igb_uio: MSI IRQ mode

Add MSI to the list of possible IRQ modes.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
[Thomas: isolate MSI code from other patch and don't set info.irq twice]
Acked-by: Thomas Monjalon <thomas.monjalon@6wind.com>

diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
index 54b1bf9..05cbe8e 100644 (file)
--- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
+++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c
@@ -298,6 +298,24 @@ igbuio_msix_mask_irq(struct msi_desc *desc, int32_t state)
        }
 }
 
+static void
+igbuio_msi_mask_irq(struct irq_data *data, u32 enable)
+{
+       struct msi_desc *desc = irq_data_get_msi(data);
+       u32 mask_bits = desc->masked;
+       unsigned offset = data->irq - desc->dev->irq;
+       u32 mask = 1 << offset;
+       u32 flag = enable << offset;
+
+       mask_bits &= ~mask;
+       mask_bits |= flag;
+
+       if (desc->msi_attrib.maskbit && mask_bits != desc->masked) {
+               pci_write_config_dword(desc->dev, desc->mask_pos, mask_bits);
+               desc->masked = mask_bits;
+       }
+}
+
 /**
  * This is the irqcontrol callback to be registered to uio_info.
  * It can be used to disable/enable interrupt from user space processes.
@@ -320,8 +338,11 @@ igbuio_pci_irqcontrol(struct uio_info *info, s32 irq_state)
        pci_cfg_access_lock(pdev);
        if (udev->mode == RTE_INTR_MODE_LEGACY)
                pci_intx(pdev, !!irq_state);
+       else if (udev->mode == RTE_INTR_MODE_MSI) {
+               struct irq_data *data = irq_get_irq_data(pdev->irq);
 
-       else if (udev->mode == RTE_INTR_MODE_MSIX) {
+               igbuio_msi_mask_irq(data, !!irq_state);
+       } else if (udev->mode == RTE_INTR_MODE_MSIX) {
                struct msi_desc *desc;
 
                list_for_each_entry(desc, &pdev->msi_list, list)
@@ -578,6 +599,13 @@ igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
                        udev->mode = RTE_INTR_MODE_MSIX;
                        break;
                }
+               /* fall back to MSI */
+       case RTE_INTR_MODE_MSI:
+               if (pci_enable_msi(dev) == 0) {
+                       dev_dbg(&dev->dev, "using MSI");
+                       udev->mode = RTE_INTR_MODE_MSI;
+                       break;
+               }
                /* fall back to INTX */
        case RTE_INTR_MODE_LEGACY:
                if (pci_intx_mask_supported(dev)) {
@@ -619,6 +647,8 @@ fail_release_iomem:
        igbuio_pci_release_iomem(&udev->info);
        if (udev->mode == RTE_INTR_MODE_MSIX)
                pci_disable_msix(udev->pdev);
+       else if (udev->mode == RTE_INTR_MODE_MSI)
+               pci_disable_msi(udev->pdev);
        pci_release_regions(dev);
 fail_disable:
        pci_disable_device(dev);
@@ -644,6 +674,8 @@ igbuio_pci_remove(struct pci_dev *dev)
        igbuio_pci_release_iomem(info);
        if (udev->mode == RTE_INTR_MODE_MSIX)
                pci_disable_msix(dev);
+       else if (udev->mode == RTE_INTR_MODE_MSI)
+               pci_disable_msi(dev);
        pci_release_regions(dev);
        pci_disable_device(dev);
        pci_set_drvdata(dev, NULL);
@@ -661,6 +693,9 @@ igbuio_config_intr_mode(char *intr_str)
        if (!strcmp(intr_str, RTE_INTR_MODE_MSIX_NAME)) {
                igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX;
                pr_info("Use MSIX interrupt\n");
+       } else if (!strcmp(intr_str, RTE_INTR_MODE_MSI_NAME)) {
+               igbuio_intr_mode_preferred = RTE_INTR_MODE_MSI;
+               pr_info("Use MSI interrupt\n");
        } else if (!strcmp(intr_str, RTE_INTR_MODE_LEGACY_NAME)) {
                igbuio_intr_mode_preferred = RTE_INTR_MODE_LEGACY;
                pr_info("Use legacy interrupt\n");
@@ -704,6 +739,7 @@ module_param(intr_mode, charp, S_IRUGO);
 MODULE_PARM_DESC(intr_mode,
 "igb_uio interrupt mode (default=msix):\n"
 "    " RTE_INTR_MODE_MSIX_NAME "       Use MSIX interrupt\n"
+"    " RTE_INTR_MODE_MSI_NAME "        Use MSI interrupt\n"
 "    " RTE_INTR_MODE_LEGACY_NAME "     Use Legacy interrupt\n"
 "\n");