+#define PCI_MSIX_ENABLE 0x8000
+
+static enum virtio_msix_status
+vtpci_msix_detect(struct rte_pci_device *dev)
+{
+ uint8_t pos;
+ int ret;
+
+ ret = rte_pci_read_config(dev, &pos, 1, PCI_CAPABILITY_LIST);
+ if (ret != 1) {
+ PMD_INIT_LOG(DEBUG,
+ "failed to read pci capability list, ret %d", ret);
+ return VIRTIO_MSIX_NONE;
+ }
+
+ while (pos) {
+ uint8_t cap[2];
+
+ ret = rte_pci_read_config(dev, cap, sizeof(cap), pos);
+ if (ret != sizeof(cap)) {
+ PMD_INIT_LOG(DEBUG,
+ "failed to read pci cap at pos: %x ret %d",
+ pos, ret);
+ break;
+ }
+
+ if (cap[0] == PCI_CAP_ID_MSIX) {
+ uint16_t flags;
+
+ ret = rte_pci_read_config(dev, &flags, sizeof(flags),
+ pos + sizeof(cap));
+ if (ret != sizeof(flags)) {
+ PMD_INIT_LOG(DEBUG,
+ "failed to read pci cap at pos:"
+ " %x ret %d", pos + 2, ret);
+ break;
+ }
+
+ if (flags & PCI_MSIX_ENABLE)
+ return VIRTIO_MSIX_ENABLED;
+ else
+ return VIRTIO_MSIX_DISABLED;
+ }
+
+ pos = cap[1];
+ }
+
+ return VIRTIO_MSIX_NONE;
+}
+