From 9fcf274d93af17396f20cccb63f1d4c17492a000 Mon Sep 17 00:00:00 2001 From: Nazim Amirul Date: Mon, 13 Jul 2026 19:37:14 -0700 Subject: [PATCH] net: stmmac: xgmac: fix l4 filter port overwrite on register update The XGMAC_L4_ADDR register holds both source and destination port match values. The current implementation overwrites the entire register when configuring either port, so setting one silently erases the other. Fix this by reading the register first, then masking and updating only the relevant field before writing back. Fixes: 425eabddaf0f ("net: stmmac: Implement L3/L4 Filters using TC Flower") Signed-off-by: Rohan G Thomas Signed-off-by: Nazim Amirul Reviewed-by: Maxime Chevallier Link: https://patch.msgid.link/20260714023716.29865-3-muhammad.nazim.amirul.nazle.asmade@altera.com Reviewed-by: Jakub Raczynski Signed-off-by: Paolo Abeni --- .../ethernet/stmicro/stmmac/dwxgmac2_core.c | 28 +++++++++++-------- 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c index f02b434bbd50..52054f31376d 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c @@ -1370,36 +1370,40 @@ static int dwxgmac2_config_l4_filter(struct mac_device_info *hw, u32 filter_no, value &= ~XGMAC_L4PEN0; } - value &= ~(XGMAC_L4SPM0 | XGMAC_L4SPIM0); - value &= ~(XGMAC_L4DPM0 | XGMAC_L4DPIM0); if (sa) { value |= XGMAC_L4SPM0; if (inv) value |= XGMAC_L4SPIM0; + else + value &= ~XGMAC_L4SPIM0; } else { value |= XGMAC_L4DPM0; if (inv) value |= XGMAC_L4DPIM0; + else + value &= ~XGMAC_L4DPIM0; } ret = dwxgmac2_filter_write(hw, filter_no, XGMAC_L3L4_CTRL, value); if (ret) return ret; + ret = dwxgmac2_filter_read(hw, filter_no, XGMAC_L4_ADDR, &value); + if (ret) + return ret; + if (sa) { - value = FIELD_PREP(XGMAC_L4SP0, match); - - ret = dwxgmac2_filter_write(hw, filter_no, XGMAC_L4_ADDR, value); - if (ret) - return ret; + value &= ~XGMAC_L4SP0; + value |= FIELD_PREP(XGMAC_L4SP0, match); } else { - value = FIELD_PREP(XGMAC_L4DP0, match); - - ret = dwxgmac2_filter_write(hw, filter_no, XGMAC_L4_ADDR, value); - if (ret) - return ret; + value &= ~XGMAC_L4DP0; + value |= FIELD_PREP(XGMAC_L4DP0, match); } + ret = dwxgmac2_filter_write(hw, filter_no, XGMAC_L4_ADDR, value); + if (ret) + return ret; + if (!en) return dwxgmac2_filter_write(hw, filter_no, XGMAC_L3L4_CTRL, 0);