ixgbe: consolidate reporting of MSIX vectors into a single function

This patch modifies ixgbe_get_pcie_msix_count_generic() to support
all current HW and removes the 82598 specific function.

- change the type of ixgbe_get_pcie_msix_count_generic() to u16
- include a check to make sure the maximum allowed number of vectors
is not exceeded.

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 24 insertions, 5 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
index 49aa41fe7b84..e59888163a17 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
@@ -2783,17 +2783,36 @@ san_mac_addr_out:
  *  Read PCIe configuration space, and get the MSI-X vector count from
  *  the capabilities table.
  **/
-u32 ixgbe_get_pcie_msix_count_generic(struct ixgbe_hw *hw)
+u16 ixgbe_get_pcie_msix_count_generic(struct ixgbe_hw *hw)
 {
 	struct ixgbe_adapter *adapter = hw->back;
-	u16 msix_count;
-	pci_read_config_word(adapter->pdev, IXGBE_PCIE_MSIX_82599_CAPS,
-	                     &msix_count);
+	u16 msix_count = 1;
+	u16 max_msix_count;
+	u16 pcie_offset;
+
+	switch (hw->mac.type) {
+	case ixgbe_mac_82598EB:
+		pcie_offset = IXGBE_PCIE_MSIX_82598_CAPS;
+		max_msix_count = IXGBE_MAX_MSIX_VECTORS_82598;
+		break;
+	case ixgbe_mac_82599EB:
+	case ixgbe_mac_X540:
+		pcie_offset = IXGBE_PCIE_MSIX_82599_CAPS;
+		max_msix_count = IXGBE_MAX_MSIX_VECTORS_82599;
+		break;
+	default:
+		return msix_count;
+	}
+
+	pci_read_config_word(adapter->pdev, pcie_offset, &msix_count);
 	msix_count &= IXGBE_PCIE_MSIX_TBL_SZ_MASK;
 
-	/* MSI-X count is zero-based in HW, so increment to give proper value */
+	/* MSI-X count is zero-based in HW */
 	msix_count++;
 
+	if (msix_count > max_msix_count)
+		msix_count = max_msix_count;
+
 	return msix_count;
 }