Merge an old fix from NetBSD:

- do not stop/unload current DMA operation if an IRQ was not detected
  by DMA engine unless the force flag was given, fixes DMA problems
  in shared IRQ setups;
- ack interrupt before entering DMA codepath

Tested by many.
Work by niklas@ but he doesn't want to commit it for some reason.

6 files changed, 69 insertions, 32 deletions

diff --git a/sys/dev/ata/ata_wdc.c b/sys/dev/ata/ata_wdc.c
index 10d934b217c..9ea56043b7a 100644
--- a/sys/dev/ata/ata_wdc.c
+++ b/sys/dev/ata/ata_wdc.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: ata_wdc.c,v 1.23 2003/10/16 11:30:00 grange Exp $	*/
+/*      $OpenBSD: ata_wdc.c,v 1.24 2003/10/17 08:14:09 grange Exp $	*/
 /*	$NetBSD: ata_wdc.c,v 1.21 1999/08/09 09:43:11 bouyer Exp $	*/
 
 /*
@@ -315,6 +315,7 @@ again:
 			/* start the DMA channel */
 			(*chp->wdc->dma_start)(chp->wdc->dma_arg,
 			    chp->channel, xfer->drive);
+			chp->ch_flags |= WDCF_DMA_WAIT;
 			/* wait for irq */
 			goto intr;
 		} /* else not DMA */
@@ -382,6 +383,10 @@ intr:	/* Wait for IRQ (either real or polled) */
 	} else {
 		/* Wait for at last 400ns for status bit to be valid */
 		delay(1);
+		if (chp->ch_flags & WDCF_DMA_WAIT) {
+			wdc_dmawait(chp, xfer, ATA_DELAY);
+			chp->ch_flags &= ~WDCF_DMA_WAIT;
+		}
 		wdc_ata_bio_intr(chp, xfer, 0);
 		if ((ata_bio->flags & ATA_ITSDONE) == 0)
 			goto again;
@@ -438,14 +443,12 @@ wdc_ata_bio_intr(chp, xfer, irq)
 
 		goto timeout;
 	}
+	if (chp->wdc->cap & WDC_CAPABILITY_IRQACK)
+		chp->wdc->irqack(chp);
 
 	drv_err = wdc_ata_err(drvp, ata_bio);
 
 	if (xfer->c_flags & C_DMA) {
-		chp->wdc->dma_status =
-		    (*chp->wdc->dma_finish)(chp->wdc->dma_arg,
-			chp->channel, xfer->drive);
-
 		if (chp->wdc->dma_status != 0) {
 			if (drv_err != WDC_ATA_ERR) {
 				ata_bio->error = ERR_DMA;
@@ -466,9 +469,6 @@ wdc_ata_bio_intr(chp, xfer, irq)
 		ata_dmaerr(drvp);
 	}
 
-	if (chp->wdc->cap & WDC_CAPABILITY_IRQACK)
-		chp->wdc->irqack(chp);
-
 	/* if we had an error, end */
 	if (drv_err == WDC_ATA_ERR) {
 		wdc_ata_bio_done(chp, xfer);
@@ -509,12 +509,8 @@ end:
 	return 1;
 
 timeout:
-	if (xfer->c_flags & C_DMA) {
-		chp->wdc->dma_status =
-		    (*chp->wdc->dma_finish)(chp->wdc->dma_arg,
-			chp->channel, xfer->drive);
+	if (xfer->c_flags & C_DMA)
 		ata_dmaerr(drvp);
-	}
 
 	ata_bio->error = TIMEOUT;
 	wdc_ata_bio_done(chp, xfer);
diff --git a/sys/dev/atapiscsi/atapiscsi.c b/sys/dev/atapiscsi/atapiscsi.c
index ae8ab9f5beb..78e7f3417c4 100644
--- a/sys/dev/atapiscsi/atapiscsi.c
+++ b/sys/dev/atapiscsi/atapiscsi.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: atapiscsi.c,v 1.65 2003/10/16 11:30:00 grange Exp $     */
+/*      $OpenBSD: atapiscsi.c,v 1.66 2003/10/17 08:14:09 grange Exp $     */
 
 /*
  * This code is derived from code with the copyright below.
@@ -1101,11 +1101,6 @@ wdc_atapi_intr_complete(chp, xfer, timeout, ret)
 		int retry;
 
 		if (timeout) {
-			chp->wdc->dma_status =
-			    (*chp->wdc->dma_finish)
-			    (chp->wdc->dma_arg, chp->channel,
-				xfer->drive);
-
 			sc_xfer->error = XS_TIMEOUT;
 			ata_dmaerr(drvp);
 
@@ -1127,7 +1122,7 @@ wdc_atapi_intr_complete(chp, xfer, timeout, ret)
 		chp->wdc->dma_status =
 		    (*chp->wdc->dma_finish)
 		    (chp->wdc->dma_arg, chp->channel,
-			xfer->drive);
+			xfer->drive, 1);
 
 		if (chp->wdc->dma_status & WDC_DMAST_UNDER)
 			xfer->c_bcount = 1;
diff --git a/sys/dev/ic/wdc.c b/sys/dev/ic/wdc.c
index 966bb79f250..80fea5b6198 100644
--- a/sys/dev/ic/wdc.c
+++ b/sys/dev/ic/wdc.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: wdc.c,v 1.66 2003/10/16 11:58:16 grange Exp $     */
+/*      $OpenBSD: wdc.c,v 1.67 2003/10/17 08:14:09 grange Exp $     */
 /*	$NetBSD: wdc.c,v 1.68 1999/06/23 19:00:17 bouyer Exp $ */
 
 
@@ -988,6 +988,16 @@ wdcintr(arg)
 
 	WDCDEBUG_PRINT(("wdcintr\n"), DEBUG_INTR);
 	xfer = TAILQ_FIRST(&chp->ch_queue->sc_xfer);
+	if (chp->ch_flags & WDCF_DMA_WAIT) {
+		chp->wdc->dma_status =
+		    (*chp->wdc->dma_finish)(chp->wdc->dma_arg, chp->channel,
+		    xfer->drive, 0);
+		if (chp->wdc->dma_status & WDC_DMAST_NOIRQ) {
+			/* IRQ not for us, not detected by DMA engine */
+			return 0;
+		}
+		chp->ch_flags &= ~WDCF_DMA_WAIT;
+	}
 	chp->ch_flags &= ~WDCF_IRQ_WAIT;
         ret = xfer->c_intr(chp, xfer, 1);
 	if (ret == 0)	/* irq was not for us, still waiting for irq */
@@ -1157,6 +1167,30 @@ wdc_wait_for_status(chp, mask, bits, timeout)
 	return time;
 }
 
+/*
+ * Busy-wait for DMA to complete
+ */
+int
+wdc_dmawait(chp, xfer, timeout)
+	struct channel_softc *chp;
+	struct wdc_xfer *xfer;
+	int timeout;
+{
+	int time;
+	for (time = 0;  time < timeout * 1000 / WDCDELAY; time++) {
+		chp->wdc->dma_status =
+		    (*chp->wdc->dma_finish)(chp->wdc->dma_arg,
+		    chp->channel, xfer->drive, 0);
+		if ((chp->wdc->dma_status & WDC_DMAST_NOIRQ) == 0)
+			return 0;
+		delay(WDCDELAY);
+	}
+	/* timeout, force a DMA halt */
+	chp->wdc->dma_status = (*chp->wdc->dma_finish)(chp->wdc->dma_arg,
+	    chp->channel, xfer->drive, 1);
+	return 1;
+}
+
 void
 wdctimeout(arg)
 	void *arg;
@@ -1182,6 +1216,12 @@ wdctimeout(arg)
 		    "atapi":"ata");
 		printf("\tc_bcount: %d\n", xfer->c_bcount);
 		printf("\tc_skip: %d\n", xfer->c_skip);
+		if (chp->ch_flags & WDCF_DMA_WAIT) {
+			chp->wdc->dma_status =
+			    (*chp->wdc->dma_finish)(chp->wdc->dma_arg,
+			    chp->channel, xfer->drive, 1);
+			chp->ch_flags &= ~WDCF_DMA_WAIT;
+		}
 		/*
 		 * Call the interrupt routine. If we just missed and interrupt,
 		 * it will do what's needed. Else, it will take the needed
diff --git a/sys/dev/ic/wdcvar.h b/sys/dev/ic/wdcvar.h
index e06341dc171..d093cd94193 100644
--- a/sys/dev/ic/wdcvar.h
+++ b/sys/dev/ic/wdcvar.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: wdcvar.h,v 1.30 2003/10/16 14:18:34 grange Exp $     */
+/*      $OpenBSD: wdcvar.h,v 1.31 2003/10/17 08:14:09 grange Exp $     */
 /*	$NetBSD: wdcvar.h,v 1.17 1999/04/11 20:50:29 bouyer Exp $	*/
 
 /*-
@@ -68,6 +68,7 @@ struct channel_softc { /* Per channel data */
 #define WDCF_ACTIVE		0x01 /* channel is active */
 #define WDCF_ONESLAVE		0x02 /* slave-only channel */
 #define WDCF_IRQ_WAIT		0x10 /* controller is waiting for irq */
+#define WDCF_DMA_WAIT		0x20 /* controller is waiting for DMA */
 #define WDCF_VERBOSE_PROBE	0x40 /* verbose probe */
 	u_int8_t ch_status;         /* copy of status register */
 	u_int8_t ch_prev_log_status; /* previous logged value of status reg */
@@ -175,7 +176,7 @@ struct wdc_softc { /* Per controller state */
 	int            (*dma_init)(void *, int, int, void *, size_t,
 	                int);
 	void           (*dma_start)(void *, int, int);
-	int            (*dma_finish)(void *, int, int);
+	int            (*dma_finish)(void *, int, int, int);
 /* flags passed to DMA functions */
 #define WDC_DMA_READ	0x01
 #define WDC_DMA_IRQW	0x02
diff --git a/sys/dev/isa/wdc_isa.c b/sys/dev/isa/wdc_isa.c
index c9cc5dbf20f..6c0a62e9fc3 100644
--- a/sys/dev/isa/wdc_isa.c
+++ b/sys/dev/isa/wdc_isa.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: wdc_isa.c,v 1.9 2002/03/14 03:16:05 millert Exp $     */
+/*      $OpenBSD: wdc_isa.c,v 1.10 2003/10/17 08:14:09 grange Exp $     */
 /*	$NetBSD: wdc_isa.c,v 1.15 1999/05/19 14:41:25 bouyer Exp $ */
 
 /*-
@@ -92,7 +92,7 @@ struct cfattach wdc_isa_ca = {
 static void	wdc_isa_dma_setup(struct wdc_isa_softc *);
 static int	wdc_isa_dma_init(void *, int, int, void *, size_t, int);
 static void 	wdc_isa_dma_start(void *, int, int);
-static int	wdc_isa_dma_finish(void *, int, int);
+static int	wdc_isa_dma_finish(void *, int, int, int);
 #endif	/* NISADMA > 0 */
 
 int
@@ -252,9 +252,10 @@ wdc_isa_dma_start(v, channel, drive)
 }
 
 static int
-wdc_isa_dma_finish(v, channel, drive)
+wdc_isa_dma_finish(v, channel, drive, force)
 	void *v;
 	int channel, drive;
+	int force;
 {
 	struct wdc_isa_softc *sc = v;
 
diff --git a/sys/dev/pci/pciide.c b/sys/dev/pci/pciide.c
index 1df19517202..8f1d947c22e 100644
--- a/sys/dev/pci/pciide.c
+++ b/sys/dev/pci/pciide.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pciide.c,v 1.143 2003/10/16 14:52:58 grange Exp $	*/
+/*	$OpenBSD: pciide.c,v 1.144 2003/10/17 08:14:09 grange Exp $	*/
 /*	$NetBSD: pciide.c,v 1.127 2001/08/03 01:31:08 tsutsui Exp $	*/
 
 /*
@@ -264,7 +264,7 @@ void pdc20268_setup_channel(struct channel_softc*);
 int  pdc202xx_pci_intr(void *);
 int  pdc20265_pci_intr(void *);
 void pdc20262_dma_start(void *, int, int);
-int  pdc20262_dma_finish(void *, int, int);
+int  pdc20262_dma_finish(void *, int, int, int);
 
 void opti_chip_map(struct pciide_softc*, struct pci_attach_args*);
 void opti_setup_channel(struct channel_softc*);
@@ -291,7 +291,7 @@ void pciide_channel_dma_setup(struct pciide_channel *);
 int  pciide_dma_table_setup(struct pciide_softc*, int, int);
 int  pciide_dma_init(void *, int, int, void *, size_t, int);
 void pciide_dma_start(void *, int, int);
-int  pciide_dma_finish(void *, int, int);
+int  pciide_dma_finish(void *, int, int, int);
 void pciide_irqack(struct channel_softc *);
 void pciide_print_modes(struct pciide_channel *);
 void pciide_print_channels(int, pcireg_t);
@@ -1306,9 +1306,10 @@ pciide_dma_start(v, channel, drive)
 }
 
 int
-pciide_dma_finish(v, channel, drive)
+pciide_dma_finish(v, channel, drive, force)
 	void *v;
 	int channel, drive;
+	int force;
 {
 	struct pciide_softc *sc = v;
 	u_int8_t status;
@@ -1323,6 +1324,9 @@ pciide_dma_finish(v, channel, drive)
 	WDCDEBUG_PRINT(("pciide_dma_finish: status 0x%x\n", status),
 	    DEBUG_XFERS);
 
+	if (force == 0 && (status & IDEDMA_CTL_INTR) == 0)
+		return WDC_DMAST_NOIRQ;
+
 	/* stop DMA channel */
 	bus_space_write_1(sc->sc_dma_iot, sc->sc_dma_ioh,
 	    IDEDMA_CMD(channel),
@@ -5150,7 +5154,7 @@ pdc20262_dma_start(void *v, int channel, int drive)
 }
 
 int
-pdc20262_dma_finish(void *v, int channel, int drive)
+pdc20262_dma_finish(void *v, int channel, int drive, int force)
 {
 	struct pciide_softc *sc = v;
 	struct pciide_dma_maps *dma_maps =
@@ -5166,7 +5170,7 @@ pdc20262_dma_finish(void *v, int channel, int drive)
 		    PDC262_ATAPI(channel), 0);
 	}
 
-	return (pciide_dma_finish(v, channel, drive));
+	return (pciide_dma_finish(v, channel, drive, force));
 }
 
 /*