[libata] sata_nv: add SW NCQ support for MCP51/MCP55/MCP61
authorKuan Luo <kluo@nvidia.com>
Mon, 15 Oct 2007 19:16:53 +0000 (15:16 -0400)
committerJeff Garzik <jeff@garzik.org>
Mon, 15 Oct 2007 19:16:53 +0000 (15:16 -0400)
Add the Software NCQ support to sata_nv.c for MCP51/MCP55/MCP61 SATA
controller.  NCQ function is disable by default, you can enable it
with 'swncq=1'.  NCQ will be turned off if the drive is Maxtor on
MCP51 or MCP55 rev 0xa2 platform.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Kuan Luo <kluo@nvidia.com>
Signed-off-by: Peer Chen <pchen@nvidia.com>
Cc: Zoltan Boszormenyi <zboszor@dunaweb.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
drivers/ata/sata_nv.c

index 40557fe..240a892 100644 (file)
@@ -169,6 +169,35 @@ enum {
        NV_ADMA_PORT_REGISTER_MODE      = (1 << 0),
        NV_ADMA_ATAPI_SETUP_COMPLETE    = (1 << 1),
 
+       /* MCP55 reg offset */
+       NV_CTL_MCP55                    = 0x400,
+       NV_INT_STATUS_MCP55             = 0x440,
+       NV_INT_ENABLE_MCP55             = 0x444,
+       NV_NCQ_REG_MCP55                = 0x448,
+
+       /* MCP55 */
+       NV_INT_ALL_MCP55                = 0xffff,
+       NV_INT_PORT_SHIFT_MCP55         = 16,   /* each port occupies 16 bits */
+       NV_INT_MASK_MCP55               = NV_INT_ALL_MCP55 & 0xfffd,
+
+       /* SWNCQ ENABLE BITS*/
+       NV_CTL_PRI_SWNCQ                = 0x02,
+       NV_CTL_SEC_SWNCQ                = 0x04,
+
+       /* SW NCQ status bits*/
+       NV_SWNCQ_IRQ_DEV                = (1 << 0),
+       NV_SWNCQ_IRQ_PM                 = (1 << 1),
+       NV_SWNCQ_IRQ_ADDED              = (1 << 2),
+       NV_SWNCQ_IRQ_REMOVED            = (1 << 3),
+
+       NV_SWNCQ_IRQ_BACKOUT            = (1 << 4),
+       NV_SWNCQ_IRQ_SDBFIS             = (1 << 5),
+       NV_SWNCQ_IRQ_DHREGFIS           = (1 << 6),
+       NV_SWNCQ_IRQ_DMASETUP           = (1 << 7),
+
+       NV_SWNCQ_IRQ_HOTPLUG            = NV_SWNCQ_IRQ_ADDED |
+                                         NV_SWNCQ_IRQ_REMOVED,
+
 };
 
 /* ADMA Physical Region Descriptor - one SG segment */
@@ -226,6 +255,42 @@ struct nv_host_priv {
        unsigned long           type;
 };
 
+struct defer_queue {
+       u32             defer_bits;
+       unsigned int    head;
+       unsigned int    tail;
+       unsigned int    tag[ATA_MAX_QUEUE];
+};
+
+enum ncq_saw_flag_list {
+       ncq_saw_d2h     = (1U << 0),
+       ncq_saw_dmas    = (1U << 1),
+       ncq_saw_sdb     = (1U << 2),
+       ncq_saw_backout = (1U << 3),
+};
+
+struct nv_swncq_port_priv {
+       struct ata_prd  *prd;    /* our SG list */
+       dma_addr_t      prd_dma; /* and its DMA mapping */
+       void __iomem    *sactive_block;
+       void __iomem    *irq_block;
+       void __iomem    *tag_block;
+       u32             qc_active;
+
+       unsigned int    last_issue_tag;
+
+       /* fifo circular queue to store deferral command */
+       struct defer_queue defer_queue;
+
+       /* for NCQ interrupt analysis */
+       u32             dhfis_bits;
+       u32             dmafis_bits;
+       u32             sdbfis_bits;
+
+       unsigned int    ncq_flags;
+};
+
+
 #define NV_ADMA_CHECK_INTR(GCTL, PORT) ((GCTL) & ( 1 << (19 + (12 * (PORT)))))
 
 static int nv_init_one (struct pci_dev *pdev, const struct pci_device_id *ent);
@@ -263,13 +328,29 @@ static void nv_adma_host_stop(struct ata_host *host);
 static void nv_adma_post_internal_cmd(struct ata_queued_cmd *qc);
 static void nv_adma_tf_read(struct ata_port *ap, struct ata_taskfile *tf);
 
+static void nv_mcp55_thaw(struct ata_port *ap);
+static void nv_mcp55_freeze(struct ata_port *ap);
+static void nv_swncq_error_handler(struct ata_port *ap);
+static int nv_swncq_slave_config(struct scsi_device *sdev);
+static int nv_swncq_port_start(struct ata_port *ap);
+static void nv_swncq_qc_prep(struct ata_queued_cmd *qc);
+static void nv_swncq_fill_sg(struct ata_queued_cmd *qc);
+static unsigned int nv_swncq_qc_issue(struct ata_queued_cmd *qc);
+static void nv_swncq_irq_clear(struct ata_port *ap, u16 fis);
+static irqreturn_t nv_swncq_interrupt(int irq, void *dev_instance);
+#ifdef CONFIG_PM
+static int nv_swncq_port_suspend(struct ata_port *ap, pm_message_t mesg);
+static int nv_swncq_port_resume(struct ata_port *ap);
+#endif
+
 enum nv_host_type
 {
        GENERIC,
        NFORCE2,
        NFORCE3 = NFORCE2,      /* NF2 == NF3 as far as sata_nv is concerned */
        CK804,
-       ADMA
+       ADMA,
+       SWNCQ,
 };
 
 static const struct pci_device_id nv_pci_tbl[] = {
@@ -280,13 +361,13 @@ static const struct pci_device_id nv_pci_tbl[] = {
        { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_CK804_SATA2), CK804 },
        { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP04_SATA), CK804 },
        { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP04_SATA2), CK804 },
-       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SATA), GENERIC },
-       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SATA2), GENERIC },
-       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SATA), GENERIC },
-       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SATA2), GENERIC },
-       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SATA), GENERIC },
-       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SATA2), GENERIC },
-       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SATA3), GENERIC },
+       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SATA), SWNCQ },
+       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SATA2), SWNCQ },
+       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SATA), SWNCQ },
+       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SATA2), SWNCQ },
+       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SATA), SWNCQ },
+       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SATA2), SWNCQ },
+       { PCI_VDEVICE(NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SATA3), SWNCQ },
 
        { } /* terminate list */
 };
@@ -339,6 +420,25 @@ static struct scsi_host_template nv_adma_sht = {
        .bios_param             = ata_std_bios_param,
 };
 
+static struct scsi_host_template nv_swncq_sht = {
+       .module                 = THIS_MODULE,
+       .name                   = DRV_NAME,
+       .ioctl                  = ata_scsi_ioctl,
+       .queuecommand           = ata_scsi_queuecmd,
+       .change_queue_depth     = ata_scsi_change_queue_depth,
+       .can_queue              = ATA_MAX_QUEUE,
+       .this_id                = ATA_SHT_THIS_ID,
+       .sg_tablesize           = LIBATA_MAX_PRD,
+       .cmd_per_lun            = ATA_SHT_CMD_PER_LUN,
+       .emulated               = ATA_SHT_EMULATED,
+       .use_clustering         = ATA_SHT_USE_CLUSTERING,
+       .proc_name              = DRV_NAME,
+       .dma_boundary           = ATA_DMA_BOUNDARY,
+       .slave_configure        = nv_swncq_slave_config,
+       .slave_destroy          = ata_scsi_slave_destroy,
+       .bios_param             = ata_std_bios_param,
+};
+
 static const struct ata_port_operations nv_generic_ops = {
        .tf_load                = ata_tf_load,
        .tf_read                = ata_tf_read,
@@ -444,6 +544,35 @@ static const struct ata_port_operations nv_adma_ops = {
        .host_stop              = nv_adma_host_stop,
 };
 
+static const struct ata_port_operations nv_swncq_ops = {
+       .tf_load                = ata_tf_load,
+       .tf_read                = ata_tf_read,
+       .exec_command           = ata_exec_command,
+       .check_status           = ata_check_status,
+       .dev_select             = ata_std_dev_select,
+       .bmdma_setup            = ata_bmdma_setup,
+       .bmdma_start            = ata_bmdma_start,
+       .bmdma_stop             = ata_bmdma_stop,
+       .bmdma_status           = ata_bmdma_status,
+       .qc_defer               = ata_std_qc_defer,
+       .qc_prep                = nv_swncq_qc_prep,
+       .qc_issue               = nv_swncq_qc_issue,
+       .freeze                 = nv_mcp55_freeze,
+       .thaw                   = nv_mcp55_thaw,
+       .error_handler          = nv_swncq_error_handler,
+       .post_internal_cmd      = ata_bmdma_post_internal_cmd,
+       .data_xfer              = ata_data_xfer,
+       .irq_clear              = ata_bmdma_irq_clear,
+       .irq_on                 = ata_irq_on,
+       .scr_read               = nv_scr_read,
+       .scr_write              = nv_scr_write,
+#ifdef CONFIG_PM
+       .port_suspend           = nv_swncq_port_suspend,
+       .port_resume            = nv_swncq_port_resume,
+#endif
+       .port_start             = nv_swncq_port_start,
+};
+
 static const struct ata_port_info nv_port_info[] = {
        /* generic */
        {
@@ -490,6 +619,18 @@ static const struct ata_port_info nv_port_info[] = {
                .port_ops       = &nv_adma_ops,
                .irq_handler    = nv_adma_interrupt,
        },
+       /* SWNCQ */
+       {
+               .sht            = &nv_swncq_sht,
+               .flags          = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
+                                 ATA_FLAG_NCQ,
+               .link_flags     = ATA_LFLAG_HRST_TO_RESUME,
+               .pio_mask       = NV_PIO_MASK,
+               .mwdma_mask     = NV_MWDMA_MASK,
+               .udma_mask      = NV_UDMA_MASK,
+               .port_ops       = &nv_swncq_ops,
+               .irq_handler    = nv_swncq_interrupt,
+       },
 };
 
 MODULE_AUTHOR("NVIDIA");
@@ -499,6 +640,7 @@ MODULE_DEVICE_TABLE(pci, nv_pci_tbl);
 MODULE_VERSION(DRV_VERSION);
 
 static int adma_enabled = 1;
+static int swncq_enabled;
 
 static void nv_adma_register_mode(struct ata_port *ap)
 {
@@ -1452,6 +1594,34 @@ static void nv_ck804_thaw(struct ata_port *ap)
        writeb(mask, mmio_base + NV_INT_ENABLE_CK804);
 }
 
+static void nv_mcp55_freeze(struct ata_port *ap)
+{
+       void __iomem *mmio_base = ap->host->iomap[NV_MMIO_BAR];
+       int shift = ap->port_no * NV_INT_PORT_SHIFT_MCP55;
+       u32 mask;
+
+       writel(NV_INT_ALL_MCP55 << shift, mmio_base + NV_INT_STATUS_MCP55);
+
+       mask = readl(mmio_base + NV_INT_ENABLE_MCP55);
+       mask &= ~(NV_INT_ALL_MCP55 << shift);
+       writel(mask, mmio_base + NV_INT_ENABLE_MCP55);
+       ata_bmdma_freeze(ap);
+}
+
+static void nv_mcp55_thaw(struct ata_port *ap)
+{
+       void __iomem *mmio_base = ap->host->iomap[NV_MMIO_BAR];
+       int shift = ap->port_no * NV_INT_PORT_SHIFT_MCP55;
+       u32 mask;
+
+       writel(NV_INT_ALL_MCP55 << shift, mmio_base + NV_INT_STATUS_MCP55);
+
+       mask = readl(mmio_base + NV_INT_ENABLE_MCP55);
+       mask |= (NV_INT_MASK_MCP55 << shift);
+       writel(mask, mmio_base + NV_INT_ENABLE_MCP55);
+       ata_bmdma_thaw(ap);
+}
+
 static int nv_hardreset(struct ata_link *link, unsigned int *class,
                        unsigned long deadline)
 {
@@ -1525,6 +1695,663 @@ static void nv_adma_error_handler(struct ata_port *ap)
                           nv_hardreset, ata_std_postreset);
 }
 
+static void nv_swncq_qc_to_dq(struct ata_port *ap, struct ata_queued_cmd *qc)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       struct defer_queue *dq = &pp->defer_queue;
+
+       /* queue is full */
+       WARN_ON(dq->tail - dq->head == ATA_MAX_QUEUE);
+       dq->defer_bits |= (1 << qc->tag);
+       dq->tag[dq->tail++ & (ATA_MAX_QUEUE - 1)] = qc->tag;
+}
+
+static struct ata_queued_cmd *nv_swncq_qc_from_dq(struct ata_port *ap)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       struct defer_queue *dq = &pp->defer_queue;
+       unsigned int tag;
+
+       if (dq->head == dq->tail)       /* null queue */
+               return NULL;
+
+       tag = dq->tag[dq->head & (ATA_MAX_QUEUE - 1)];
+       dq->tag[dq->head++ & (ATA_MAX_QUEUE - 1)] = ATA_TAG_POISON;
+       WARN_ON(!(dq->defer_bits & (1 << tag)));
+       dq->defer_bits &= ~(1 << tag);
+
+       return ata_qc_from_tag(ap, tag);
+}
+
+static void nv_swncq_fis_reinit(struct ata_port *ap)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+
+       pp->dhfis_bits = 0;
+       pp->dmafis_bits = 0;
+       pp->sdbfis_bits = 0;
+       pp->ncq_flags = 0;
+}
+
+static void nv_swncq_pp_reinit(struct ata_port *ap)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       struct defer_queue *dq = &pp->defer_queue;
+
+       dq->head = 0;
+       dq->tail = 0;
+       dq->defer_bits = 0;
+       pp->qc_active = 0;
+       pp->last_issue_tag = ATA_TAG_POISON;
+       nv_swncq_fis_reinit(ap);
+}
+
+static void nv_swncq_irq_clear(struct ata_port *ap, u16 fis)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+
+       writew(fis, pp->irq_block);
+}
+
+static void __ata_bmdma_stop(struct ata_port *ap)
+{
+       struct ata_queued_cmd qc;
+
+       qc.ap = ap;
+       ata_bmdma_stop(&qc);
+}
+
+static void nv_swncq_ncq_stop(struct ata_port *ap)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       unsigned int i;
+       u32 sactive;
+       u32 done_mask;
+
+       ata_port_printk(ap, KERN_ERR,
+                       "EH in SWNCQ mode,QC:qc_active 0x%X sactive 0x%X\n",
+                       ap->qc_active, ap->link.sactive);
+       ata_port_printk(ap, KERN_ERR,
+               "SWNCQ:qc_active 0x%X defer_bits 0x%X last_issue_tag 0x%x\n  "
+               "dhfis 0x%X dmafis 0x%X sdbfis 0x%X\n",
+               pp->qc_active, pp->defer_queue.defer_bits, pp->last_issue_tag,
+               pp->dhfis_bits, pp->dmafis_bits, pp->sdbfis_bits);
+
+       ata_port_printk(ap, KERN_ERR, "ATA_REG 0x%X ERR_REG 0x%X\n",
+                       ap->ops->check_status(ap),
+                       ioread8(ap->ioaddr.error_addr));
+
+       sactive = readl(pp->sactive_block);
+       done_mask = pp->qc_active ^ sactive;
+
+       ata_port_printk(ap, KERN_ERR, "tag : dhfis dmafis sdbfis sacitve\n");
+       for (i = 0; i < ATA_MAX_QUEUE; i++) {
+               u8 err = 0;
+               if (pp->qc_active & (1 << i))
+                       err = 0;
+               else if (done_mask & (1 << i))
+                       err = 1;
+               else
+                       continue;
+
+               ata_port_printk(ap, KERN_ERR,
+                               "tag 0x%x: %01x %01x %01x %01x %s\n", i,
+                               (pp->dhfis_bits >> i) & 0x1,
+                               (pp->dmafis_bits >> i) & 0x1,
+                               (pp->sdbfis_bits >> i) & 0x1,
+                               (sactive >> i) & 0x1,
+                               (err ? "error! tag doesn't exit" : " "));
+       }
+
+       nv_swncq_pp_reinit(ap);
+       ap->ops->irq_clear(ap);
+       __ata_bmdma_stop(ap);
+       nv_swncq_irq_clear(ap, 0xffff);
+}
+
+static void nv_swncq_error_handler(struct ata_port *ap)
+{
+       struct ata_eh_context *ehc = &ap->link.eh_context;
+
+       if (ap->link.sactive) {
+               nv_swncq_ncq_stop(ap);
+               ehc->i.action |= ATA_EH_HARDRESET;
+       }
+
+       ata_bmdma_drive_eh(ap, ata_std_prereset, ata_std_softreset,
+                          nv_hardreset, ata_std_postreset);
+}
+
+#ifdef CONFIG_PM
+static int nv_swncq_port_suspend(struct ata_port *ap, pm_message_t mesg)
+{
+       void __iomem *mmio = ap->host->iomap[NV_MMIO_BAR];
+       u32 tmp;
+
+       /* clear irq */
+       writel(~0, mmio + NV_INT_STATUS_MCP55);
+
+       /* disable irq */
+       writel(0, mmio + NV_INT_ENABLE_MCP55);
+
+       /* disable swncq */
+       tmp = readl(mmio + NV_CTL_MCP55);
+       tmp &= ~(NV_CTL_PRI_SWNCQ | NV_CTL_SEC_SWNCQ);
+       writel(tmp, mmio + NV_CTL_MCP55);
+
+       return 0;
+}
+
+static int nv_swncq_port_resume(struct ata_port *ap)
+{
+       void __iomem *mmio = ap->host->iomap[NV_MMIO_BAR];
+       u32 tmp;
+
+       /* clear irq */
+       writel(~0, mmio + NV_INT_STATUS_MCP55);
+
+       /* enable irq */
+       writel(0x00fd00fd, mmio + NV_INT_ENABLE_MCP55);
+
+       /* enable swncq */
+       tmp = readl(mmio + NV_CTL_MCP55);
+       writel(tmp | NV_CTL_PRI_SWNCQ | NV_CTL_SEC_SWNCQ, mmio + NV_CTL_MCP55);
+
+       return 0;
+}
+#endif
+
+static void nv_swncq_host_init(struct ata_host *host)
+{
+       u32 tmp;
+       void __iomem *mmio = host->iomap[NV_MMIO_BAR];
+       struct pci_dev *pdev = to_pci_dev(host->dev);
+       u8 regval;
+
+       /* disable  ECO 398 */
+       pci_read_config_byte(pdev, 0x7f, &regval);
+       regval &= ~(1 << 7);
+       pci_write_config_byte(pdev, 0x7f, regval);
+
+       /* enable swncq */
+       tmp = readl(mmio + NV_CTL_MCP55);
+       VPRINTK("HOST_CTL:0x%X\n", tmp);
+       writel(tmp | NV_CTL_PRI_SWNCQ | NV_CTL_SEC_SWNCQ, mmio + NV_CTL_MCP55);
+
+       /* enable irq intr */
+       tmp = readl(mmio + NV_INT_ENABLE_MCP55);
+       VPRINTK("HOST_ENABLE:0x%X\n", tmp);
+       writel(tmp | 0x00fd00fd, mmio + NV_INT_ENABLE_MCP55);
+
+       /*  clear port irq */
+       writel(~0x0, mmio + NV_INT_STATUS_MCP55);
+}
+
+static int nv_swncq_slave_config(struct scsi_device *sdev)
+{
+       struct ata_port *ap = ata_shost_to_port(sdev->host);
+       struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+       struct ata_device *dev;
+       int rc;
+       u8 rev;
+       u8 check_maxtor = 0;
+       unsigned char model_num[ATA_ID_PROD_LEN + 1];
+
+       rc = ata_scsi_slave_config(sdev);
+       if (sdev->id >= ATA_MAX_DEVICES || sdev->channel || sdev->lun)
+               /* Not a proper libata device, ignore */
+               return rc;
+
+       dev = &ap->link.device[sdev->id];
+       if (!(ap->flags & ATA_FLAG_NCQ) || dev->class == ATA_DEV_ATAPI)
+               return rc;
+
+       /* if MCP51 and Maxtor, then disable ncq */
+       if (pdev->device == PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SATA ||
+               pdev->device == PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SATA2)
+               check_maxtor = 1;
+
+       /* if MCP55 and rev <= a2 and Maxtor, then disable ncq */
+       if (pdev->device == PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SATA ||
+               pdev->device == PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SATA2) {
+               pci_read_config_byte(pdev, 0x8, &rev);
+               if (rev <= 0xa2)
+                       check_maxtor = 1;
+       }
+
+       if (!check_maxtor)
+               return rc;
+
+       ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
+
+       if (strncmp(model_num, "Maxtor", 6) == 0) {
+               ata_scsi_change_queue_depth(sdev, 1);
+               ata_dev_printk(dev, KERN_NOTICE,
+                       "Disabling SWNCQ mode (depth %x)\n", sdev->queue_depth);
+       }
+
+       return rc;
+}
+
+static int nv_swncq_port_start(struct ata_port *ap)
+{
+       struct device *dev = ap->host->dev;
+       void __iomem *mmio = ap->host->iomap[NV_MMIO_BAR];
+       struct nv_swncq_port_priv *pp;
+       int rc;
+
+       rc = ata_port_start(ap);
+       if (rc)
+               return rc;
+
+       pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
+       if (!pp)
+               return -ENOMEM;
+
+       pp->prd = dmam_alloc_coherent(dev, ATA_PRD_TBL_SZ * ATA_MAX_QUEUE,
+                                     &pp->prd_dma, GFP_KERNEL);
+       if (!pp->prd)
+               return -ENOMEM;
+       memset(pp->prd, 0, ATA_PRD_TBL_SZ * ATA_MAX_QUEUE);
+
+       ap->private_data = pp;
+       pp->sactive_block = ap->ioaddr.scr_addr + 4 * SCR_ACTIVE;
+       pp->irq_block = mmio + NV_INT_STATUS_MCP55 + ap->port_no * 2;
+       pp->tag_block = mmio + NV_NCQ_REG_MCP55 + ap->port_no * 2;
+
+       return 0;
+}
+
+static void nv_swncq_qc_prep(struct ata_queued_cmd *qc)
+{
+       if (qc->tf.protocol != ATA_PROT_NCQ) {
+               ata_qc_prep(qc);
+               return;
+       }
+
+       if (!(qc->flags & ATA_QCFLAG_DMAMAP))
+               return;
+
+       nv_swncq_fill_sg(qc);
+}
+
+static void nv_swncq_fill_sg(struct ata_queued_cmd *qc)
+{
+       struct ata_port *ap = qc->ap;
+       struct scatterlist *sg;
+       unsigned int idx;
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       struct ata_prd *prd;
+
+       WARN_ON(qc->__sg == NULL);
+       WARN_ON(qc->n_elem == 0 && qc->pad_len == 0);
+
+       prd = pp->prd + ATA_MAX_PRD * qc->tag;
+
+       idx = 0;
+       ata_for_each_sg(sg, qc) {
+               u32 addr, offset;
+               u32 sg_len, len;
+
+               addr = (u32)sg_dma_address(sg);
+               sg_len = sg_dma_len(sg);
+
+               while (sg_len) {
+                       offset = addr & 0xffff;
+                       len = sg_len;
+                       if ((offset + sg_len) > 0x10000)
+                               len = 0x10000 - offset;
+
+                       prd[idx].addr = cpu_to_le32(addr);
+                       prd[idx].flags_len = cpu_to_le32(len & 0xffff);
+
+                       idx++;
+                       sg_len -= len;
+                       addr += len;
+               }
+       }
+
+       if (idx)
+               prd[idx - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
+}
+
+static unsigned int nv_swncq_issue_atacmd(struct ata_port *ap,
+                                         struct ata_queued_cmd *qc)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+
+       if (qc == NULL)
+               return 0;
+
+       DPRINTK("Enter\n");
+
+       writel((1 << qc->tag), pp->sactive_block);
+       pp->last_issue_tag = qc->tag;
+       pp->dhfis_bits &= ~(1 << qc->tag);
+       pp->dmafis_bits &= ~(1 << qc->tag);
+       pp->qc_active |= (0x1 << qc->tag);
+
+       ap->ops->tf_load(ap, &qc->tf);   /* load tf registers */
+       ap->ops->exec_command(ap, &qc->tf);
+
+       DPRINTK("Issued tag %u\n", qc->tag);
+
+       return 0;
+}
+
+static unsigned int nv_swncq_qc_issue(struct ata_queued_cmd *qc)
+{
+       struct ata_port *ap = qc->ap;
+       struct nv_swncq_port_priv *pp = ap->private_data;
+
+       if (qc->tf.protocol != ATA_PROT_NCQ)
+               return ata_qc_issue_prot(qc);
+
+       DPRINTK("Enter\n");
+
+       if (!pp->qc_active)
+               nv_swncq_issue_atacmd(ap, qc);
+       else
+               nv_swncq_qc_to_dq(ap, qc);      /* add qc to defer queue */
+
+       return 0;
+}
+
+static void nv_swncq_hotplug(struct ata_port *ap, u32 fis)
+{
+       u32 serror;
+       struct ata_eh_info *ehi = &ap->link.eh_info;
+
+       ata_ehi_clear_desc(ehi);
+
+       /* AHCI needs SError cleared; otherwise, it might lock up */
+       sata_scr_read(&ap->link, SCR_ERROR, &serror);
+       sata_scr_write(&ap->link, SCR_ERROR, serror);
+
+       /* analyze @irq_stat */
+       if (fis & NV_SWNCQ_IRQ_ADDED)
+               ata_ehi_push_desc(ehi, "hot plug");
+       else if (fis & NV_SWNCQ_IRQ_REMOVED)
+               ata_ehi_push_desc(ehi, "hot unplug");
+
+       ata_ehi_hotplugged(ehi);
+
+       /* okay, let's hand over to EH */
+       ehi->serror |= serror;
+
+       ata_port_freeze(ap);
+}
+
+static int nv_swncq_sdbfis(struct ata_port *ap)
+{
+       struct ata_queued_cmd *qc;
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       struct ata_eh_info *ehi = &ap->link.eh_info;
+       u32 sactive;
+       int nr_done = 0;
+       u32 done_mask;
+       int i;
+       u8 host_stat;
+       u8 lack_dhfis = 0;
+
+       host_stat = ap->ops->bmdma_status(ap);
+       if (unlikely(host_stat & ATA_DMA_ERR)) {
+               /* error when transfering data to/from memory */
+               ata_ehi_clear_desc(ehi);
+               ata_ehi_push_desc(ehi, "BMDMA stat 0x%x", host_stat);
+               ehi->err_mask |= AC_ERR_HOST_BUS;
+               ehi->action |= ATA_EH_SOFTRESET;
+               return -EINVAL;
+       }
+
+       ap->ops->irq_clear(ap);
+       __ata_bmdma_stop(ap);
+
+       sactive = readl(pp->sactive_block);
+       done_mask = pp->qc_active ^ sactive;
+
+       if (unlikely(done_mask & sactive)) {
+               ata_ehi_clear_desc(ehi);
+               ata_ehi_push_desc(ehi, "illegal SWNCQ:qc_active transition"
+                                 "(%08x->%08x)", pp->qc_active, sactive);
+               ehi->err_mask |= AC_ERR_HSM;
+               ehi->action |= ATA_EH_HARDRESET;
+               return -EINVAL;
+       }
+       for (i = 0; i < ATA_MAX_QUEUE; i++) {
+               if (!(done_mask & (1 << i)))
+                       continue;
+
+               qc = ata_qc_from_tag(ap, i);
+               if (qc) {
+                       ata_qc_complete(qc);
+                       pp->qc_active &= ~(1 << i);
+                       pp->dhfis_bits &= ~(1 << i);
+                       pp->dmafis_bits &= ~(1 << i);
+                       pp->sdbfis_bits |= (1 << i);
+                       nr_done++;
+               }
+       }
+
+       if (!ap->qc_active) {
+               DPRINTK("over\n");
+               nv_swncq_pp_reinit(ap);
+               return nr_done;
+       }
+
+       if (pp->qc_active & pp->dhfis_bits)
+               return nr_done;
+
+       if ((pp->ncq_flags & ncq_saw_backout) ||
+           (pp->qc_active ^ pp->dhfis_bits))
+               /* if the controller cann't get a device to host register FIS,
+                * The driver needs to reissue the new command.
+                */
+               lack_dhfis = 1;
+
+       DPRINTK("id 0x%x QC: qc_active 0x%x,"
+               "SWNCQ:qc_active 0x%X defer_bits %X "
+               "dhfis 0x%X dmafis 0x%X last_issue_tag %x\n",
+               ap->print_id, ap->qc_active, pp->qc_active,
+               pp->defer_queue.defer_bits, pp->dhfis_bits,
+               pp->dmafis_bits, pp->last_issue_tag);
+
+       nv_swncq_fis_reinit(ap);
+
+       if (lack_dhfis) {
+               qc = ata_qc_from_tag(ap, pp->last_issue_tag);
+               nv_swncq_issue_atacmd(ap, qc);
+               return nr_done;
+       }
+
+       if (pp->defer_queue.defer_bits) {
+               /* send deferral queue command */
+               qc = nv_swncq_qc_from_dq(ap);
+               WARN_ON(qc == NULL);
+               nv_swncq_issue_atacmd(ap, qc);
+       }
+
+       return nr_done;
+}
+
+static inline u32 nv_swncq_tag(struct ata_port *ap)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       u32 tag;
+
+       tag = readb(pp->tag_block) >> 2;
+       return (tag & 0x1f);
+}
+
+static int nv_swncq_dmafis(struct ata_port *ap)
+{
+       struct ata_queued_cmd *qc;
+       unsigned int rw;
+       u8 dmactl;
+       u32 tag;
+       struct nv_swncq_port_priv *pp = ap->private_data;
+
+       __ata_bmdma_stop(ap);
+       tag = nv_swncq_tag(ap);
+
+       DPRINTK("dma setup tag 0x%x\n", tag);
+       qc = ata_qc_from_tag(ap, tag);
+
+       if (unlikely(!qc))
+               return 0;
+
+       rw = qc->tf.flags & ATA_TFLAG_WRITE;
+
+       /* load PRD table addr. */
+       iowrite32(pp->prd_dma + ATA_PRD_TBL_SZ * qc->tag,
+                 ap->ioaddr.bmdma_addr + ATA_DMA_TABLE_OFS);
+
+       /* specify data direction, triple-check start bit is clear */
+       dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
+       dmactl &= ~ATA_DMA_WR;
+       if (!rw)
+               dmactl |= ATA_DMA_WR;
+
+       iowrite8(dmactl | ATA_DMA_START, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
+
+       return 1;
+}
+
+static void nv_swncq_host_interrupt(struct ata_port *ap, u16 fis)
+{
+       struct nv_swncq_port_priv *pp = ap->private_data;
+       struct ata_queued_cmd *qc;
+       struct ata_eh_info *ehi = &ap->link.eh_info;
+       u32 serror;
+       u8 ata_stat;
+       int rc = 0;
+
+       ata_stat = ap->ops->check_status(ap);
+       nv_swncq_irq_clear(ap, fis);
+       if (!fis)
+               return;
+
+       if (ap->pflags & ATA_PFLAG_FROZEN)
+               return;
+
+       if (fis & NV_SWNCQ_IRQ_HOTPLUG) {
+               nv_swncq_hotplug(ap, fis);
+               return;
+       }
+
+       if (!pp->qc_active)
+               return;
+
+       if (ap->ops->scr_read(ap, SCR_ERROR, &serror))
+               return;
+       ap->ops->scr_write(ap, SCR_ERROR, serror);
+
+       if (ata_stat & ATA_ERR) {
+               ata_ehi_clear_desc(ehi);
+               ata_ehi_push_desc(ehi, "Ata error. fis:0x%X", fis);
+               ehi->err_mask |= AC_ERR_DEV;
+               ehi->serror |= serror;
+               ehi->action |= ATA_EH_SOFTRESET;
+               ata_port_freeze(ap);
+               return;
+       }
+
+       if (fis & NV_SWNCQ_IRQ_BACKOUT) {
+               /* If the IRQ is backout, driver must issue
+                * the new command again some time later.
+                */
+               pp->ncq_flags |= ncq_saw_backout;
+       }
+
+       if (fis & NV_SWNCQ_IRQ_SDBFIS) {
+               pp->ncq_flags |= ncq_saw_sdb;
+               DPRINTK("id 0x%x SWNCQ: qc_active 0x%X "
+                       "dhfis 0x%X dmafis 0x%X sactive 0x%X\n",
+                       ap->print_id, pp->qc_active, pp->dhfis_bits,
+                       pp->dmafis_bits, readl(pp->sactive_block));
+               rc = nv_swncq_sdbfis(ap);
+               if (rc < 0)
+                       goto irq_error;
+       }
+
+       if (fis & NV_SWNCQ_IRQ_DHREGFIS) {
+               /* The interrupt indicates the new command
+                * was transmitted correctly to the drive.
+                */
+               pp->dhfis_bits |= (0x1 << pp->last_issue_tag);
+               pp->ncq_flags |= ncq_saw_d2h;
+               if (pp->ncq_flags & (ncq_saw_sdb | ncq_saw_backout)) {
+                       ata_ehi_push_desc(ehi, "illegal fis transaction");
+                       ehi->err_mask |= AC_ERR_HSM;
+                       ehi->action |= ATA_EH_HARDRESET;
+                       goto irq_error;
+               }
+
+               if (!(fis & NV_SWNCQ_IRQ_DMASETUP) &&
+                   !(pp->ncq_flags & ncq_saw_dmas)) {
+                       ata_stat = ap->ops->check_status(ap);
+                       if (ata_stat & ATA_BUSY)
+                               goto irq_exit;
+
+                       if (pp->defer_queue.defer_bits) {
+                               DPRINTK("send next command\n");
+                               qc = nv_swncq_qc_from_dq(ap);
+                               nv_swncq_issue_atacmd(ap, qc);
+                       }
+               }
+       }
+
+       if (fis & NV_SWNCQ_IRQ_DMASETUP) {
+               /* program the dma controller with appropriate PRD buffers
+                * and start the DMA transfer for requested command.
+                */
+               pp->dmafis_bits |= (0x1 << nv_swncq_tag(ap));
+               pp->ncq_flags |= ncq_saw_dmas;
+               rc = nv_swncq_dmafis(ap);
+       }
+
+irq_exit:
+       return;
+irq_error:
+       ata_ehi_push_desc(ehi, "fis:0x%x", fis);
+       ata_port_freeze(ap);
+       return;
+}
+
+static irqreturn_t nv_swncq_interrupt(int irq, void *dev_instance)
+{
+       struct ata_host *host = dev_instance;
+       unsigned int i;
+       unsigned int handled = 0;
+       unsigned long flags;
+       u32 irq_stat;
+
+       spin_lock_irqsave(&host->lock, flags);
+
+       irq_stat = readl(host->iomap[NV_MMIO_BAR] + NV_INT_STATUS_MCP55);
+
+       for (i = 0; i < host->n_ports; i++) {
+               struct ata_port *ap = host->ports[i];
+
+               if (ap && !(ap->flags & ATA_FLAG_DISABLED)) {
+                       if (ap->link.sactive) {
+                               nv_swncq_host_interrupt(ap, (u16)irq_stat);
+                               handled = 1;
+                       } else {
+                               if (irq_stat)   /* reserve Hotplug */
+                                       nv_swncq_irq_clear(ap, 0xfff0);
+
+                               handled += nv_host_intr(ap, (u8)irq_stat);
+                       }
+               }
+               irq_stat >>= NV_INT_PORT_SHIFT_MCP55;
+       }
+
+       spin_unlock_irqrestore(&host->lock, flags);
+
+       return IRQ_RETVAL(handled);
+}
+
 static int nv_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
 {
        static int printed_version = 0;
@@ -1551,7 +2378,7 @@ static int nv_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
                return rc;
 
        /* determine type and allocate host */
-       if (type >= CK804 && adma_enabled) {
+       if (type == CK804 && adma_enabled) {
                dev_printk(KERN_NOTICE, &pdev->dev, "Using ADMA mode\n");
                type = ADMA;
        }
@@ -1597,6 +2424,9 @@ static int nv_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
                rc = nv_adma_host_init(host);
                if (rc)
                        return rc;
+       } else if (type == SWNCQ && swncq_enabled) {
+               dev_printk(KERN_NOTICE, &pdev->dev, "Using SWNCQ mode\n");
+               nv_swncq_host_init(host);
        }
 
        pci_set_master(pdev);
@@ -1696,3 +2526,6 @@ module_init(nv_init);
 module_exit(nv_exit);
 module_param_named(adma, adma_enabled, bool, 0444);
 MODULE_PARM_DESC(adma, "Enable use of ADMA (Default: true)");
+module_param_named(swncq, swncq_enabled, bool, 0444);
+MODULE_PARM_DESC(swncq, "Enable use of SWNCQ (Default: false)");
+