net: dsa: mt7530: fix handling of LLDP frames

[ Upstream commit 8332cf6fd7c7087dbc2067115b33979c9851bbc4 ]

LLDP frames are link-local frames, therefore they must be trapped to the
CPU port. Currently, the MT753X switches treat LLDP frames as regular
multicast frames, therefore flooding them to user ports. To fix this, set
LLDP frames to be trapped to the CPU port(s).

Fixes: b8f126a8d543 ("net-next: dsa: add dsa support for Mediatek MT7530 switch")
Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 40be635d2ecc96b4ad37f60bb842c1c1a83fa3d9..e542f5dbe58318a14dcdebb7cd32c4c0f182bdbb 100644 (file)
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -997,6 +997,10 @@ mt753x_trap_frames(struct mt7530_priv *priv)
        /* Trap BPDUs to the CPU port(s) */
        mt7530_rmw(priv, MT753X_BPC, MT753X_BPDU_PORT_FW_MASK,
                   MT753X_BPDU_CPU_ONLY);
+
+       /* Trap LLDP frames with :0E MAC DA to the CPU port(s) */
+       mt7530_rmw(priv, MT753X_RGAC2, MT753X_R0E_PORT_FW_MASK,
+                  MT753X_R0E_PORT_FW(MT753X_BPDU_CPU_ONLY));
 }
 
 static int

diff --git a/drivers/net/dsa/mt7530.h b/drivers/net/dsa/mt7530.h
index 6b2fc6290ea846f54eca8ebc80f8c0663b32502b..31c0f7156b69994f2940d68fcfc9618f5b457e96 100644 (file)
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -65,6 +65,11 @@ enum mt753x_id {
 #define MT753X_BPC                     0x24
 #define  MT753X_BPDU_PORT_FW_MASK      GENMASK(2, 0)
 
+/* Register for :03 and :0E MAC DA frame control */
+#define MT753X_RGAC2                   0x2c
+#define  MT753X_R0E_PORT_FW_MASK       GENMASK(18, 16)
+#define  MT753X_R0E_PORT_FW(x)         FIELD_PREP(MT753X_R0E_PORT_FW_MASK, x)
+
 enum mt753x_bpdu_port_fw {
        MT753X_BPDU_FOLLOW_MFC,
        MT753X_BPDU_CPU_EXCLUDE = 4,