sata_fsl,mv,nv: prepare for NCQ command completion update

Make the following changes to prepare for NCQ command completion
update.  Changes made by this patch don't cause any functional
difference.

* sata_fsl_host_intr(): rename the local variable qc_active to
  done_mask as that's what it is.

* mv_process_crpb_response(): restructure if clause for easier update.

* nv_adma_interrupt(): drop unnecessary error variable.

* nv_swncq_sdbfis(): drop unnecessary nr_done and return 0 on success.
  Typo fix.

* nv_swncq_dmafis(): drop unused return value and return void.

* nv_swncq_host_interrupt(): drop unnecessary return value handling.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ashish Kalra <ashish.kalra@freescale.com>
Cc: Saeed Bishara <saeed@marvell.com>
Cc: Mark Lord <liml@rtr.ca>
Cc: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

3 files changed, 48 insertions, 51 deletions

diff --git a/drivers/ata/sata_fsl.c b/drivers/ata/sata_fsl.c
index 61c89b54ea23..18c986dbb7f1 100644
--- a/drivers/ata/sata_fsl.c
+++ b/drivers/ata/sata_fsl.c
@@ -1096,7 +1096,7 @@ static void sata_fsl_host_intr(struct ata_port *ap)
 {
         struct sata_fsl_host_priv *host_priv = ap->host->private_data;
         void __iomem *hcr_base = host_priv->hcr_base;
-        u32 hstatus, qc_active = 0;
+        u32 hstatus, done_mask = 0;
         struct ata_queued_cmd *qc;
         u32 SError;
 
@@ -1116,28 +1116,28 @@ static void sata_fsl_host_intr(struct ata_port *ap)
         }
 
         /* Read command completed register */
-        qc_active = ioread32(hcr_base + CC);
+        done_mask = ioread32(hcr_base + CC);
 
         VPRINTK("Status of all queues :\n");
-        VPRINTK("qc_active/CC = 0x%x, CA = 0x%x, CE=0x%x,CQ=0x%x,apqa=0x%x\n",
-                qc_active,
+        VPRINTK("done_mask/CC = 0x%x, CA = 0x%x, CE=0x%x,CQ=0x%x,apqa=0x%x\n",
+                done_mask,
                 ioread32(hcr_base + CA),
                 ioread32(hcr_base + CE),
                 ioread32(hcr_base + CQ),
                 ap->qc_active);
 
-        if (qc_active & ap->qc_active) {
+        if (done_mask & ap->qc_active) {
                 int i;
                 /* clear CC bit, this will also complete the interrupt */
-                iowrite32(qc_active, hcr_base + CC);
+                iowrite32(done_mask, hcr_base + CC);
 
                 DPRINTK("Status of all queues :\n");
-                DPRINTK("qc_active/CC = 0x%x, CA = 0x%x, CE=0x%x\n",
-                        qc_active, ioread32(hcr_base + CA),
+                DPRINTK("done_mask/CC = 0x%x, CA = 0x%x, CE=0x%x\n",
+                        done_mask, ioread32(hcr_base + CA),
                         ioread32(hcr_base + CE));
 
                 for (i = 0; i < SATA_FSL_QUEUE_DEPTH; i++) {
-                        if (qc_active & (1 << i)) {
+                        if (done_mask & (1 << i)) {
                                 qc = ata_qc_from_tag(ap, i);
                                 if (qc) {
                                         ata_qc_complete(qc);
@@ -1164,7 +1164,7 @@ static void sata_fsl_host_intr(struct ata_port *ap)
                 /* Spurious Interrupt!! */
                 DPRINTK("spurious interrupt!!, CC = 0x%x\n",
                         ioread32(hcr_base + CC));
-                iowrite32(qc_active, hcr_base + CC);
+                iowrite32(done_mask, hcr_base + CC);
                 return;
         }
 }
diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index a476cd99b95d..9463c71dd38e 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -2716,34 +2716,35 @@ static void mv_err_intr(struct ata_port *ap)
 static void mv_process_crpb_response(struct ata_port *ap,
                 struct mv_crpb *response, unsigned int tag, int ncq_enabled)
 {
+        u8 ata_status;
+        u16 edma_status = le16_to_cpu(response->flags);
         struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
 
-        if (qc) {
-                u8 ata_status;
-                u16 edma_status = le16_to_cpu(response->flags);
-                /*
-                 * edma_status from a response queue entry:
-                 *   LSB is from EDMA_ERR_IRQ_CAUSE (non-NCQ only).
-                 *   MSB is saved ATA status from command completion.
-                 */
-                if (!ncq_enabled) {
-                        u8 err_cause = edma_status & 0xff & ~EDMA_ERR_DEV;
-                        if (err_cause) {
-                                /*
-                                 * Error will be seen/handled by mv_err_intr().
-                                 * So do nothing at all here.
-                                 */
-                                return;
-                        }
-                }
-                ata_status = edma_status >> CRPB_FLAG_STATUS_SHIFT;
-                if (!ac_err_mask(ata_status))
-                        ata_qc_complete(qc);
-                /* else: leave it for mv_err_intr() */
-        } else {
+        if (unlikely(!qc)) {
                 ata_port_printk(ap, KERN_ERR, "%s: no qc for tag=%d\n",
                                 __func__, tag);
+                return;
+        }
+
+        /*
+         * edma_status from a response queue entry:
+         *   LSB is from EDMA_ERR_IRQ_CAUSE (non-NCQ only).
+         *   MSB is saved ATA status from command completion.
+         */
+        if (!ncq_enabled) {
+                u8 err_cause = edma_status & 0xff & ~EDMA_ERR_DEV;
+                if (err_cause) {
+                        /*
+                         * Error will be seen/handled by
+                         * mv_err_intr().  So do nothing at all here.
+                         */
+                        return;
+                }
         }
+        ata_status = edma_status >> CRPB_FLAG_STATUS_SHIFT;
+        if (!ac_err_mask(ata_status))
+                ata_qc_complete(qc);
+        /* else: leave it for mv_err_intr() */
 }
 
 static void mv_process_crpb_entries(struct ata_port *ap, struct mv_port_priv *pp)
diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
index 21161136cad0..cb89ef8d99d9 100644
--- a/drivers/ata/sata_nv.c
+++ b/drivers/ata/sata_nv.c
@@ -1018,7 +1018,7 @@ static irqreturn_t nv_adma_interrupt(int irq, void *dev_instance)
                               NV_ADMA_STAT_CPBERR |
                               NV_ADMA_STAT_CMD_COMPLETE)) {
                         u32 check_commands = notifier_clears[i];
-                        int pos, error = 0;
+                        int pos, rc;
 
                         if (status & NV_ADMA_STAT_CPBERR) {
                                 /* check all active commands */
@@ -1030,10 +1030,12 @@ static irqreturn_t nv_adma_interrupt(int irq, void *dev_instance)
                         }
 
                         /* check CPBs for completed commands */
-                        while ((pos = ffs(check_commands)) && !error) {
+                        while ((pos = ffs(check_commands))) {
                                 pos--;
-                                error = nv_adma_check_cpb(ap, pos,
+                                rc = nv_adma_check_cpb(ap, pos,
                                                 notifier_error & (1 << pos));
+                                if (unlikely(rc))
+                                        check_commands = 0;
                                 check_commands &= ~(1 << pos);
                         }
                 }
@@ -2129,7 +2131,6 @@ static int nv_swncq_sdbfis(struct ata_port *ap)
         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;
@@ -2170,22 +2171,21 @@ static int nv_swncq_sdbfis(struct ata_port *ap)
                         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;
+                return 0;
         }
 
         if (pp->qc_active & pp->dhfis_bits)
-                return nr_done;
+                return 0;
 
         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,
+                /* if the controller can't get a device to host register FIS,
                  * The driver needs to reissue the new command.
                  */
                 lack_dhfis = 1;
@@ -2202,7 +2202,7 @@ static int nv_swncq_sdbfis(struct ata_port *ap)
         if (lack_dhfis) {
                 qc = ata_qc_from_tag(ap, pp->last_issue_tag);
                 nv_swncq_issue_atacmd(ap, qc);
-                return nr_done;
+                return 0;
         }
 
         if (pp->defer_queue.defer_bits) {
@@ -2212,7 +2212,7 @@ static int nv_swncq_sdbfis(struct ata_port *ap)
                 nv_swncq_issue_atacmd(ap, qc);
         }
 
-        return nr_done;
+        return 0;
 }
 
 static inline u32 nv_swncq_tag(struct ata_port *ap)
@@ -2224,7 +2224,7 @@ static inline u32 nv_swncq_tag(struct ata_port *ap)
         return (tag & 0x1f);
 }
 
-static int nv_swncq_dmafis(struct ata_port *ap)
+static void nv_swncq_dmafis(struct ata_port *ap)
 {
         struct ata_queued_cmd *qc;
         unsigned int rw;
@@ -2239,7 +2239,7 @@ static int nv_swncq_dmafis(struct ata_port *ap)
         qc = ata_qc_from_tag(ap, tag);
 
         if (unlikely(!qc))
-                return 0;
+                return;
 
         rw = qc->tf.flags & ATA_TFLAG_WRITE;
 
@@ -2254,8 +2254,6 @@ static int nv_swncq_dmafis(struct ata_port *ap)
                 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)
@@ -2265,7 +2263,6 @@ static void nv_swncq_host_interrupt(struct ata_port *ap, u16 fis)
         struct ata_eh_info *ehi = &ap->link.eh_info;
         u32 serror;
         u8 ata_stat;
-        int rc = 0;
 
         ata_stat = ap->ops->sff_check_status(ap);
         nv_swncq_irq_clear(ap, fis);
@@ -2310,8 +2307,7 @@ static void nv_swncq_host_interrupt(struct ata_port *ap, u16 fis)
                         "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)
+                if (nv_swncq_sdbfis(ap) < 0)
                         goto irq_error;
         }
 
@@ -2348,7 +2344,7 @@ static void nv_swncq_host_interrupt(struct ata_port *ap, u16 fis)
                  */
                 pp->dmafis_bits |= (0x1 << nv_swncq_tag(ap));
                 pp->ncq_flags |= ncq_saw_dmas;
-                rc = nv_swncq_dmafis(ap);
+                nv_swncq_dmafis(ap);
         }
 
 irq_exit: