net: hns: adds limitation for debug port mtu

If mtu for debug port is set more than 1500, it may cause that packets
are dropped by ppe. So maximum value for debug port should be 1500.

Signed-off-by: Kejian Yan <yankejian@huawei.com>
Signed-off-by: Yisen Zhuang <Yisen.Zhuang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 4 insertions, 0 deletions

diff --git a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c
index 50237fbe3090..a38084a22bf2 100644
--- a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.c
@@ -470,6 +470,9 @@ int hns_mac_set_mtu(struct hns_mac_cb *mac_cb, u32 new_mtu)
         u32 max_frm = AE_IS_VER1(mac_cb->dsaf_dev->dsaf_ver) ?
                         MAC_MAX_MTU : MAC_MAX_MTU_V2;
 
+        if (mac_cb->mac_type == HNAE_PORT_DEBUG)
+                max_frm = MAC_MAX_MTU_DBG;
+
         if ((new_mtu < MAC_MIN_MTU) || (new_frm > max_frm) ||
             (new_frm > HNS_RCB_RING_MAX_BD_PER_PKT * buf_size))
                 return -EINVAL;
diff --git a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.h b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.h
index 7b47701daeca..823b6e78c8aa 100644
--- a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.h
+++ b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_mac.h
@@ -28,6 +28,7 @@ struct dsaf_device;
 #define MAC_MAX_MTU             9600
 #define MAC_MAX_MTU_V2          9728
 #define MAC_MIN_MTU             68
+#define MAC_MAX_MTU_DBG         MAC_DEFAULT_MTU
 
 #define MAC_DEFAULT_PAUSE_TIME 0xff