From 94c9e5a89349a1f1ebabe0876c059dc387b8b2a0 Mon Sep 17 00:00:00 2001 From: Jesse Brandeburg Date: Mon, 6 Jul 2009 10:44:20 +0000 Subject: 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 Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- drivers/net/e1000/e1000.h | 3 +++ drivers/net/e1000/e1000_ethtool.c | 51 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 53 insertions(+), 1 deletion(-) (limited to 'drivers/net') diff --git a/drivers/net/e1000/e1000.h b/drivers/net/e1000/e1000.h index e9a416f40162..c87f2cbdbae3 100644 --- a/drivers/net/e1000/e1000.h +++ b/drivers/net/e1000/e1000.h @@ -111,6 +111,9 @@ do { \ #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 c854c96f5ab3..27f996a2010f 100644 --- a/drivers/net/e1000/e1000_ethtool.c +++ b/drivers/net/e1000/e1000_ethtool.c @@ -1904,6 +1904,53 @@ static int e1000_phys_id(struct net_device *netdev, u32 data) 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 @@ static const struct ethtool_ops e1000_ethtool_ops = { .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) -- cgit v1.2.2