mlx4_core: Enable MSI-X by default

Recover from MSI-X errors by automatically falling back on regular
interrupt, instead of asking the user to do this manually.  This makes
it possible to enable MSI-X by default, and will make it possible to
get rid of the msi_x module option in the future.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 22 insertions, 12 deletions

diff --git a/drivers/net/mlx4/main.c b/drivers/net/mlx4/main.c
index 4dc9dc19b716..4b1269435586 100644
--- a/drivers/net/mlx4/main.c
+++ b/drivers/net/mlx4/main.c
@@ -61,7 +61,7 @@ MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0");
 
 #ifdef CONFIG_PCI_MSI
 
-static int msi_x;
+static int msi_x = 1;
 module_param(msi_x, int, 0444);
 MODULE_PARM_DESC(msi_x, "attempt to use MSI-X if nonzero");
 
@@ -599,13 +599,17 @@ static int __devinit mlx4_setup_hca(struct mlx4_dev *dev)
 
         err = mlx4_NOP(dev);
         if (err) {
-                mlx4_err(dev, "NOP command failed to generate interrupt "
-                         "(IRQ %d), aborting.\n",
-                         priv->eq_table.eq[MLX4_EQ_ASYNC].irq);
-                if (dev->flags & MLX4_FLAG_MSI_X)
-                        mlx4_err(dev, "Try again with MSI-X disabled.\n");
-                else
+                if (dev->flags & MLX4_FLAG_MSI_X) {
+                        mlx4_warn(dev, "NOP command failed to generate MSI-X "
+                                  "interrupt IRQ %d).\n",
+                                  priv->eq_table.eq[MLX4_EQ_ASYNC].irq);
+                        mlx4_warn(dev, "Trying again without MSI-X.\n");
+                } else {
+                        mlx4_err(dev, "NOP command failed to generate interrupt "
+                                 "(IRQ %d), aborting.\n",
+                                 priv->eq_table.eq[MLX4_EQ_ASYNC].irq);
                         mlx4_err(dev, "BIOS or ACPI interrupt routing problem?\n");
+                }
 
                 goto err_cmd_poll;
         }
@@ -803,8 +807,6 @@ static int __devinit mlx4_init_one(struct pci_dev *pdev,
                 goto err_free_dev;
         }
 
-        mlx4_enable_msi_x(dev);
-
         if (mlx4_cmd_init(dev)) {
                 mlx4_err(dev, "Failed to init command interface, aborting.\n");
                 goto err_free_dev;
@@ -814,7 +816,15 @@ static int __devinit mlx4_init_one(struct pci_dev *pdev,
         if (err)
                 goto err_cmd;
 
+        mlx4_enable_msi_x(dev);
+
         err = mlx4_setup_hca(dev);
+        if (err == -EBUSY && (dev->flags & MLX4_FLAG_MSI_X)) {
+                dev->flags &= ~MLX4_FLAG_MSI_X;
+                pci_disable_msix(pdev);
+                err = mlx4_setup_hca(dev);
+        }
+
         if (err)
                 goto err_close;
 
@@ -838,15 +848,15 @@ err_cleanup:
         mlx4_cleanup_uar_table(dev);
 
 err_close:
+        if (dev->flags & MLX4_FLAG_MSI_X)
+                pci_disable_msix(pdev);
+
         mlx4_close_hca(dev);
 
 err_cmd:
         mlx4_cmd_cleanup(dev);
 
 err_free_dev:
-        if (dev->flags & MLX4_FLAG_MSI_X)
-                pci_disable_msix(pdev);
-
         kfree(priv);
 
 err_release_bar2: