL_SGPTR[0], SG_ADDR_MASK, SG_CACHE_SHADOW;
-	clr	DATA_COUNT_ODD;
-	test	SG_CACHE_SHADOW, ODD_SEG jz . + 2;
-	or	DATA_COUNT_ODD, 0x1;
-	clr	SCB_RESIDUAL_DATACNT[3]; /* We are not the last seg */
-	bmov	SCB_RESIDUAL_DATACNT, SHCNT, 3 ret;
-
-export timer_isr:
-	call	issue_cmdcmplt;
-	mvi	CLRSEQINTSTAT, CLRSEQ_SWTMRTO;
-	if ((ahd->bugs & AHD_SET_MODE_BUG) != 0) {
-		/*
-		 * In H2A4, the mode pointer is not saved
-		 * for intvec2, but is restored on iret.
-		 * This can lead to the restoration of a
-		 * bogus mode ptr.  Manually clear the
-		 * intmask bits and do a normal return
-		 * to compensate.
-		 */
-		and	SEQINTCTL, ~(INTMASK2|INTMASK1) ret;
-	} else {
-		or	SEQINTCTL, IRET ret;
-	}
-
-export seq_isr:
-	nop;	/* Jumps in the first ISR instruction fail on Rev A. */
-	test	SEQINTSRC, CFG4DATA	jnz cfg4data_intr;
-	test	SEQINTSRC, CFG4ISTAT	jnz cfg4istat_intr;
-	test	SEQINTSRC, SAVEPTRS	jnz saveptr_intr;
-	test	SEQINTSRC, CFG4ICMD	jnz cfg4icmd_intr;
-	SET_SEQINTCODE(INVALID_SEQINT)
-
-/*
- * There are two types of save pointers interrupts:
- * The first is a snapshot save pointers where the current FIFO is not
- * active and contains a snapshot of the current poniter information.
- * This happens between packets in a stream for a single L_Q.  Since we
- * are not performing a pointer save, we can safely clear the channel
- * so it can be used for other transactions.
- *
- * The second case is a save pointers on an active FIFO which occurs
- * if the target changes to a new L_Q or busfrees/QAS' and the transfer
- * has a residual.  This should occur coincident with a ctxtdone.  We
- * disable the interrupt and allow our active routine to handle the
- * save.
- */
-saveptr_intr:
-	test	DFCNTRL, HDMAENACK jz snapshot_saveptr;
-	and	SEQIMODE, ~ENSAVEPTRS;
-	or	SEQINTCTL, IRET ret;
-snapshot_saveptr:
-	mvi	DFFSXFRCTL, CLRCHN;
-	or	SEQINTCTL, IRET ret;
-
-cfg4data_intr:
-	test	SCB_SGPTR[0], SG_LIST_NULL jnz pkt_handle_overrun;
-	call	load_first_seg;
-	call	pkt_handle_xfer;
-	or	SEQINTCTL, IRET ret;
-
-cfg4istat_intr:
-	call	freeze_queue;
-	add	NONE, -13, SCB_CDB_LEN;
-	jnc	cfg4istat_have_sense_addr;
-	test	SCB_CDB_LEN, SCB_CDB_LEN_PTR jnz cfg4istat_have_sense_addr;
-	/*
-	 * Host sets up address/count and enables transfer.
-	 */
-	SET_SEQINTCODE(CFG4ISTAT_INTR)
-	jmp	cfg4istat_setup_handler;
-cfg4istat_have_sense_addr:
-	bmov	HADDR, SCB_SENSE_BUSADDR, 4;
-	mvi	HCNT[1], (AHD_SENSE_BUFSIZE >> 8);
-	mvi	SG_CACHE_PRE, LAST_SEG;
-	mvi	DFCNTRL, PRELOADEN|SCSIEN|HDMAEN;
-cfg4istat_setup_handler:
-	/*
-	 * Status pkt is transferring to host.
-	 * Wait in idle loop for transfer to complete.
-	 * If a command completed before an attempted
-	 * task management function completed, notify the host.
-	 */
-	test	SCB_TASK_MANAGEMENT, 0xFF jz cfg4istat_no_taskmgmt_func;
-	SET_SEQINTCODE(TASKMGMT_CMD_CMPLT_OKAY)
-cfg4istat_no_taskmgmt_func:
-	call	pkt_handle_status;
-	or	SEQINTCTL, IRET ret;
-
-/*
- * See if the target has gone on in this context creating an
- * overrun condition.  For the write case, the hardware cannot
- * ack bytes until data are provided.  So, if the target begins
- * another  packet without changing contexts, implying we are
- * not sitting on a packet boundary, we are in an overrun
- * situation.  For the read case, the hardware will continue to
- * ack bytes into the FIFO, and may even ack the last overrun packet
- * into the FIFO.   If the FIFO should become non-empty, we are in
- * a read overrun case.
- */
-#define check_overrun							\
-	/* Not on a packet boundary. */					\
-	test 	MDFFSTAT, DLZERO jz pkt_handle_overrun;			\
-	test	DFSTATUS, FIFOEMP jz pkt_handle_overrun
-
-pkt_handle_xfer:
-	bmov	LONGJMP_SCB, SCBPTR, 2;
-	test	SG_STATE, LOADING_NEEDED jz pkt_last_seg;
-	call	setjmp;
-	test	SEQINTSRC, SAVEPTRS jnz pkt_saveptrs;
-	test	SCSIPHASE, ~DATA_PHASE_MASK jz . + 2;
-	test	SCSISIGO, ATNO jnz . + 2;
-	test	SSTAT2, NONPACKREQ jz pkt_service_fifo;
-	/*
-	 * Defer handling of this NONPACKREQ until we
-	 * can be sure it pertains to this FIFO.  SAVEPTRS
-	 * will not be asserted if the NONPACKREQ is for us,
-	 * so we must simulate it if shaddow is valid.  If
-	 * shaddow is not valid, keep running this FIFO until we
-	 * have satisfied the transfer by loading segments and
-	 * waiting for either shaddow valid or last_seg_done.
-	 */
-	test	MDFFSTAT, SHVALID jnz pkt_saveptrs;
-pkt_service_fifo:
-	test	SG_STATE, LOADING_NEEDED jnz service_fifo;
-pkt_last_seg:
-	call	setjmp;
-	test	SEQINTSRC, SAVEPTRS jnz pkt_saveptrs;
-	test	SG_CACHE_SHADOW, LAST_SEG_DONE jnz last_pkt_done;
-	test	SCSIPHASE, ~DATA_PHASE_MASK jz . + 2;
-	test	SCSISIGO, ATNO jnz . + 2;
-	test	SSTAT2, NONPACKREQ jz return;
-	test	MDFFSTAT, SHVALID jz return;
-	/* FALLTHROUGH */
-
-/*
- * Either a SAVEPTRS interrupt condition is pending for this FIFO
- * or we have a pending nonpackreq for this FIFO.  We differentiate
- * between the two by capturing the state of the SAVEPTRS interrupt
- * prior to clearing this status and executing the common code for
- * these two cases.
- */
-pkt_saveptrs:
-BEGIN_CRITICAL;
-	if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
-		or	DFCNTRL, FIFOFLUSH;
-	}
-	mov	REG0, SEQINTSRC;
-	call	calc_residual;
-	call	save_pointers;
-	mvi	CLRSEQINTSRC, CLRSAVEPTRS;
-	call	disable_ccsgen;
-	or	SEQIMODE, ENSAVEPTRS;
-	test	DFCNTRL, DIRECTION jnz pkt_saveptrs_check_status;
-	test	DFSTATUS, FIFOEMP jnz pkt_saveptrs_check_status;
-	/*
-	 * Keep a handler around for this FIFO until it drains
-	 * to the host to guarantee that we don't complete the
-	 * command to the host before the data arrives.
-	 */
-pkt_saveptrs_wait_fifoemp:
-	call	setjmp;
-	test	DFSTATUS, FIFOEMP jz return;
-pkt_saveptrs_check_status:
-	or	LONGJMP_ADDR[1], INVALID_ADDR;
-	test	REG0, SAVEPTRS jz unexpected_nonpkt_phase;
-	test	SCB_CONTROL, STATUS_RCVD jz pkt_saveptrs_clrchn;
-	jmp	last_pkt_complete;
-pkt_saveptrs_clrchn:
-	mvi	DFFSXFRCTL, CLRCHN ret;
-END_CRITICAL;
-
-last_pkt_done:
-BEGIN_CRITICAL;
-	if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
-		or	DFCNTRL, FIFOFLUSH;
-	}
-	test	SCB_CONTROL, STATUS_RCVD jz wait_pkt_end;
-	check_overrun;
-	or	SCB_SGPTR, SG_LIST_NULL;
-	/*
-	 * It is safe to skip the other FIFO check since
-	 * we defer CLRCHN on SAVEPTRS until all data in
-	 * the FIFO are seen by the host and a CFG4DATA
-	 * in this FIFO for the same context is held off
-	 * by hardware.
-	 */
-last_pkt_queue_scb:
-	or	LONGJMP_ADDR[1], INVALID_ADDR;
-	bmov	ARG_1, SCBPTR, 2;
-	mvi	DFFSXFRCTL, CLRCHN;
-	jmp	queue_arg1_scb_completion;
-
-last_pkt_complete:
-	bmov	ARG_1, SCBPTR, 2;
-	mvi	DFFSXFRCTL, CLRCHN;
-check_other_fifo:
-	clc;
-	TOGGLE_DFF_MODE
-	call	check_fifo;
-	jnc	queue_arg1_scb_completion;
-return:
-	ret;
-
-wait_pkt_end:
-	call	setjmp;
-END_CRITICAL;
-wait_pkt_end_loop:
-	test	SEQINTSRC, CTXTDONE jnz pkt_end;
-	check_overrun;
-	test	SSTAT2, NONPACKREQ jz return;
-	test	SEQINTSRC, CTXTDONE jz unexpected_nonpkt_phase;
-pkt_end:
-BEGIN_CRITICAL;
-	check_overrun;
-	or	LONGJMP_ADDR[1], INVALID_ADDR;
-	or	SCB_SGPTR, SG_LIST_NULL;
-	test	SCB_CONTROL, STATUS_RCVD jnz last_pkt_complete;
-	mvi	DFFSXFRCTL, CLRCHN ret;
-END_CRITICAL;
-
-check_status_overrun:
-	test	SHCNT[2], 0xFF jz status_IU_done;
-	SET_SEQINTCODE(STATUS_OVERRUN)
-	jmp	status_IU_done;
-pkt_handle_status:
-	call	setjmp_setscb;
-	test	MDFFSTAT, LASTSDONE jnz check_status_overrun;
-	test	SEQINTSRC, CTXTDONE jz return;
-status_IU_done:
-BEGIN_CRITICAL;
-	if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
-		or	DFCNTRL, FIFOFLUSH;
-	}
-	or	LONGJMP_ADDR[1], INVALID_ADDR;
-	mvi	SCB_SCSI_STATUS, STATUS_PKT_SENSE;
-	or	SCB_CONTROL, STATUS_RCVD;
-	jmp	last_pkt_complete;
-END_CRITICAL;
-
-SET_SRC_MODE	M_DFF0;
-SET_DST_MODE	M_DFF0;
-BEGIN_CRITICAL;
-check_fifo:
-	test	LONGJMP_ADDR[1], INVALID_ADDR jnz return;
-	mov	A, ARG_2;
-	cmp	LONGJMP_SCB[1], A	jne return;
-	mov	A, ARG_1;
-	cmp	LONGJMP_SCB[0], A	jne return;
-	stc	ret;
-END_CRITICAL;
-
-/*
- * Nonpackreq is a polled status.  It can come true in three situations:
- * we have received an L_Q, we have sent one or more L_Qs, or there is no
- * L_Q context associated with this REQ (REQ occurs immediately after a
- * (re)selection).  Routines that know that the context responsible for this
- * nonpackreq call directly into unexpected_nonpkt_phase.  In the case of the
- * top level idle loop, we exhaust all active contexts prior to determining that
- * we simply do not have the full I_T_L_Q for this phase.
- */
-unexpected_nonpkt_phase_find_ctxt:
-	/*
-	 * This nonpackreq is most likely associated with one of the tags
-	 * in a FIFO or an outgoing LQ.  Only treat it as an I_T only
-	 * nonpackreq if we've cleared out the FIFOs and handled any
-	 * pending SELDO.
-	 */
-SET_SRC_MODE	M_SCSI;
-SET_DST_MODE	M_SCSI;
-	and	A, FIFO1FREE|FIFO0FREE, DFFSTAT;
-	cmp	A, FIFO1FREE|FIFO0FREE jne return;
-	test	SSTAT0, SELDO jnz return;
-	mvi	SCBPTR[1], SCB_LIST_NULL;
-unexpected_nonpkt_phase:
-	test	MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1)) jnz . + 3;
-SET_SRC_MODE	M_DFF0;
-SET_DST_MODE	M_DFF0;
-	or	LONGJMP_ADDR[1], INVALID_ADDR;
-	mvi	DFFSXFRCTL, CLRCHN;
-	mvi	CLRSINT2, CLRNONPACKREQ;
-	test	SCSIPHASE, ~(MSG_IN_PHASE|MSG_OUT_PHASE) jnz illegal_phase;
-	SET_SEQINTCODE(ENTERING_NONPACK)
-	jmp	ITloop;
-
-illegal_phase:
-	SET_SEQINTCODE(ILLEGAL_PHASE)
-	jmp	ITloop;
-
-/*
- * We have entered an overrun situation.  If we have working
- * BITBUCKET, flip that on and let the hardware eat any overrun
- * data.  Otherwise use an overrun buffer in the host to simulate
- * BITBUCKET.
- */
-pkt_handle_overrun:
-	SET_SEQINTCODE(CFG4OVERRUN)
-	call	freeze_queue;
-	if ((ahd->bugs & AHD_PKT_BITBUCKET_BUG) == 0) {
-		or	DFFSXFRCTL, DFFBITBUCKET;
-SET_SRC_MODE	M_DFF1;
-SET_DST_MODE	M_DFF1;
-	} else {
-		call	load_overrun_buf;
-		mvi	DFCNTRL, (HDMAEN|SCSIEN|PRELOADEN);
-	}
-	call	setjmp;
-	if ((ahd->bugs & AHD_PKT_BITBUCKET_BUG) != 0) {
-		test	DFSTATUS, PRELOAD_AVAIL jz overrun_load_done;
-		call	load_overrun_buf;
-		or	DFCNTRL, PRELOADEN;
-overrun_load_done:
-		test	SEQINTSRC, CTXTDONE jnz pkt_overrun_end;
-	} else {
-		test	DFFSXFRCTL, DFFBITBUCKET jz pkt_overrun_end;
-	}
-	test	SSTAT2, NONPACKREQ jz return;
-pkt_overrun_end:
-	or	SCB_RESIDUAL_SGPTR, SG_OVERRUN_RESID;
-	test	SEQINTSRC, CTXTDONE jz unexpected_nonpkt_phase;
-	test	SCB_CONTROL, STATUS_RCVD jnz last_pkt_queue_scb;
-	mvi	DFFSXFRCTL, CLRCHN ret;
-
-if ((ahd->bugs & AHD_PKT_BITBUCKET_BUG) != 0) {
-load_overrun_buf:
-	/*
-	 * Load a dummy segment if preload space is available.
-	 */
-	mov 	HADDR[0], SHARED_DATA_ADDR;
-	add	HADDR[1], PKT_OVERRUN_BUFOFFSET, SHARED_DATA_ADDR[1];
-	mov	ACCUM_SAVE, A;
-	clr	A;
-	adc	HADDR[2], A, SHARED_DATA_ADDR[2];
-	adc	HADDR[3], A, SHARED_DATA_ADDR[3];
-	mov	A, ACCUM_SAVE;
-	bmov	HADDR[4], ALLZEROS, 4;
-	/* PKT_OVERRUN_BUFSIZE is a multiple of 256 */
-	clr	HCNT[0];
-	mvi	HCNT[1], ((PKT_OVERRUN_BUFSIZE >> 8) & 0xFF);
-	clr	HCNT[2] ret;
-}
-
-cfg4icmd_intr:
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)