From: Tal Gilboa <talgi@mellanox.com>
Date: Fri, 30 Mar 2018 09:01:51 -0500
Subject: net/mlx5e: Use pcie_bandwidth_available() to compute bandwidth
Patch-mainline: v4.17-rc1
Git-commit: 33523a361307c097a8a23f3549cb485db5fba6c5
References: bsc#1103990 FATE#326006
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>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 36 +---------------------
1 file changed, 3 insertions(+), 33 deletions(-)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -4033,45 +4033,15 @@ void mlx5e_build_default_indir_rqt(u32 *
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 slow_pci_heuristic(struct mlx5_core_dev *mdev)
{
u32 link_speed = 0;
u32 pci_bw = 0;
mlx5e_get_max_linkspeed(mdev, &link_speed);
- mlx5e_get_pci_bw(mdev, &pci_bw);
- mlx5_core_dbg_once(mdev, "Max link speed = %d, PCI BW = %d\n",
- link_speed, 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);
#define MLX5E_SLOW_PCI_RATIO (2)