enic: feature add: add ethtool -c/C support

Only rx_usec and tx_usec options for ethtool -C are settable as those
are the only settings that make sense to HW.  Adds driver reporting of
intr coalescing timer value in usec units rather than HW units.

Signed-off-by: Vasanthy Kolluri <vkolluri@cisco.com>
Signed-off-by: Scott Feldman <scofeldm@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 85 insertions, 7 deletions

diff --git a/drivers/net/enic/enic.h b/drivers/net/enic/enic.h
index b090d65ad0c8..ee01f5a6d0d4 100644
--- a/drivers/net/enic/enic.h
+++ b/drivers/net/enic/enic.h
@@ -93,6 +93,8 @@ struct enic {
         unsigned int mc_count;
         int csum_rx_enabled;
         u32 port_mtu;
+        u32 rx_coalesce_usecs;
+        u32 tx_coalesce_usecs;
 
         /* work queue cache line section */
         ____cacheline_aligned struct vnic_wq wq[ENIC_WQ_MAX];
diff --git a/drivers/net/enic/enic_main.c b/drivers/net/enic/enic_main.c
index 019b1480cc0c..e56f41672b37 100644
--- a/drivers/net/enic/enic_main.c
+++ b/drivers/net/enic/enic_main.c
@@ -261,6 +261,62 @@ static void enic_set_msglevel(struct net_device *netdev, u32 value)
         enic->msg_enable = value;
 }
 
+static int enic_get_coalesce(struct net_device *netdev,
+        struct ethtool_coalesce *ecmd)
+{
+        struct enic *enic = netdev_priv(netdev);
+
+        ecmd->tx_coalesce_usecs = enic->tx_coalesce_usecs;
+        ecmd->rx_coalesce_usecs = enic->rx_coalesce_usecs;
+
+        return 0;
+}
+
+static int enic_set_coalesce(struct net_device *netdev,
+        struct ethtool_coalesce *ecmd)
+{
+        struct enic *enic = netdev_priv(netdev);
+        u32 tx_coalesce_usecs;
+        u32 rx_coalesce_usecs;
+
+        tx_coalesce_usecs = min_t(u32,
+                INTR_COALESCE_HW_TO_USEC(VNIC_INTR_TIMER_MAX),
+                ecmd->tx_coalesce_usecs);
+        rx_coalesce_usecs = min_t(u32,
+                INTR_COALESCE_HW_TO_USEC(VNIC_INTR_TIMER_MAX),
+                ecmd->rx_coalesce_usecs);
+
+        switch (vnic_dev_get_intr_mode(enic->vdev)) {
+        case VNIC_DEV_INTR_MODE_INTX:
+                if (tx_coalesce_usecs != rx_coalesce_usecs)
+                        return -EINVAL;
+
+                vnic_intr_coalescing_timer_set(&enic->intr[ENIC_INTX_WQ_RQ],
+                        INTR_COALESCE_USEC_TO_HW(tx_coalesce_usecs));
+                break;
+        case VNIC_DEV_INTR_MODE_MSI:
+                if (tx_coalesce_usecs != rx_coalesce_usecs)
+                        return -EINVAL;
+
+                vnic_intr_coalescing_timer_set(&enic->intr[0],
+                        INTR_COALESCE_USEC_TO_HW(tx_coalesce_usecs));
+                break;
+        case VNIC_DEV_INTR_MODE_MSIX:
+                vnic_intr_coalescing_timer_set(&enic->intr[ENIC_MSIX_WQ],
+                        INTR_COALESCE_USEC_TO_HW(tx_coalesce_usecs));
+                vnic_intr_coalescing_timer_set(&enic->intr[ENIC_MSIX_RQ],
+                        INTR_COALESCE_USEC_TO_HW(rx_coalesce_usecs));
+                break;
+        default:
+                break;
+        }
+
+        enic->tx_coalesce_usecs = tx_coalesce_usecs;
+        enic->rx_coalesce_usecs = rx_coalesce_usecs;
+
+        return 0;
+}
+
 static const struct ethtool_ops enic_ethtool_ops = {
         .get_settings = enic_get_settings,
         .get_drvinfo = enic_get_drvinfo,
@@ -278,6 +334,8 @@ static const struct ethtool_ops enic_ethtool_ops = {
         .set_sg = ethtool_op_set_sg,
         .get_tso = ethtool_op_get_tso,
         .set_tso = enic_set_tso,
+        .get_coalesce = enic_get_coalesce,
+        .set_coalesce = enic_set_coalesce,
         .get_flags = ethtool_op_get_flags,
         .set_flags = ethtool_op_set_flags,
 };
@@ -363,12 +421,12 @@ static void enic_mtu_check(struct enic *enic)
         u32 mtu = vnic_dev_mtu(enic->vdev);
 
         if (mtu && mtu != enic->port_mtu) {
+                enic->port_mtu = mtu;
                 if (mtu < enic->netdev->mtu)
                         printk(KERN_WARNING PFX
                                 "%s: interface MTU (%d) set higher "
                                 "than switch port MTU (%d)\n",
                                 enic->netdev->name, enic->netdev->mtu, mtu);
-                enic->port_mtu = mtu;
         }
 }
 
@@ -1990,6 +2048,9 @@ static int __devinit enic_probe(struct pci_dev *pdev,
                 goto err_out_dev_deinit;
         }
 
+        enic->tx_coalesce_usecs = enic->config.intr_timer_usec;
+        enic->rx_coalesce_usecs = enic->tx_coalesce_usecs;
+
         netdev->netdev_ops = &enic_netdev_ops;
         netdev->watchdog_timeo = 2 * HZ;
         netdev->ethtool_ops = &enic_ethtool_ops;
diff --git a/drivers/net/enic/enic_res.c b/drivers/net/enic/enic_res.c
index a605da1475c6..02839bf0fe8b 100644
--- a/drivers/net/enic/enic_res.c
+++ b/drivers/net/enic/enic_res.c
@@ -66,9 +66,9 @@ int enic_get_vnic_config(struct enic *enic)
         GET_CONFIG(wq_desc_count);
         GET_CONFIG(rq_desc_count);
         GET_CONFIG(mtu);
-        GET_CONFIG(intr_timer);
         GET_CONFIG(intr_timer_type);
         GET_CONFIG(intr_mode);
+        GET_CONFIG(intr_timer_usec);
 
         c->wq_desc_count =
                 min_t(u32, ENIC_MAX_WQ_DESCS,
@@ -88,15 +88,17 @@ int enic_get_vnic_config(struct enic *enic)
                 max_t(u16, ENIC_MIN_MTU,
                 c->mtu));
 
-        c->intr_timer = min_t(u16, VNIC_INTR_TIMER_MAX, c->intr_timer);
+        c->intr_timer_usec = min_t(u32,
+                INTR_COALESCE_HW_TO_USEC(VNIC_INTR_TIMER_MAX),
+                c->intr_timer_usec);
 
         printk(KERN_INFO PFX "vNIC MAC addr %pM wq/rq %d/%d\n",
                 enic->mac_addr, c->wq_desc_count, c->rq_desc_count);
         printk(KERN_INFO PFX "vNIC mtu %d csum tx/rx %d/%d tso/lro %d/%d "
-                "intr timer %d\n",
+                "intr timer %d usec\n",
                 c->mtu, ENIC_SETTING(enic, TXCSUM),
                 ENIC_SETTING(enic, RXCSUM), ENIC_SETTING(enic, TSO),
-                ENIC_SETTING(enic, LRO), c->intr_timer);
+                ENIC_SETTING(enic, LRO), c->intr_timer_usec);
 
         return 0;
 }
@@ -303,7 +305,7 @@ void enic_init_vnic_resources(struct enic *enic)
 
         for (i = 0; i < enic->intr_count; i++) {
                 vnic_intr_init(&enic->intr[i],
-                        enic->config.intr_timer,
+                        INTR_COALESCE_USEC_TO_HW(enic->config.intr_timer_usec),
                         enic->config.intr_timer_type,
                         mask_on_assertion);
         }
diff --git a/drivers/net/enic/vnic_enet.h b/drivers/net/enic/vnic_enet.h
index 6332ac9391b8..8eeb6758491b 100644
--- a/drivers/net/enic/vnic_enet.h
+++ b/drivers/net/enic/vnic_enet.h
@@ -20,6 +20,10 @@
 #ifndef _VNIC_ENIC_H_
 #define _VNIC_ENIC_H_
 
+/* Hardware intr coalesce timer is in units of 1.5us */
+#define INTR_COALESCE_USEC_TO_HW(usec) ((usec) * 2/3)
+#define INTR_COALESCE_HW_TO_USEC(usec) ((usec) * 3/2)
+
 /* Device-specific region: enet configuration */
 struct vnic_enet_config {
         u32 flags;
@@ -30,6 +34,7 @@ struct vnic_enet_config {
         u8 intr_timer_type;
         u8 intr_mode;
         char devname[16];
+        u32 intr_timer_usec;
 };
 
 #define VENETF_TSO              0x1     /* TSO enabled */
diff --git a/drivers/net/enic/vnic_intr.c b/drivers/net/enic/vnic_intr.c
index 1f8786d7195e..3934309a9498 100644
--- a/drivers/net/enic/vnic_intr.c
+++ b/drivers/net/enic/vnic_intr.c
@@ -50,12 +50,18 @@ int vnic_intr_alloc(struct vnic_dev *vdev, struct vnic_intr *intr,
 void vnic_intr_init(struct vnic_intr *intr, unsigned int coalescing_timer,
         unsigned int coalescing_type, unsigned int mask_on_assertion)
 {
-        iowrite32(coalescing_timer, &intr->ctrl->coalescing_timer);
+        vnic_intr_coalescing_timer_set(intr, coalescing_timer);
         iowrite32(coalescing_type, &intr->ctrl->coalescing_type);
         iowrite32(mask_on_assertion, &intr->ctrl->mask_on_assertion);
         iowrite32(0, &intr->ctrl->int_credits);
 }
 
+void vnic_intr_coalescing_timer_set(struct vnic_intr *intr,
+        unsigned int coalescing_timer)
+{
+        iowrite32(coalescing_timer, &intr->ctrl->coalescing_timer);
+}
+
 void vnic_intr_clean(struct vnic_intr *intr)
 {
         iowrite32(0, &intr->ctrl->int_credits);
diff --git a/drivers/net/enic/vnic_intr.h b/drivers/net/enic/vnic_intr.h
index f79a722b6a03..2fe6c6339e3c 100644
--- a/drivers/net/enic/vnic_intr.h
+++ b/drivers/net/enic/vnic_intr.h
@@ -102,6 +102,8 @@ int vnic_intr_alloc(struct vnic_dev *vdev, struct vnic_intr *intr,
         unsigned int index);
 void vnic_intr_init(struct vnic_intr *intr, unsigned int coalescing_timer,
         unsigned int coalescing_type, unsigned int mask_on_assertion);
+void vnic_intr_coalescing_timer_set(struct vnic_intr *intr,
+        unsigned int coalescing_timer);
 void vnic_intr_clean(struct vnic_intr *intr);
 
 #endif /* _VNIC_INTR_H_ */