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kernel: backport MT7530 VLAN fix

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Fix FDB learning bugs when VLAN filtering is enabled.

Signed-off-by: DENG Qingfang <dqfext@gmail.com>
Tested-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Tested-by: Stijn Tintel <stijn@linux-ipv6.be>
This commit is contained in:
DENG Qingfang 2022-02-03 20:07:02 +08:00 committed by Stijn Tintel
parent 4834565bb4
commit ee6ba216d8
5 changed files with 523 additions and 0 deletions
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65
target/linux/generic/backport-5.10/765-v5.15-net-dsa-mt7530-disable-learning-on-standalone-ports.patch Normal file
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From ba2203f36b981235556504fb7b62baee28512a40 Mon Sep 17 00:00:00 2001
From: DENG Qingfang <dqfext@gmail.com>
Date: Tue, 24 Aug 2021 11:37:50 +0800
Subject: [PATCH] net: dsa: mt7530: disable learning on standalone ports
This is a partial backport of commit 5a30833b9a16f8d1aa15de06636f9317ca51f9df
("net: dsa: mt7530: support MDB and bridge flag operations") upstream.
Make sure that the standalone ports start up with learning disabled.
Signed-off-by: DENG Qingfang <dqfext@gmail.com>
---
drivers/net/dsa/mt7530.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -1163,6 +1163,8 @@ mt7530_port_bridge_join(struct dsa_switc
PCR_MATRIX_MASK, PCR_MATRIX(port_bitmap));
priv->ports[port].pm |= PCR_MATRIX(port_bitmap);
+ mt7530_clear(priv, MT7530_PSC_P(port), SA_DIS);
+
mutex_unlock(&priv->reg_mutex);
return 0;
@@ -1260,6 +1262,8 @@ mt7530_port_bridge_leave(struct dsa_swit
PCR_MATRIX(BIT(MT7530_CPU_PORT)));
priv->ports[port].pm = PCR_MATRIX(BIT(MT7530_CPU_PORT));
+ mt7530_set(priv, MT7530_PSC_P(port), SA_DIS);
+
mutex_unlock(&priv->reg_mutex);
}
@@ -1817,9 +1821,13 @@ mt7530_setup(struct dsa_switch *ds)
ret = mt753x_cpu_port_enable(ds, i);
if (ret)
return ret;
- } else
+ } else {
mt7530_port_disable(ds, i);
+ /* Disable learning by default on all user ports */
+ mt7530_set(priv, MT7530_PSC_P(i), SA_DIS);
+ }
+
/* Enable consistent egress tag */
mt7530_rmw(priv, MT7530_PVC_P(i), PVC_EG_TAG_MASK,
PVC_EG_TAG(MT7530_VLAN_EG_CONSISTENT));
@@ -1979,9 +1987,13 @@ mt7531_setup(struct dsa_switch *ds)
ret = mt753x_cpu_port_enable(ds, i);
if (ret)
return ret;
- } else
+ } else {
mt7530_port_disable(ds, i);
+ /* Disable learning by default on all user ports */
+ mt7530_set(priv, MT7530_PSC_P(i), SA_DIS);
+ }
+
/* Enable consistent egress tag */
mt7530_rmw(priv, MT7530_PVC_P(i), PVC_EG_TAG_MASK,
PVC_EG_TAG(MT7530_VLAN_EG_CONSISTENT));

102
target/linux/generic/backport-5.10/766-v5.15-net-dsa-mt7530-enable-assisted-learning-on-CPU-port.patch Normal file
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From 59c8adbc8e2c7f6b46385f36962eadaad3ea2daa Mon Sep 17 00:00:00 2001
From: DENG Qingfang <dqfext@gmail.com>
Date: Wed, 4 Aug 2021 00:04:01 +0800
Subject: [PATCH] net: dsa: mt7530: enable assisted learning on CPU port
Consider the following bridge configuration, where bond0 is not
offloaded:
+-- br0 --+
/ / | \
/ / | \
/ | | bond0
/ | | / \
swp0 swp1 swp2 swp3 swp4
. . .
. . .
A B C
Address learning is enabled on offloaded ports (swp0~2) and the CPU
port, so when client A sends a packet to C, the following will happen:
1. The switch learns that client A can be reached at swp0.
2. The switch probably already knows that client C can be reached at the
CPU port, so it forwards the packet to the CPU.
3. The bridge core knows client C can be reached at bond0, so it
forwards the packet back to the switch.
4. The switch learns that client A can be reached at the CPU port.
5. The switch forwards the packet to either swp3 or swp4, according to
the packet's tag.
That makes client A's MAC address flap between swp0 and the CPU port. If
client B sends a packet to A, it is possible that the packet is
forwarded to the CPU. With offload_fwd_mark = 1, the bridge core won't
forward it back to the switch, resulting in packet loss.
As we have the assisted_learning_on_cpu_port in DSA core now, enable
that and disable hardware learning on the CPU port.
Signed-off-by: DENG Qingfang <dqfext@gmail.com>
Reviewed-by: Vladimir Oltean <oltean@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/dsa/mt7530.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -1747,6 +1747,7 @@ mt7530_setup(struct dsa_switch *ds)
*/
dn = dsa_to_port(ds, MT7530_CPU_PORT)->master->dev.of_node->parent;
ds->configure_vlan_while_not_filtering = true;
+ ds->assisted_learning_on_cpu_port = true;
ds->mtu_enforcement_ingress = true;
if (priv->id == ID_MT7530) {
@@ -1817,15 +1818,15 @@ mt7530_setup(struct dsa_switch *ds)
mt7530_rmw(priv, MT7530_PCR_P(i), PCR_MATRIX_MASK,
PCR_MATRIX_CLR);
+ /* Disable learning by default on all ports */
+ mt7530_set(priv, MT7530_PSC_P(i), SA_DIS);
+
if (dsa_is_cpu_port(ds, i)) {
ret = mt753x_cpu_port_enable(ds, i);
if (ret)
return ret;
} else {
mt7530_port_disable(ds, i);
-
- /* Disable learning by default on all user ports */
- mt7530_set(priv, MT7530_PSC_P(i), SA_DIS);
}
/* Enable consistent egress tag */
@@ -1981,6 +1982,9 @@ mt7531_setup(struct dsa_switch *ds)
mt7530_rmw(priv, MT7530_PCR_P(i), PCR_MATRIX_MASK,
PCR_MATRIX_CLR);
+ /* Disable learning by default on all ports */
+ mt7530_set(priv, MT7530_PSC_P(i), SA_DIS);
+
mt7530_set(priv, MT7531_DBG_CNT(i), MT7531_DIS_CLR);
if (dsa_is_cpu_port(ds, i)) {
@@ -1989,9 +1993,6 @@ mt7531_setup(struct dsa_switch *ds)
return ret;
} else {
mt7530_port_disable(ds, i);
-
- /* Disable learning by default on all user ports */
- mt7530_set(priv, MT7530_PSC_P(i), SA_DIS);
}
/* Enable consistent egress tag */
@@ -2000,6 +2001,7 @@ mt7531_setup(struct dsa_switch *ds)
}
ds->configure_vlan_while_not_filtering = true;
+ ds->assisted_learning_on_cpu_port = true;
ds->mtu_enforcement_ingress = true;
/* Flush the FDB table */

262
target/linux/generic/backport-5.10/767-v5.15-net-dsa-mt7530-use-independent-VLAN-learning-on-VLAN.patch Normal file
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From e3a402764c5753698e7a9e45d4d21f093faa7852 Mon Sep 17 00:00:00 2001
From: DENG Qingfang <dqfext@gmail.com>
Date: Wed, 4 Aug 2021 00:04:02 +0800
Subject: [PATCH] net: dsa: mt7530: use independent VLAN learning on
VLAN-unaware bridges
Consider the following bridge configuration, where bond0 is not
offloaded:
+-- br0 --+
/ / | \
/ / | \
/ | | bond0
/ | | / \
swp0 swp1 swp2 swp3 swp4
. . .
. . .
A B C
Ideally, when the switch receives a packet from swp3 or swp4, it should
forward the packet to the CPU, according to the port matrix and unknown
unicast flood settings.
But packet loss will happen if the destination address is at one of the
offloaded ports (swp0~2). For example, when client C sends a packet to
A, the FDB lookup will indicate that it should be forwarded to swp0, but
the port matrix of swp3 and swp4 is configured to only allow the CPU to
be its destination, so it is dropped.
However, this issue does not happen if the bridge is VLAN-aware. That is
because VLAN-aware bridges use independent VLAN learning, i.e. use VID
for FDB lookup, on offloaded ports. As swp3 and swp4 are not offloaded,
shared VLAN learning with default filter ID of 0 is used instead. So the
lookup for A with filter ID 0 never hits and the packet can be forwarded
to the CPU.
In the current code, only two combinations were used to toggle user
ports' VLAN awareness: one is PCR.PORT_VLAN set to port matrix mode with
PVC.VLAN_ATTR set to transparent port, the other is PCR.PORT_VLAN set to
security mode with PVC.VLAN_ATTR set to user port.
It turns out that only PVC.VLAN_ATTR contributes to VLAN awareness, and
port matrix mode just skips the VLAN table lookup. The reference manual
is somehow misleading when describing PORT_VLAN modes. It states that
PORT_MEM (VLAN port member) is used for destination if the VLAN table
lookup hits, but actually **PORT_MEM & PORT_MATRIX** (bitwise AND of
VLAN port member and port matrix) is used instead, which means we can
have two or more separate VLAN-aware bridges with the same PVID and
traffic won't leak between them.
Therefore, to solve this, enable independent VLAN learning with PVID 0
on VLAN-unaware bridges, by setting their PCR.PORT_VLAN to fallback
mode, while leaving standalone ports in port matrix mode. The CPU port
is always set to fallback mode to serve those bridges.
During testing, it is found that FDB lookup with filter ID of 0 will
also hit entries with VID 0 even with independent VLAN learning. To
avoid that, install all VLANs with filter ID of 1.
Signed-off-by: DENG Qingfang <dqfext@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/dsa/mt7530.c | 72 +++++++++++++++++++++++++++++-----------
drivers/net/dsa/mt7530.h | 9 ++++-
2 files changed, 60 insertions(+), 21 deletions(-)
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -1011,6 +1011,10 @@ mt753x_cpu_port_enable(struct dsa_switch
mt7530_write(priv, MT7530_PCR_P(port),
PCR_MATRIX(dsa_user_ports(priv->ds)));
+ /* Set to fallback mode for independent VLAN learning */
+ mt7530_rmw(priv, MT7530_PCR_P(port), PCR_PORT_VLAN_MASK,
+ MT7530_PORT_FALLBACK_MODE);
+
return 0;
}
@@ -1165,6 +1169,10 @@ mt7530_port_bridge_join(struct dsa_switc
mt7530_clear(priv, MT7530_PSC_P(port), SA_DIS);
+ /* Set to fallback mode for independent VLAN learning */
+ mt7530_rmw(priv, MT7530_PCR_P(port), PCR_PORT_VLAN_MASK,
+ MT7530_PORT_FALLBACK_MODE);
+
mutex_unlock(&priv->reg_mutex);
return 0;
@@ -1177,16 +1185,21 @@ mt7530_port_set_vlan_unaware(struct dsa_
bool all_user_ports_removed = true;
int i;
- /* When a port is removed from the bridge, the port would be set up
- * back to the default as is at initial boot which is a VLAN-unaware
- * port.
+ /* This is called after .port_bridge_leave when leaving a VLAN-aware
+ * bridge. Don't set standalone ports to fallback mode.
*/
- mt7530_rmw(priv, MT7530_PCR_P(port), PCR_PORT_VLAN_MASK,
- MT7530_PORT_MATRIX_MODE);
+ if (dsa_to_port(ds, port)->bridge_dev)
+ mt7530_rmw(priv, MT7530_PCR_P(port), PCR_PORT_VLAN_MASK,
+ MT7530_PORT_FALLBACK_MODE);
+
mt7530_rmw(priv, MT7530_PVC_P(port), VLAN_ATTR_MASK | PVC_EG_TAG_MASK,
VLAN_ATTR(MT7530_VLAN_TRANSPARENT) |
PVC_EG_TAG(MT7530_VLAN_EG_CONSISTENT));
+ /* Set PVID to 0 */
+ mt7530_rmw(priv, MT7530_PPBV1_P(port), G0_PORT_VID_MASK,
+ G0_PORT_VID_DEF);
+
for (i = 0; i < MT7530_NUM_PORTS; i++) {
if (dsa_is_user_port(ds, i) &&
dsa_port_is_vlan_filtering(dsa_to_port(ds, i))) {
@@ -1212,15 +1225,14 @@ mt7530_port_set_vlan_aware(struct dsa_sw
struct mt7530_priv *priv = ds->priv;
/* Trapped into security mode allows packet forwarding through VLAN
- * table lookup. CPU port is set to fallback mode to let untagged
- * frames pass through.
+ * table lookup.
*/
- if (dsa_is_cpu_port(ds, port))
- mt7530_rmw(priv, MT7530_PCR_P(port), PCR_PORT_VLAN_MASK,
- MT7530_PORT_FALLBACK_MODE);
- else
+ if (dsa_is_user_port(ds, port)) {
mt7530_rmw(priv, MT7530_PCR_P(port), PCR_PORT_VLAN_MASK,
MT7530_PORT_SECURITY_MODE);
+ mt7530_rmw(priv, MT7530_PPBV1_P(port), G0_PORT_VID_MASK,
+ G0_PORT_VID(priv->ports[port].pvid));
+ }
/* Set the port as a user port which is to be able to recognize VID
* from incoming packets before fetching entry within the VLAN table.
@@ -1264,6 +1276,13 @@ mt7530_port_bridge_leave(struct dsa_swit
mt7530_set(priv, MT7530_PSC_P(port), SA_DIS);
+ /* When a port is removed from the bridge, the port would be set up
+ * back to the default as is at initial boot which is a VLAN-unaware
+ * port.
+ */
+ mt7530_rmw(priv, MT7530_PCR_P(port), PCR_PORT_VLAN_MASK,
+ MT7530_PORT_MATRIX_MODE);
+
mutex_unlock(&priv->reg_mutex);
}
@@ -1406,7 +1425,8 @@ mt7530_hw_vlan_add(struct mt7530_priv *p
/* Validate the entry with independent learning, create egress tag per
* VLAN and joining the port as one of the port members.
*/
- val = IVL_MAC | VTAG_EN | PORT_MEM(new_members) | VLAN_VALID;
+ val = IVL_MAC | VTAG_EN | PORT_MEM(new_members) | FID(FID_BRIDGED) |
+ VLAN_VALID;
mt7530_write(priv, MT7530_VAWD1, val);
/* Decide whether adding tag or not for those outgoing packets from the
@@ -1499,9 +1519,13 @@ mt7530_port_vlan_add(struct dsa_switch *
}
if (pvid) {
- mt7530_rmw(priv, MT7530_PPBV1_P(port), G0_PORT_VID_MASK,
- G0_PORT_VID(vlan->vid_end));
priv->ports[port].pvid = vlan->vid_end;
+
+ /* Only configure PVID if VLAN filtering is enabled */
+ if (dsa_port_is_vlan_filtering(dsa_to_port(ds, port)))
+ mt7530_rmw(priv, MT7530_PPBV1_P(port),
+ G0_PORT_VID_MASK,
+ G0_PORT_VID(vlan->vid_end));
}
mutex_unlock(&priv->reg_mutex);
@@ -1513,11 +1537,10 @@ mt7530_port_vlan_del(struct dsa_switch *
{
struct mt7530_hw_vlan_entry target_entry;
struct mt7530_priv *priv = ds->priv;
- u16 vid, pvid;
+ u16 vid;
mutex_lock(&priv->reg_mutex);
- pvid = priv->ports[port].pvid;
for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
mt7530_hw_vlan_entry_init(&target_entry, port, 0);
mt7530_hw_vlan_update(priv, vid, &target_entry,
@@ -1526,12 +1549,13 @@ mt7530_port_vlan_del(struct dsa_switch *
/* PVID is being restored to the default whenever the PVID port
* is being removed from the VLAN.
*/
- if (pvid == vid)
- pvid = G0_PORT_VID_DEF;
+ if (priv->ports[port].pvid == vid) {
+ priv->ports[port].pvid = G0_PORT_VID_DEF;
+ mt7530_rmw(priv, MT7530_PPBV1_P(port), G0_PORT_VID_MASK,
+ G0_PORT_VID_DEF);
+ }
}
- mt7530_rmw(priv, MT7530_PPBV1_P(port), G0_PORT_VID_MASK, pvid);
- priv->ports[port].pvid = pvid;
mutex_unlock(&priv->reg_mutex);
@@ -1827,6 +1851,10 @@ mt7530_setup(struct dsa_switch *ds)
return ret;
} else {
mt7530_port_disable(ds, i);
+
+ /* Set default PVID to 0 on all user ports */
+ mt7530_rmw(priv, MT7530_PPBV1_P(i), G0_PORT_VID_MASK,
+ G0_PORT_VID_DEF);
}
/* Enable consistent egress tag */
@@ -1993,6 +2021,10 @@ mt7531_setup(struct dsa_switch *ds)
return ret;
} else {
mt7530_port_disable(ds, i);
+
+ /* Set default PVID to 0 on all user ports */
+ mt7530_rmw(priv, MT7530_PPBV1_P(i), G0_PORT_VID_MASK,
+ G0_PORT_VID_DEF);
}
/* Enable consistent egress tag */
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -145,11 +145,18 @@ enum mt7530_vlan_cmd {
#define VTAG_EN BIT(28)
/* VLAN Member Control */
#define PORT_MEM(x) (((x) & 0xff) << 16)
+/* Filter ID */
+#define FID(x) (((x) & 0x7) << 1)
/* VLAN Entry Valid */
#define VLAN_VALID BIT(0)
#define PORT_MEM_SHFT 16
#define PORT_MEM_MASK 0xff
+enum mt7530_fid {
+ FID_STANDALONE = 0,
+ FID_BRIDGED = 1,
+};
+
#define MT7530_VAWD2 0x98
/* Egress Tag Control */
#define ETAG_CTRL_P(p, x) (((x) & 0x3) << ((p) << 1))
@@ -244,7 +251,7 @@ enum mt7530_vlan_port_attr {
#define MT7530_PPBV1_P(x) (0x2014 + ((x) * 0x100))
#define G0_PORT_VID(x) (((x) & 0xfff) << 0)
#define G0_PORT_VID_MASK G0_PORT_VID(0xfff)
-#define G0_PORT_VID_DEF G0_PORT_VID(1)
+#define G0_PORT_VID_DEF G0_PORT_VID(0)
/* Register for port MAC control register */
#define MT7530_PMCR_P(x) (0x3000 + ((x) * 0x100))

40
target/linux/generic/backport-5.10/768-v5.15-net-dsa-mt7530-set-STP-state-on-filter-ID-1.patch Normal file
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@ -0,0 +1,40 @@
From c5ffcefcb40420528d04c63e7dfc88f2845c9831 Mon Sep 17 00:00:00 2001
From: DENG Qingfang <dqfext@gmail.com>
Date: Wed, 4 Aug 2021 00:04:03 +0800
Subject: [PATCH] net: dsa: mt7530: set STP state on filter ID 1
As filter ID 1 is the only one used for bridges, set STP state on it.
Signed-off-by: DENG Qingfang <dqfext@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/dsa/mt7530.c | 3 ++-
drivers/net/dsa/mt7530.h | 4 ++--
2 files changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -1131,7 +1131,8 @@ mt7530_stp_state_set(struct dsa_switch *
break;
}
- mt7530_rmw(priv, MT7530_SSP_P(port), FID_PST_MASK, stp_state);
+ mt7530_rmw(priv, MT7530_SSP_P(port), FID_PST_MASK(FID_BRIDGED),
+ FID_PST(FID_BRIDGED, stp_state));
}
static int
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -183,8 +183,8 @@ enum mt7530_vlan_egress_attr {
/* Register for port STP state control */
#define MT7530_SSP_P(x) (0x2000 + ((x) * 0x100))
-#define FID_PST(x) ((x) & 0x3)
-#define FID_PST_MASK FID_PST(0x3)
+#define FID_PST(fid, state) (((state) & 0x3) << ((fid) * 2))
+#define FID_PST_MASK(fid) FID_PST(fid, 0x3)
enum mt7530_stp_state {
MT7530_STP_DISABLED = 0,

54
target/linux/generic/backport-5.10/769-v5.15-net-dsa-mt7530-always-install-FDB-entries-with-IVL-a.patch Normal file
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@ -0,0 +1,54 @@
From 138c126a33f7564edb66b1da5b847e4a60740bfc Mon Sep 17 00:00:00 2001
From: DENG Qingfang <dqfext@gmail.com>
Date: Wed, 4 Aug 2021 00:04:04 +0800
Subject: [PATCH] net: dsa: mt7530: always install FDB entries with IVL and FID
1
This reverts commit 7e777021780e ("mt7530 mt7530_fdb_write only set ivl
bit vid larger than 1").
Before this series, the default value of all ports' PVID is 1, which is
copied into the FDB entry, even if the ports are VLAN unaware. So
`bridge fdb show` will show entries like `dev swp0 vlan 1 self` even on
a VLAN-unaware bridge.
The blamed commit does not solve that issue completely, instead it may
cause a new issue that FDB is inaccessible in a VLAN-aware bridge with
PVID 1.
This series sets PVID to 0 on VLAN-unaware ports, so `bridge fdb show`
will no longer print `vlan 1` on VLAN-unaware bridges, and that special
case in fdb_write is not required anymore.
Set FDB entries' filter ID to 1 to match the VLAN table.
Signed-off-by: DENG Qingfang <dqfext@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/dsa/mt7530.c | 2 ++
drivers/net/dsa/mt7530.h | 2 ++
2 files changed, 4 insertions(+)
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -361,6 +361,8 @@ mt7530_fdb_write(struct mt7530_priv *pri
int i;
reg[1] |= vid & CVID_MASK;
+ reg[1] |= ATA2_IVL;
+ reg[1] |= ATA2_FID(FID_BRIDGED);
reg[2] |= (aging & AGE_TIMER_MASK) << AGE_TIMER;
reg[2] |= (port_mask & PORT_MAP_MASK) << PORT_MAP;
/* STATIC_ENT indicate that entry is static wouldn't
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -77,6 +77,8 @@ enum mt753x_bpdu_port_fw {
#define STATIC_EMP 0
#define STATIC_ENT 3
#define MT7530_ATA2 0x78
+#define ATA2_IVL BIT(15)
+#define ATA2_FID(x) (((x) & 0x7) << 12)
/* Register for address table write data */
#define MT7530_ATWD 0x7c