e1000e: 82579 performance improvements

The initial support for 82579 was tuned poorly for performance.  Adjust the
packet buffer allocation appropriately for both standard and jumbo frames;
and for jumbo frames increase the receive descriptor pre-fetch, disable
adaptive interrupt moderation and set the DMA latency tolerance.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 46 insertions, 7 deletions

diff --git a/drivers/net/e1000e/e1000.h b/drivers/net/e1000e/e1000.h
index 5ec0af59eeab..cee882dd67bf 100644
--- a/drivers/net/e1000e/e1000.h
+++ b/drivers/net/e1000e/e1000.h
@@ -453,6 +453,7 @@ struct e1000_info {
 #define FLAG2_HAS_PHY_STATS               (1 << 4)
 #define FLAG2_HAS_EEE                     (1 << 5)
 #define FLAG2_DMA_BURST                   (1 << 6)
+#define FLAG2_DISABLE_AIM                 (1 << 8)
 
 #define E1000_RX_DESC_PS(R, i)      \
         (&(((union e1000_rx_desc_packet_split *)((R).desc))[i]))
diff --git a/drivers/net/e1000e/ich8lan.c b/drivers/net/e1000e/ich8lan.c
index 57b5435599ab..e3374d9a2472 100644
--- a/drivers/net/e1000e/ich8lan.c
+++ b/drivers/net/e1000e/ich8lan.c
@@ -3986,7 +3986,7 @@ struct e1000_info e1000_pch2_info = {
                                   | FLAG_APME_IN_WUC,
         .flags2                 = FLAG2_HAS_PHY_STATS
                                   | FLAG2_HAS_EEE,
-        .pba                    = 18,
+        .pba                    = 26,
         .max_hw_frame_size      = DEFAULT_JUMBO,
         .get_variants           = e1000_get_variants_ich8lan,
         .mac_ops                = &ich8_mac_ops,
diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 1aa4228e860a..992b622fe205 100644
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -2290,6 +2290,11 @@ static void e1000_set_itr(struct e1000_adapter *adapter)
                 goto set_itr_now;
         }
 
+        if (adapter->flags2 & FLAG2_DISABLE_AIM) {
+                new_itr = 0;
+                goto set_itr_now;
+        }
+
         adapter->tx_itr = e1000_update_itr(adapter,
                                     adapter->tx_itr,
                                     adapter->total_tx_packets,
@@ -2338,7 +2343,10 @@ set_itr_now:
                 if (adapter->msix_entries)
                         adapter->rx_ring->set_itr = 1;
                 else
-                        ew32(ITR, 1000000000 / (new_itr * 256));
+                        if (new_itr)
+                                ew32(ITR, 1000000000 / (new_itr * 256));
+                        else
+                                ew32(ITR, 0);
         }
 }
 
@@ -2920,7 +2928,7 @@ static void e1000_configure_rx(struct e1000_adapter *adapter)
 
         /* irq moderation */
         ew32(RADV, adapter->rx_abs_int_delay);
-        if (adapter->itr_setting != 0)
+        if ((adapter->itr_setting != 0) && (adapter->itr != 0))
                 ew32(ITR, 1000000000 / (adapter->itr * 256));
 
         ctrl_ext = er32(CTRL_EXT);
@@ -2965,11 +2973,13 @@ static void e1000_configure_rx(struct e1000_adapter *adapter)
          * packet size is equal or larger than the specified value (in 8 byte
          * units), e.g. using jumbo frames when setting to E1000_ERT_2048
          */
-        if (adapter->flags & FLAG_HAS_ERT) {
+        if ((adapter->flags & FLAG_HAS_ERT) ||
+            (adapter->hw.mac.type == e1000_pch2lan)) {
                 if (adapter->netdev->mtu > ETH_DATA_LEN) {
                         u32 rxdctl = er32(RXDCTL(0));
                         ew32(RXDCTL(0), rxdctl | 0x3);
-                        ew32(ERT, E1000_ERT_2048 | (1 << 13));
+                        if (adapter->flags & FLAG_HAS_ERT)
+                                ew32(ERT, E1000_ERT_2048 | (1 << 13));
                         /*
                          * With jumbo frames and early-receive enabled,
                          * excessive C-state transition latencies result in
@@ -3232,9 +3242,35 @@ void e1000e_reset(struct e1000_adapter *adapter)
                 fc->low_water = 0x05048;
                 fc->pause_time = 0x0650;
                 fc->refresh_time = 0x0400;
+                if (adapter->netdev->mtu > ETH_DATA_LEN) {
+                        pba = 14;
+                        ew32(PBA, pba);
+                }
                 break;
         }
 
+        /*
+         * Disable Adaptive Interrupt Moderation if 2 full packets cannot
+         * fit in receive buffer and early-receive not supported.
+         */
+        if (adapter->itr_setting & 0x3) {
+                if (((adapter->max_frame_size * 2) > (pba << 10)) &&
+                    !(adapter->flags & FLAG_HAS_ERT)) {
+                        if (!(adapter->flags2 & FLAG2_DISABLE_AIM)) {
+                                dev_info(&adapter->pdev->dev,
+                                        "Interrupt Throttle Rate turned off\n");
+                                adapter->flags2 |= FLAG2_DISABLE_AIM;
+                                ew32(ITR, 0);
+                        }
+                } else if (adapter->flags2 & FLAG2_DISABLE_AIM) {
+                        dev_info(&adapter->pdev->dev,
+                                 "Interrupt Throttle Rate turned on\n");
+                        adapter->flags2 &= ~FLAG2_DISABLE_AIM;
+                        adapter->itr = 20000;
+                        ew32(ITR, 1000000000 / (adapter->itr * 256));
+                }
+        }
+
         /* Allow time for pending master requests to run */
         mac->ops.reset_hw(hw);
 
@@ -3553,7 +3589,8 @@ static int e1000_open(struct net_device *netdev)
                 e1000_update_mng_vlan(adapter);
 
         /* DMA latency requirement to workaround early-receive/jumbo issue */
-        if (adapter->flags & FLAG_HAS_ERT)
+        if ((adapter->flags & FLAG_HAS_ERT) ||
+            (adapter->hw.mac.type == e1000_pch2lan))
                 pm_qos_add_request(&adapter->netdev->pm_qos_req,
                                    PM_QOS_CPU_DMA_LATENCY,
                                    PM_QOS_DEFAULT_VALUE);
@@ -3662,7 +3699,8 @@ static int e1000_close(struct net_device *netdev)
         if (adapter->flags & FLAG_HAS_AMT)
                 e1000_release_hw_control(adapter);
 
-        if (adapter->flags & FLAG_HAS_ERT)
+        if ((adapter->flags & FLAG_HAS_ERT) ||
+            (adapter->hw.mac.type == e1000_pch2lan))
                 pm_qos_remove_request(&adapter->netdev->pm_qos_req);
 
         pm_runtime_put_sync(&pdev->dev);