enic: reduce ioread in devcmd2

posted_index is RO in firmware. We need not do ioread everytime to get
posted index. Store posted index locally.

Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/cisco/enic/vnic_dev.c b/drivers/net/ethernet/cisco/enic/vnic_dev.c
index 19a49a6..a3badef 100644 (file)
--- a/drivers/net/ethernet/cisco/enic/vnic_dev.c
+++ b/drivers/net/ethernet/cisco/enic/vnic_dev.c
@@ -301,12 +301,12 @@ static int _vnic_dev_cmd2(struct vnic_dev *vdev, enum vnic_devcmd_cmd cmd,
        struct devcmd2_result *result = dc2c->result + dc2c->next_result;
        unsigned int i;
        int delay, err;
-       u32 fetch_index, posted, new_posted;
+       u32 fetch_index, new_posted;
+       u32 posted = dc2c->posted;
 
-       posted = ioread32(&dc2c->wq_ctrl->posted_index);
        fetch_index = ioread32(&dc2c->wq_ctrl->fetch_index);
 
-       if (posted == 0xFFFFFFFF || fetch_index == 0xFFFFFFFF)
+       if (fetch_index == 0xFFFFFFFF)
                return -ENODEV;
 
        new_posted = (posted + 1) % DEVCMD2_RING_SIZE;
@@ -331,6 +331,7 @@ static int _vnic_dev_cmd2(struct vnic_dev *vdev, enum vnic_devcmd_cmd cmd,
         */
        wmb();
        iowrite32(new_posted, &dc2c->wq_ctrl->posted_index);
+       dc2c->posted = new_posted;
 
        if (dc2c->cmd_ring[posted].flags & DEVCMD2_FNORESULT)
                return 0;
@@ -402,6 +403,7 @@ static int vnic_dev_init_devcmd2(struct vnic_dev *vdev)
 
        enic_wq_init_start(&vdev->devcmd2->wq, 0, fetch_index, fetch_index, 0,
                           0);
+       vdev->devcmd2->posted = fetch_index;
        vnic_wq_enable(&vdev->devcmd2->wq);
 
        err = vnic_dev_alloc_desc_ring(vdev, &vdev->devcmd2->results_ring,

diff --git a/drivers/net/ethernet/cisco/enic/vnic_wq.h b/drivers/net/ethernet/cisco/enic/vnic_wq.h
index 8944af9..0120961 100644 (file)
--- a/drivers/net/ethernet/cisco/enic/vnic_wq.h
+++ b/drivers/net/ethernet/cisco/enic/vnic_wq.h
@@ -97,6 +97,7 @@ struct devcmd2_controller {
        int color;
        struct vnic_dev_ring results_ring;
        struct vnic_wq wq;
+       u32 posted;
 };
 
 static inline unsigned int vnic_wq_desc_avail(struct vnic_wq *wq)