[PATCH net-next 4/4] net: stmmac: Defer VLAN HW configuration when interface is down
From: Ovidiu Panait
Date: Mon Feb 23 2026 - 07:50:15 EST
VLAN register accesses on the MAC side require the PHY RX clock to be
active. When the network interface is down, the PHY is suspended and
the RX clock is unavailable, causing VLAN operations to fail with
timeouts.
The VLAN core automatically removes VID 0 after the interface goes down
and re-adds it when it comes back up, so these timeouts happen during
normal interface down/up:
# ip link set end1 down
renesas-gbeth 15c40000.ethernet end1: Timeout accessing MAC_VLAN_Tag_Filter
renesas-gbeth 15c40000.ethernet end1: failed to kill vid 0081/0
Adding VLANs while the interface is down also fails:
# ip link add link end1 name end1.10 type vlan id 10
renesas-gbeth 15c40000.ethernet end1: Timeout accessing MAC_VLAN_Tag_Filter
RTNETLINK answers: Device or resource busy
Use the write_hw parameter introduced in the previous commit to skip
hardware register writes when the interface is down. The software state
is always kept up to date regardless of interface state.
When the interface is brought up, stmmac_vlan_configure() is called
to write the VLAN state to hardware.
Signed-off-by: Ovidiu Panait <ovidiu.panait.rb@xxxxxxxxxxx>
---
.../net/ethernet/stmicro/stmmac/stmmac_main.c | 33 +++++++++++++++----
.../net/ethernet/stmicro/stmmac/stmmac_vlan.c | 9 ++---
2 files changed, 29 insertions(+), 13 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 536668a0d6dd..d0aede23ae0d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -156,6 +156,7 @@ static void stmmac_tx_timer_arm(struct stmmac_priv *priv, u32 queue);
static void stmmac_flush_tx_descriptors(struct stmmac_priv *priv, int queue);
static void stmmac_set_dma_operation_mode(struct stmmac_priv *priv, u32 txmode,
u32 rxmode, u32 chan);
+static int stmmac_vlan_configure(struct stmmac_priv *priv);
#ifdef CONFIG_DEBUG_FS
static const struct net_device_ops stmmac_netdev_ops;
@@ -4111,6 +4112,14 @@ static int __stmmac_open(struct net_device *dev,
phylink_start(priv->phylink);
+ if (dev->features & NETIF_F_VLAN_FEATURES) {
+ phylink_rx_clk_stop_block(priv->phylink);
+ ret = stmmac_vlan_configure(priv);
+ phylink_rx_clk_stop_unblock(priv->phylink);
+ if (ret)
+ netdev_err(dev, "Failed to configure VLANs\n");
+ }
+
ret = stmmac_request_irq(dev);
if (ret)
goto irq_error;
@@ -6784,6 +6793,7 @@ static int stmmac_vlan_update(struct stmmac_priv *priv, bool is_double,
static int stmmac_vlan_rx_add_vid(struct net_device *ndev, __be16 proto, u16 vid)
{
struct stmmac_priv *priv = netdev_priv(ndev);
+ bool write_hw = netif_running(ndev);
unsigned int num_double_vlans;
bool is_double = false;
int ret;
@@ -6797,7 +6807,7 @@ static int stmmac_vlan_rx_add_vid(struct net_device *ndev, __be16 proto, u16 vid
set_bit(vid, priv->active_vlans);
num_double_vlans = priv->num_double_vlans + is_double;
- ret = stmmac_vlan_update(priv, num_double_vlans, true);
+ ret = stmmac_vlan_update(priv, num_double_vlans, write_hw);
if (ret) {
clear_bit(vid, priv->active_vlans);
goto err_pm_put;
@@ -6805,10 +6815,11 @@ static int stmmac_vlan_rx_add_vid(struct net_device *ndev, __be16 proto, u16 vid
if (priv->hw->num_vlan) {
ret = stmmac_add_hw_vlan_rx_fltr(priv, ndev, priv->hw, proto,
- vid, true);
+ vid, write_hw);
if (ret) {
clear_bit(vid, priv->active_vlans);
- stmmac_vlan_update(priv, priv->num_double_vlans, true);
+ stmmac_vlan_update(priv, priv->num_double_vlans,
+ write_hw);
goto err_pm_put;
}
}
@@ -6827,6 +6838,7 @@ static int stmmac_vlan_rx_add_vid(struct net_device *ndev, __be16 proto, u16 vid
static int stmmac_vlan_rx_kill_vid(struct net_device *ndev, __be16 proto, u16 vid)
{
struct stmmac_priv *priv = netdev_priv(ndev);
+ bool write_hw = netif_running(ndev);
unsigned int num_double_vlans;
bool is_double = false;
int ret;
@@ -6840,7 +6852,7 @@ static int stmmac_vlan_rx_kill_vid(struct net_device *ndev, __be16 proto, u16 vi
clear_bit(vid, priv->active_vlans);
num_double_vlans = priv->num_double_vlans - is_double;
- ret = stmmac_vlan_update(priv, num_double_vlans, true);
+ ret = stmmac_vlan_update(priv, num_double_vlans, write_hw);
if (ret) {
set_bit(vid, priv->active_vlans);
goto del_vlan_error;
@@ -6848,10 +6860,11 @@ static int stmmac_vlan_rx_kill_vid(struct net_device *ndev, __be16 proto, u16 vi
if (priv->hw->num_vlan) {
ret = stmmac_del_hw_vlan_rx_fltr(priv, ndev, priv->hw, proto,
- vid, true);
+ vid, write_hw);
if (ret) {
set_bit(vid, priv->active_vlans);
- stmmac_vlan_update(priv, priv->num_double_vlans, true);
+ stmmac_vlan_update(priv, priv->num_double_vlans,
+ write_hw);
goto del_vlan_error;
}
}
@@ -6864,6 +6877,14 @@ static int stmmac_vlan_rx_kill_vid(struct net_device *ndev, __be16 proto, u16 vi
return ret;
}
+static int stmmac_vlan_configure(struct stmmac_priv *priv)
+{
+ if (priv->hw->num_vlan)
+ stmmac_restore_hw_vlan_rx_fltr(priv, priv->dev, priv->hw);
+
+ return stmmac_vlan_update(priv, priv->num_double_vlans, true);
+}
+
static int stmmac_bpf(struct net_device *dev, struct netdev_bpf *bpf)
{
struct stmmac_priv *priv = netdev_priv(dev);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c
index b74c173da1b5..070c11870c02 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c
@@ -150,7 +150,6 @@ static void vlan_restore_hw_rx_fltr(struct net_device *dev,
void __iomem *ioaddr = hw->pcsr;
u32 value;
u32 hash;
- u32 val;
int i;
/* Single Rx VLAN Filter */
@@ -160,12 +159,8 @@ static void vlan_restore_hw_rx_fltr(struct net_device *dev,
}
/* Extended Rx VLAN Filter Enable */
- for (i = 0; i < hw->num_vlan; i++) {
- if (hw->vlan_filter[i] & VLAN_TAG_DATA_VEN) {
- val = hw->vlan_filter[i];
- vlan_write_filter(dev, hw, i, val);
- }
- }
+ for (i = 0; i < hw->num_vlan; i++)
+ vlan_write_filter(dev, hw, i, hw->vlan_filter[i]);
hash = readl(ioaddr + VLAN_HASH_TABLE);
if (hash & VLAN_VLHT) {
--
2.34.1