1 files changed, 108 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/thermal.c b/drivers/net/ethernet/mellanox/mlx5/core/thermal.c
new file mode 100644
index 000000000000..e47fa6fb836f
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/thermal.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+// Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES.
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/thermal.h>
+#include <linux/err.h>
+#include <linux/mlx5/driver.h>
+#include "mlx5_core.h"
+#include "thermal.h"
+
+#define MLX5_THERMAL_POLL_INT_MSEC	1000
+#define MLX5_THERMAL_NUM_TRIPS		0
+#define MLX5_THERMAL_ASIC_SENSOR_INDEX	0
+
+/* Bit string indicating the writeablility of trip points if any */
+#define MLX5_THERMAL_TRIP_MASK	(BIT(MLX5_THERMAL_NUM_TRIPS) - 1)
+
+struct mlx5_thermal {
+	struct mlx5_core_dev *mdev;
+	struct thermal_zone_device *tzdev;
+};
+
+static int mlx5_thermal_get_mtmp_temp(struct mlx5_core_dev *mdev, u32 id, int *p_temp)
+{
+	u32 mtmp_out[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+	u32 mtmp_in[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+	int err;
+
+	MLX5_SET(mtmp_reg, mtmp_in, sensor_index, id);
+
+	err = mlx5_core_access_reg(mdev, mtmp_in,  sizeof(mtmp_in),
+				   mtmp_out, sizeof(mtmp_out),
+				   MLX5_REG_MTMP, 0, 0);
+
+	if (err)
+		return err;
+
+	*p_temp = MLX5_GET(mtmp_reg, mtmp_out, temperature);
+
+	return 0;
+}
+
+static int mlx5_thermal_get_temp(struct thermal_zone_device *tzdev,
+				 int *p_temp)
+{
+	struct mlx5_thermal *thermal = tzdev->devdata;
+	struct mlx5_core_dev *mdev = thermal->mdev;
+	int err;
+
+	err = mlx5_thermal_get_mtmp_temp(mdev, MLX5_THERMAL_ASIC_SENSOR_INDEX, p_temp);
+
+	if (err)
+		return err;
+
+	/* The unit of temp returned is in 0.125 C. The thermal
+	 * framework expects the value in 0.001 C.
+	 */
+	*p_temp *= 125;
+
+	return 0;
+}
+
+static struct thermal_zone_device_ops mlx5_thermal_ops = {
+	.get_temp = mlx5_thermal_get_temp,
+};
+
+int mlx5_thermal_init(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_thermal *thermal;
+	struct thermal_zone_device *tzd;
+	const char *data = "mlx5";
+
+	tzd = thermal_zone_get_zone_by_name(data);
+	if (!IS_ERR(tzd))
+		return 0;
+
+	thermal = kzalloc(sizeof(*thermal), GFP_KERNEL);
+	if (!thermal)
+		return -ENOMEM;
+
+	thermal->mdev = mdev;
+	thermal->tzdev = thermal_zone_device_register(data,
+						      MLX5_THERMAL_NUM_TRIPS,
+						      MLX5_THERMAL_TRIP_MASK,
+						      thermal,
+						      &mlx5_thermal_ops,
+						      NULL, 0, MLX5_THERMAL_POLL_INT_MSEC);
+	if (IS_ERR(thermal->tzdev)) {
+		dev_err(mdev->device, "Failed to register thermal zone device (%s) %ld\n",
+			data, PTR_ERR(thermal->tzdev));
+		kfree(thermal);
+		return -EINVAL;
+	}
+
+	mdev->thermal = thermal;
+	return 0;
+}
+
+void mlx5_thermal_uninit(struct mlx5_core_dev *mdev)
+{
+	if (!mdev->thermal)
+		return;
+
+	thermal_zone_device_unregister(mdev->thermal->tzdev);
+	kfree(mdev->thermal);
+}