6.8-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ido Schimmel idosch@nvidia.com
[ Upstream commit 773501d01e6bc3f2557882a25679392d982d5f3e ]
The driver queries the Management Capabilities Mask (MCAM) register during initialization to understand if a new and deeper reset flow is supported.
However, not all firmware versions support this register, leading to the driver failing to load.
Fix by treating an error in the register query as an indication that the feature is not supported.
Fixes: f257c73e5356 ("mlxsw: pci: Add support for new reset flow") Reported-by: Tim 'mithro' Ansell me@mith.ro Signed-off-by: Ido Schimmel idosch@nvidia.com Reviewed-by: Petr Machata petrm@nvidia.com Reviewed-by: Simon Horman horms@kernel.org Reviewed-by: Kalesh AP kalesh-anakkur.purayil@broadcom.com Signed-off-by: Petr Machata petrm@nvidia.com Link: https://lore.kernel.org/r/ee968c49d53bac96a4c66d1b09ebbd097d81aca5.171344609... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlxsw/pci.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/pci.c b/drivers/net/ethernet/mellanox/mlxsw/pci.c index af99bf17eb36d..f42a1b1c93687 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/pci.c +++ b/drivers/net/ethernet/mellanox/mlxsw/pci.c @@ -1530,7 +1530,7 @@ mlxsw_pci_reset(struct mlxsw_pci *mlxsw_pci, const struct pci_device_id *id) { struct pci_dev *pdev = mlxsw_pci->pdev; char mcam_pl[MLXSW_REG_MCAM_LEN]; - bool pci_reset_supported; + bool pci_reset_supported = false; u32 sys_status; int err;
@@ -1548,11 +1548,9 @@ mlxsw_pci_reset(struct mlxsw_pci *mlxsw_pci, const struct pci_device_id *id) mlxsw_reg_mcam_pack(mcam_pl, MLXSW_REG_MCAM_FEATURE_GROUP_ENHANCED_FEATURES); err = mlxsw_reg_query(mlxsw_pci->core, MLXSW_REG(mcam), mcam_pl); - if (err) - return err; - - mlxsw_reg_mcam_unpack(mcam_pl, MLXSW_REG_MCAM_PCI_RESET, - &pci_reset_supported); + if (!err) + mlxsw_reg_mcam_unpack(mcam_pl, MLXSW_REG_MCAM_PCI_RESET, + &pci_reset_supported);
if (pci_reset_supported) { pci_dbg(pdev, "Starting PCI reset flow\n");