bnx2: Fix lost MSI-X problem on 5709 NICs.

It has been reported that under certain heavy traffic conditions in MSI-X
mode, the driver can lose an MSI-X vector causing all packets in the
associated rx/tx ring pair to be dropped.  The problem is caused by
the chip dropping the write to unmask the MSI-X vector by the kernel
(when migrating the IRQ for example).

This can be prevented by increasing the GRC timeout value for these
register read and write operations.

Thanks to Dell for helping us debug this problem.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index a257babd1bb4085c184604c4d0b8dcdbbc59f203..4c1e51ee8ede28634fef0fa2d140e090fbf86315 100644 (file)
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -4759,8 +4759,12 @@ bnx2_reset_chip(struct bnx2 *bp, u32 reset_code)
                rc = bnx2_alloc_bad_rbuf(bp);
        }
 
-       if (bp->flags & BNX2_FLAG_USING_MSIX)
+       if (bp->flags & BNX2_FLAG_USING_MSIX) {
                bnx2_setup_msix_tbl(bp);
+               /* Prevent MSIX table reads and write from timing out */
+               REG_WR(bp, BNX2_MISC_ECO_HW_CTL,
+                       BNX2_MISC_ECO_HW_CTL_LARGE_GRC_TMOUT_EN);
+       }
 
        return rc;
 }