mlxsw: spectrum_buffers: Tweak SBMM configuration

The SBMM register configures shared buffer allocation and settings for
MC packets according to switch priority. The recommended values are no
reserved buffer and alpha of 1/4, which corresponds to buf_max of 6.
Update mlxsw_sp_sb_mms accordingly.
Signed-off-by: NPetr Machata <petrm@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c

@@ -566,21 +566,21 @@ struct mlxsw_sp_sb_mm {
 	}
 
 static const struct mlxsw_sp_sb_mm mlxsw_sp_sb_mms[] = {
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
-	MLXSW_SP_SB_MM(20000, 0xff, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
+	MLXSW_SP_SB_MM(0, 6, 4),
 };
 
 #define MLXSW_SP_SB_MMS_LEN ARRAY_SIZE(mlxsw_sp_sb_mms)