aic79xx.seq

linux-2.6.15.6

	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	SCB_TASK_ATTRIBUTE, SCB_XFERLEN_ODD jnz mesgin_done;
	SET_SEQINTCODE(IGN_WIDE_RES)
	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;

/*
 * Complete the current FIFO's SCB if data for this same
 * SCB is not transferring in the other FIFO.
 */
SET_SRC_MODE	M_DFF1;
SET_DST_MODE	M_DFF1;
pkt_complete_scb_if_fifos_idle:
	bmov	ARG_1, SCBPTR, 2;
	mvi	DFFSXFRCTL, CLRCHN;
	SET_MODE(M_SCSI, M_SCSI)
	bmov	SCBPTR, ARG_1, 2;
	test	SCB_FIFO_USE_COUNT, 0xFF jnz return;
queue_scb_completion:
	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:
	/*
	 * Restore SCB TAG since we reuse this field
	 * in the sequencer.  We don't want to corrupt
	 * it on the host.
	 */
	bmov	SCB_TAG, SCBPTR, 2;
	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:     
	if ((ahd->bugs & AHD_EARLY_REQ_BUG) != 0) {
		/*
		 * Don't ignore persistent REQ assertions just because
		 * they were asserted within the bus settle delay window.
		 * This allows us to tolerate devices like the GEM318
		 * that violate the SCSI spec.  We are careful not to
		 * count REQ while we are waiting for it to fall during
		 * an async phase due to our asserted ACK.  Each
		 * sequencer instruction takes ~25ns, so the REQ must
		 * last at least 100ns in order to be counted as a true
		 * REQ.
		 */
		test	SCSIPHASE, 0xFF jnz phase_locked;
		test	SCSISIGI, ACKI jnz phase_lock;
		test	SCSISIGI, REQI jz phase_lock;
		test	SCSIPHASE, 0xFF jnz phase_locked;
		test	SCSISIGI, ACKI jnz phase_lock;
		test	SCSISIGI, REQI jz phase_lock;
phase_locked:
	} else {
		test	SCSIPHASE, 0xFF jz .;
	}
	test	SSTAT1, SCSIPERR jnz phase_lock;
phase_lock_latch_phase:
	and	LASTPHASE, PHASE_MASK, SCSISIGI ret;