[RFC PATCH V4 net-next 3/5] net/mlx5: Implement get_module_eeprom_by_page()

[Moshe Shemesh <moshe@nvidia.com>]

From: Vladyslav Tarasiuk <vladyslavt@nvidia.com>

Implement ethtool_ops::get_module_eeprom_by_page() to enable
support of new SFP standards.

Signed-off-by: Vladyslav Tarasiuk <vladyslavt@nvidia.com>
---
 .../ethernet/mellanox/mlx5/core/en_ethtool.c  | 44 +++++++++++++++++++
 .../net/ethernet/mellanox/mlx5/core/port.c    | 33 ++++++++++++++
 include/linux/mlx5/port.h                     |  2 +
 3 files changed, 79 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index abdf721bb264..7f413f7bd1d3 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -1769,6 +1769,49 @@ static int mlx5e_get_module_eeprom(struct net_device *netdev,
 	return 0;
 }
 
+static int mlx5e_get_module_eeprom_by_page(struct net_device *netdev,
+					   const struct ethtool_module_eeprom *page_data,
+					   struct netlink_ext_ack *extack)
+{
+	struct mlx5e_priv *priv = netdev_priv(netdev);
+	struct mlx5_module_eeprom_query_params query;
+	struct mlx5_core_dev *mdev = priv->mdev;
+	u8 *data = page_data->data;
+	int size_read;
+	int i = 0;
+
+	if (!page_data->length)
+		return -EINVAL;
+
+	memset(data, 0, page_data->length);
+
+	query.offset = page_data->offset;
+	query.i2c_address = page_data->i2c_address;
+	query.bank = page_data->bank;
+	query.page = page_data->page;
+	while (i < page_data->length) {
+		query.size = page_data->length - i;
+		size_read = mlx5_query_module_eeprom_by_page(mdev, &query, data + i);
+
+		/* Done reading, return how many bytes was read */
+		if (!size_read)
+			return i;
+
+		if (size_read == -EINVAL)
+			return -EINVAL;
+		if (size_read < 0) {
+			netdev_err(priv->netdev, "%s: mlx5_query_module_eeprom_by_page failed:0x%x\n",
+				   __func__, size_read);
+			return i;
+		}
+
+		i += size_read;
+		query.offset += size_read;
+	}
+
+	return i;
+}
+
 int mlx5e_ethtool_flash_device(struct mlx5e_priv *priv,
 			       struct ethtool_flash *flash)
 {
@@ -2148,6 +2191,7 @@ const struct ethtool_ops mlx5e_ethtool_ops = {
 	.set_wol	   = mlx5e_set_wol,
 	.get_module_info   = mlx5e_get_module_info,
 	.get_module_eeprom = mlx5e_get_module_eeprom,
+	.get_module_eeprom_by_page = mlx5e_get_module_eeprom_by_page,
 	.flash_device      = mlx5e_flash_device,
 	.get_priv_flags    = mlx5e_get_priv_flags,
 	.set_priv_flags    = mlx5e_set_priv_flags,
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/port.c b/drivers/net/ethernet/mellanox/mlx5/core/port.c
index 9b9f870d67a4..114214728e32 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/port.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/port.c
@@ -428,6 +428,39 @@ int mlx5_query_module_eeprom(struct mlx5_core_dev *dev,
 }
 EXPORT_SYMBOL_GPL(mlx5_query_module_eeprom);
 
+int mlx5_query_module_eeprom_by_page(struct mlx5_core_dev *dev,
+				     struct mlx5_module_eeprom_query_params *params,
+				     u8 *data)
+{
+	u8 module_id;
+	int err;
+
+	err = mlx5_query_module_num(dev, &params->module_number);
+	if (err)
+		return err;
+
+	err = mlx5_query_module_id(dev, params->module_number, &module_id);
+	if (err)
+		return err;
+
+	if (module_id != MLX5_MODULE_ID_SFP &&
+	    module_id != MLX5_MODULE_ID_QSFP &&
+	    module_id != MLX5_MODULE_ID_QSFP28 &&
+	    module_id != MLX5_MODULE_ID_QSFP_PLUS) {
+		mlx5_core_err(dev, "Module ID not recognized: 0x%x\n", module_id);
+		return -EINVAL;
+	}
+
+	if (params->i2c_address != MLX5_I2C_ADDR_HIGH &&
+	    params->i2c_address != MLX5_I2C_ADDR_LOW) {
+		mlx5_core_err(dev, "I2C address not recognized: 0x%x\n", params->i2c_address);
+		return -EINVAL;
+	}
+
+	return mlx5_query_mcia(dev, params, data);
+}
+EXPORT_SYMBOL_GPL(mlx5_query_module_eeprom_by_page);
+
 static int mlx5_query_port_pvlc(struct mlx5_core_dev *dev, u32 *pvlc,
 				int pvlc_size,  u8 local_port)
 {
diff --git a/include/linux/mlx5/port.h b/include/linux/mlx5/port.h
index 90b87aa82db3..58d56adb9842 100644
--- a/include/linux/mlx5/port.h
+++ b/include/linux/mlx5/port.h
@@ -209,6 +209,8 @@ void mlx5_query_port_fcs(struct mlx5_core_dev *mdev, bool *supported,
 			 bool *enabled);
 int mlx5_query_module_eeprom(struct mlx5_core_dev *dev,
 			     u16 offset, u16 size, u8 *data);
+int mlx5_query_module_eeprom_by_page(struct mlx5_core_dev *dev,
+				     struct mlx5_module_eeprom_query_params *params, u8 *data);
 
 int mlx5_query_port_dcbx_param(struct mlx5_core_dev *mdev, u32 *out);
 int mlx5_set_port_dcbx_param(struct mlx5_core_dev *mdev, u32 *in);
-- 
2.18.2