net/mlx5: Query the maximum MCIA register read size from firmware

The MCIA register supports either 12 or 32 dwords, use the correct value
by querying the capability from the MCAM register.

Signed-off-by: Gal Pressman <[email protected]>
Reviewed-by: Maxim Mikityanskiy <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>

Author: gal-pressman

drivers/net/ethernet/mellanox/mlx5/core/port.c

@@ -365,6 +365,12 @@ static void mlx5_sfp_eeprom_params_set(u16 *i2c_addr, int *page_num, u16 *offset
 	*offset -= MLX5_EEPROM_PAGE_LENGTH;
 }
 
+static int mlx5_mcia_max_bytes(struct mlx5_core_dev *dev)
+{
+	/* mcia supports either 12 dwords or 32 dwords */
+	return (MLX5_CAP_MCAM_FEATURE(dev, mcia_32dwords) ? 32 : 12) * sizeof(u32);
+}
+
 static int mlx5_query_mcia(struct mlx5_core_dev *dev,
 			   struct mlx5_module_eeprom_query_params *params, u8 *data)
 {
@@ -374,7 +380,7 @@ static int mlx5_query_mcia(struct mlx5_core_dev *dev,
 	void *ptr;
 	u16 size;
 
-	size = min_t(int, params->size, MLX5_EEPROM_MAX_BYTES);
+	size = min_t(int, params->size, mlx5_mcia_max_bytes(dev));
 
 	MLX5_SET(mcia_reg, in, l, 0);
 	MLX5_SET(mcia_reg, in, size, size);

include/linux/mlx5/mlx5_ifc.h

@@ -9691,7 +9691,9 @@ struct mlx5_ifc_pcam_reg_bits {
 };
 
 struct mlx5_ifc_mcam_enhanced_features_bits {
-	u8         reserved_at_0[0x6a];
+	u8         reserved_at_0[0x5d];
+	u8         mcia_32dwords[0x1];
+	u8         reserved_at_5e[0xc];
 	u8         reset_state[0x1];
 	u8         ptpcyc2realtime_modify[0x1];
 	u8         reserved_at_6c[0x2];

include/linux/mlx5/port.h

@@ -56,7 +56,6 @@ enum mlx5_an_status {
 	MLX5_AN_LINK_DOWN   = 4,
 };
 
-#define MLX5_EEPROM_MAX_BYTES			32
 #define MLX5_EEPROM_IDENTIFIER_BYTE_MASK	0x000000ff
 #define MLX5_I2C_ADDR_LOW		0x50
 #define MLX5_I2C_ADDR_HIGH		0x51