mlxsw: spectrum_buffers: Allow an infinite maximum for per-TC pool limit

The SBCM register configures the shared buffer configuration according
to port and TC. So far all pools have had a dynamic size, where the
infinite size is easy to express by using max_buff of 0xff. However the
MC pool should be configured with static size, and the infinite size
thus needs to be set using the field SBCM.infi_max.

Therefore add the field infi_max to the SBCM register and to
mlxsw_reg_sbcm_pack(). Extend mlxsw_sp_sb_cm_write() to handle infinite
sizes as well. Report infinite pool limits as if the limit actually were
the total shared buffer size.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlxsw/reg.h b/drivers/net/ethernet/mellanox/mlxsw/reg.h
index 694f6a4..df81e0a 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/reg.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/reg.h
@@ -8418,6 +8418,12 @@ MLXSW_ITEM32(reg, sbcm, min_buff, 0x18, 0, 24);
 #define MLXSW_REG_SBXX_DYN_MAX_BUFF_MIN 1
 #define MLXSW_REG_SBXX_DYN_MAX_BUFF_MAX 14
 
+/* reg_sbcm_infi_max
+ * Max buffer is infinite.
+ * Access: RW
+ */
+MLXSW_ITEM32(reg, sbcm, infi_max, 0x1C, 31, 1);
+
 /* reg_sbcm_max_buff
  * When the pool associated to the port-pg/tclass is configured to
  * static, Maximum buffer size for the limiter configured in cells.
@@ -8427,6 +8433,7 @@ MLXSW_ITEM32(reg, sbcm, min_buff, 0x18, 0, 24);
  * 0: 0
  * i: (1/128)*2^(i-1), for i=1..14
  * 0xFF: Infinity
+ * Reserved when infi_max = 1.
  * Access: RW
  */
 MLXSW_ITEM32(reg, sbcm, max_buff, 0x1C, 0, 24);
@@ -8439,7 +8446,8 @@ MLXSW_ITEM32(reg, sbcm, pool, 0x24, 0, 4);
 
 static inline void mlxsw_reg_sbcm_pack(char *payload, u8 local_port, u8 pg_buff,
                                       enum mlxsw_reg_sbxx_dir dir,
-                                      u32 min_buff, u32 max_buff, u8 pool)
+                                      u32 min_buff, u32 max_buff,
+                                      bool infi_max, u8 pool)
 {
        MLXSW_REG_ZERO(sbcm, payload);
        mlxsw_reg_sbcm_local_port_set(payload, local_port);
@@ -8447,6 +8455,7 @@ static inline void mlxsw_reg_sbcm_pack(char *payload, u8 local_port, u8 pg_buff,
        mlxsw_reg_sbcm_dir_set(payload, dir);
        mlxsw_reg_sbcm_min_buff_set(payload, min_buff);
        mlxsw_reg_sbcm_max_buff_set(payload, max_buff);
+       mlxsw_reg_sbcm_infi_max_set(payload, infi_max);
        mlxsw_reg_sbcm_pool_set(payload, pool);
 }
 

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
index 646022f..de51f56 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
@@ -142,20 +142,24 @@ static int mlxsw_sp_sb_pr_write(struct mlxsw_sp *mlxsw_sp, u16 pool_index,
 
 static int mlxsw_sp_sb_cm_write(struct mlxsw_sp *mlxsw_sp, u8 local_port,
                                u8 pg_buff, u32 min_buff, u32 max_buff,
-                               u16 pool_index)
+                               bool infi_max, u16 pool_index)
 {
        const struct mlxsw_sp_sb_pool_des *des =
                &mlxsw_sp_sb_pool_dess[pool_index];
        char sbcm_pl[MLXSW_REG_SBCM_LEN];
+       struct mlxsw_sp_sb_cm *cm;
        int err;
 
        mlxsw_reg_sbcm_pack(sbcm_pl, local_port, pg_buff, des->dir,
-                           min_buff, max_buff, des->pool);
+                           min_buff, max_buff, infi_max, des->pool);
        err = mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(sbcm), sbcm_pl);
        if (err)
                return err;
+
        if (mlxsw_sp_sb_cm_exists(pg_buff, des->dir)) {
-               struct mlxsw_sp_sb_cm *cm;
+               if (infi_max)
+                       max_buff = mlxsw_sp_bytes_cells(mlxsw_sp,
+                                                       mlxsw_sp->sb->sb_size);
 
                cm = mlxsw_sp_sb_cm_get(mlxsw_sp, local_port, pg_buff,
                                        des->dir);
@@ -451,9 +455,14 @@ static int __mlxsw_sp_sb_cms_init(struct mlxsw_sp *mlxsw_sp, u8 local_port,
                 * therefore 'max_buff' isn't specified in cells.
                 */
                min_buff = mlxsw_sp_bytes_cells(mlxsw_sp, cm->min_buff);
-               err = mlxsw_sp_sb_cm_write(mlxsw_sp, local_port, i,
-                                          min_buff, cm->max_buff,
-                                          cm->pool_index);
+               if (cm->max_buff == MLXSW_SP_SB_INFI)
+                       err = mlxsw_sp_sb_cm_write(mlxsw_sp, local_port, i,
+                                                  min_buff, 0,
+                                                  true, cm->pool_index);
+               else
+                       err = mlxsw_sp_sb_cm_write(mlxsw_sp, local_port, i,
+                                                  min_buff, cm->max_buff,
+                                                  false, cm->pool_index);
                if (err)
                        return err;
        }
@@ -813,7 +822,7 @@ int mlxsw_sp_sb_tc_pool_bind_set(struct mlxsw_core_port *mlxsw_core_port,
                return err;
 
        return mlxsw_sp_sb_cm_write(mlxsw_sp, local_port, pg_buff,
-                                   0, max_buff, pool_index);
+                                   0, max_buff, false, pool_index);
 }
 
 #define MASKED_COUNT_MAX \