From: Shalom Toledo <shalomt@mellanox.com>
Date: Mon, 16 Sep 2019 18:04:22 +0300
Subject: mlxsw: spectrum_buffers: Add the ability to query the CPU port's
 shared buffer
Patch-mainline: v5.4-rc1
Git-commit: a759ab6dacd0dd8e27f60f19bb92c2201db213fb
References: bsc#1154488

While debugging packet loss towards the CPU, it is useful to be able to
query the CPU port's shared buffer quotas and occupancy.

Since the CPU port has no ingress buffers, all the shared buffers ingress
information will be cleared.

Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c |   41 +++++++++++++----
 1 file changed, 33 insertions(+), 8 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
@@ -250,6 +250,10 @@ static int mlxsw_sp_sb_pm_occ_clear(stru
 		&mlxsw_sp->sb_vals->pool_dess[pool_index];
 	char sbpm_pl[MLXSW_REG_SBPM_LEN];
 
+	if (local_port == MLXSW_PORT_CPU_PORT &&
+	    des->dir == MLXSW_REG_SBXX_DIR_INGRESS)
+		return 0;
+
 	mlxsw_reg_sbpm_pack(sbpm_pl, local_port, des->pool, des->dir,
 			    true, 0, 0);
 	return mlxsw_reg_trans_query(mlxsw_sp->core, MLXSW_REG(sbpm), sbpm_pl,
@@ -273,6 +277,10 @@ static int mlxsw_sp_sb_pm_occ_query(stru
 	char sbpm_pl[MLXSW_REG_SBPM_LEN];
 	struct mlxsw_sp_sb_pm *pm;
 
+	if (local_port == MLXSW_PORT_CPU_PORT &&
+	    des->dir == MLXSW_REG_SBXX_DIR_INGRESS)
+		return 0;
+
 	pm = mlxsw_sp_sb_pm_get(mlxsw_sp, local_port, pool_index);
 	mlxsw_reg_sbpm_pack(sbpm_pl, local_port, des->pool, des->dir,
 			    false, 0, 0);
@@ -1197,6 +1205,11 @@ static void mlxsw_sp_sb_sr_occ_query_cb(
 	     local_port < mlxsw_core_max_ports(mlxsw_core); local_port++) {
 		if (!mlxsw_sp->ports[local_port])
 			continue;
+		if (local_port == MLXSW_PORT_CPU_PORT) {
+			/* Ingress quotas are not supported for the CPU port */
+			masked_count++;
+			continue;
+		}
 		for (i = 0; i < MLXSW_SP_SB_ING_TC_COUNT; i++) {
 			cm = mlxsw_sp_sb_cm_get(mlxsw_sp, local_port, i,
 						MLXSW_REG_SBXX_DIR_INGRESS);
@@ -1232,7 +1245,7 @@ int mlxsw_sp_sb_occ_snapshot(struct mlxs
 	char *sbsr_pl;
 	u8 masked_count;
 	u8 local_port_1;
-	u8 local_port = 0;
+	u8 local_port;
 	int i;
 	int err;
 	int err2;
@@ -1241,8 +1254,8 @@ int mlxsw_sp_sb_occ_snapshot(struct mlxs
 	if (!sbsr_pl)
 		return -ENOMEM;
 
+	local_port = MLXSW_PORT_CPU_PORT;
 next_batch:
-	local_port++;
 	local_port_1 = local_port;
 	masked_count = 0;
 	mlxsw_reg_sbsr_pack(sbsr_pl, false);
@@ -1253,7 +1266,11 @@ next_batch:
 	for (; local_port < mlxsw_core_max_ports(mlxsw_core); local_port++) {
 		if (!mlxsw_sp->ports[local_port])
 			continue;
-		mlxsw_reg_sbsr_ingress_port_mask_set(sbsr_pl, local_port, 1);
+		if (local_port != MLXSW_PORT_CPU_PORT) {
+			/* Ingress quotas are not supported for the CPU port */
+			mlxsw_reg_sbsr_ingress_port_mask_set(sbsr_pl,
+							     local_port, 1);
+		}
 		mlxsw_reg_sbsr_egress_port_mask_set(sbsr_pl, local_port, 1);
 		for (i = 0; i < mlxsw_sp->sb_vals->pool_count; i++) {
 			err = mlxsw_sp_sb_pm_occ_query(mlxsw_sp, local_port, i,
@@ -1274,8 +1291,10 @@ do_query:
 				    cb_priv);
 	if (err)
 		goto out;
-	if (local_port < mlxsw_core_max_ports(mlxsw_core))
+	if (local_port < mlxsw_core_max_ports(mlxsw_core)) {
+		local_port++;
 		goto next_batch;
+	}
 
 out:
 	err2 = mlxsw_reg_trans_bulk_wait(&bulk_list);
@@ -1292,7 +1311,7 @@ int mlxsw_sp_sb_occ_max_clear(struct mlx
 	LIST_HEAD(bulk_list);
 	char *sbsr_pl;
 	unsigned int masked_count;
-	u8 local_port = 0;
+	u8 local_port;
 	int i;
 	int err;
 	int err2;
@@ -1301,8 +1320,8 @@ int mlxsw_sp_sb_occ_max_clear(struct mlx
 	if (!sbsr_pl)
 		return -ENOMEM;
 
+	local_port = MLXSW_PORT_CPU_PORT;
 next_batch:
-	local_port++;
 	masked_count = 0;
 	mlxsw_reg_sbsr_pack(sbsr_pl, true);
 	for (i = 0; i < MLXSW_SP_SB_ING_TC_COUNT; i++)
@@ -1312,7 +1331,11 @@ next_batch:
 	for (; local_port < mlxsw_core_max_ports(mlxsw_core); local_port++) {
 		if (!mlxsw_sp->ports[local_port])
 			continue;
-		mlxsw_reg_sbsr_ingress_port_mask_set(sbsr_pl, local_port, 1);
+		if (local_port != MLXSW_PORT_CPU_PORT) {
+			/* Ingress quotas are not supported for the CPU port */
+			mlxsw_reg_sbsr_ingress_port_mask_set(sbsr_pl,
+							     local_port, 1);
+		}
 		mlxsw_reg_sbsr_egress_port_mask_set(sbsr_pl, local_port, 1);
 		for (i = 0; i < mlxsw_sp->sb_vals->pool_count; i++) {
 			err = mlxsw_sp_sb_pm_occ_clear(mlxsw_sp, local_port, i,
@@ -1329,8 +1352,10 @@ do_query:
 				    &bulk_list, NULL, 0);
 	if (err)
 		goto out;
-	if (local_port < mlxsw_core_max_ports(mlxsw_core))
+	if (local_port < mlxsw_core_max_ports(mlxsw_core)) {
+		local_port++;
 		goto next_batch;
+	}
 
 out:
 	err2 = mlxsw_reg_trans_bulk_wait(&bulk_list);