From 3e5080344e95c0861a7ca494288593023ee383c6 Mon Sep 17 00:00:00 2001 From: Lennert Buytenhek Date: Thu, 12 Feb 2009 14:07:09 +0000 Subject: [PATCH] mv643xx_eth: rework interrupt coalescing, and export via ethtool This patch: - increases the precision of the receive/transmit interrupt coalescing register value computations by using 64bit temporaries; - adds functions to read the current hardware coalescing register values and convert them back to usecs; - exports the {get,set} {rx,tx} coal methods via the standard ethtool coalescing interface. Signed-off-by: Lennert Buytenhek Signed-off-by: David S. Miller --- drivers/net/mv643xx_eth.c | 133 +++++++++++++++++++++++++++++--------- 1 file changed, 103 insertions(+), 30 deletions(-) diff --git a/drivers/net/mv643xx_eth.c b/drivers/net/mv643xx_eth.c index e8fbc0badf7..c32d623061d 100644 --- a/drivers/net/mv643xx_eth.c +++ b/drivers/net/mv643xx_eth.c @@ -1221,6 +1221,85 @@ static void mib_counters_timer_wrapper(unsigned long _mp) } +/* interrupt coalescing *****************************************************/ +/* + * Hardware coalescing parameters are set in units of 64 t_clk + * cycles. I.e.: + * + * coal_delay_in_usec = 64000000 * register_value / t_clk_rate + * + * register_value = coal_delay_in_usec * t_clk_rate / 64000000 + * + * In the ->set*() methods, we round the computed register value + * to the nearest integer. + */ +static unsigned int get_rx_coal(struct mv643xx_eth_private *mp) +{ + u32 val = rdlp(mp, SDMA_CONFIG); + u64 temp; + + if (mp->shared->extended_rx_coal_limit) + temp = ((val & 0x02000000) >> 10) | ((val & 0x003fff80) >> 7); + else + temp = (val & 0x003fff00) >> 8; + + temp *= 64000000; + do_div(temp, mp->shared->t_clk); + + return (unsigned int)temp; +} + +static void set_rx_coal(struct mv643xx_eth_private *mp, unsigned int usec) +{ + u64 temp; + u32 val; + + temp = (u64)usec * mp->shared->t_clk; + temp += 31999999; + do_div(temp, 64000000); + + val = rdlp(mp, SDMA_CONFIG); + if (mp->shared->extended_rx_coal_limit) { + if (temp > 0xffff) + temp = 0xffff; + val &= ~0x023fff80; + val |= (temp & 0x8000) << 10; + val |= (temp & 0x7fff) << 7; + } else { + if (temp > 0x3fff) + temp = 0x3fff; + val &= ~0x003fff00; + val |= (temp & 0x3fff) << 8; + } + wrlp(mp, SDMA_CONFIG, val); +} + +static unsigned int get_tx_coal(struct mv643xx_eth_private *mp) +{ + u64 temp; + + temp = (rdlp(mp, TX_FIFO_URGENT_THRESHOLD) & 0x3fff0) >> 4; + temp *= 64000000; + do_div(temp, mp->shared->t_clk); + + return (unsigned int)temp; +} + +static void set_tx_coal(struct mv643xx_eth_private *mp, unsigned int usec) +{ + u64 temp; + + temp = (u64)usec * mp->shared->t_clk; + temp += 31999999; + do_div(temp, 64000000); + + if (temp > 0x3fff) + temp = 0x3fff; + + wrlp(mp, TX_FIFO_URGENT_THRESHOLD, temp << 4); +} + + /* ethtool ******************************************************************/ struct mv643xx_eth_stats { char stat_string[ETH_GSTRING_LEN]; @@ -1384,6 +1463,28 @@ static u32 mv643xx_eth_get_link(struct net_device *dev) return !!netif_carrier_ok(dev); } +static int +mv643xx_eth_get_coalesce(struct net_device *dev, struct ethtool_coalesce *ec) +{ + struct mv643xx_eth_private *mp = netdev_priv(dev); + + ec->rx_coalesce_usecs = get_rx_coal(mp); + ec->tx_coalesce_usecs = get_tx_coal(mp); + + return 0; +} + +static int +mv643xx_eth_set_coalesce(struct net_device *dev, struct ethtool_coalesce *ec) +{ + struct mv643xx_eth_private *mp = netdev_priv(dev); + + set_rx_coal(mp, ec->rx_coalesce_usecs); + set_tx_coal(mp, ec->tx_coalesce_usecs); + + return 0; +} + static void mv643xx_eth_get_strings(struct net_device *dev, uint32_t stringset, uint8_t *data) { @@ -1438,6 +1539,8 @@ static const struct ethtool_ops mv643xx_eth_ethtool_ops = { .get_drvinfo = mv643xx_eth_get_drvinfo, .nway_reset = mv643xx_eth_nway_reset, .get_link = mv643xx_eth_get_link, + .get_coalesce = mv643xx_eth_get_coalesce, + .set_coalesce = mv643xx_eth_set_coalesce, .set_sg = ethtool_op_set_sg, .get_strings = mv643xx_eth_get_strings, .get_ethtool_stats = mv643xx_eth_get_ethtool_stats, @@ -2053,36 +2156,6 @@ static void port_start(struct mv643xx_eth_private *mp) } } -static void set_rx_coal(struct mv643xx_eth_private *mp, unsigned int delay) -{ - unsigned int coal = ((mp->shared->t_clk / 1000000) * delay) / 64; - u32 val; - - val = rdlp(mp, SDMA_CONFIG); - if (mp->shared->extended_rx_coal_limit) { - if (coal > 0xffff) - coal = 0xffff; - val &= ~0x023fff80; - val |= (coal & 0x8000) << 10; - val |= (coal & 0x7fff) << 7; - } else { - if (coal > 0x3fff) - coal = 0x3fff; - val &= ~0x003fff00; - val |= (coal & 0x3fff) << 8; - } - wrlp(mp, SDMA_CONFIG, val); -} - -static void set_tx_coal(struct mv643xx_eth_private *mp, unsigned int delay) -{ - unsigned int coal = ((mp->shared->t_clk / 1000000) * delay) / 64; - - if (coal > 0x3fff) - coal = 0x3fff; - wrlp(mp, TX_FIFO_URGENT_THRESHOLD, (coal & 0x3fff) << 4); -} - static void mv643xx_eth_recalc_skb_size(struct mv643xx_eth_private *mp) { int skb_size;