[PATCH] net: ethernet: mtk_wed: increase WED v2 WDMA RESV_BUFF to 0x80
From: Shiji Yang <hidden>
Date: 2026-08-19 13:07:53
Also in:
linux-arm-kernel, linux-mediatek, lkml
Subsystem:
mediatek ethernet driver, networking drivers, the rest · Maintainers:
Felix Fietkau, Lorenzo Bianconi, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Change WDMA RESV_BUFF from 0x40 to 0x80 to avoid CDM TX FIFO overflow. Without this patch mt7986 and mt7981 may have WDMA TX hang issue. This patch was pulled from mtk-openwrt-feeds GPL open source project. Link: https://github.com/mediatek/mtk-openwrt-feeds/commit/07c87502e854b68b48544d101b6fe17ec059b97b Signed-off-by: Shiji Yang <redacted> --- drivers/net/ethernet/mediatek/mtk_wed.c | 5 +++++ drivers/net/ethernet/mediatek/mtk_wed_regs.h | 1 + 2 files changed, 6 insertions(+)
diff --git a/drivers/net/ethernet/mediatek/mtk_wed.c b/drivers/net/ethernet/mediatek/mtk_wed.c
index 10d9beaae..53d3b7e00 100644
--- a/drivers/net/ethernet/mediatek/mtk_wed.c
+++ b/drivers/net/ethernet/mediatek/mtk_wed.c@@ -2071,6 +2071,11 @@ mtk_wed_dma_enable(struct mtk_wed_device *dev) wdma_set(dev, MTK_WDMA_GLO_CFG, MTK_WDMA_GLO_CFG_TX_DMA_EN); } + if (mtk_wed_is_v2(dev->hw)) + wdma_m32(dev, MTK_WDMA_GLO_CFG, + MTK_WDMA_GLO_CFG_RESV_BUFF, + FIELD_PREP(MTK_WDMA_GLO_CFG_RESV_BUFF, 0x80)); + wed_set(dev, MTK_WED_GLO_CFG, MTK_WED_GLO_CFG_TX_DMA_EN | MTK_WED_GLO_CFG_RX_DMA_EN);
diff --git a/drivers/net/ethernet/mediatek/mtk_wed_regs.h b/drivers/net/ethernet/mediatek/mtk_wed_regs.h
index c71190924..e5f83100d 100644
--- a/drivers/net/ethernet/mediatek/mtk_wed_regs.h
+++ b/drivers/net/ethernet/mediatek/mtk_wed_regs.h@@ -433,6 +433,7 @@ struct mtk_wdma_desc { #define MTK_WDMA_GLO_CFG_TX_DMA_BUSY BIT(1) #define MTK_WDMA_GLO_CFG_RX_DMA_EN BIT(2) #define MTK_WDMA_GLO_CFG_RX_DMA_BUSY BIT(3) +#define MTK_WDMA_GLO_CFG_RESV_BUFF GENMASK(23, 16) #define MTK_WDMA_GLO_CFG_RX_INFO3_PRERES BIT(26) #define MTK_WDMA_GLO_CFG_RX_INFO2_PRERES BIT(27) #define MTK_WDMA_GLO_CFG_RX_INFO1_PRERES BIT(28)
--
2.53.0