NCR5380.c

			 * until ACK goes false.  Since the NCR5380 won't lower ACK
			 * until DACK is asserted, which won't happen unless we twiddle
			 * the DMA port or we take the NCR5380 out of DMA mode, we 
			 * can guarantee that we won't handshake another extra 
			 * byte.
			 */

			if (!(hostdata->flags & FLAG_NCR53C400)) {
				while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
				/* Wait for clean handshake */
				while (NCR5380_read(STATUS_REG) & SR_REQ);
				d[c - 1] = NCR5380_read(INPUT_DATA_REG);
			}
		}
#endif
	} else {
#ifdef DMA_WORKS_RIGHT
		foo = NCR5380_pwrite(instance, d, c);
#else
		int timeout;
		dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
		if (!(foo = NCR5380_pwrite(instance, d, c))) {
			/*
			 * Wait for the last byte to be sent.  If REQ is being asserted for 
			 * the byte we're interested, we'll ACK it and it will go false.  
			 */
			if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
				timeout = 20000;
				while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));

				if (!timeout)
					dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));

				if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
					hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
					if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
						hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
						dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
					}
				}
			} else {
				dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
				while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
				dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
			}
		}
#endif
	}
	NCR5380_write(MODE_REG, MR_BASE);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
		dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
		if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
			dprintk(NDEBUG_C400_PWRITE, ("53C400w:    got it, reading reset interrupt reg\n"));
			NCR5380_read(RESET_PARITY_INTERRUPT_REG);
		} else {
			printk("53C400w:    IRQ NOT THERE!\n");
		}
	}
	*data = d + c;
	*count = 0;
	*phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
#if defined(PSEUDO_DMA) && defined(UNSAFE)
	spin_lock_irq(instance->host_lock);
#endif				/* defined(REAL_DMA_POLL) */
	return foo;
#endif				/* def REAL_DMA */
}
#endif				/* defined(REAL_DMA) | defined(PSEUDO_DMA) */

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
 * Purpose : run through the various SCSI phases and do as the target 
 *      directs us to.  Operates on the currently connected command, 
 *      instance->connected.
 *
 * Inputs : instance, instance for which we are doing commands
 *
 * Side effects : SCSI things happen, the disconnected queue will be 
 *      modified if a command disconnects, *instance->connected will
 *      change.
 *
 * XXX Note : we need to watch for bus free or a reset condition here 
 *      to recover from an unexpected bus free condition.
 *
 * Locks: io_request_lock held by caller in IRQ mode
 */

static void NCR5380_information_transfer(struct Scsi_Host *instance) {
	NCR5380_local_declare();
	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
	int transfersize;
#endif
	unsigned char *data;
	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
	Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
	/* RvC: we need to set the end of the polling time */
	unsigned long poll_time = jiffies + USLEEP_POLL;

	NCR5380_setup(instance);

	while (1) {
		tmp = NCR5380_read(STATUS_REG);
		/* We only have a valid SCSI phase when REQ is asserted */
		if (tmp & SR_REQ) {
			phase = (tmp & PHASE_MASK);
			if (phase != old_phase) {
				old_phase = phase;
				NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
			}
			if (sink && (phase != PHASE_MSGOUT)) {
				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
				while (NCR5380_read(STATUS_REG) & SR_REQ);
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
				sink = 0;
				continue;
			}
			switch (phase) {
			case PHASE_DATAIN:
			case PHASE_DATAOUT:
#if (NDEBUG & NDEBUG_NO_DATAOUT)
				printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
				cmd->scsi_done(cmd);
				return;
#endif
				/* 
				 * If there is no room left in the current buffer in the
				 * scatter-gather list, move onto the next one.
				 */

				if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
					++cmd->SCp.buffer;
					--cmd->SCp.buffers_residual;
					cmd->SCp.this_residual = cmd->SCp.buffer->length;
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
					dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
				}
				/*
				 * The preferred transfer method is going to be 
				 * PSEUDO-DMA for systems that are strictly PIO,
				 * since we can let the hardware do the handshaking.
				 *
				 * For this to work, we need to know the transfersize
				 * ahead of time, since the pseudo-DMA code will sit
				 * in an unconditional loop.
				 */

#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
				/* KLL
				 * PSEUDO_DMA is defined here. If this is the g_NCR5380
				 * driver then it will always be defined, so the
				 * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
				 * NCR5380 case.  I think this is a fairly clean solution.
				 * We supplement these 2 if's with the flag.
				 */
#ifdef NCR5380_dma_xfer_len
				if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
#else
				transfersize = cmd->transfersize;

#ifdef LIMIT_TRANSFERSIZE	/* If we have problems with interrupt service */
				if (transfersize > 512)
					transfersize = 512;
#endif				/* LIMIT_TRANSFERSIZE */

				if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
					/* Limit transfers to 32K, for xx400 & xx406
					 * pseudoDMA that transfers in 128 bytes blocks. */
					if (transfersize > 32 * 1024)
						transfersize = 32 * 1024;
#endif
					len = transfersize;
					if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
						/*
						 * If the watchdog timer fires, all future accesses to this
						 * device will use the polled-IO.
						 */
						scmd_printk(KERN_INFO, cmd,
							    "switching to slow handshake\n");
						cmd->device->borken = 1;
						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
						sink = 1;
						do_abort(instance);
						cmd->result = DID_ERROR << 16;
						cmd->scsi_done(cmd);
						/* XXX - need to source or sink data here, as appropriate */
					} else
						cmd->SCp.this_residual -= transfersize - len;
				} else
#endif				/* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
					NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
							     &cmd->SCp.ptr);
				break;
			case PHASE_MSGIN:
				len = 1;
				data = &tmp;
				NCR5380_transfer_pio(instance, &phase, &len, &data);
				cmd->SCp.Message = tmp;

				switch (tmp) {
					/*
					 * Linking lets us reduce the time required to get the 
					 * next command out to the device, hopefully this will
					 * mean we don't waste another revolution due to the delays
					 * required by ARBITRATION and another SELECTION.
					 *
					 * In the current implementation proposal, low level drivers
					 * merely have to start the next command, pointed to by 
					 * next_link, done() is called as with unlinked commands.
					 */
#ifdef LINKED
				case LINKED_CMD_COMPLETE:
				case LINKED_FLG_CMD_COMPLETE:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
					/* 
					 * Sanity check : A linked command should only terminate with
					 * one of these messages if there are more linked commands
					 * available.
					 */
					if (!cmd->next_link) {
						printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
						sink = 1;
						do_abort(instance);
						return;
					}
					initialize_SCp(cmd->next_link);
					/* The next command is still part of this process */
					cmd->next_link->tag = cmd->tag;
					cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
					dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked request done, calling scsi_done().\n", instance->host_no, cmd->device->id, cmd->device->lun));
					collect_stats(hostdata, cmd);
					cmd->scsi_done(cmd);
					cmd = hostdata->connected;
					break;
#endif				/* def LINKED */
				case ABORT:
				case COMMAND_COMPLETE:
					/* Accept message by clearing ACK */
					sink = 1;
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					hostdata->connected = NULL;
					dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);

					/* 
					 * I'm not sure what the correct thing to do here is : 
					 * 
					 * If the command that just executed is NOT a request 
					 * sense, the obvious thing to do is to set the result
					 * code to the values of the stored parameters.
					 * 
					 * If it was a REQUEST SENSE command, we need some way 
					 * to differentiate between the failure code of the original
					 * and the failure code of the REQUEST sense - the obvious
					 * case is success, where we fall through and leave the result
					 * code unchanged.
					 * 
					 * The non-obvious place is where the REQUEST SENSE failed 
					 */

					if (cmd->cmnd[0] != REQUEST_SENSE)
						cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
					else if (status_byte(cmd->SCp.Status) != GOOD)
						cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);

#ifdef AUTOSENSE
					if ((cmd->cmnd[0] == REQUEST_SENSE) &&
						hostdata->ses.cmd_len) {
						scsi_eh_restore_cmnd(cmd, &hostdata->ses);
						hostdata->ses.cmd_len = 0 ;
					}

					if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
						scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);

						dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));

						LIST(cmd, hostdata->issue_queue);
						cmd->host_scribble = (unsigned char *)
						    hostdata->issue_queue;
						hostdata->issue_queue = (Scsi_Cmnd *) cmd;
						dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
					} else
#endif				/* def AUTOSENSE */
					{
						collect_stats(hostdata, cmd);
						cmd->scsi_done(cmd);
					}

					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
					/* 
					 * Restore phase bits to 0 so an interrupted selection, 
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);

					while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
						barrier();
					return;
				case MESSAGE_REJECT:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					switch (hostdata->last_message) {
					case HEAD_OF_QUEUE_TAG:
					case ORDERED_QUEUE_TAG:
					case SIMPLE_QUEUE_TAG:
						cmd->device->simple_tags = 0;
						hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
						break;
					default:
						break;
					}
				case DISCONNECT:{
						/* Accept message by clearing ACK */
						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
						cmd->device->disconnect = 1;
						LIST(cmd, hostdata->disconnected_queue);
						cmd->host_scribble = (unsigned char *)
						    hostdata->disconnected_queue;
						hostdata->connected = NULL;
						hostdata->disconnected_queue = cmd;
						dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d lun %d was moved from connected to" "  the disconnected_queue\n", instance->host_no, cmd->device->id, cmd->device->lun));
						/* 
						 * Restore phase bits to 0 so an interrupted selection, 
						 * arbitration can resume.
						 */
						NCR5380_write(TARGET_COMMAND_REG, 0);

						/* Enable reselect interrupts */
						NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
						/* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
						/* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
						while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
							barrier();
						return;
					}
					/* 
					 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
					 * operation, in violation of the SCSI spec so we can safely 
					 * ignore SAVE/RESTORE pointers calls.
					 *
					 * Unfortunately, some disks violate the SCSI spec and 
					 * don't issue the required SAVE_POINTERS message before
					 * disconnecting, and we have to break spec to remain 
					 * compatible.
					 */
				case SAVE_POINTERS:
				case RESTORE_POINTERS:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					break;
				case EXTENDED_MESSAGE:
/* 
 * Extended messages are sent in the following format :
 * Byte         
 * 0            EXTENDED_MESSAGE == 1
 * 1            length (includes one byte for code, doesn't 
 *              include first two bytes)
 * 2            code
 * 3..length+1  arguments
 *
 * Start the extended message buffer with the EXTENDED_MESSAGE
 * byte, since spi_print_msg() wants the whole thing.  
 */
					extended_msg[0] = EXTENDED_MESSAGE;
					/* Accept first byte by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);

					dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));

					if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
						/* Accept third byte by clearing ACK */
						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
						len = extended_msg[1] - 1;
						data = extended_msg + 3;
						phase = PHASE_MSGIN;

						NCR5380_transfer_pio(instance, &phase, &len, &data);
						dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));

						switch (extended_msg[2]) {
						case EXTENDED_SDTR:
						case EXTENDED_WDTR:
						case EXTENDED_MODIFY_DATA_POINTER:
						case EXTENDED_EXTENDED_IDENTIFY:
							tmp = 0;
						}
					} else if (len) {
						printk("scsi%d: error receiving extended message\n", instance->host_no);
						tmp = 0;
					} else {
						printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
						tmp = 0;
					}
					/* Fall through to reject message */

					/* 
					 * If we get something weird that we aren't expecting, 
					 * reject it.
					 */
				default:
					if (!tmp) {
						printk("scsi%d: rejecting message ", instance->host_no);
						spi_print_msg(extended_msg);
						printk("\n");
					} else if (tmp != EXTENDED_MESSAGE)
						scmd_printk(KERN_INFO, cmd,
							"rejecting unknown message %02x\n",tmp);
					else
						scmd_printk(KERN_INFO, cmd,
							"rejecting unknown extended message code %02x, length %d\n", extended_msg[1], extended_msg[0]);

					msgout = MESSAGE_REJECT;
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
					break;
				}	/* switch (tmp) */
				break;
			case PHASE_MSGOUT:
				len = 1;
				data = &msgout;
				hostdata->last_message = msgout;
				NCR5380_transfer_pio(instance, &phase, &len, &data);
				if (msgout == ABORT) {
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
					hostdata->connected = NULL;
					cmd->result = DID_ERROR << 16;
					collect_stats(hostdata, cmd);
					cmd->scsi_done(cmd);
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
					return;
				}
				msgout = NOP;
				break;
			case PHASE_CMDOUT:
				len = cmd->cmd_len;
				data = cmd->cmnd;
				/* 
				 * XXX for performance reasons, on machines with a 
				 * PSEUDO-DMA architecture we should probably 
				 * use the dma transfer function.  
				 */
				NCR5380_transfer_pio(instance, &phase, &len, &data);
				if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
					NCR5380_set_timer(hostdata, USLEEP_SLEEP);
					dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
					return;
				}
				break;
			case PHASE_STATIN:
				len = 1;
				data = &tmp;
				NCR5380_transfer_pio(instance, &phase, &len, &data);
				cmd->SCp.Status = tmp;
				break;
			default:
				printk("scsi%d : unknown phase\n", instance->host_no);
				NCR5380_dprint(NDEBUG_ALL, instance);
			}	/* switch(phase) */
		}		/* if (tmp * SR_REQ) */
		else {
			/* RvC: go to sleep if polling time expired
			 */
			if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
				NCR5380_set_timer(hostdata, USLEEP_SLEEP);
				dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
				return;
			}
		}
	}			/* while (1) */
}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
 * Purpose : does reselection, initializing the instance->connected 
 *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 
 *      nexus has been reestablished,
 *      
 * Inputs : instance - this instance of the NCR5380.
 *
 * Locks: io_request_lock held by caller if IRQ driven
 */

static void NCR5380_reselect(struct Scsi_Host *instance) {
	NCR5380_local_declare();
	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
	 instance->hostdata;
	unsigned char target_mask;
	unsigned char lun, phase;
	int len;
	unsigned char msg[3];
	unsigned char *data;
	Scsi_Cmnd *tmp = NULL, *prev;
	int abort = 0;
	NCR5380_setup(instance);

	/*
	 * Disable arbitration, etc. since the host adapter obviously
	 * lost, and tell an interrupted NCR5380_select() to restart.
	 */

	NCR5380_write(MODE_REG, MR_BASE);
	hostdata->restart_select = 1;

	target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
	dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));

	/* 
	 * At this point, we have detected that our SCSI ID is on the bus,
	 * SEL is true and BSY was false for at least one bus settle delay
	 * (400 ns).
	 *
	 * We must assert BSY ourselves, until the target drops the SEL
	 * signal.
	 */

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);

	/* FIXME: timeout too long, must fail to workqueue */	
	if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
		abort = 1;
		
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	/*
	 * Wait for target to go into MSGIN.
	 * FIXME: timeout needed and fail to work queeu
	 */

	if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
		abort = 1;

	len = 1;
	data = msg;
	phase = PHASE_MSGIN;
	NCR5380_transfer_pio(instance, &phase, &len, &data);

	if (!(msg[0] & 0x80)) {
		printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
		spi_print_msg(msg);
		abort = 1;
	} else {
		/* Accept message by clearing ACK */
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		lun = (msg[0] & 0x07);

		/* 
		 * We need to add code for SCSI-II to track which devices have
		 * I_T_L_Q nexuses established, and which have simple I_T_L
		 * nexuses so we can chose to do additional data transfer.
		 */

		/* 
		 * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we 
		 * just reestablished, and remove it from the disconnected queue.
		 */


		for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
			if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
			    ) {
				if (prev) {
					REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
					prev->host_scribble = tmp->host_scribble;
				} else {
					REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
					hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
				}
				tmp->host_scribble = NULL;
				break;
			}
		if (!tmp) {
			printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
			/* 
			 * Since we have an established nexus that we can't do anything with,
			 * we must abort it.  
			 */
			abort = 1;
		}
	}

	if (abort) {
		do_abort(instance);
	} else {
		hostdata->connected = tmp;
		dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
	}
}

/*
 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
 *
 * Purpose : called by interrupt handler when DMA finishes or a phase
 *      mismatch occurs (which would finish the DMA transfer).  
 *
 * Inputs : instance - this instance of the NCR5380.
 *
 * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
 *      nexus has been reestablished, on failure NULL is returned.
 */

#ifdef REAL_DMA
static void NCR5380_dma_complete(NCR5380_instance * instance) {
	NCR5380_local_declare();
	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
	int transferred;
	NCR5380_setup(instance);

	/*
	 * XXX this might not be right.
	 *
	 * Wait for final byte to transfer, ie wait for ACK to go false.
	 *
	 * We should use the Last Byte Sent bit, unfortunately this is 
	 * not available on the 5380/5381 (only the various CMOS chips)
	 *
	 * FIXME: timeout, and need to handle long timeout/irq case
	 */

	NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);

	NCR5380_write(MODE_REG, MR_BASE);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	/*
	 * The only places we should see a phase mismatch and have to send
	 * data from the same set of pointers will be the data transfer
	 * phases.  So, residual, requested length are only important here.
	 */

	if (!(hostdata->connected->SCp.phase & SR_CD)) {
		transferred = instance->dmalen - NCR5380_dma_residual();
		hostdata->connected->SCp.this_residual -= transferred;
		hostdata->connected->SCp.ptr += transferred;
	}
}
#endif				/* def REAL_DMA */

/*
 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
 *
 * Purpose : abort a command
 *
 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 
 *      host byte of the result field to, if zero DID_ABORTED is 
 *      used.
 *
 * Returns : 0 - success, -1 on failure.
 *
 *	XXX - there is no way to abort the command that is currently 
 *	connected, you have to wait for it to complete.  If this is 
 *	a problem, we could implement longjmp() / setjmp(), setjmp()
 *	called where the loop started in NCR5380_main().
 *
 * Locks: host lock taken by caller
 */

static int NCR5380_abort(Scsi_Cmnd * cmd) {
	NCR5380_local_declare();
	struct Scsi_Host *instance = cmd->device->host;
	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
	Scsi_Cmnd *tmp, **prev;
	
	printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
	scsi_print_command(cmd);

	NCR5380_print_status(instance);

	NCR5380_setup(instance);

	dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
	dprintk(NDEBUG_ABORT, ("        basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));

#if 0
/*
 * Case 1 : If the command is the currently executing command, 
 * we'll set the aborted flag and return control so that 
 * information transfer routine can exit cleanly.
 */

	if (hostdata->connected == cmd) {
		dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
		hostdata->aborted = 1;
/*
 * We should perform BSY checking, and make sure we haven't slipped
 * into BUS FREE.
 */

		NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
/* 
 * Since we can't change phases until we've completed the current 
 * handshake, we have to source or sink a byte of data if the current
 * phase is not MSGOUT.
 */

/* 
 * Return control to the executing NCR drive so we can clear the
 * aborted flag and get back into our main loop.
 */

		return 0;
	}
#endif

/* 
 * Case 2 : If the command hasn't been issued yet, we simply remove it 
 *          from the issue queue.
 */
 
	dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
	for (prev = (Scsi_Cmnd **) & (hostdata->issue_queue), tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
		if (cmd == tmp) {
			REMOVE(5, *prev, tmp, tmp->host_scribble);
			(*prev) = (Scsi_Cmnd *) tmp->host_scribble;
			tmp->host_scribble = NULL;
			tmp->result = DID_ABORT << 16;
			dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
			tmp->scsi_done(tmp);
			return SUCCESS;
		}
#if (NDEBUG  & NDEBUG_ABORT)
	/* KLL */
		else if (prev == tmp)
			printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
#endif

/* 
 * Case 3 : If any commands are connected, we're going to fail the abort
 *          and let the high level SCSI driver retry at a later time or 
 *          issue a reset.
 *
 *          Timeouts, and therefore aborted commands, will be highly unlikely
 *          and handling them cleanly in this situation would make the common
 *          case of noresets less efficient, and would pollute our code.  So,
 *          we fail.
 */

	if (hostdata->connected) {
		dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
		return FAILED;
	}
/*
 * Case 4: If the command is currently disconnected from the bus, and 
 *      there are no connected commands, we reconnect the I_T_L or 
 *      I_T_L_Q nexus associated with it, go into message out, and send 
 *      an abort message.
 *
 * This case is especially ugly. In order to reestablish the nexus, we
 * need to call NCR5380_select().  The easiest way to implement this 
 * function was to abort if the bus was busy, and let the interrupt
 * handler triggered on the SEL for reselect take care of lost arbitrations
 * where necessary, meaning interrupts need to be enabled.
 *
 * When interrupts are enabled, the queues may change - so we 
 * can't remove it from the disconnected queue before selecting it
 * because that could cause a failure in hashing the nexus if that 
 * device reselected.
 * 
 * Since the queues may change, we can't use the pointers from when we
 * first locate it.
 *
 * So, we must first locate the command, and if NCR5380_select()
 * succeeds, then issue the abort, relocate the command and remove
 * it from the disconnected queue.
 */

	for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
		if (cmd == tmp) {
			dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));

			if (NCR5380_select(instance, cmd, (int) cmd->tag))
				return FAILED;
			dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));

			do_abort(instance);

			for (prev = (Scsi_Cmnd **) & (hostdata->disconnected_queue), tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
				if (cmd == tmp) {
					REMOVE(5, *prev, tmp, tmp->host_scribble);
					*prev = (Scsi_Cmnd *) tmp->host_scribble;
					tmp->host_scribble = NULL;
					tmp->result = DID_ABORT << 16;
					tmp->scsi_done(tmp);
					return SUCCESS;
				}
		}
/*
 * Case 5 : If we reached this point, the command was not found in any of 
 *          the queues.
 *
 * We probably reached this point because of an unlikely race condition
 * between the command completing successfully and the abortion code,
 * so we won't panic, but we will notify the user in case something really
 * broke.
 */
	printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
			"         before abortion\n", instance->host_no);
	return FAILED;
}


/* 
 * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
 * 
 * Purpose : reset the SCSI bus.
 *
 * Returns : SUCCESS
 *
 * Locks: host lock taken by caller
 */

static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
{
	struct Scsi_Host *instance = cmd->device->host;

	NCR5380_local_declare();
	NCR5380_setup(instance);
	NCR5380_print_status(instance);

	spin_lock_irq(instance->host_lock);
	do_reset(instance);
	spin_unlock_irq(instance->host_lock);

	return SUCCESS;
}