wd33c93.c

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/* Make sure that reselection is enabled at this point - it may
 * have been turned off for the command that just completed.
 */

		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
		DB(DB_INTR, printk("DISC-%ld", cmd->serial_number))
		    if (cmd == NULL) {
			printk(" - Already disconnected! ");
			hostdata->state = S_UNCONNECTED;
		}
		switch (hostdata->state) {
		case S_PRE_CMP_DISC:
			hostdata->connected = NULL;
			hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
			hostdata->state = S_UNCONNECTED;
			DB(DB_INTR, printk(":%d", cmd->SCp.Status))
			    if (cmd->cmnd[0] == REQUEST_SENSE
				&& cmd->SCp.Status != GOOD)
				cmd->result =
				    (cmd->
				     result & 0x00ffff) | (DID_ERROR << 16);
			else
				cmd->result =
				    cmd->SCp.Status | (cmd->SCp.Message << 8);
			cmd->scsi_done(cmd);
			break;
		case S_PRE_TMP_DISC:
		case S_RUNNING_LEVEL2:
			cmd->host_scribble = (uchar *) hostdata->disconnected_Q;
			hostdata->disconnected_Q = cmd;
			hostdata->connected = NULL;
			hostdata->state = S_UNCONNECTED;

#ifdef PROC_STATISTICS
			hostdata->disc_done_cnt[cmd->device->id]++;
#endif

			break;
		default:
			printk("*** Unexpected DISCONNECT interrupt! ***");
			hostdata->state = S_UNCONNECTED;
		}

/* We are no longer connected to a target - check to see if
 * there are commands waiting to be executed.
 */
		spin_unlock_irqrestore(&hostdata->lock, flags);
		wd33c93_execute(instance);
		break;

	case CSR_RESEL_AM:
	case CSR_RESEL:
		DB(DB_INTR, printk("RESEL%s", sr == CSR_RESEL_AM ? "_AM" : ""))

		    /* Old chips (pre -A ???) don't have advanced features and will
		     * generate CSR_RESEL.  In that case we have to extract the LUN the
		     * hard way (see below).
		     * First we have to make sure this reselection didn't
		     * happen during Arbitration/Selection of some other device.
		     * If yes, put losing command back on top of input_Q.
		     */
		    if (hostdata->level2 <= L2_NONE) {

			if (hostdata->selecting) {
				cmd = (struct scsi_cmnd *) hostdata->selecting;
				hostdata->selecting = NULL;
				hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
				cmd->host_scribble =
				    (uchar *) hostdata->input_Q;
				hostdata->input_Q = cmd;
			}
		}

		else {

			if (cmd) {
				if (phs == 0x00) {
					hostdata->busy[cmd->device->id] &=
					    ~(1 << cmd->device->lun);
					cmd->host_scribble =
					    (uchar *) hostdata->input_Q;
					hostdata->input_Q = cmd;
				} else {
					printk
					    ("---%02x:%02x:%02x-TROUBLE: Intrusive ReSelect!---",
					     asr, sr, phs);
					while (1)
						printk("\r");
				}
			}

		}

		/* OK - find out which device reselected us. */

		id = read_wd33c93(regs, WD_SOURCE_ID);
		id &= SRCID_MASK;

		/* and extract the lun from the ID message. (Note that we don't
		 * bother to check for a valid message here - I guess this is
		 * not the right way to go, but...)
		 */

		if (sr == CSR_RESEL_AM) {
			lun = read_wd33c93(regs, WD_DATA);
			if (hostdata->level2 < L2_RESELECT)
				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
			lun &= 7;
		} else {
			/* Old chip; wait for msgin phase to pick up the LUN. */
			for (lun = 255; lun; lun--) {
				if ((asr = read_aux_stat(regs)) & ASR_INT)
					break;
				udelay(10);
			}
			if (!(asr & ASR_INT)) {
				printk
				    ("wd33c93: Reselected without IDENTIFY\n");
				lun = 0;
			} else {
				/* Verify this is a change to MSG_IN and read the message */
				sr = read_wd33c93(regs, WD_SCSI_STATUS);
				udelay(7);
				if (sr == (CSR_ABORT | PHS_MESS_IN) ||
				    sr == (CSR_UNEXP | PHS_MESS_IN) ||
				    sr == (CSR_SRV_REQ | PHS_MESS_IN)) {
					/* Got MSG_IN, grab target LUN */
					lun = read_1_byte(regs);
					/* Now we expect a 'paused with ACK asserted' int.. */
					asr = read_aux_stat(regs);
					if (!(asr & ASR_INT)) {
						udelay(10);
						asr = read_aux_stat(regs);
						if (!(asr & ASR_INT))
							printk
							    ("wd33c93: No int after LUN on RESEL (%02x)\n",
							     asr);
					}
					sr = read_wd33c93(regs, WD_SCSI_STATUS);
					udelay(7);
					if (sr != CSR_MSGIN)
						printk
						    ("wd33c93: Not paused with ACK on RESEL (%02x)\n",
						     sr);
					lun &= 7;
					write_wd33c93_cmd(regs,
							  WD_CMD_NEGATE_ACK);
				} else {
					printk
					    ("wd33c93: Not MSG_IN on reselect (%02x)\n",
					     sr);
					lun = 0;
				}
			}
		}

		/* Now we look for the command that's reconnecting. */

		cmd = (struct scsi_cmnd *) hostdata->disconnected_Q;
		patch = NULL;
		while (cmd) {
			if (id == cmd->device->id && lun == cmd->device->lun)
				break;
			patch = cmd;
			cmd = (struct scsi_cmnd *) cmd->host_scribble;
		}

		/* Hmm. Couldn't find a valid command.... What to do? */

		if (!cmd) {
			printk
			    ("---TROUBLE: target %d.%d not in disconnect queue---",
			     id, lun);
			spin_unlock_irqrestore(&hostdata->lock, flags);
			return;
		}

		/* Ok, found the command - now start it up again. */

		if (patch)
			patch->host_scribble = cmd->host_scribble;
		else
			hostdata->disconnected_Q =
			    (struct scsi_cmnd *) cmd->host_scribble;
		hostdata->connected = cmd;

		/* We don't need to worry about 'initialize_SCp()' or 'hostdata->busy[]'
		 * because these things are preserved over a disconnect.
		 * But we DO need to fix the DPD bit so it's correct for this command.
		 */

		if (cmd->sc_data_direction == DMA_TO_DEVICE)
			write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
		else
			write_wd33c93(regs, WD_DESTINATION_ID,
				      cmd->device->id | DSTID_DPD);
		if (hostdata->level2 >= L2_RESELECT) {
			write_wd33c93_count(regs, 0);	/* we want a DATA_PHASE interrupt */
			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
			hostdata->state = S_RUNNING_LEVEL2;
		} else
			hostdata->state = S_CONNECTED;

		DB(DB_INTR, printk("-%ld", cmd->serial_number))
		    spin_unlock_irqrestore(&hostdata->lock, flags);
		break;

	default:
		printk("--UNKNOWN INTERRUPT:%02x:%02x:%02x--", asr, sr, phs);
		spin_unlock_irqrestore(&hostdata->lock, flags);
	}

	DB(DB_INTR, printk("} "))

}

static void
reset_wd33c93(struct Scsi_Host *instance)
{
	struct WD33C93_hostdata *hostdata =
	    (struct WD33C93_hostdata *) instance->hostdata;
	const wd33c93_regs regs = hostdata->regs;
	uchar sr;

#ifdef CONFIG_SGI_IP22
	{
		int busycount = 0;
		extern void sgiwd93_reset(unsigned long);
		/* wait 'til the chip gets some time for us */
		while ((read_aux_stat(regs) & ASR_BSY) && busycount++ < 100)
			udelay (10);
	/*
 	 * there are scsi devices out there, which manage to lock up
	 * the wd33c93 in a busy condition. In this state it won't
	 * accept the reset command. The only way to solve this is to
 	 * give the chip a hardware reset (if possible). The code below
	 * does this for the SGI Indy, where this is possible
	 */
	/* still busy ? */
	if (read_aux_stat(regs) & ASR_BSY)
		sgiwd93_reset(instance->base); /* yeah, give it the hard one */
	}
#endif

	write_wd33c93(regs, WD_OWN_ID, OWNID_EAF | OWNID_RAF |
		      instance->this_id | hostdata->clock_freq);
	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
		      calc_sync_xfer(hostdata->default_sx_per / 4,
				     DEFAULT_SX_OFF, 0, hostdata->sx_table));
	write_wd33c93(regs, WD_COMMAND, WD_CMD_RESET);


#ifdef CONFIG_MVME147_SCSI
	udelay(25);		/* The old wd33c93 on MVME147 needs this, at least */
#endif

	while (!(read_aux_stat(regs) & ASR_INT))
		;
	sr = read_wd33c93(regs, WD_SCSI_STATUS);

	hostdata->microcode = read_wd33c93(regs, WD_CDB_1);
	if (sr == 0x00)
		hostdata->chip = C_WD33C93;
	else if (sr == 0x01) {
		write_wd33c93(regs, WD_QUEUE_TAG, 0xa5);	/* any random number */
		sr = read_wd33c93(regs, WD_QUEUE_TAG);
		if (sr == 0xa5) {
			hostdata->chip = C_WD33C93B;
			write_wd33c93(regs, WD_QUEUE_TAG, 0);
		} else
			hostdata->chip = C_WD33C93A;
	} else
		hostdata->chip = C_UNKNOWN_CHIP;

	if (hostdata->chip != C_WD33C93B)	/* Fast SCSI unavailable */
		hostdata->fast = 0;

	write_wd33c93(regs, WD_TIMEOUT_PERIOD, TIMEOUT_PERIOD_VALUE);
	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
}

int
wd33c93_host_reset(struct scsi_cmnd * SCpnt)
{
	struct Scsi_Host *instance;
	struct WD33C93_hostdata *hostdata;
	int i;

	instance = SCpnt->device->host;
	hostdata = (struct WD33C93_hostdata *) instance->hostdata;

	printk("scsi%d: reset. ", instance->host_no);
	disable_irq(instance->irq);

	hostdata->dma_stop(instance, NULL, 0);
	for (i = 0; i < 8; i++) {
		hostdata->busy[i] = 0;
		hostdata->sync_xfer[i] =
			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
					0, hostdata->sx_table);
		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
	}
	hostdata->input_Q = NULL;
	hostdata->selecting = NULL;
	hostdata->connected = NULL;
	hostdata->disconnected_Q = NULL;
	hostdata->state = S_UNCONNECTED;
	hostdata->dma = D_DMA_OFF;
	hostdata->incoming_ptr = 0;
	hostdata->outgoing_len = 0;

	reset_wd33c93(instance);
	SCpnt->result = DID_RESET << 16;
	enable_irq(instance->irq);
	return SUCCESS;
}

int
wd33c93_abort(struct scsi_cmnd * cmd)
{
	struct Scsi_Host *instance;
	struct WD33C93_hostdata *hostdata;
	wd33c93_regs regs;
	struct scsi_cmnd *tmp, *prev;

	disable_irq(cmd->device->host->irq);

	instance = cmd->device->host;
	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
	regs = hostdata->regs;

/*
 * Case 1 : If the command hasn't been issued yet, we simply remove it
 *     from the input_Q.
 */

	tmp = (struct scsi_cmnd *) hostdata->input_Q;
	prev = NULL;
	while (tmp) {
		if (tmp == cmd) {
			if (prev)
				prev->host_scribble = cmd->host_scribble;
			else
				hostdata->input_Q =
				    (struct scsi_cmnd *) cmd->host_scribble;
			cmd->host_scribble = NULL;
			cmd->result = DID_ABORT << 16;
			printk
			    ("scsi%d: Abort - removing command %ld from input_Q. ",
			     instance->host_no, cmd->serial_number);
			enable_irq(cmd->device->host->irq);
			cmd->scsi_done(cmd);
			return SUCCESS;
		}
		prev = tmp;
		tmp = (struct scsi_cmnd *) tmp->host_scribble;
	}

/*
 * Case 2 : If the command is 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 == cmd) {
		uchar sr, asr;
		unsigned long timeout;

		printk("scsi%d: Aborting connected command %ld - ",
		       instance->host_no, cmd->serial_number);

		printk("stopping DMA - ");
		if (hostdata->dma == D_DMA_RUNNING) {
			hostdata->dma_stop(instance, cmd, 0);
			hostdata->dma = D_DMA_OFF;
		}

		printk("sending wd33c93 ABORT command - ");
		write_wd33c93(regs, WD_CONTROL,
			      CTRL_IDI | CTRL_EDI | CTRL_POLLED);
		write_wd33c93_cmd(regs, WD_CMD_ABORT);

/* Now we have to attempt to flush out the FIFO... */

		printk("flushing fifo - ");
		timeout = 1000000;
		do {
			asr = read_aux_stat(regs);
			if (asr & ASR_DBR)
				read_wd33c93(regs, WD_DATA);
		} while (!(asr & ASR_INT) && timeout-- > 0);
		sr = read_wd33c93(regs, WD_SCSI_STATUS);
		printk
		    ("asr=%02x, sr=%02x, %ld bytes un-transferred (timeout=%ld) - ",
		     asr, sr, read_wd33c93_count(regs), timeout);

		/*
		 * Abort command processed.
		 * Still connected.
		 * We must disconnect.
		 */

		printk("sending wd33c93 DISCONNECT command - ");
		write_wd33c93_cmd(regs, WD_CMD_DISCONNECT);

		timeout = 1000000;
		asr = read_aux_stat(regs);
		while ((asr & ASR_CIP) && timeout-- > 0)
			asr = read_aux_stat(regs);
		sr = read_wd33c93(regs, WD_SCSI_STATUS);
		printk("asr=%02x, sr=%02x.", asr, sr);

		hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
		hostdata->connected = NULL;
		hostdata->state = S_UNCONNECTED;
		cmd->result = DID_ABORT << 16;

/*      sti();*/
		wd33c93_execute(instance);

		enable_irq(cmd->device->host->irq);
		cmd->scsi_done(cmd);