diff --git a/sys/dev/ata/ata-all.c b/sys/dev/ata/ata-all.c
index ebd069c7e336..59eec52e57cd 100644
--- a/sys/dev/ata/ata-all.c
+++ b/sys/dev/ata/ata-all.c
@@ -112,6 +112,19 @@ ata_probe(device_t dev)
     if (ch->r_irq)
 	return EEXIST;
 
+    return 0;
+}
+
+
+int
+ata_attach(device_t dev)
+{
+    struct ata_channel *ch;
+    int error, rid;
+
+    if (!dev || !(ch = device_get_softc(dev)))
+	return ENXIO;
+
     /* initialize the softc basics */
     ch->device[MASTER].channel = ch;
     ch->device[MASTER].unit = ATA_MASTER;
@@ -126,17 +139,6 @@ ata_probe(device_t dev)
     ch->locking(ch, ATA_LF_LOCK);
     ch->hw.reset(ch);
     ch->locking(ch, ATA_LF_UNLOCK);
-    return 0;
-}
-
-int
-ata_attach(device_t dev)
-{
-    struct ata_channel *ch;
-    int error, rid;
-
-    if (!dev || !(ch = device_get_softc(dev)))
-	return ENXIO;
 
     rid = ATA_IRQ_RID;
     ch->r_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
@@ -151,9 +153,6 @@ ata_attach(device_t dev)
 	return error;
     }
 
-    if (ch->dma)
-	ch->dma->alloc(ch);
-
     /* initialize queue and associated lock */
     bzero(&ch->queue_mtx, sizeof(struct mtx));
     mtx_init(&ch->queue_mtx, "ATA queue lock", NULL, MTX_DEF);
@@ -223,9 +222,6 @@ ata_detach(device_t dev)
     ch->device[SLAVE].mode = ATA_PIO;
     ch->devices = 0;
 
-    if (ch->dma)
-	ch->dma->free(ch);
-
     bus_teardown_intr(dev, ch->r_irq, ch->ih);
     bus_release_resource(dev, SYS_RES_IRQ, ATA_IRQ_RID, ch->r_irq);
     ch->r_irq = NULL;
@@ -306,6 +302,7 @@ ata_suspend(device_t dev)
 
     if (!dev || !(ch = device_get_softc(dev)))
 	return ENXIO;
+
     ch->locking(ch, ATA_LF_LOCK);
     ATA_SLEEPLOCK_CH(ch);
     return 0;
diff --git a/sys/dev/ata/ata-chipset.c b/sys/dev/ata/ata-chipset.c
index 69ecee52ce1e..8f9084c6ff14 100644
--- a/sys/dev/ata/ata-chipset.c
+++ b/sys/dev/ata/ata-chipset.c
@@ -185,7 +185,7 @@ ata_sata_setmode(struct ata_device *atadev, int mode)
      * if we detect that the device isn't a real SATA device we limit 
      * the transfer mode to UDMA5/ATA100.
      * this works around the problems some devices has with the 
-     * Marvell SATA->PATA converters and UDMA6/ATA133.
+     * Marvell 88SX8030 SATA->PATA converters and UDMA6/ATA133.
      */
     if (atadev->param->satacapabilities != 0x0000 &&
 	atadev->param->satacapabilities != 0xffff)
@@ -1365,7 +1365,6 @@ ata_promise_mio_allocate(device_t dev, struct ata_channel *ch)
     ch->r_io[ATA_IDX_ADDR].res = ctlr->r_res2;
     ch->flags |= ATA_USE_16BIT;
 
-    ctlr->dmainit(ch);	
     ata_generic_hw(ch);
     if (ctlr->chip->cfg2 & PRSX4X)
 	ch->hw.command = ata_promise_sx4_command;
@@ -2141,8 +2140,7 @@ ata_sii_allocate(device_t dev, struct ata_channel *ch)
     if (ctlr->chip->max_dma >= ATA_SA150)
 	ch->flags |= ATA_NO_SLAVE;
 
-    ctlr->dmainit(ch);
-    if (ctlr->chip->cfg2 & SIIBUG)
+    if ((ctlr->chip->cfg2 & SIIBUG) && ch->dma)
 	ch->dma->boundary = 8 * 1024;
 
     ata_generic_hw(ch);
diff --git a/sys/dev/ata/ata-dma.c b/sys/dev/ata/ata-dma.c
index 910ffddca72d..903dca1d20ee 100644
--- a/sys/dev/ata/ata-dma.c
+++ b/sys/dev/ata/ata-dma.c
@@ -59,7 +59,7 @@ static MALLOC_DEFINE(M_ATADMA, "ATA DMA", "ATA driver DMA");
 /* misc defines */
 #define MAXSEGSZ	PAGE_SIZE
 #define MAXTABSZ	PAGE_SIZE
-#define MAXWSPCSZ	256
+#define MAXWSPCSZ	PAGE_SIZE
 #define MAXCTLDMASZ	(2 * (MAXTABSZ + MAXPHYS))
 
 struct ata_dc_cb_args {
diff --git a/sys/dev/ata/ata-pci.c b/sys/dev/ata/ata-pci.c
index 24691488c2ad..61e33a093ecd 100644
--- a/sys/dev/ata/ata-pci.c
+++ b/sys/dev/ata/ata-pci.c
@@ -241,13 +241,8 @@ ata_pci_print_child(device_t dev, device_t child)
     int retval = 0;
 
     retval += bus_print_child_header(dev, child);
-    retval += printf(": at 0x%lx", rman_get_start(ch->r_io[ATA_IDX_ADDR].res));
-
-    if (ata_legacy(dev))
-	retval += printf(" irq %d", 14 + ch->unit);
-    
+    retval += printf(": channel #%d", ch->unit);
     retval += bus_print_child_footer(dev, child);
-
     return retval;
 }
 
@@ -428,15 +423,6 @@ ata_pci_allocate(device_t dev, struct ata_channel *ch)
 	    ch->r_io[i].res = ctlr->r_res1;
 	    ch->r_io[i].offset = (i - ATA_BMCMD_PORT)+(ch->unit * ATA_BMIOSIZE);
 	}
-
-	/* if simplex controller, only allow DMA on primary channel */
-	ATA_IDX_OUTB(ch, ATA_BMSTAT_PORT, ATA_IDX_INB(ch, ATA_BMSTAT_PORT) &
-		     (ATA_BMSTAT_DMA_MASTER | ATA_BMSTAT_DMA_SLAVE));
-	if (ch->unit > 0 &&
-	    (ATA_IDX_INB(ch, ATA_BMSTAT_PORT) & ATA_BMSTAT_DMA_SIMPLEX))
-	    device_printf(dev, "simplex device, DMA on primary only\n");
-	else 
-	    ctlr->dmainit(ch);
     }
 
     ata_generic_hw(ch);
@@ -517,12 +503,11 @@ static devclass_t ata_pci_devclass;
 DRIVER_MODULE(atapci, pci, ata_pci_driver, ata_pci_devclass, 0, 0);
 
 static int
-ata_pcisub_probe(device_t dev)
+ata_channel_probe(device_t dev)
 {
-    struct ata_pci_controller *ctlr = device_get_softc(device_get_parent(dev));
     struct ata_channel *ch = device_get_softc(dev);
     device_t *children;
-    int count, error, i;
+    int count, i;
 
     /* take care of green memory */
     bzero(ch, sizeof(struct ata_channel));
@@ -535,31 +520,60 @@ ata_pcisub_probe(device_t dev)
     }
     free(children, M_TEMP);
 
+    return ata_probe(dev);
+}
+
+static int
+ata_channel_attach(device_t dev)
+{
+    struct ata_pci_controller *ctlr = device_get_softc(device_get_parent(dev));
+    struct ata_channel *ch = device_get_softc(dev);
+    int error;
+
     ch->device[MASTER].setmode = ctlr->setmode;
     ch->device[SLAVE].setmode = ctlr->setmode;
     ch->locking = ctlr->locking;
     ch->reset = ctlr->reset;
 
+    ctlr->dmainit(ch);
+    if (ch->dma)
+	ch->dma->alloc(ch);
+
     if ((error = ctlr->allocate(dev, ch)))
 	return error;
 
-    return ata_probe(dev);
+    return ata_attach(dev);
 }
 
-static device_method_t ata_pcisub_methods[] = {
+static int
+ata_channel_detach(device_t dev)
+{
+    struct ata_channel *ch = device_get_softc(dev);
+    int error;
+
+    if ((error = ata_detach(dev)))
+	return error;
+
+    if (ch->dma)
+	ch->dma->free(ch);
+
+    return 0;
+}
+
+static device_method_t ata_channel_methods[] = {
     /* device interface */
-    DEVMETHOD(device_probe,	ata_pcisub_probe),
-    DEVMETHOD(device_attach,	ata_attach),
-    DEVMETHOD(device_detach,	ata_detach),
+    DEVMETHOD(device_probe,	ata_channel_probe),
+    DEVMETHOD(device_attach,	ata_channel_attach),
+    DEVMETHOD(device_detach,	ata_channel_detach),
     DEVMETHOD(device_suspend,	ata_suspend),
     DEVMETHOD(device_resume,	ata_resume),
     { 0, 0 }
 };
 
-static driver_t ata_pcisub_driver = {
+static driver_t ata_channel_driver = {
     "ata",
-    ata_pcisub_methods,
+    ata_channel_methods,
     sizeof(struct ata_channel),
 };
 
-DRIVER_MODULE(ata, atapci, ata_pcisub_driver, ata_devclass, 0, 0);
+DRIVER_MODULE(ata, atapci, ata_channel_driver, ata_devclass, 0, 0);