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>

drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c

@@ -91,29 +91,6 @@ out:
 	IXGBE_WRITE_REG(hw, IXGBE_GCR, gcr);
 }
 
-/**
- *  ixgbe_get_pcie_msix_count_82598 - Gets MSI-X vector count
- *  @hw: pointer to hardware structure
- *
- *  Read PCIe configuration space, and get the MSI-X vector count from
- *  the capabilities table.
- **/
-static u16 ixgbe_get_pcie_msix_count_82598(struct ixgbe_hw *hw)
-{
-	struct ixgbe_adapter *adapter = hw->back;
-	u16 msix_count;
-	pci_read_config_word(adapter->pdev, IXGBE_PCIE_MSIX_82598_CAPS,
-	                     &msix_count);
-	msix_count &= IXGBE_PCIE_MSIX_TBL_SZ_MASK;
-
-	/* MSI-X count is zero-based in HW, so increment to give proper value */
-	msix_count++;
-
-	return msix_count;
-}
-
-/**
- */
 static s32 ixgbe_get_invariants_82598(struct ixgbe_hw *hw)
 {
 	struct ixgbe_mac_info *mac = &hw->mac;
@@ -126,7 +103,7 @@ static s32 ixgbe_get_invariants_82598(struct ixgbe_hw *hw)
 	mac->num_rar_entries = IXGBE_82598_RAR_ENTRIES;
 	mac->max_rx_queues = IXGBE_82598_MAX_RX_QUEUES;
 	mac->max_tx_queues = IXGBE_82598_MAX_TX_QUEUES;
-	mac->max_msix_vectors = ixgbe_get_pcie_msix_count_82598(hw);
+	mac->max_msix_vectors = ixgbe_get_pcie_msix_count_generic(hw);
 
 	return 0;
 }

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;
 }
 

drivers/net/ethernet/intel/ixgbe/ixgbe_common.h

@@ -31,7 +31,7 @@
 #include "ixgbe_type.h"
 #include "ixgbe.h"
 
-u32 ixgbe_get_pcie_msix_count_generic(struct ixgbe_hw *hw);
+u16 ixgbe_get_pcie_msix_count_generic(struct ixgbe_hw *hw);
 s32 ixgbe_init_ops_generic(struct ixgbe_hw *hw);
 s32 ixgbe_init_hw_generic(struct ixgbe_hw *hw);
 s32 ixgbe_start_hw_generic(struct ixgbe_hw *hw);

drivers/net/ethernet/intel/ixgbe/ixgbe_type.h

@@ -1681,7 +1681,9 @@ enum {
 #define IXGBE_DEVICE_CAPS       0x2C
 #define IXGBE_SERIAL_NUMBER_MAC_ADDR 0x11
 #define IXGBE_PCIE_MSIX_82599_CAPS  0x72
+#define IXGBE_MAX_MSIX_VECTORS_82599	0x40
 #define IXGBE_PCIE_MSIX_82598_CAPS  0x62
+#define IXGBE_MAX_MSIX_VECTORS_82598	0x13
 
 /* MSI-X capability fields masks */
 #define IXGBE_PCIE_MSIX_TBL_SZ_MASK     0x7FF
@@ -2813,6 +2815,7 @@ struct ixgbe_mac_info {
 	u16                             wwnn_prefix;
 	/* prefix for World Wide Port Name (WWPN) */
 	u16                             wwpn_prefix;
+	u16				max_msix_vectors;
 #define IXGBE_MAX_MTA			128
 	u32				mta_shadow[IXGBE_MAX_MTA];
 	s32                             mc_filter_type;
@@ -2823,7 +2826,6 @@ struct ixgbe_mac_info {
 	u32				rx_pb_size;
 	u32                             max_tx_queues;
 	u32                             max_rx_queues;
-	u32                             max_msix_vectors;
 	u32                             orig_autoc;
 	u32                             orig_autoc2;
 	bool                            orig_link_settings_stored;