Re: [PATCH net v2 1/6] net: stmmac: Remove VLAN perfect matching dead code
From: Maxime Chevallier <maxime.chevallier@bootlin.com>
Date: 2026-08-23 07:49:25
Also in:
linux-kselftest, lkml, netdev
Hi Ovidiu, On 8/21/26 19:09, Ovidiu Panait wrote:
stmmac_vlan_update() falls back to "perfect matching" when the VLAN hash
filter is unavailable (!priv->dma_cap.vlhash). This fallback has been
unreachable in normal operation since its introduction in
commit c7ab0b8088d7 ("net: stmmac: Fallback to VLAN Perfect filtering if
HASH is not available") because the NETIF_F_HW_VLAN_{CTAG,STAG}_FILTER
features are advertised only when priv->dma_cap.vlhash is true.
The fallback is also duplicating the code in vlan_add_hw_rx_fltr(), which
is always available since stmmac_get_num_vlan() returns at least 1.
Therefore, remove it.
Fixes: c7ab0b8088d7 ("net: stmmac: Fallback to VLAN Perfect filtering if HASH is not available")
Signed-off-by: Ovidiu Panait <redacted>Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Maxime
quoted hunk ↗ jump to hunk
--- v2 changes: None. drivers/net/ethernet/stmicro/stmmac/hwif.h | 2 +- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 13 +----- .../net/ethernet/stmicro/stmmac/stmmac_vlan.c | 41 +------------------ 3 files changed, 4 insertions(+), 52 deletions(-)diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.h b/drivers/net/ethernet/stmicro/stmmac/hwif.h index 04dafec021b4..6f26dbf95ce1 100644 --- a/drivers/net/ethernet/stmicro/stmmac/hwif.h +++ b/drivers/net/ethernet/stmicro/stmmac/hwif.h@@ -633,7 +633,7 @@ struct stmmac_est_ops { struct stmmac_vlan_ops { /* VLAN */ void (*update_vlan_hash)(struct mac_device_info *hw, u32 hash, - u16 perfect_match, bool is_double); + bool is_double); void (*enable_vlan)(struct mac_device_info *hw, u32 type); void (*rx_hw_vlan)(struct mac_device_info *hw, struct dma_desc *rx_desc, struct sk_buff *skb);diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index b2b7d0242dd3..16fe56a1f617 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c@@ -6809,29 +6809,18 @@ static u32 stmmac_vid_crc32_le(__le16 vid_le) static int stmmac_vlan_update(struct stmmac_priv *priv, bool is_double) { u32 crc, hash = 0; - u16 pmatch = 0; - int count = 0; u16 vid = 0; for_each_set_bit(vid, priv->active_vlans, VLAN_N_VID) { __le16 vid_le = cpu_to_le16(vid); crc = bitrev32(~stmmac_vid_crc32_le(vid_le)) >> 28; hash |= (1 << crc); - count++; - } - - if (!priv->dma_cap.vlhash) { - if (count > 2) /* VID = 0 always passes filter */ - return -EOPNOTSUPP; - - pmatch = vid; - hash = 0; } if (!netif_running(priv->dev)) return 0; - return stmmac_update_vlan_hash(priv, priv->hw, hash, pmatch, is_double); + return stmmac_update_vlan_hash(priv, priv->hw, hash, is_double); } /* FIXME: This may need RXC to be running, but it may be called with BHdiff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c index e24efe3bfedb..983a90cb9767 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c@@ -162,7 +162,7 @@ static void vlan_restore_hw_rx_fltr(struct net_device *dev, } static void vlan_update_hash(struct mac_device_info *hw, u32 hash, - u16 perfect_match, bool is_double) + bool is_double) { void __iomem *ioaddr = hw->pcsr; u32 value;@@ -184,20 +184,6 @@ static void vlan_update_hash(struct mac_device_info *hw, u32 hash, } writel(value, ioaddr + VLAN_TAG); - } else if (perfect_match) { - u32 value = VLAN_ETV; - - if (is_double) { - value |= VLAN_EDVLP; - value |= VLAN_ESVL; - value |= VLAN_DOVLTC; - } else { - value &= ~VLAN_EDVLP; - value &= ~VLAN_ESVL; - value &= ~VLAN_DOVLTC; - } - - writel(value | perfect_match, ioaddr + VLAN_TAG); } else { value &= ~(VLAN_VTHM | VLAN_ETV); value &= ~(VLAN_EDVLP | VLAN_ESVL);@@ -251,7 +237,7 @@ static void vlan_set_hw_mode(struct mac_device_info *hw) } static void dwxgmac2_update_vlan_hash(struct mac_device_info *hw, u32 hash, - u16 perfect_match, bool is_double) + bool is_double) { void __iomem *ioaddr = hw->pcsr;@@ -279,29 +265,6 @@ static void dwxgmac2_update_vlan_hash(struct mac_device_info *hw, u32 hash, value &= ~VLAN_VID; writel(value, ioaddr + VLAN_TAG); - } else if (perfect_match) { - u32 value = readl(ioaddr + XGMAC_PACKET_FILTER); - - value |= XGMAC_FILTER_VTFE; - - writel(value, ioaddr + XGMAC_PACKET_FILTER); - - value = readl(ioaddr + VLAN_TAG); - - value &= ~VLAN_VTHM; - value |= VLAN_ETV; - if (is_double) { - value |= VLAN_EDVLP; - value |= VLAN_ESVL; - value |= VLAN_DOVLTC; - } else { - value &= ~VLAN_EDVLP; - value &= ~VLAN_ESVL; - value &= ~VLAN_DOVLTC; - } - - value &= ~VLAN_VID; - writel(value | perfect_match, ioaddr + VLAN_TAG); } else { u32 value = readl(ioaddr + XGMAC_PACKET_FILTER);