net/mlx5e: Use pcie_bandwidth_available() to compute bandwidth

Use the new pci_bandwidth_available() function to calculate maximum
available bandwidth through the PCI chain instead of computing it ourselves
with mlx5e_get_pci_bw().

This is used to detect when the device is capable of more bandwidth than is
available in the current slot.  The driver may adjust compression settings
accordingly.

Note that pci_bandwidth_available() accounts for PCIe encoding overhead, so
it is more accurate than mlx5e_get_pci_bw() was.

Signed-off-by: Tal Gilboa <talgi@mellanox.com>
[bhelgaas: remove mlx5e_get_pci_bw() wrapper altogether]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>

1 files changed, 1 insertions, 31 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 47bab842c5ee..93291ec4a3d1 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -3864,36 +3864,6 @@ void mlx5e_build_default_indir_rqt(u32 *indirection_rqt, int len,
                 indirection_rqt[i] = i % num_channels;
 }
 
-static int mlx5e_get_pci_bw(struct mlx5_core_dev *mdev, u32 *pci_bw)
-{
-        enum pcie_link_width width;
-        enum pci_bus_speed speed;
-        int err = 0;
-
-        err = pcie_get_minimum_link(mdev->pdev, &speed, &width);
-        if (err)
-                return err;
-
-        if (speed == PCI_SPEED_UNKNOWN || width == PCIE_LNK_WIDTH_UNKNOWN)
-                return -EINVAL;
-
-        switch (speed) {
-        case PCIE_SPEED_2_5GT:
-                *pci_bw = 2500 * width;
-                break;
-        case PCIE_SPEED_5_0GT:
-                *pci_bw = 5000 * width;
-                break;
-        case PCIE_SPEED_8_0GT:
-                *pci_bw = 8000 * width;
-                break;
-        default:
-                return -EINVAL;
-        }
-
-        return 0;
-}
-
 static bool cqe_compress_heuristic(u32 link_speed, u32 pci_bw)
 {
         return (link_speed && pci_bw &&
@@ -3979,7 +3949,7 @@ void mlx5e_build_nic_params(struct mlx5_core_dev *mdev,
         params->num_tc       = 1;
 
         mlx5e_get_max_linkspeed(mdev, &link_speed);
-        mlx5e_get_pci_bw(mdev, &pci_bw);
+        pci_bw = pcie_bandwidth_available(mdev->pdev, NULL, NULL, NULL);
         mlx5_core_dbg(mdev, "Max link speed = %d, PCI BW = %d\n",
                       link_speed, pci_bw);