From de5b3077da8275e87196a1e34c5535f5279c5e1a Mon Sep 17 00:00:00 2001 From: Auke Kok Date: Wed, 23 Apr 2008 11:09:08 -0700 Subject: e1000e: Add interrupt moderation run-time ethtool interface The ethtool -c / -C interface can now be used to modify the irq moderation algorithm. This change does not require an adapter reset and can thus be used at all times. The adapter only supports changing/reading rx-usecs which has special values for 0, 1 and 3: 0 - no irq moderation whatsoever 1 - normal moderation favoring regular mixed traffic (default) 3 - best attempt at low latency possible at cost of CPU For values between 10 and 10000 the rx-usecs defines "the minimum time between successive irqs" in usec, unlike the module parameter. Signed-off-by: Auke Kok Signed-off-by: Jeff Garzik --- drivers/net/e1000e/ethtool.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'drivers/net/e1000e/ethtool.c') diff --git a/drivers/net/e1000e/ethtool.c b/drivers/net/e1000e/ethtool.c index c894a6f03bb..ce045acce63 100644 --- a/drivers/net/e1000e/ethtool.c +++ b/drivers/net/e1000e/ethtool.c @@ -1770,6 +1770,47 @@ 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->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 ((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); @@ -1845,6 +1886,8 @@ static const struct ethtool_ops e1000_ethtool_ops = { .phys_id = e1000_phys_id, .get_ethtool_stats = e1000_get_ethtool_stats, .get_sset_count = e1000e_get_sset_count, + .get_coalesce = e1000_get_coalesce, + .set_coalesce = e1000_set_coalesce, }; void e1000e_set_ethtool_ops(struct net_device *netdev) -- cgit v1.2.3