IB/mthca: 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, 46 insertions, 31 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_main.c b/drivers/infiniband/hw/mthca/mthca_main.c
index 76fed7545c53..04c1520524cd 100644
--- a/drivers/infiniband/hw/mthca/mthca_main.c
+++ b/drivers/infiniband/hw/mthca/mthca_main.c
@@ -61,7 +61,7 @@ MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0");
 
 #ifdef CONFIG_PCI_MSI
 
-static int msi_x = 0;
+static int msi_x = 1;
 module_param(msi_x, int, 0444);
 MODULE_PARM_DESC(msi_x, "attempt to use MSI-X if nonzero");
 
@@ -833,14 +833,19 @@ static int mthca_setup_hca(struct mthca_dev *dev)
 
         err = mthca_NOP(dev, &status);
         if (err || status) {
-                mthca_err(dev, "NOP command failed to generate interrupt (IRQ %d), aborting.\n",
-                          dev->mthca_flags & MTHCA_FLAG_MSI_X ?
-                          dev->eq_table.eq[MTHCA_EQ_CMD].msi_x_vector :
-                          dev->pdev->irq);
-                if (dev->mthca_flags & (MTHCA_FLAG_MSI | MTHCA_FLAG_MSI_X))
-                        mthca_err(dev, "Try again with MSI/MSI-X disabled.\n");
-                else
+                if (dev->mthca_flags & (MTHCA_FLAG_MSI | MTHCA_FLAG_MSI_X)) {
+                        mthca_warn(dev, "NOP command failed to generate interrupt "
+                                   "(IRQ %d).\n",
+                                   dev->mthca_flags & MTHCA_FLAG_MSI_X ?
+                                   dev->eq_table.eq[MTHCA_EQ_CMD].msi_x_vector :
+                                   dev->pdev->irq);
+                        mthca_warn(dev, "Trying again with MSI/MSI-X disabled.\n");
+                } else {
+                        mthca_err(dev, "NOP command failed to generate interrupt "
+                                  "(IRQ %d), aborting.\n",
+                                  dev->pdev->irq);
                         mthca_err(dev, "BIOS or ACPI interrupt routing problem?\n");
+                }
 
                 goto err_cmd_poll;
         }
@@ -1115,24 +1120,6 @@ static int __mthca_init_one(struct pci_dev *pdev, int hca_type)
                 goto err_free_dev;
         }
 
-        if (msi_x && !mthca_enable_msi_x(mdev))
-                mdev->mthca_flags |= MTHCA_FLAG_MSI_X;
-        else if (msi) {
-                static int warned;
-
-                if (!warned) {
-                        printk(KERN_WARNING PFX "WARNING: MSI support will be "
-                               "removed from the ib_mthca driver in January 2008.\n");
-                        printk(KERN_WARNING "    If you are using MSI and cannot "
-                               "switch to MSI-X, please tell "
-                               "<general@lists.openfabrics.org>.\n");
-                        ++warned;
-                }
-
-                if (!pci_enable_msi(pdev))
-                        mdev->mthca_flags |= MTHCA_FLAG_MSI;
-        }
-
         if (mthca_cmd_init(mdev)) {
                 mthca_err(mdev, "Failed to init command interface, aborting.\n");
                 goto err_free_dev;
@@ -1156,7 +1143,35 @@ static int __mthca_init_one(struct pci_dev *pdev, int hca_type)
                 mthca_warn(mdev, "If you have problems, try updating your HCA FW.\n");
         }
 
+        if (msi_x && !mthca_enable_msi_x(mdev))
+                mdev->mthca_flags |= MTHCA_FLAG_MSI_X;
+        else if (msi) {
+                static int warned;
+
+                if (!warned) {
+                        printk(KERN_WARNING PFX "WARNING: MSI support will be "
+                               "removed from the ib_mthca driver in January 2008.\n");
+                        printk(KERN_WARNING "    If you are using MSI and cannot "
+                               "switch to MSI-X, please tell "
+                               "<general@lists.openfabrics.org>.\n");
+                        ++warned;
+                }
+
+                if (!pci_enable_msi(pdev))
+                        mdev->mthca_flags |= MTHCA_FLAG_MSI;
+        }
+
         err = mthca_setup_hca(mdev);
+        if (err == -EBUSY && (mdev->mthca_flags & (MTHCA_FLAG_MSI | MTHCA_FLAG_MSI_X))) {
+                if (mdev->mthca_flags & MTHCA_FLAG_MSI_X)
+                        pci_disable_msix(pdev);
+                if (mdev->mthca_flags & MTHCA_FLAG_MSI)
+                        pci_disable_msi(pdev);
+                mdev->mthca_flags &= ~(MTHCA_FLAG_MSI_X | MTHCA_FLAG_MSI);
+
+                err = mthca_setup_hca(mdev);
+        }
+
         if (err)
                 goto err_close;
 
@@ -1192,17 +1207,17 @@ err_cleanup:
         mthca_cleanup_uar_table(mdev);
 
 err_close:
+        if (mdev->mthca_flags & MTHCA_FLAG_MSI_X)
+                pci_disable_msix(pdev);
+        if (mdev->mthca_flags & MTHCA_FLAG_MSI)
+                pci_disable_msi(pdev);
+
         mthca_close_hca(mdev);
 
 err_cmd:
         mthca_cmd_cleanup(mdev);
 
 err_free_dev:
-        if (mdev->mthca_flags & MTHCA_FLAG_MSI_X)
-                pci_disable_msix(pdev);
-        if (mdev->mthca_flags & MTHCA_FLAG_MSI)
-                pci_disable_msi(pdev);
-
         ib_dealloc_device(&mdev->ib_dev);
 
 err_free_res: