ATAPI Tape drive support. Should be considered experimental.

Major restructuring of the code path that sends ATAPI packet commands.
One set of functions works in polling, process, and interrupt contexts.

2 files changed, 559 insertions, 368 deletions

diff --git a/sys/dev/atapiscsi/atapiscsi.c b/sys/dev/atapiscsi/atapiscsi.c
index 5938166e8ee..98d2816ce1e 100644
--- a/sys/dev/atapiscsi/atapiscsi.c
+++ b/sys/dev/atapiscsi/atapiscsi.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: atapiscsi.c,v 1.19 1999/11/17 01:22:55 csapuntz Exp $     */
+/*      $OpenBSD: atapiscsi.c,v 1.20 1999/12/11 10:15:02 csapuntz Exp $     */
 
 /*
  * This code is derived from code with the copyright below.
@@ -77,6 +77,7 @@
 #define DEBUG_POLL   0x40
 #define DEBUG_ERRORS 0x80   /* Debug error handling code */
 
+#define WDCDEBUG
 #ifdef WDCDEBUG
 int wdcdebug_atapi_mask = 0;
 #define WDCDEBUG_PRINT(args, level) \
@@ -89,18 +90,46 @@ int wdcdebug_atapi_mask = 0;
 /* 10 ms, this is used only before sending a cmd.  */
 #define ATAPI_DELAY 10
 #define ATAPI_RESET_WAIT 2000
+#define ATAPI_CTRL_WAIT 4000
 
 /* When polling, let the exponential backoff max out at 1 second's interval. */
 #define ATAPI_POLL_MAXTIC (hz)
 
 void  wdc_atapi_minphys __P((struct buf *bp));
 void  wdc_atapi_start __P((struct channel_softc *,struct wdc_xfer *));
-int   wdc_atapi_intr __P((struct channel_softc *, struct wdc_xfer *, int));
+
+void  timer_handler __P((void *));
+
+int   wdc_atapi_real_start __P((struct channel_softc *, struct wdc_xfer *,
+    int));
+int   wdc_atapi_real_start_2 __P((struct channel_softc *, struct wdc_xfer *,
+    int));
+int   wdc_atapi_intr_command __P((struct channel_softc *, struct wdc_xfer *,
+    int));
+
+int   wdc_atapi_intr_data __P((struct channel_softc *, struct wdc_xfer *,
+    int));
+int   wdc_atapi_intr_complete __P((struct channel_softc *, struct wdc_xfer *,
+    int));
+
+int   wdc_atapi_intr_for_us __P((struct channel_softc *, struct wdc_xfer *,
+    int));
+
+int   wdc_atapi_send_packet __P((struct channel_softc *, struct wdc_xfer *,
+    int));
+int   wdc_atapi_dma_flags __P((struct wdc_xfer *));
+
 int   wdc_atapi_ctrl __P((struct channel_softc *, struct wdc_xfer *, int));
-void  wdc_atapi_done __P((struct channel_softc *, struct wdc_xfer *));
-void  wdc_atapi_reset __P((struct channel_softc *, struct wdc_xfer *));
+int   wdc_atapi_in_data_phase __P((struct wdc_xfer *, int, int));
+
+int   wdc_atapi_intr __P((struct channel_softc *, struct wdc_xfer *, int));
+
+int   wdc_atapi_done __P((struct channel_softc *, struct wdc_xfer *, int));
+int   wdc_atapi_reset __P((struct channel_softc *, struct wdc_xfer *, int));
+int   wdc_atapi_reset_2 __P((struct channel_softc *, struct wdc_xfer *, int));
 int   wdc_atapi_send_cmd __P((struct scsi_xfer *sc_xfer));
 
+int   wdc_atapi_tape_done __P((struct channel_softc *, struct wdc_xfer *, int));
 #define MAX_SIZE MAXPHYS
 
 struct atapiscsi_softc;
@@ -113,6 +142,7 @@ int	wdc_atapi_get_params __P((struct channel_softc *, u_int8_t, struct ataparams
 
 int	atapi_dsc_wait __P((struct ata_drive_datas *, int));
 int	atapi_dsc_ready __P((void *));
+void    atapi_dsc_check __P((void *));
 int	atapi_dsc_semiready __P((void *));
 int	atapi_poll_wait __P((int (*) __P((void *)), void *, int, int, char *));
 void    atapi_to_scsi_sense __P((struct scsi_xfer *, u_int8_t));
@@ -359,11 +389,7 @@ wdc_atapi_send_cmd(sc_xfer)
 	struct ata_drive_datas *drvp = &chp->ch_drive[drive];
 	struct wdc_xfer *xfer;
 	int flags = sc_xfer->flags;
-	int s, ret, saved_datalen;
-	char saved_len_bytes[3];
-
-restart:
-	saved_datalen = 0;
+	int s, ret;
 
 	WDCDEBUG_PRINT(("wdc_atapi_send_cmd %s:%d:%d\n",
 	    chp->wdc->sc_dev.dv_xname, chp->channel, drive), DEBUG_XFERS);
@@ -392,31 +418,32 @@ restart:
 	if (drvp->atapi_cap & ACAP_DSC) {
 		WDCDEBUG_PRINT(("about to send cmd %x ", sc_xfer->cmd->opcode),
 		    DEBUG_DSC);
-		xfer->c_flags |= C_NEEDDONE;
 		switch (sc_xfer->cmd->opcode) {
 		case READ:
 		case WRITE:
+			xfer->c_flags |= C_MEDIA_ACCESS;
+
 			/* If we are not in buffer availability mode,
 			   we limit the first request to 0 bytes, which
 			   gets us into buffer availability mode without
 			   holding the bus.  */
 			if (!(drvp->drive_flags & DRIVE_DSCBA)) {
-				saved_datalen = sc_xfer->datalen;
-				xfer->c_flags &= ~C_NEEDDONE;
-				sc_xfer->datalen = xfer->c_bcount = 0;
-				bcopy(
-				    ((struct scsi_rw_tape *)sc_xfer->cmd)->len,
-				    saved_len_bytes, 3);
+				xfer->c_bcount = 0;
+				xfer->transfer_len = 
+				  _3btol(((struct scsi_rw_tape *)
+					  sc_xfer->cmd)->len);
 				_lto3b(0,
 				    ((struct scsi_rw_tape *)
 				    sc_xfer->cmd)->len);
+				xfer->c_done = wdc_atapi_tape_done;
 				WDCDEBUG_PRINT(
 				    ("R/W in completion mode, do 0 blocks\n"),
 				    DEBUG_DSC);
 			} else
 				WDCDEBUG_PRINT(("R/W %d blocks %d bytes\n",
-				    _3btol(((struct scsi_rw_tape *)
-				    sc_xfer->cmd)->len), sc_xfer->datalen),
+				    _3btol(((struct scsi_rw_tape *)	
+					sc_xfer->cmd)->len), 
+				    sc_xfer->datalen),
 				    DEBUG_DSC);
 
 			/* DSC will change to buffer availability mode.
@@ -427,15 +454,13 @@ restart:
 		case LOAD:
 		case REWIND:
 		case SPACE:
+		case WRITE_FILEMARKS:
 #if 0
 		case LOCATE:
 		case READ_POSITION:
-		case WRITE_FILEMARK:
 #endif
-			/* DSC will change to command completion mode.
-			   We can reflect this early.  */
-			drvp->drive_flags &= ~DRIVE_DSCBA;
-			WDCDEBUG_PRINT(("clear DCSBA\n"), DEBUG_DSC);
+
+			xfer->c_flags |= C_MEDIA_ACCESS;
 			break;
 
 		default:
@@ -445,19 +470,10 @@ restart:
 
 	wdc_exec_xfer(chp, xfer);
 #ifdef DIAGNOSTIC
-	if (((sc_xfer->flags & SCSI_POLL) != 0 ||
-	     (drvp->atapi_cap & ACAP_DSC) != 0) &&
+	if ((xfer->c_flags & C_POLL) != 0 &&
 	    (sc_xfer->flags & ITSDONE) == 0)
 		panic("wdc_atapi_send_cmd: polled command not done");
 #endif
-	if ((drvp->atapi_cap & ACAP_DSC) && saved_datalen != 0) {
-		sc_xfer->datalen = saved_datalen;
-		bcopy(saved_len_bytes,
-		    ((struct scsi_rw_tape *)sc_xfer->cmd)->len, 3);
-		sc_xfer->flags &= ~ITSDONE;
-		splx(s);
-		goto restart;
-	}
 	ret = (sc_xfer->flags & ITSDONE) ? COMPLETE : SUCCESSFULLY_QUEUED;
 	splx(s);
 	return (ret);
@@ -500,14 +516,215 @@ atapi_to_scsi_sense(xfer, flags)
 }
 
 
+enum atapi_context {
+	ctxt_process = 0,
+	ctxt_timer = 1,
+	ctxt_interrupt = 2
+};
+
+int wdc_atapi_the_machine __P((struct channel_softc *, struct wdc_xfer *,
+    enum atapi_context));
+
+int wdc_atapi_the_poll_machine __P((struct channel_softc *, struct wdc_xfer *));
+
 void
 wdc_atapi_start(chp, xfer)
 	struct channel_softc *chp;
 	struct wdc_xfer *xfer;
 {
+	xfer->next = wdc_atapi_real_start;
+
+	wdc_atapi_the_machine(chp, xfer, ctxt_process);
+}
+
+
+void
+timer_handler(arg)
+	void *arg;
+{
+	struct wdc_xfer *xfer = arg;
+	struct channel_softc *chp = xfer->chp;
+	int s;
+
+	xfer->c_flags &= ~C_POLL_MACHINE;
+
+	/* There is a race here between us and the interrupt */
+	s = splbio();
+	wdc_atapi_the_machine(chp, xfer, ctxt_timer);
+	splx(s);
+}
+
+
+int
+wdc_atapi_intr(chp, xfer, irq)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int irq;
+{
+	/* XXX we should consider an alternate signaling regime here */
+	if (xfer->c_flags & C_TIMEOU) {
+		xfer->c_flags &= ~C_TIMEOU;
+		return (wdc_atapi_the_machine(chp, xfer, ctxt_timer));
+	}
+
+	return (wdc_atapi_the_machine(chp, xfer, ctxt_interrupt));
+}
+
+#define CONTINUE_POLL 0
+#define GOTO_NEXT 1
+#define DONE 2
+
+int
+wdc_atapi_the_poll_machine(chp, xfer)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;	
+{
+	int  idx = 0, ret;
+	int  current_timeout;
+
+	xfer->timeout = -1;
+
+	while (1) {
+		idx++;
+
+		xfer->timeout = -1;
+		xfer->delay = 0;
+		xfer->expect_irq = 0;
+
+		ret = (xfer->next)(chp, xfer, (current_timeout * 1000 <= idx));
+
+		if (xfer->timeout != -1) {
+			current_timeout = xfer->timeout;
+			idx = 0;
+		}
+
+		if (xfer->delay != 0) {
+			while (xfer->delay--)
+				delay(1000);
+		}
+
+		switch (ret) {
+		case GOTO_NEXT:
+			break;
+			
+	        case CONTINUE_POLL:
+			DELAY(1);
+
+			break;
+
+		case DONE:
+			wdc_free_xfer(chp, xfer);
+			wdcstart(chp);
+			return (0);
+		}
+	}
+}
+
+int
+wdc_atapi_the_machine(chp, xfer, ctxt)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;	
+	enum atapi_context ctxt;
+{
+	int idx = 0, ret;
+	int claim_irq = 0;
+	u_int64_t now = (u_int64_t)time.tv_sec * 1000 + time.tv_usec / 1000;
+	int timeout_delay = hz / 10;
+
+	if (xfer->c_flags & C_POLL) {
+		if (ctxt != ctxt_process) 
+			return (0);
+
+		wdc_atapi_the_poll_machine(chp, xfer);
+		return (0);
+	}
+
+ do_op:
+	idx++;
+
+	xfer->timeout = -1;
+	xfer->claim_irq = 0;
+	xfer->delay = 0;
+
+	ret = (xfer->next)(chp, xfer, now >= xfer->endtime);
+
+	if (xfer->timeout != -1) {
+		now = (u_int64_t)time.tv_sec * 1000 + 
+		    time.tv_usec / 1000;
+
+		xfer->endtime = (u_int64_t)xfer->timeout + now;
+
+	}
+
+	if (xfer->claim_irq) claim_irq = xfer->claim_irq;
+
+	if (xfer->delay) timeout_delay = max(xfer->delay * hz / 1000, 1);
+
+	switch (ret) {
+	case GOTO_NEXT:
+		if (xfer->expect_irq) {
+			chp->ch_flags |= WDCF_IRQ_WAIT;
+			xfer->expect_irq = 0;
+			timeout(wdctimeout, chp, 
+			    (xfer->endtime - now) * hz / 1000);
+
+			return (claim_irq);
+		}
+
+		if (xfer->delay)
+			break;
+
+		goto do_op;
+
+	case CONTINUE_POLL:
+		if (xfer->delay) break;
+		if (idx >= 50) break;
+
+		DELAY(1);
+		goto do_op;
+
+	case DONE:
+		if (xfer->c_flags & C_POLL_MACHINE)
+			untimeout (timer_handler, xfer);
+
+		wdc_free_xfer(chp, xfer);
+		wdcstart(chp);
+
+		return (claim_irq);
+	}
+
+	timeout(timer_handler, xfer, timeout_delay);
+	xfer->c_flags |= C_POLL_MACHINE;
+	return (claim_irq);
+}
+
+
+void wdc_atapi_update_status __P((struct channel_softc *));
+
+void
+wdc_atapi_update_status(chp)
+	struct channel_softc *chp;
+{
+	chp->ch_status = CHP_READ_REG(chp, wdr_status);
+
+	if (chp->ch_status == 0xff && (chp->ch_flags & WDCF_ONESLAVE)) {
+		CHP_WRITE_REG(chp, wdr_sdh, WDSD_IBM | 0x10);
+
+		chp->ch_status = CHP_READ_REG(chp, wdr_status);
+	}
+
+	if ((chp->ch_status & (WDCS_BSY | WDCS_ERR)) == WDCS_ERR)
+		chp->ch_error = CHP_READ_REG(chp, wdr_error);
+}
+
+int
+wdc_atapi_real_start(chp, xfer, timeout)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int timeout;
+{
 	struct scsi_xfer *sc_xfer = xfer->cmd;
 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
-	struct atapiscsi_softc *as = sc_xfer->sc_link->adapter_softc;
 
 	WDCDEBUG_PRINT(("wdc_atapi_start %s:%d:%d, scsi flags 0x%x\n",
 	    chp->wdc->sc_dev.dv_xname, chp->channel, drvp->drive,
@@ -515,17 +732,44 @@ wdc_atapi_start(chp, xfer)
 	/* Adjust C_DMA, it may have changed if we are requesting sense */
 	if (!(xfer->c_flags & C_POLL) && 
 	    (drvp->drive_flags & (DRIVE_DMA | DRIVE_UDMA)) &&
-	    (sc_xfer->datalen > 0 || (xfer->c_flags & C_SENSE)))
+	    (xfer->c_bcount > 0 || (xfer->c_flags & C_SENSE)))
 		xfer->c_flags |= C_DMA;
 	else
 		xfer->c_flags &= ~C_DMA;
 
-	if (wdc_select_drive(chp, xfer->drive, ATAPI_DELAY) < 0) {
+
+	CHP_WRITE_REG(chp, wdr_sdh, WDSD_IBM | (xfer->drive << 4));
+
+	DELAY(1);
+
+	xfer->next = wdc_atapi_real_start_2;
+	xfer->timeout = ATAPI_DELAY;
+
+	return (GOTO_NEXT);
+}
+
+
+int
+wdc_atapi_real_start_2(chp, xfer, timeout)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int timeout;
+{
+	struct scsi_xfer *sc_xfer = xfer->cmd;
+	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
+
+	if (timeout) {
 		printf("wdc_atapi_start: not ready, st = %02x\n",
 		    chp->ch_status);
+
 		sc_xfer->error = XS_TIMEOUT;
-		wdc_atapi_reset(chp, xfer);
-		return;
+		xfer->next = wdc_atapi_reset;
+		return (GOTO_NEXT);
+	} else {
+		wdc_atapi_update_status(chp);
+		
+		if (chp->ch_status & WDCS_BSY)
+			return (CONTINUE_POLL);
 	}
     
 	/* Do control operations specially. */
@@ -536,22 +780,26 @@ wdc_atapi_start(chp, xfer)
 			    xfer->drive, drvp->state);
 			panic("wdc_atapi_start: bad state");
 		}
-		wdc_atapi_ctrl(chp, xfer, 0);
-		return;
-	}
-	
-	if (drvp->atapi_cap & ACAP_DSC) {
-		if (atapi_dsc_wait(drvp, sc_xfer->timeout)) {
-			sc_xfer->error = XS_TIMEOUT;
-			wdc_atapi_reset(chp, xfer);
-			return;
-		}
-		WDCDEBUG_PRINT(("wdc_atapi_start %s:%d:%d, DSC asserted\n",
-		    chp->wdc->sc_dev.dv_xname, chp->channel, drvp->drive),
-		    DEBUG_DSC);
-		drvp->drive_flags &= ~DRIVE_DSCWAIT;
+
+		xfer->next = wdc_atapi_ctrl;
+		return (GOTO_NEXT);
 	}
 
+	xfer->next = wdc_atapi_send_packet;
+	return (GOTO_NEXT);
+}
+
+
+int
+wdc_atapi_send_packet(chp, xfer, timeout)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int timeout;
+{
+	struct scsi_xfer *sc_xfer = xfer->cmd;
+	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
+	struct atapiscsi_softc *as = sc_xfer->sc_link->adapter_softc;
+
 	/*
 	 * Even with WDCS_ERR, the device should accept a command packet
 	 * Limit length to what can be stuffed into the cylinder register
@@ -569,69 +817,37 @@ wdc_atapi_start(chp, xfer)
 	as->protocol_phase = as_cmdout;
 	as->retries = 0;
 
-	/*
-	 * If there is no interrupt for CMD input, busy-wait for it (done in 
-	 * the interrupt routine. If it is a polled command, call the interrupt
-	 * routine until command is done.
-	 */
-	if (((drvp->atapi_cap & ATAPI_CFG_DRQ_MASK) != ATAPI_CFG_IRQ_DRQ) ||
-	    (sc_xfer->flags & SCSI_POLL) || (drvp->atapi_cap & ACAP_DSC)) {
-		/* Wait for at last 400ns for status bit to be valid */
-		DELAY(1);
-		wdc_atapi_intr(chp, xfer, 0);
-	} else {
-		chp->ch_flags |= WDCF_IRQ_WAIT;
-		timeout(wdctimeout, chp, hz);
-		return;
-	}
+	DELAY(1);
 
-	if ((sc_xfer->flags & SCSI_POLL) || (drvp->atapi_cap & ACAP_DSC)) {
-		while ((sc_xfer->flags & ITSDONE) == 0) {
-			if (drvp->atapi_cap & ACAP_DSC) {
-				if (atapi_poll_wait(
-					(drvp->drive_flags & DRIVE_DSCWAIT) ?
-					    atapi_dsc_ready : atapi_dsc_semiready,
-					    drvp, sc_xfer->timeout, PZERO + PCATCH,
-					    "atapist")) {
-					sc_xfer->error = XS_TIMEOUT;
-					wdc_atapi_reset(chp, xfer);
-					return;
-				}
-			} else
-				/* Wait for at last 400ns for status bit to
-				   be valid */
-				DELAY(1);
+	xfer->next = wdc_atapi_intr_for_us;
+	xfer->timeout = sc_xfer->timeout;
 
-			wdc_atapi_intr(chp, xfer, 0);
-		}
+	if ((drvp->atapi_cap & ATAPI_CFG_DRQ_MASK) == ATAPI_CFG_IRQ_DRQ) {
+		/* We expect an IRQ to tell us of the next state */
+		xfer->expect_irq = 1;
 	}
+	return (GOTO_NEXT);
 }
 
 int
-atapi_dsc_semiready(arg)
-	void *arg;
+wdc_atapi_dma_flags(xfer)
+	struct wdc_xfer *xfer;
 {
-	struct ata_drive_datas *drvp = arg;
-	struct channel_softc *chp = drvp->chnl_softc;
+	struct scsi_xfer *sc_xfer = xfer->cmd;
+	int dma_flags;
 
-	/* We should really wait_for_unbusy here too before 
-	   switching drives. */
-	CHP_WRITE_REG(chp, wdr_sdh, WDSD_IBM | (drvp->drive << 4));
+	dma_flags = ((sc_xfer->flags & SCSI_DATA_IN) ||
+	    (xfer->c_flags & C_SENSE)) ?  WDC_DMA_READ : 0;
+	dma_flags |= (xfer->c_flags & C_POLL) ? WDC_DMA_POLL : 0;
 
-	return (wait_for_unbusy(chp, 0) == 0);
+	return (dma_flags);
 }
 
-
-int wdc_atapi_intr_command __P((struct channel_softc *, struct wdc_xfer *, int));
-int wdc_atapi_intr_data __P((struct channel_softc *, struct wdc_xfer *, int));
-int wdc_atapi_intr_complete __P((struct channel_softc *, struct wdc_xfer *, int));
-
-
 int
-wdc_atapi_intr_command(chp, xfer, dma_flags)
+wdc_atapi_intr_command(chp, xfer, timeout)
 	struct channel_softc *chp;
 	struct wdc_xfer *xfer;
-	int dma_flags;
+	int timeout;
 {
 	struct scsi_xfer *sc_xfer = xfer->cmd;
 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
@@ -640,6 +856,10 @@ wdc_atapi_intr_command(chp, xfer, dma_flags)
 	u_int8_t cmd[16];
 	struct scsi_sense *cmd_reqsense;
 	int cmdlen = (drvp->atapi_cap & ACAP_LEN) ? 16 : 12;
+	int  dma_flags;
+
+	xfer->claim_irq = 1;
+	dma_flags = wdc_atapi_dma_flags(xfer);
 
 	bzero(cmd, sizeof(cmd));
 
@@ -660,8 +880,9 @@ wdc_atapi_intr_command(chp, xfer, dma_flags)
 		    chp->channel, xfer->drive, xfer->databuf, 
 		    xfer->c_bcount, dma_flags) != 0) {
 			sc_xfer->error = XS_DRIVER_STUFFUP;
-			wdc_atapi_done(chp, xfer);
-			return (1);
+
+			xfer->next = wdc_atapi_done;
+			return (GOTO_NEXT);
 		}
 	}
 
@@ -676,57 +897,38 @@ wdc_atapi_intr_command(chp, xfer, dma_flags)
 		    dma_flags);
 	}
 
-	if ((sc_xfer->flags & SCSI_POLL) == 0 &&
-	    (drvp->atapi_cap & ACAP_DSC) == 0) {
-		chp->ch_flags |= WDCF_IRQ_WAIT;
-		timeout(wdctimeout, chp, sc_xfer->timeout * hz / 1000);
-	}
+	xfer->expect_irq = 1;
 
 	/* If we read/write to a tape we will get into buffer
 	   availability mode.  */
 	if (drvp->atapi_cap & ACAP_DSC) {
-		if (!(drvp->drive_flags & DRIVE_DSCBA) &&
-		    (sc_xfer->cmd->opcode == READ ||
-			sc_xfer->cmd->opcode == WRITE)) {
+		if ((sc_xfer->cmd->opcode == READ ||
+		       sc_xfer->cmd->opcode == WRITE)) {
 			drvp->drive_flags |= DRIVE_DSCBA;
 			WDCDEBUG_PRINT(("set DSCBA\n"), DEBUG_DSC);
+		} else if ((xfer->c_flags & C_MEDIA_ACCESS) &&
+		    (drvp->drive_flags & DRIVE_DSCBA)) {
+			/* Clause 3.2.4 of QIC-157 D.
+
+			   Any media access command other than read or
+			   write will switch DSC back to completion
+			   mode */
+			drvp->drive_flags &= ~DRIVE_DSCBA;
+			WDCDEBUG_PRINT(("clear DCSBA\n"), DEBUG_DSC);
 		}
-		if (sc_xfer->cmd->opcode == READ)
-			drvp->drive_flags |= DRIVE_DSCWAIT;
 	}
-	return (1);
 
+	return (GOTO_NEXT);
 }
 
+
 int
-wdc_atapi_intr_data(chp, xfer, dma_flags)
-	struct channel_softc *chp;
+wdc_atapi_in_data_phase(xfer, len, ire)
 	struct wdc_xfer *xfer;
-	int dma_flags;
-
+	int len, ire;
 {
 	struct scsi_xfer *sc_xfer = xfer->cmd;
-	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
-	struct atapiscsi_softc *as = sc_xfer->sc_link->adapter_softc;
-	int len, ire;
-	char *message = 0;
-
-	len = (CHP_READ_REG(chp, wdr_cyl_hi) << 8) |
-	    CHP_READ_REG(chp, wdr_cyl_lo);
-	ire = CHP_READ_REG(chp, wdr_ireason);
-
-	WDCDEBUG_PRINT(("wdc_atapi_intr: c_bcount %d len %d st 0x%x err 0x%x "
-	    "ire 0x%x :", xfer->c_bcount,
-	    len, chp->ch_status, chp->ch_error, ire), DEBUG_INTR);
-
-	/* Possibility to explore; what if we get an interrupt
-	   during DMA ? */
-	if ((xfer->c_flags & C_DMA) != 0) {
-		if ((xfer->c_flags & C_TIMEOU) == 0)
-			message = "unexpected interrupt during DMA mode";
-
-		goto unexpected_state;
-	}
+	char *message;
 
 	if (ire & WDCI_CMD) {
 		message = "unexpectedly in command phase";
@@ -738,7 +940,7 @@ wdc_atapi_intr_data(chp, xfer, dma_flags)
 			message = "data phase where none expected";
 			goto unexpected_state;
 		}
-	
+		
 		/* Make sure polarities match */
 		if (((ire & WDCI_IN) == WDCI_IN) ==
 		    ((sc_xfer->flags & SCSI_DATA_OUT) == SCSI_DATA_OUT)) {
@@ -757,7 +959,36 @@ wdc_atapi_intr_data(chp, xfer, dma_flags)
 		goto unexpected_state;
 	}
 
+
+	return (1);
+
+ unexpected_state:
+
+	return (0);
+}
+
+int
+wdc_atapi_intr_data(chp, xfer, timeout)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int timeout;
+{
+	struct scsi_xfer *sc_xfer = xfer->cmd;
+	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
+	int len, ire;
+
+	len = (CHP_READ_REG(chp, wdr_cyl_hi) << 8) |
+	    CHP_READ_REG(chp, wdr_cyl_lo);
+	ire = CHP_READ_REG(chp, wdr_ireason);
+
+	if (!wdc_atapi_in_data_phase(xfer, len, ire))
+		return (CONTINUE_POLL);
+	
 	if (xfer->c_bcount >= len) {
+	  WDCDEBUG_PRINT(("wdc_atapi_intr: c_bcount %d len %d st 0x%x err 0x%x "
+			  "ire 0x%x\n", xfer->c_bcount,
+			  len, chp->ch_status, chp->ch_error, ire), DEBUG_INTR);
+
 		/* Common case */
 		if (sc_xfer->flags & SCSI_DATA_OUT)
 			wdc_output_bytes(drvp, (u_int8_t *)xfer->databuf +
@@ -793,60 +1024,25 @@ wdc_atapi_intr_data(chp, xfer, dma_flags)
 		xfer->c_bcount = 0;
 	}
 
-	if ((sc_xfer->flags & SCSI_POLL) == 0 &&
-	    (drvp->atapi_cap & ACAP_DSC) == 0) {
-		chp->ch_flags |= WDCF_IRQ_WAIT;
-		timeout(wdctimeout, chp, sc_xfer->timeout * hz / 1000);
-	} else if (drvp->atapi_cap & ACAP_DSC)
-		drvp->drive_flags |= DRIVE_DSCWAIT;
-	return (1);
-
- unexpected_state:
+	xfer->expect_irq = 1;
+	xfer->next = wdc_atapi_intr_for_us;
 
-	/* If we're in polling mode, then it's possible we caught
-	   a drive in some awkward, intermediate state. Of course,
-	   the drive should have BSY set while it's transitioning
-           through awkward states, but this may not always
-           be the case. */
-
-	/* Spurious interrupts can cause us pain too and we don't deal
-	   with those nearly as well. We assume the spurious
-	   interrupts are random and won't affect us on retry */
-	if (xfer->c_flags & C_POLL) {
-		DELAY(1000);
-		as->retries++;
-		/* Give the drive up to 2 seconds to fix itself */
-		if (as->retries <= 2000)
-			return (1);
-	}
-
-	if (message) 
-		printf ("wdc_atapi_intr_drq: %s\n", message);
-
-	if (xfer->c_flags & C_DMA) {
-		(*chp->wdc->dma_finish)(chp->wdc->dma_arg,
-		    chp->channel, xfer->drive, dma_flags);
-		drvp->n_dmaerrs++;
-	}
-
-	sc_xfer->error = XS_RESET;
-	wdc_atapi_reset(chp, xfer);
-
-	return (1);
+	return (GOTO_NEXT);
 }
 
 
 int
-wdc_atapi_intr_complete(chp, xfer, dma_flags)
+wdc_atapi_intr_complete(chp, xfer, timeout)
 	struct channel_softc *chp;
 	struct wdc_xfer *xfer;
-	int dma_flags;
+	int timeout;
 
 {
 	struct scsi_xfer *sc_xfer = xfer->cmd;
 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
 	struct atapiscsi_softc *as = sc_xfer->sc_link->adapter_softc;
 	int dma_err = 0;
+	int dma_flags = wdc_atapi_dma_flags(xfer);
 
 	WDCDEBUG_PRINT(("PHASE_COMPLETED\n"), DEBUG_INTR);
 
@@ -856,12 +1052,8 @@ wdc_atapi_intr_complete(chp, xfer, dma_flags)
 		dma_err = (*chp->wdc->dma_finish)(chp->wdc->dma_arg,
 		     chp->channel, xfer->drive, dma_flags);
 
-		/* Assume everything was transferred 
-		   XXX - maybe we want to check the error register here */
-		if (xfer->c_flags & C_SENSE)
-			xfer->c_bcount -= sizeof(sc_xfer->sense);
-		else
-			xfer->c_bcount -= sc_xfer->datalen;
+		/* Assume everything was transferred */
+		xfer->c_bcount = 0;
 	}
 
 	as->protocol_phase = as_none;
@@ -872,8 +1064,8 @@ wdc_atapi_intr_complete(chp, xfer, dma_flags)
 				WDCDEBUG_PRINT(("wdc_atapi_intr: request_sense aborted, "
 						"calling wdc_atapi_done()"
 					), DEBUG_INTR);
-				wdc_atapi_done(chp, xfer);
-				return (1);
+				xfer->next = wdc_atapi_done;
+				return (GOTO_NEXT);
 			}
 
 			/*
@@ -882,8 +1074,9 @@ wdc_atapi_intr_complete(chp, xfer, dma_flags)
 			 */
 
 			sc_xfer->error = XS_RESET;
-			wdc_atapi_reset(chp, xfer);
-			return (1);
+			xfer->next = wdc_atapi_reset;
+			return (GOTO_NEXT);
+
 		} else if (xfer->c_bcount < sizeof(sc_xfer->sense)) {
 				/* use the sense we just read */
 			sc_xfer->error = XS_SENSE;
@@ -907,21 +1100,22 @@ wdc_atapi_intr_complete(chp, xfer, dma_flags)
 				 * 'request sense'
 				 */
 				xfer->databuf = &sc_xfer->sense;
-				xfer->c_bcount =
-					sizeof(sc_xfer->sense);
+				xfer->c_bcount = sizeof(sc_xfer->sense);
 				xfer->c_skip = 0;
+				xfer->c_done = NULL;
 				xfer->c_flags |= C_SENSE;
-				wdc_atapi_start(chp, xfer);
-				return (1);
+				xfer->next = wdc_atapi_real_start;
+				return (GOTO_NEXT);
 			}
-		} 
+		}		
 	}
 
         if (dma_err < 0) { 
 		drvp->n_dmaerrs++;
 		sc_xfer->error = XS_RESET;
-		wdc_atapi_reset(chp, xfer);
-		return (1);
+
+		xfer->next = wdc_atapi_reset;
+		return (GOTO_NEXT);
 	}
 			
 
@@ -939,98 +1133,113 @@ wdc_atapi_intr_complete(chp, xfer, dma_flags)
 	WDCDEBUG_PRINT(("wdc_atapi_intr: wdc_atapi_done() (end), error 0x%x "
 			"\n", sc_xfer->error),
 		       DEBUG_INTR);
-	wdc_atapi_done(chp, xfer);
-	return (1);
+
+
+	if (xfer->c_done) 
+		xfer->next = xfer->c_done;
+	else 
+		xfer->next = wdc_atapi_done;
+
+	return (GOTO_NEXT);
 }
 
 int
-wdc_atapi_intr(chp, xfer, irq)
+wdc_atapi_intr_for_us(chp, xfer, timeout)
 	struct channel_softc *chp;
 	struct wdc_xfer *xfer;
-	int irq;
+	int timeout;
+
 {
 	struct scsi_xfer *sc_xfer = xfer->cmd;
 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
 	struct atapiscsi_softc *as = sc_xfer->sc_link->adapter_softc;
-	int dma_flags = 0;
 
-	WDCDEBUG_PRINT(("wdc_atapi_intr %s:%d:%d\n",
-			chp->wdc->sc_dev.dv_xname, chp->channel, drvp->drive), 
-		       DEBUG_INTR);
+	WDCDEBUG_PRINT(("ATAPI_INTR\n"), DEBUG_INTR);
 
-	/* Is it not a transfer, but a control operation? */
-	if (drvp->state < READY) {
-		printf("%s:%d:%d: bad state %d in wdc_atapi_intr\n",
-		       chp->wdc->sc_dev.dv_xname, chp->channel, xfer->drive,
-		       drvp->state);
-		panic("wdc_atapi_intr: bad state\n");
-	}
+	/* If we missed an IRQ and were using DMA, flag it as a DMA error */
 
 	/* We should really wait_for_unbusy here too before 
 	   switching drives. */
 	CHP_WRITE_REG(chp, wdr_sdh, WDSD_IBM | (xfer->drive << 4));
+	DELAY (1);
 
-	/* Ack interrupt done in wait_for_unbusy */
-	if (wait_for_unbusy(chp,
-			    (irq == 0) ? sc_xfer->timeout : 0) != 0) {
-		if (irq && (xfer->c_flags & C_TIMEOU) == 0)
-			return (0); /* IRQ was not for us */
-		printf("%s:%d:%d: device timeout, c_bcount=%d, c_skip=%d\n",
-		       chp->wdc->sc_dev.dv_xname, chp->channel, xfer->drive,
-		       xfer->c_bcount, xfer->c_skip);
-		if (xfer->c_flags & C_DMA)
-			drvp->n_dmaerrs++;
-		sc_xfer->error = XS_TIMEOUT;
-		wdc_atapi_reset(chp, xfer);
-		return (1);
+	wdc_atapi_update_status(chp);
+
+	if (chp->ch_status & WDCS_BSY) {
+		if (timeout) {
+			printf("%s:%d:%d: device timeout, c_bcount=%d, c_skip=%d\n",
+			    chp->wdc->sc_dev.dv_xname, chp->channel, xfer->drive,
+			    xfer->c_bcount, xfer->c_skip);
+
+			if (xfer->c_flags & C_DMA)
+				drvp->n_dmaerrs++;
+
+			sc_xfer->error = XS_TIMEOUT;
+			xfer->next = wdc_atapi_reset;
+			return (GOTO_NEXT);
+		} else {
+			return (CONTINUE_POLL);
+		}
 	}
-	/* If we missed an IRQ and were using DMA, flag it as a DMA error */
-	if ((xfer->c_flags & C_TIMEOU) && (xfer->c_flags & C_DMA))
-		drvp->n_dmaerrs++;
 
-	/* DRQ was dropped. This means the command is over.
-	   Do cleanup, check for errors, etc. */
-	if (xfer->c_flags & C_DMA) {
-		dma_flags = ((sc_xfer->flags & SCSI_DATA_IN) ||
-			     (xfer->c_flags & C_SENSE)) ?  WDC_DMA_READ : 0;
-		dma_flags |= ((sc_xfer->flags & SCSI_POLL) ||
-			      (drvp->atapi_cap & ACAP_DSC)) ? WDC_DMA_POLL : 0;
+	if (as->protocol_phase != as_cmdout &&
+	    (xfer->c_flags & C_MEDIA_ACCESS) &&
+	    !(chp->ch_status & WDCS_DSC)) {
+		xfer->delay = 100;
+		return (CONTINUE_POLL);
 	}
 
+	xfer->claim_irq = 1;
+
+	if ((xfer->c_flags & C_TIMEOU) && (xfer->c_flags & C_DMA))
+		drvp->n_dmaerrs++;
+
 	if (chp->ch_status & WDCS_DRQ) {
 		if (as->protocol_phase == as_cmdout)
-			return (wdc_atapi_intr_command(chp, xfer, dma_flags));
+			return (wdc_atapi_intr_command(chp, xfer, timeout));
+	       
+		if (!(xfer->c_flags & C_DMA))
+			return (wdc_atapi_intr_data(chp, xfer, timeout));
 		else
-			return (wdc_atapi_intr_data(chp, xfer, dma_flags));
-	} else
-		return (wdc_atapi_intr_complete(chp, xfer, dma_flags));	
+			return (CONTINUE_POLL);
+	}
+	
+	return (wdc_atapi_intr_complete(chp, xfer, timeout));
 }
 
 int
-wdc_atapi_ctrl(chp, xfer, irq)
+wdc_atapi_ctrl(chp, xfer, timeout)
 	struct channel_softc *chp;
 	struct wdc_xfer *xfer;
-	int irq;
+	int timeout;
 {
 	struct scsi_xfer *sc_xfer = xfer->cmd;
 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
 	char *errstring = NULL;
-	int delay;
 
 	/* Ack interrupt done in wait_for_unbusy */
-again:
-	delay = (xfer->c_flags & C_POLL) ? 4000 : ((irq == 0) ? ATAPI_DELAY : 1);
+	CHP_WRITE_REG(chp, wdr_sdh, WDSD_IBM | (xfer->drive << 4));
+	delay (1);
+
+	if (timeout) {
+		if (drvp->state == IDENTIFY_WAIT ||
+		    drvp->state == PIOMODE ||
+		    drvp->state == PIOMODE_WAIT ||
+		    drvp->state == DMAMODE_WAIT)
+			goto timeout;
+	} else {
+		wdc_atapi_update_status(chp);
+	
+		if (chp->ch_status & WDCS_BSY)
+			return (CONTINUE_POLL);
+	}
+
+	xfer->claim_irq = 1;
+
 	WDCDEBUG_PRINT(("wdc_atapi_ctrl %s:%d:%d state %d\n",
 	    chp->wdc->sc_dev.dv_xname, chp->channel, drvp->drive, drvp->state),
 	    DEBUG_INTR | DEBUG_FUNCS);
 
-	/* We shouldn't have to select the drive in these states.
-	   If we do, there are other, more serious problems */
-	if (drvp->state != IDENTIFY_WAIT &&
-	    drvp->state != PIOMODE_WAIT &&
-	    drvp->state != DMAMODE_WAIT)
-		wdc_select_drive(chp, xfer->drive, delay);
-
 	/* Don't timeout during configuration */
 	xfer->c_flags &= ~C_TIMEOU;
 
@@ -1042,17 +1251,13 @@ again:
 	case IDENTIFY:
 		wdccommandshort(chp, drvp->drive, ATAPI_IDENTIFY_DEVICE);
 		drvp->state = IDENTIFY_WAIT;
+		xfer->timeout = ATAPI_CTRL_WAIT;
+		xfer->expect_irq = 1;
 		break;
 	
 	case IDENTIFY_WAIT:
 		errstring = "IDENTIFY";
 		
-		/* Some ATAPI devices need to try to read the media
-		   before responding. Well, let's hope resets while
-		   polling are few and far between */
-		if (wdcwait(chp, 0, 0, delay))
-			goto timeout;
-
 		/* We don't really care if this operation failed.
 		   It's just there to wake the drive from its stupor. */
 		if (!(chp->ch_status & WDCS_ERR)) {
@@ -1060,11 +1265,13 @@ again:
 	
 			errstring = "Post IDENTIFY";
 
-			if (wdcwait(chp, WDCS_DRQ, 0, 100))
-				goto timeout;
+			xfer->timeout = 100;
+			drvp->state = PIOMODE;
+			break;
 		}
 
 		drvp->state = PIOMODE;
+
 	case PIOMODE:
 piomode:
 		/* Don't try to set mode if controller can't be adjusted */
@@ -1076,11 +1283,11 @@ piomode:
 		wdccommand(chp, drvp->drive, SET_FEATURES, 0, 0, 0,
 		    0x08 | drvp->PIO_mode, WDSF_SET_MODE);
 		drvp->state = PIOMODE_WAIT;
+		xfer->timeout = ATAPI_CTRL_WAIT;
+		xfer->expect_irq = 1;
 		break;
 	case PIOMODE_WAIT:
 		errstring = "piomode";
-		if (wait_for_unbusy(chp, delay))
-			goto timeout;
 		if (chp->ch_status & WDCS_ERR) {
 			if (drvp->PIO_mode < 3) {
 				drvp->PIO_mode = 3;
@@ -1102,11 +1309,13 @@ piomode:
 			goto ready;
 		}
 		drvp->state = DMAMODE_WAIT;
+
+		xfer->timeout = ATAPI_CTRL_WAIT;
+		xfer->expect_irq = 1;
 		break;
+
 	case DMAMODE_WAIT:
 		errstring = "dmamode";
-		if (wait_for_unbusy(chp, delay))
-			goto timeout;
 		if (chp->ch_status & WDCS_ERR)
 			goto error;
 	/* fall through */
@@ -1114,29 +1323,18 @@ piomode:
 	case READY:
 	ready:
 		drvp->state = READY;
-		xfer->c_intr = wdc_atapi_intr;
-		wdc_atapi_start(chp, xfer);
-		return (1);
-	}
-	if ((sc_xfer->flags & SCSI_POLL) == 0 &&
-	    (drvp->atapi_cap & ACAP_DSC) == 0) {
-		chp->ch_flags |= WDCF_IRQ_WAIT;
-		xfer->c_intr = wdc_atapi_ctrl;
-		timeout(wdctimeout, chp, sc_xfer->timeout * hz / 1000);
-	} else {
-		goto again;
+		xfer->next = wdc_atapi_real_start;
+		break;
 	}
-	return (1);
+	return (GOTO_NEXT);
 
 timeout:
-	if (irq && (xfer->c_flags & C_TIMEOU) == 0) {
-		return (0); /* IRQ was not for us */
-	}
 	printf("%s:%d:%d: %s timed out\n",
 	    chp->wdc->sc_dev.dv_xname, chp->channel, xfer->drive, errstring);
 	sc_xfer->error = XS_TIMEOUT;
-	wdc_atapi_reset(chp, xfer);
-	return (1);
+	xfer->next = wdc_atapi_reset;
+	return (GOTO_NEXT);
+
 error:
 	printf("%s:%d:%d: %s ",
 	    chp->wdc->sc_dev.dv_xname, chp->channel, xfer->drive,
@@ -1144,14 +1342,41 @@ error:
 	printf("error (0x%x)\n", chp->ch_error);
 	sc_xfer->error = XS_SHORTSENSE;
 	atapi_to_scsi_sense(sc_xfer, chp->ch_error);
-	wdc_atapi_reset(chp, xfer);
-	return (1);
+	xfer->next = wdc_atapi_reset;
+	return (GOTO_NEXT);
 }
 
-void
-wdc_atapi_done(chp, xfer)
+int
+wdc_atapi_tape_done(chp, xfer, timeout)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int timeout;
+{
+	struct scsi_xfer *sc_xfer = xfer->cmd;
+
+	if (sc_xfer->error != XS_NOERROR) {
+		xfer->next = wdc_atapi_done;
+		return (GOTO_NEXT);
+	}
+
+	_lto3b(xfer->transfer_len,
+	    ((struct scsi_rw_tape *)
+		sc_xfer->cmd)->len);
+
+	xfer->c_bcount = sc_xfer->datalen;
+	xfer->c_done = NULL;
+	xfer->c_skip = 0;
+
+	xfer->next = wdc_atapi_real_start;
+	return (GOTO_NEXT);
+}
+
+	
+int
+wdc_atapi_done(chp, xfer, timeout)
 	struct channel_softc *chp;
 	struct wdc_xfer *xfer;
+	int timeout;
 {
 	struct scsi_xfer *sc_xfer = xfer->cmd;
 	int need_done = xfer->c_flags & C_NEEDDONE;
@@ -1161,8 +1386,7 @@ wdc_atapi_done(chp, xfer)
 	WDCDEBUG_PRINT(("wdc_atapi_done %s:%d:%d: flags 0x%x\n",
 	    chp->wdc->sc_dev.dv_xname, chp->channel, xfer->drive,
 	    (u_int)xfer->c_flags), DEBUG_XFERS);
-	/* remove this command from xfer queue */
-	wdc_free_xfer(chp, xfer);
+
 	sc_xfer->flags |= ITSDONE;
 	if (drvp->n_dmaerrs ||
 	    (sc_xfer->error != XS_NOERROR && sc_xfer->error != XS_SENSE &&
@@ -1174,111 +1398,63 @@ wdc_atapi_done(chp, xfer)
 		if (doing_dma)
 			wdc_downgrade_mode(drvp);
 	}
-	    
+
 	if (need_done) {
 		WDCDEBUG_PRINT(("wdc_atapi_done: scsi_done\n"), DEBUG_XFERS);
 		scsi_done(sc_xfer);
 	}
-	WDCDEBUG_PRINT(("wdcstart from wdc_atapi_done, flags 0x%x\n",
-	    chp->ch_flags), DEBUG_XFERS);
-	wdcstart(chp);
-}
-
-/* Wait until DSC gets asserted.  */
-int
-atapi_dsc_wait(drvp, timo)
-	struct ata_drive_datas *drvp;
-	int timo;
-{
-	struct channel_softc *chp = drvp->chnl_softc;
 
-	chp->ch_flags &= ~WDCF_ACTIVE;
-#if 0
-	/* XXX Something like this may be needed I have not investigated
-	   close enough yet.  If so we may need to put it back after
-	   the poll wait.  */
-	TAILQ_REMOVE(&chp->ch_queue->sc_xfer, xfer, c_xferchain);
-#endif
-	return (atapi_poll_wait(atapi_dsc_ready, drvp, timo, PZERO + PCATCH,
-	    "atapidsc"));
+	return (DONE);
 }
 
-int
-atapi_dsc_ready(arg)
-	void *arg;
-{
-	struct ata_drive_datas *drvp = arg;
-	struct channel_softc *chp = drvp->chnl_softc;
-
-	if (chp->ch_flags & WDCF_ACTIVE)
-		return (0);
-	wdc_select_drive(chp, drvp->drive, 0);
-	chp->ch_status = CHP_READ_REG(chp, wdr_status);
-	return ((chp->ch_status & (WDCS_BSY | WDCS_DSC)) == WDCS_DSC);
-}
 
 int
-atapi_poll_wait(ready, arg, timo, pri, msg)
-	int (*ready) __P((void *));
-	void *arg;
-	int timo;
-	int pri;
-	char *msg;
-{
-	int maxtic, tic = 0, error;
-	u_int64_t starttime = time.tv_sec * 1000 + time.tv_usec / 1000;
-	u_int64_t endtime = starttime + timo;
-
-	while (1) {
-		WDCDEBUG_PRINT(("atapi_poll_wait: msg=%s tic=%d\n", msg, tic),
-		    DEBUG_POLL);
-		if (ready(arg))
-			return (0);
-
-#if 0
-		/* Exponential backoff.  */
-		tic = tic + tic + 1;
-#else
-		tic = min(hz / 100, 1);
-#endif
-		maxtic = (int)
-		    (endtime - (time.tv_sec * 1000 + time.tv_usec / 1000));
-		if (maxtic <= 0)
-			return (EWOULDBLOCK);
-		if (tic > maxtic)
-			tic = maxtic;
-		if (tic > ATAPI_POLL_MAXTIC)
-			tic = ATAPI_POLL_MAXTIC;
-		error = tsleep(arg, pri, msg, tic);
-		if (error != EWOULDBLOCK)
-			return (error);
-	}
-}
-
-void
-wdc_atapi_reset(chp, xfer)
+wdc_atapi_reset(chp, xfer, timeout)
 	struct channel_softc *chp;
 	struct wdc_xfer *xfer;
+	int timeout;
 {
 	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
-	struct scsi_xfer *sc_xfer = xfer->cmd;
 
 	wdccommandshort(chp, xfer->drive, ATAPI_SOFT_RESET);
+	drvp->state = 0;
 
 	/* Some ATAPI devices need extra time to find their
 	   brains after a reset
 	 */
-	delay(5000);
+	xfer->next = wdc_atapi_reset_2;
+	xfer->delay = 10;
+	xfer->timeout = ATAPI_RESET_WAIT;
+	return (GOTO_NEXT);
+}
 
-	drvp->state = 0;
-	if (wdcwait(chp, WDCS_DRQ, 0, ATAPI_RESET_WAIT) != 0) {
+int
+wdc_atapi_reset_2(chp, xfer, timeout)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int timeout;
+{
+	struct ata_drive_datas *drvp = &chp->ch_drive[xfer->drive];
+	struct scsi_xfer *sc_xfer = xfer->cmd;
+	
+	if (timeout) {
 		printf("%s:%d:%d: reset failed\n",
 		    chp->wdc->sc_dev.dv_xname, chp->channel,
 		    xfer->drive);
 		sc_xfer->error = XS_SELTIMEOUT;
 		wdc_reset_channel(drvp);
+		
+		xfer->next = wdc_atapi_done;
+		return (GOTO_NEXT);
 	}
 
-	wdc_atapi_done(chp, xfer);
-	return;
+	wdc_atapi_update_status(chp);
+
+	if (chp->ch_status & (WDCS_BSY | WDCS_DRQ)) {
+		return (CONTINUE_POLL);
+	}
+
+	xfer->next = wdc_atapi_done;
+	return (GOTO_NEXT);
 }
+
diff --git a/sys/dev/ic/wdcvar.h b/sys/dev/ic/wdcvar.h
index cfe869793ea..c0b18b6574b 100644
--- a/sys/dev/ic/wdcvar.h
+++ b/sys/dev/ic/wdcvar.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: wdcvar.h,v 1.5 1999/11/17 01:22:56 csapuntz Exp $     */
+/*      $OpenBSD: wdcvar.h,v 1.6 1999/12/11 10:15:03 csapuntz Exp $     */
 /*	$NetBSD: wdcvar.h,v 1.17 1999/04/11 20:50:29 bouyer Exp $	*/
 
 /*-
@@ -188,6 +188,8 @@ struct wdc_xfer {
 #define C_POLL		0x0020 /* cmd is polled */
 #define C_DMA		0x0040 /* cmd uses DMA */
 #define C_SENSE		0x0080 /* cmd is a internal command */
+#define C_MEDIA_ACCESS  0x0100 /* is a media access command */
+#define C_POLL_MACHINE  0x0200 /* machine has a poll hander */
 
 	/* Informations about our location */
 	struct channel_softc *chp;
@@ -202,6 +204,19 @@ struct wdc_xfer {
 	LIST_ENTRY(wdc_xfer) free_list;
 	void (*c_start) __P((struct channel_softc *, struct wdc_xfer *));
 	int  (*c_intr)  __P((struct channel_softc *, struct wdc_xfer *, int));
+	int (*c_done)  __P((struct channel_softc *, struct wdc_xfer *, int));
+
+	/* Used by ATAPISCSI */
+	int timeout;
+	u_int64_t endtime;
+	int delay;
+	unsigned int expect_irq:1;
+	unsigned int claim_irq:1;
+
+	int (*next) __P((struct channel_softc *, struct wdc_xfer *, int));
+	
+	/* Used for tape devices */
+	int  transfer_len;
 };
 
 /*