[PATCH 5.7 059/120] net/mlx5: Query PPS pin operational status before registering it

[Greg Kroah-Hartman]

From: Eran Ben Elisha <era...@mellanox.com>

[ Upstream commit ed56d749c366be269d58b29597392e4a0ae71c0a ]

In a special configuration, a ConnectX6-Dx pin pps-out might be activated
when driver is loaded. Fix the driver to always read the operational pin
mode when registering it, and advertise it accordingly.

Fixes: ee7f12205abc ("net/mlx5e: Implement 1PPS support")
Signed-off-by: Eran Ben Elisha <era...@mellanox.com>
Signed-off-by: Saeed Mahameed <sae...@mellanox.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 .../ethernet/mellanox/mlx5/core/lib/clock.c   | 34 ++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c 
b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
index 0267552b8a61b..1d9a5117f90b2 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
@@ -431,6 +431,38 @@ static const struct ptp_clock_info mlx5_ptp_clock_info = {
        .verify         = NULL,
 };
 
+static int mlx5_query_mtpps_pin_mode(struct mlx5_core_dev *mdev, u8 pin,
+                                    u32 *mtpps, u32 mtpps_size)
+{
+       u32 in[MLX5_ST_SZ_DW(mtpps_reg)] = {};
+
+       MLX5_SET(mtpps_reg, in, pin, pin);
+
+       return mlx5_core_access_reg(mdev, in, sizeof(in), mtpps,
+                                   mtpps_size, MLX5_REG_MTPPS, 0, 0);
+}
+
+static int mlx5_get_pps_pin_mode(struct mlx5_clock *clock, u8 pin)
+{
+       struct mlx5_core_dev *mdev = clock->mdev;
+       u32 out[MLX5_ST_SZ_DW(mtpps_reg)] = {};
+       u8 mode;
+       int err;
+
+       err = mlx5_query_mtpps_pin_mode(mdev, pin, out, sizeof(out));
+       if (err || !MLX5_GET(mtpps_reg, out, enable))
+               return PTP_PF_NONE;
+
+       mode = MLX5_GET(mtpps_reg, out, pin_mode);
+
+       if (mode == MLX5_PIN_MODE_IN)
+               return PTP_PF_EXTTS;
+       else if (mode == MLX5_PIN_MODE_OUT)
+               return PTP_PF_PEROUT;
+
+       return PTP_PF_NONE;
+}
+
 static int mlx5_init_pin_config(struct mlx5_clock *clock)
 {
        int i;
@@ -450,7 +482,7 @@ static int mlx5_init_pin_config(struct mlx5_clock *clock)
                         sizeof(clock->ptp_info.pin_config[i].name),
                         "mlx5_pps%d", i);
                clock->ptp_info.pin_config[i].index = i;
-               clock->ptp_info.pin_config[i].func = PTP_PF_NONE;
+               clock->ptp_info.pin_config[i].func = 
mlx5_get_pps_pin_mode(clock, i);
                clock->ptp_info.pin_config[i].chan = 0;
        }
 
-- 
2.25.1