e1000: allow ethtool coalesece to adjust interrupts per second
This patch allows on-the-fly adjustment of the interrupts per second generated
by e1000 devices 82545/82546 (hardware support of ITR register is a
requirement)
adjust using this command:
ethtool -C eth0 rx-usecs 10
where 10 is 10 microseconds per interrupt interval, so 10 = 100,000 interrupts
per second, and 125 = 8000 interrupts per second.
changes should be immediate.
1,3 are special values and indicate the automatic tuning mode to the driver,
where 1 is 4000-90000 interrupts per second and 3 is 4000-20000 interrupts
per second and is the driver default.
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/e1000/e1000.h b/drivers/net/e1000/e1000.h
index e9a416f..c87f2cb 100644
--- a/drivers/net/e1000/e1000.h
+++ b/drivers/net/e1000/e1000.h
@@ -111,6 +111,9 @@
#define E1000_MIN_RXD 80
#define E1000_MAX_82544_RXD 4096
+#define E1000_MIN_ITR_USECS 10 /* 100000 irq/sec */
+#define E1000_MAX_ITR_USECS 10000 /* 100 irq/sec */
+
/* this is the size past which hardware will drop packets when setting LPE=0 */
#define MAXIMUM_ETHERNET_VLAN_SIZE 1522
diff --git a/drivers/net/e1000/e1000_ethtool.c b/drivers/net/e1000/e1000_ethtool.c
index c854c96..27f996a 100644
--- a/drivers/net/e1000/e1000_ethtool.c
+++ b/drivers/net/e1000/e1000_ethtool.c
@@ -1904,6 +1904,53 @@
return 0;
}
+static int e1000_get_coalesce(struct net_device *netdev,
+ struct ethtool_coalesce *ec)
+{
+ struct e1000_adapter *adapter = netdev_priv(netdev);
+
+ if (adapter->hw.mac_type < e1000_82545)
+ return -EOPNOTSUPP;
+
+ if (adapter->itr_setting <= 3)
+ ec->rx_coalesce_usecs = adapter->itr_setting;
+ else
+ ec->rx_coalesce_usecs = 1000000 / adapter->itr_setting;
+
+ return 0;
+}
+
+static int e1000_set_coalesce(struct net_device *netdev,
+ struct ethtool_coalesce *ec)
+{
+ struct e1000_adapter *adapter = netdev_priv(netdev);
+ struct e1000_hw *hw = &adapter->hw;
+
+ if (hw->mac_type < e1000_82545)
+ return -EOPNOTSUPP;
+
+ if ((ec->rx_coalesce_usecs > E1000_MAX_ITR_USECS) ||
+ ((ec->rx_coalesce_usecs > 3) &&
+ (ec->rx_coalesce_usecs < E1000_MIN_ITR_USECS)) ||
+ (ec->rx_coalesce_usecs == 2))
+ return -EINVAL;
+
+ if (ec->rx_coalesce_usecs <= 3) {
+ adapter->itr = 20000;
+ adapter->itr_setting = ec->rx_coalesce_usecs;
+ } else {
+ adapter->itr = (1000000 / ec->rx_coalesce_usecs);
+ adapter->itr_setting = adapter->itr & ~3;
+ }
+
+ if (adapter->itr_setting != 0)
+ ew32(ITR, 1000000000 / (adapter->itr * 256));
+ else
+ ew32(ITR, 0);
+
+ return 0;
+}
+
static int e1000_nway_reset(struct net_device *netdev)
{
struct e1000_adapter *adapter = netdev_priv(netdev);
@@ -1978,7 +2025,9 @@
.get_strings = e1000_get_strings,
.phys_id = e1000_phys_id,
.get_ethtool_stats = e1000_get_ethtool_stats,
- .get_sset_count = e1000_get_sset_count,
+ .get_sset_count = e1000_get_sset_count,
+ .get_coalesce = e1000_get_coalesce,
+ .set_coalesce = e1000_set_coalesce,
};
void e1000_set_ethtool_ops(struct net_device *netdev)