sky2: EC-U performance and jumbo support

The Yukon EC Ultra chips have transmit settings for store and
forward and PCI buffering. By setting these appropriately, normal
performance goes from 750Mbytes/sec to 940Mbytes/sec (non-jumbo).

It is also possible to do Jumbo mode, but it means turning off
TSO and checksum offload so the performance gets worse. There isn't
enough buffering for checksum offload to work.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

2 files changed, 68 insertions, 25 deletions

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 910c600a6caf..4d1ec78c437a 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -743,12 +743,17 @@ static void sky2_mac_init(struct sky2_hw *hw, unsigned port)
         if (hw->chip_id == CHIP_ID_YUKON_EC_U || hw->chip_id == CHIP_ID_YUKON_EX) {
                 sky2_write8(hw, SK_REG(port, RX_GMF_LP_THR), 768/8);
                 sky2_write8(hw, SK_REG(port, RX_GMF_UP_THR), 1024/8);
-                if (hw->dev[port]->mtu > ETH_DATA_LEN) {
-                        /* set Tx GMAC FIFO Almost Empty Threshold */
-                        sky2_write32(hw, SK_REG(port, TX_GMF_AE_THR), 0x180);
-                        /* Disable Store & Forward mode for TX */
-                        sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T), TX_STFW_DIS);
-                }
+
+                /* set Tx GMAC FIFO Almost Empty Threshold */
+                sky2_write32(hw, SK_REG(port, TX_GMF_AE_THR),
+                             (ECU_JUMBO_WM << 16) | ECU_AE_THR);
+
+                if (hw->dev[port]->mtu > ETH_DATA_LEN)
+                        sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T),
+                                     TX_JUMBO_ENA | TX_STFW_DIS);
+                else
+                        sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T),
+                                     TX_JUMBO_DIS | TX_STFW_ENA);
         }
 
 }
@@ -1281,7 +1286,7 @@ static int sky2_up(struct net_device *dev)
         /* Set almost empty threshold */
         if (hw->chip_id == CHIP_ID_YUKON_EC_U
             && hw->chip_rev == CHIP_REV_YU_EC_U_A0)
-                sky2_write16(hw, Q_ADDR(txqaddr[port], Q_AL), 0x1a0);
+                sky2_write16(hw, Q_ADDR(txqaddr[port], Q_AL), ECU_TXFF_LEV);
 
         sky2_prefetch_init(hw, txqaddr[port], sky2->tx_le_map,
                            TX_RING_SIZE - 1);
@@ -1587,13 +1592,6 @@ static int sky2_down(struct net_device *dev)
         sky2_write32(hw, RB_ADDR(txqaddr[port], RB_CTRL),
                      RB_RST_SET | RB_DIS_OP_MD);
 
-        /* WA for dev. #4.209 */
-        if (hw->chip_id == CHIP_ID_YUKON_EC_U
-            && (hw->chip_rev == CHIP_REV_YU_EC_U_A1 || hw->chip_rev == CHIP_REV_YU_EC_U_B0))
-                sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T),
-                             sky2->speed != SPEED_1000 ?
-                             TX_STFW_ENA : TX_STFW_DIS);
-
         ctrl = gma_read16(hw, port, GM_GP_CTRL);
         ctrl &= ~(GM_GPCR_TX_ENA | GM_GPCR_RX_ENA);
         gma_write16(hw, port, GM_GP_CTRL, ctrl);
@@ -1893,6 +1891,7 @@ static int sky2_change_mtu(struct net_device *dev, int new_mtu)
 {
         struct sky2_port *sky2 = netdev_priv(dev);
         struct sky2_hw *hw = sky2->hw;
+        unsigned port = sky2->port;
         int err;
         u16 ctl, mode;
         u32 imask;
@@ -1900,10 +1899,6 @@ static int sky2_change_mtu(struct net_device *dev, int new_mtu)
         if (new_mtu < ETH_ZLEN || new_mtu > ETH_JUMBO_MTU)
                 return -EINVAL;
 
-        /* TSO on Yukon Ultra and MTU > 1500 not supported */
-        if (hw->chip_id == CHIP_ID_YUKON_EC_U && new_mtu > ETH_DATA_LEN)
-                dev->features &= ~NETIF_F_TSO;
-
         if (!netif_running(dev)) {
                 dev->mtu = new_mtu;
                 return 0;
@@ -1918,8 +1913,18 @@ static int sky2_change_mtu(struct net_device *dev, int new_mtu)
 
         synchronize_irq(hw->pdev->irq);
 
-        ctl = gma_read16(hw, sky2->port, GM_GP_CTRL);
-        gma_write16(hw, sky2->port, GM_GP_CTRL, ctl & ~GM_GPCR_RX_ENA);
+        if (hw->chip_id == CHIP_ID_YUKON_EC_U || hw->chip_id == CHIP_ID_YUKON_EX) {
+                if (new_mtu > ETH_DATA_LEN) {
+                        sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T),
+                                     TX_JUMBO_ENA | TX_STFW_DIS);
+                        dev->features &= NETIF_F_TSO | NETIF_F_SG | NETIF_F_IP_CSUM;
+                } else
+                        sky2_write32(hw, SK_REG(port, TX_GMF_CTRL_T),
+                                     TX_JUMBO_DIS | TX_STFW_ENA);
+        }
+
+        ctl = gma_read16(hw, port, GM_GP_CTRL);
+        gma_write16(hw, port, GM_GP_CTRL, ctl & ~GM_GPCR_RX_ENA);
         sky2_rx_stop(sky2);
         sky2_rx_clean(sky2);
 
@@ -1931,9 +1936,9 @@ static int sky2_change_mtu(struct net_device *dev, int new_mtu)
         if (dev->mtu > ETH_DATA_LEN)
                 mode |= GM_SMOD_JUMBO_ENA;
 
-        gma_write16(hw, sky2->port, GM_SERIAL_MODE, mode);
+        gma_write16(hw, port, GM_SERIAL_MODE, mode);
 
-        sky2_write8(hw, RB_ADDR(rxqaddr[sky2->port], RB_CTRL), RB_ENA_OP_MD);
+        sky2_write8(hw, RB_ADDR(rxqaddr[port], RB_CTRL), RB_ENA_OP_MD);
 
         err = sky2_rx_start(sky2);
         sky2_write32(hw, B0_IMSK, imask);
@@ -1941,7 +1946,7 @@ static int sky2_change_mtu(struct net_device *dev, int new_mtu)
         if (err)
                 dev_close(dev);
         else {
-                gma_write16(hw, sky2->port, GM_GP_CTRL, ctl);
+                gma_write16(hw, port, GM_GP_CTRL, ctl);
 
                 netif_poll_enable(hw->dev[0]);
                 netif_wake_queue(dev);
@@ -3334,6 +3339,36 @@ static void sky2_get_regs(struct net_device *dev, struct ethtool_regs *regs,
                       regs->len - B3_RI_WTO_R1);
 }
 
+/* In order to do Jumbo packets on these chips, need to turn off the
+ * transmit store/forward. Therefore checksum offload won't work.
+ */
+static int no_tx_offload(struct net_device *dev)
+{
+        const struct sky2_port *sky2 = netdev_priv(dev);
+        const struct sky2_hw *hw = sky2->hw;
+
+        return dev->mtu > ETH_DATA_LEN &&
+                (hw->chip_id == CHIP_ID_YUKON_EX
+                 || hw->chip_id == CHIP_ID_YUKON_EC_U);
+}
+
+static int sky2_set_tx_csum(struct net_device *dev, u32 data)
+{
+        if (data && no_tx_offload(dev))
+                return -EINVAL;
+
+        return ethtool_op_set_tx_csum(dev, data);
+}
+
+
+static int sky2_set_tso(struct net_device *dev, u32 data)
+{
+        if (data && no_tx_offload(dev))
+                return -EINVAL;
+
+        return ethtool_op_set_tso(dev, data);
+}
+
 static const struct ethtool_ops sky2_ethtool_ops = {
         .get_settings = sky2_get_settings,
         .set_settings = sky2_set_settings,
@@ -3349,9 +3384,9 @@ static const struct ethtool_ops sky2_ethtool_ops = {
         .get_sg = ethtool_op_get_sg,
         .set_sg = ethtool_op_set_sg,
         .get_tx_csum = ethtool_op_get_tx_csum,
-        .set_tx_csum = ethtool_op_set_tx_csum,
+        .set_tx_csum = sky2_set_tx_csum,
         .get_tso = ethtool_op_get_tso,
-        .set_tso = ethtool_op_set_tso,
+        .set_tso = sky2_set_tso,
         .get_rx_csum = sky2_get_rx_csum,
         .set_rx_csum = sky2_set_rx_csum,
         .get_strings = sky2_get_strings,
diff --git a/drivers/net/sky2.h b/drivers/net/sky2.h
index 9ca4a2c061c6..5efb5afc45ba 100644
--- a/drivers/net/sky2.h
+++ b/drivers/net/sky2.h
@@ -741,6 +741,11 @@ enum {
         TX_GMF_RP       = 0x0d70,/* 32 bit      Tx GMAC FIFO Read Pointer */
         TX_GMF_RSTP     = 0x0d74,/* 32 bit      Tx GMAC FIFO Restart Pointer */
         TX_GMF_RLEV     = 0x0d78,/* 32 bit      Tx GMAC FIFO Read Level */
+
+        /* Threshold values for Yukon-EC Ultra and Extreme */
+        ECU_AE_THR      = 0x0070, /* Almost Empty Threshold */
+        ECU_TXFF_LEV    = 0x01a0, /* Tx BMU FIFO Level */
+        ECU_JUMBO_WM    = 0x0080, /* Jumbo Mode Watermark */
 };
 
 /* Descriptor Poll Timer Registers */
@@ -1634,6 +1639,9 @@ enum {
         TX_VLAN_TAG_ON  = 1<<25,/* enable  VLAN tagging */
         TX_VLAN_TAG_OFF = 1<<24,/* disable VLAN tagging */
 
+        TX_JUMBO_ENA    = 1<<23,/* PCI Jumbo Mode enable (Yukon-EC Ultra) */
+        TX_JUMBO_DIS    = 1<<22,/* PCI Jumbo Mode enable (Yukon-EC Ultra) */
+
         GMF_WSP_TST_ON  = 1<<18,/* Write Shadow Pointer Test On */
         GMF_WSP_TST_OFF = 1<<17,/* Write Shadow Pointer Test Off */
         GMF_WSP_STEP    = 1<<16,/* Write Shadow Pointer Step/Increment */