1 files changed, 76 insertions, 4 deletions

diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 362f70382cdd..2198e615f241 100644
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -519,6 +519,63 @@ static void e1000_rx_checksum(struct e1000_adapter *adapter, u32 status_err,
 }
 
 /**
+ * e1000e_update_tail_wa - helper function for e1000e_update_[rt]dt_wa()
+ * @hw: pointer to the HW structure
+ * @tail: address of tail descriptor register
+ * @i: value to write to tail descriptor register
+ *
+ * When updating the tail register, the ME could be accessing Host CSR
+ * registers at the same time.  Normally, this is handled in h/w by an
+ * arbiter but on some parts there is a bug that acknowledges Host accesses
+ * later than it should which could result in the descriptor register to
+ * have an incorrect value.  Workaround this by checking the FWSM register
+ * which has bit 24 set while ME is accessing Host CSR registers, wait
+ * if it is set and try again a number of times.
+ **/
+static inline s32 e1000e_update_tail_wa(struct e1000_hw *hw, u8 __iomem * tail,
+                                        unsigned int i)
+{
+        unsigned int j = 0;
+
+        while ((j++ < E1000_ICH_FWSM_PCIM2PCI_COUNT) &&
+               (er32(FWSM) & E1000_ICH_FWSM_PCIM2PCI))
+                udelay(50);
+
+        writel(i, tail);
+
+        if ((j == E1000_ICH_FWSM_PCIM2PCI_COUNT) && (i != readl(tail)))
+                return E1000_ERR_SWFW_SYNC;
+
+        return 0;
+}
+
+static void e1000e_update_rdt_wa(struct e1000_adapter *adapter, unsigned int i)
+{
+        u8 __iomem *tail = (adapter->hw.hw_addr + adapter->rx_ring->tail);
+        struct e1000_hw *hw = &adapter->hw;
+
+        if (e1000e_update_tail_wa(hw, tail, i)) {
+                u32 rctl = er32(RCTL);
+                ew32(RCTL, rctl & ~E1000_RCTL_EN);
+                e_err("ME firmware caused invalid RDT - resetting\n");
+                schedule_work(&adapter->reset_task);
+        }
+}
+
+static void e1000e_update_tdt_wa(struct e1000_adapter *adapter, unsigned int i)
+{
+        u8 __iomem *tail = (adapter->hw.hw_addr + adapter->tx_ring->tail);
+        struct e1000_hw *hw = &adapter->hw;
+
+        if (e1000e_update_tail_wa(hw, tail, i)) {
+                u32 tctl = er32(TCTL);
+                ew32(TCTL, tctl & ~E1000_TCTL_EN);
+                e_err("ME firmware caused invalid TDT - resetting\n");
+                schedule_work(&adapter->reset_task);
+        }
+}
+
+/**
  * e1000_alloc_rx_buffers - Replace used receive buffers; legacy & extended
  * @adapter: address of board private structure
  **/
@@ -573,7 +630,10 @@ map_skb:
                          * such as IA-64).
                          */
                         wmb();
-                        writel(i, adapter->hw.hw_addr + rx_ring->tail);
+                        if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
+                                e1000e_update_rdt_wa(adapter, i);
+                        else
+                                writel(i, adapter->hw.hw_addr + rx_ring->tail);
                 }
                 i++;
                 if (i == rx_ring->count)
@@ -673,7 +733,11 @@ static void e1000_alloc_rx_buffers_ps(struct e1000_adapter *adapter,
                          * such as IA-64).
                          */
                         wmb();
-                        writel(i << 1, adapter->hw.hw_addr + rx_ring->tail);
+                        if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
+                                e1000e_update_rdt_wa(adapter, i << 1);
+                        else
+                                writel(i << 1,
+                                       adapter->hw.hw_addr + rx_ring->tail);
                 }
 
                 i++;
@@ -756,7 +820,10 @@ check_page:
                  * applicable for weak-ordered memory model archs,
                  * such as IA-64). */
                 wmb();
-                writel(i, adapter->hw.hw_addr + rx_ring->tail);
+                if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
+                        e1000e_update_rdt_wa(adapter, i);
+                else
+                        writel(i, adapter->hw.hw_addr + rx_ring->tail);
         }
 }
 
@@ -4689,7 +4756,12 @@ static void e1000_tx_queue(struct e1000_adapter *adapter,
         wmb();
 
         tx_ring->next_to_use = i;
-        writel(i, adapter->hw.hw_addr + tx_ring->tail);
+
+        if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
+                e1000e_update_tdt_wa(adapter, i);
+        else
+                writel(i, adapter->hw.hw_addr + tx_ring->tail);
+
         /*
          * we need this if more than one processor can write to our tail
          * at a time, it synchronizes IO on IA64/Altix systems