sata_mv: optimize use of mv_edma_cfg

Try and avoid unnecessary reconfiguration of the EDMA config register
on every single non-EDMA I/O operation, by moving the call to
mv_edma_cfg() into mv_stop_edma().  It must then also be invoked
from mv_hardreset() and from mv_port_start().

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index 6f8a49bc4521..8f356e4417d2 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -979,6 +979,7 @@ static int mv_stop_edma(struct ata_port *ap)
 {
         void __iomem *port_mmio = mv_ap_base(ap);
         struct mv_port_priv *pp = ap->private_data;
+        int err = 0;
 
         if (!(pp->pp_flags & MV_PP_FLAG_EDMA_EN))
                 return 0;
@@ -986,9 +987,10 @@ static int mv_stop_edma(struct ata_port *ap)
         mv_wait_for_edma_empty_idle(ap);
         if (mv_stop_edma_engine(port_mmio)) {
                 ata_port_printk(ap, KERN_ERR, "Unable to stop eDMA\n");
-                return -EIO;
+                err = -EIO;
         }
-        return 0;
+        mv_edma_cfg(ap, 0, 0);
+        return err;
 }
 
 #ifdef ATA_DEBUG
@@ -1337,6 +1339,7 @@ static int mv_port_start(struct ata_port *ap)
                         pp->sg_tbl_dma[tag] = pp->sg_tbl_dma[0];
                 }
         }
+        mv_edma_cfg(ap, 0, 0);
         return 0;
 
 out_port_free_dma_mem:
@@ -1797,7 +1800,6 @@ static unsigned int mv_qc_issue(struct ata_queued_cmd *qc)
                  * shadow block, etc registers.
                  */
                 mv_stop_edma(ap);
-                mv_edma_cfg(ap, 0, 0);
                 mv_clear_and_enable_port_irqs(ap, mv_ap_base(ap), port_irqs);
                 mv_pmp_select(ap, qc->dev->link->pmp);
                 return ata_sff_qc_issue(qc);
@@ -2997,6 +2999,7 @@ static int mv_hardreset(struct ata_link *link, unsigned int *class,
                                 extra = HZ; /* only extend it once, max */
                 }
         } while (sstatus != 0x0 && sstatus != 0x113 && sstatus != 0x123);
+        mv_edma_cfg(ap, 0, 0);
 
         return rc;
 }