1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/hwmon.c b/drivers/net/ethernet/mellanox/mlx5/core/hwmon.c
new file mode 100644
index 000000000000..353f81dccd1c
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/hwmon.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+// Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved
+
+#include <linux/hwmon.h>
+#include <linux/bitmap.h>
+#include <linux/mlx5/device.h>
+#include <linux/mlx5/mlx5_ifc.h>
+#include <linux/mlx5/port.h>
+#include "mlx5_core.h"
+#include "hwmon.h"
+
+#define CHANNELS_TYPE_NUM 2 /* chip channel and temp channel */
+#define CHIP_CONFIG_NUM 1
+
+/* module 0 is mapped to sensor_index 64 in MTMP register */
+#define to_mtmp_module_sensor_idx(idx) (64 + (idx))
+
+/* All temperatures retrieved in units of 0.125C. hwmon framework expect
+ * it in units of millidegrees C. Hence multiply values by 125.
+ */
+#define mtmp_temp_to_mdeg(temp) ((temp) * 125)
+
+struct temp_channel_desc {
+	u32 sensor_index;
+	char sensor_name[32];
+};
+
+/* chip_channel_config and channel_info arrays must be 0-terminated, hence + 1 */
+struct mlx5_hwmon {
+	struct mlx5_core_dev *mdev;
+	struct device *hwmon_dev;
+	struct hwmon_channel_info chip_info;
+	u32 chip_channel_config[CHIP_CONFIG_NUM + 1];
+	struct hwmon_channel_info temp_info;
+	u32 *temp_channel_config;
+	const struct hwmon_channel_info *channel_info[CHANNELS_TYPE_NUM + 1];
+	struct hwmon_chip_info chip;
+	struct temp_channel_desc *temp_channel_desc;
+	u32 asic_platform_scount;
+	u32 module_scount;
+};
+
+static int mlx5_hwmon_query_mtmp(struct mlx5_core_dev *mdev, u32 sensor_index, u32 *mtmp_out)
+{
+	u32 mtmp_in[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+
+	MLX5_SET(mtmp_reg, mtmp_in, sensor_index, sensor_index);
+
+	return mlx5_core_access_reg(mdev, mtmp_in,  sizeof(mtmp_in),
+				    mtmp_out, MLX5_ST_SZ_BYTES(mtmp_reg),
+				    MLX5_REG_MTMP, 0, 0);
+}
+
+static int mlx5_hwmon_reset_max_temp(struct mlx5_core_dev *mdev, int sensor_index)
+{
+	u32 mtmp_out[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+	u32 mtmp_in[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+
+	MLX5_SET(mtmp_reg, mtmp_in, sensor_index, sensor_index);
+	MLX5_SET(mtmp_reg, mtmp_in, mtr, 1);
+
+	return mlx5_core_access_reg(mdev, mtmp_in,  sizeof(mtmp_in),
+				    mtmp_out, sizeof(mtmp_out),
+				    MLX5_REG_MTMP, 0, 0);
+}
+
+static int mlx5_hwmon_enable_max_temp(struct mlx5_core_dev *mdev, int sensor_index)
+{
+	u32 mtmp_out[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+	u32 mtmp_in[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+	int err;
+
+	err = mlx5_hwmon_query_mtmp(mdev, sensor_index, mtmp_in);
+	if (err)
+		return err;
+
+	MLX5_SET(mtmp_reg, mtmp_in, mte, 1);
+	return mlx5_core_access_reg(mdev, mtmp_in,  sizeof(mtmp_in),
+				    mtmp_out, sizeof(mtmp_out),
+				    MLX5_REG_MTMP, 0, 1);
+}
+
+static int mlx5_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+			   int channel, long *val)
+{
+	struct mlx5_hwmon *hwmon = dev_get_drvdata(dev);
+	u32 mtmp_out[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+	int err;
+
+	if (type != hwmon_temp)
+		return -EOPNOTSUPP;
+
+	err = mlx5_hwmon_query_mtmp(hwmon->mdev, hwmon->temp_channel_desc[channel].sensor_index,
+				    mtmp_out);
+	if (err)
+		return err;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		*val = mtmp_temp_to_mdeg(MLX5_GET(mtmp_reg, mtmp_out, temperature));
+		return 0;
+	case hwmon_temp_highest:
+		*val = mtmp_temp_to_mdeg(MLX5_GET(mtmp_reg, mtmp_out, max_temperature));
+		return 0;
+	case hwmon_temp_crit:
+		*val = mtmp_temp_to_mdeg(MLX5_GET(mtmp_reg, mtmp_out, temp_threshold_hi));
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int mlx5_hwmon_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+			    int channel, long val)
+{
+	struct mlx5_hwmon *hwmon = dev_get_drvdata(dev);
+
+	if (type != hwmon_temp || attr != hwmon_temp_reset_history)
+		return -EOPNOTSUPP;
+
+	return mlx5_hwmon_reset_max_temp(hwmon->mdev,
+				hwmon->temp_channel_desc[channel].sensor_index);
+}
+
+static umode_t mlx5_hwmon_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr,
+				     int channel)
+{
+	if (type != hwmon_temp)
+		return 0;
+
+	switch (attr) {
+	case hwmon_temp_input:
+	case hwmon_temp_highest:
+	case hwmon_temp_crit:
+	case hwmon_temp_label:
+		return 0444;
+	case hwmon_temp_reset_history:
+		return 0200;
+	default:
+		return 0;
+	}
+}
+
+static int mlx5_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+				  int channel, const char **str)
+{
+	struct mlx5_hwmon *hwmon = dev_get_drvdata(dev);
+
+	if (type != hwmon_temp || attr != hwmon_temp_label)
+		return -EOPNOTSUPP;
+
+	*str = (const char *)hwmon->temp_channel_desc[channel].sensor_name;
+	return 0;
+}
+
+static const struct hwmon_ops mlx5_hwmon_ops = {
+	.read = mlx5_hwmon_read,
+	.read_string = mlx5_hwmon_read_string,
+	.is_visible = mlx5_hwmon_is_visible,
+	.write = mlx5_hwmon_write,
+};
+
+static int mlx5_hwmon_init_channels_names(struct mlx5_hwmon *hwmon)
+{
+	u32 i;
+
+	for (i = 0; i < hwmon->asic_platform_scount + hwmon->module_scount; i++) {
+		u32 mtmp_out[MLX5_ST_SZ_DW(mtmp_reg)] = {};
+		char *sensor_name;
+		int err;
+
+		err = mlx5_hwmon_query_mtmp(hwmon->mdev, hwmon->temp_channel_desc[i].sensor_index,
+					    mtmp_out);
+		if (err)
+			return err;
+
+		sensor_name = MLX5_ADDR_OF(mtmp_reg, mtmp_out, sensor_name_hi);
+		if (!*sensor_name) {
+			snprintf(hwmon->temp_channel_desc[i].sensor_name,
+				 sizeof(hwmon->temp_channel_desc[i].sensor_name), "sensor%u",
+				 hwmon->temp_channel_desc[i].sensor_index);
+			continue;
+		}
+
+		memcpy(&hwmon->temp_channel_desc[i].sensor_name, sensor_name,
+		       MLX5_FLD_SZ_BYTES(mtmp_reg, sensor_name_hi) +
+		       MLX5_FLD_SZ_BYTES(mtmp_reg, sensor_name_lo));
+	}
+
+	return 0;
+}
+
+static int mlx5_hwmon_get_module_sensor_index(struct mlx5_core_dev *mdev, u32 *module_index)
+{
+	int module_num;
+	int err;
+
+	err = mlx5_query_module_num(mdev, &module_num);
+	if (err)
+		return err;
+
+	*module_index = to_mtmp_module_sensor_idx(module_num);
+
+	return 0;
+}
+
+static int mlx5_hwmon_init_sensors_indexes(struct mlx5_hwmon *hwmon, u64 sensor_map)
+{
+	DECLARE_BITMAP(smap, BITS_PER_TYPE(sensor_map));
+	unsigned long bit_pos;
+	int err = 0;
+	int i = 0;
+
+	bitmap_from_u64(smap, sensor_map);
+
+	for_each_set_bit(bit_pos, smap, BITS_PER_TYPE(sensor_map)) {
+		hwmon->temp_channel_desc[i].sensor_index = bit_pos;
+		i++;
+	}
+
+	if (hwmon->module_scount)
+		err = mlx5_hwmon_get_module_sensor_index(hwmon->mdev,
+							 &hwmon->temp_channel_desc[i].sensor_index);
+
+	return err;
+}
+
+static void mlx5_hwmon_channel_info_init(struct mlx5_hwmon *hwmon)
+{
+	int i;
+
+	hwmon->channel_info[0] = &hwmon->chip_info;
+	hwmon->channel_info[1] = &hwmon->temp_info;
+
+	hwmon->chip_channel_config[0] = HWMON_C_REGISTER_TZ;
+	hwmon->chip_info.config = (const u32 *)hwmon->chip_channel_config;
+	hwmon->chip_info.type = hwmon_chip;
+
+	for (i = 0; i < hwmon->asic_platform_scount + hwmon->module_scount; i++)
+		hwmon->temp_channel_config[i] = HWMON_T_INPUT | HWMON_T_HIGHEST | HWMON_T_CRIT |
+					     HWMON_T_RESET_HISTORY | HWMON_T_LABEL;
+
+	hwmon->temp_info.config = (const u32 *)hwmon->temp_channel_config;
+	hwmon->temp_info.type = hwmon_temp;
+}
+
+static int mlx5_hwmon_is_module_mon_cap(struct mlx5_core_dev *mdev, bool *mon_cap)
+{
+	u32 mtmp_out[MLX5_ST_SZ_DW(mtmp_reg)];
+	u32 module_index;
+	int err;
+
+	err = mlx5_hwmon_get_module_sensor_index(mdev, &module_index);
+	if (err)
+		return err;
+
+	err = mlx5_hwmon_query_mtmp(mdev, module_index, mtmp_out);
+	if (err)
+		return err;
+
+	if (MLX5_GET(mtmp_reg, mtmp_out, temperature))
+		*mon_cap = true;
+
+	return 0;
+}
+
+static int mlx5_hwmon_get_sensors_count(struct mlx5_core_dev *mdev, u32 *asic_platform_scount)
+{
+	u32 mtcap_out[MLX5_ST_SZ_DW(mtcap_reg)] = {};
+	u32 mtcap_in[MLX5_ST_SZ_DW(mtcap_reg)] = {};
+	int err;
+
+	err = mlx5_core_access_reg(mdev, mtcap_in,  sizeof(mtcap_in),
+				   mtcap_out, sizeof(mtcap_out),
+				   MLX5_REG_MTCAP, 0, 0);
+	if (err)
+		return err;
+
+	*asic_platform_scount = MLX5_GET(mtcap_reg, mtcap_out, sensor_count);
+
+	return 0;
+}
+
+static void mlx5_hwmon_free(struct mlx5_hwmon *hwmon)
+{
+	if (!hwmon)
+		return;
+
+	kfree(hwmon->temp_channel_config);
+	kfree(hwmon->temp_channel_desc);
+	kfree(hwmon);
+}
+
+static struct mlx5_hwmon *mlx5_hwmon_alloc(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_hwmon *hwmon;
+	bool mon_cap = false;
+	u32 sensors_count;
+	int err;
+
+	hwmon = kzalloc(sizeof(*mdev->hwmon), GFP_KERNEL);
+	if (!hwmon)
+		return ERR_PTR(-ENOMEM);
+
+	err = mlx5_hwmon_get_sensors_count(mdev, &hwmon->asic_platform_scount);
+	if (err)
+		goto err_free_hwmon;
+
+	/* check if module sensor has thermal mon cap. if yes, allocate channel desc for it */
+	err = mlx5_hwmon_is_module_mon_cap(mdev, &mon_cap);
+	if (err)
+		goto err_free_hwmon;
+
+	hwmon->module_scount = mon_cap ? 1 : 0;
+	sensors_count = hwmon->asic_platform_scount + hwmon->module_scount;
+	hwmon->temp_channel_desc = kcalloc(sensors_count, sizeof(*hwmon->temp_channel_desc),
+					   GFP_KERNEL);
+	if (!hwmon->temp_channel_desc) {
+		err = -ENOMEM;
+		goto err_free_hwmon;
+	}
+
+	/* sensors configuration values array, must be 0-terminated hence, + 1 */
+	hwmon->temp_channel_config = kcalloc(sensors_count + 1, sizeof(*hwmon->temp_channel_config),
+					     GFP_KERNEL);
+	if (!hwmon->temp_channel_config) {
+		err = -ENOMEM;
+		goto err_free_temp_channel_desc;
+	}
+
+	hwmon->mdev = mdev;
+
+	return hwmon;
+
+err_free_temp_channel_desc:
+	kfree(hwmon->temp_channel_desc);
+err_free_hwmon:
+	kfree(hwmon);
+	return ERR_PTR(err);
+}
+
+static int mlx5_hwmon_dev_init(struct mlx5_hwmon *hwmon)
+{
+	u32 mtcap_out[MLX5_ST_SZ_DW(mtcap_reg)] = {};
+	u32 mtcap_in[MLX5_ST_SZ_DW(mtcap_reg)] = {};
+	int err;
+	int i;
+
+	err =  mlx5_core_access_reg(hwmon->mdev, mtcap_in,  sizeof(mtcap_in),
+				    mtcap_out, sizeof(mtcap_out),
+				    MLX5_REG_MTCAP, 0, 0);
+	if (err)
+		return err;
+
+	mlx5_hwmon_channel_info_init(hwmon);
+	mlx5_hwmon_init_sensors_indexes(hwmon, MLX5_GET64(mtcap_reg, mtcap_out, sensor_map));
+	err = mlx5_hwmon_init_channels_names(hwmon);
+	if (err)
+		return err;
+
+	for (i = 0; i < hwmon->asic_platform_scount + hwmon->module_scount; i++) {
+		err = mlx5_hwmon_enable_max_temp(hwmon->mdev,
+						 hwmon->temp_channel_desc[i].sensor_index);
+		if (err)
+			return err;
+	}
+
+	hwmon->chip.ops = &mlx5_hwmon_ops;
+	hwmon->chip.info = (const struct hwmon_channel_info **)hwmon->channel_info;
+
+	return 0;
+}
+
+int mlx5_hwmon_dev_register(struct mlx5_core_dev *mdev)
+{
+	struct device *dev = mdev->device;
+	struct mlx5_hwmon *hwmon;
+	int err;
+
+	if (!MLX5_CAP_MCAM_REG(mdev, mtmp))
+		return 0;
+
+	hwmon = mlx5_hwmon_alloc(mdev);
+	if (IS_ERR(hwmon))
+		return PTR_ERR(hwmon);
+
+	err = mlx5_hwmon_dev_init(hwmon);
+	if (err)
+		goto err_free_hwmon;
+
+	hwmon->hwmon_dev = hwmon_device_register_with_info(dev, "mlx5",
+							   hwmon,
+							   &hwmon->chip,
+							   NULL);
+	if (IS_ERR(hwmon->hwmon_dev)) {
+		err = PTR_ERR(hwmon->hwmon_dev);
+		goto err_free_hwmon;
+	}
+
+	mdev->hwmon = hwmon;
+	return 0;
+
+err_free_hwmon:
+	mlx5_hwmon_free(hwmon);
+	return err;
+}
+
+void mlx5_hwmon_dev_unregister(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_hwmon *hwmon = mdev->hwmon;
+
+	if (!hwmon)
+		return;
+
+	hwmon_device_unregister(hwmon->hwmon_dev);
+	mlx5_hwmon_free(hwmon);
+	mdev->hwmon = NULL;
+}