diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index f891ddf19dbc77d9d00fdafb61240e49bf5f4470..533793a15621f3415d46765a6f66ccdfdc1c15f3 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -671,19 +671,28 @@ int mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 	if (err)
 		return err;
 
-	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
+	for (i = 0; i < DCBX_MAX_BUFFERS; i++) {
 		struct mlxsw_sp_hdroom_buf *buf = &hdroom->bufs.buf[i];
 		u16 thres_cells;
 		u16 delay_cells;
 		u16 total_cells;
 
-		if (!mlxsw_sp_hdroom_buf_is_used(hdroom, i))
-			continue;
+		if (!mlxsw_sp_hdroom_buf_is_used(hdroom, i)) {
+			thres_cells = 0;
+			delay_cells = 0;
+		} else if (buf->lossy) {
+			thres_cells = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, hdroom->mtu);
+			delay_cells = 0;
+		} else {
+			thres_cells = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, hdroom->mtu);
+			delay_cells = mlxsw_sp_hdroom_buf_delay_get(mlxsw_sp, hdroom);
+		}
 
-		thres_cells = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, hdroom->mtu);
 		thres_cells = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, thres_cells);
-		delay_cells = mlxsw_sp_hdroom_buf_delay_get(mlxsw_sp, hdroom);
 		delay_cells = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, delay_cells);
+
+		buf->thres_cells = thres_cells;
+		buf->size_cells = thres_cells + delay_cells;
 		total_cells = thres_cells + delay_cells;
 
 		taken_headroom_cells += total_cells;
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index 5245367d6fb23e6a9c864d4cf4d770547ac7b1c6..b3c9cdcc7a062d3705b0bd744821893b259cbc5a 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -447,6 +447,8 @@ struct mlxsw_sp_hdroom_prio {
 };
 
 struct mlxsw_sp_hdroom_buf {
+	u32 thres_cells;
+	u32 size_cells;
 	bool lossy;
 };