[PATCH 5.15 069/145] net: ethernet: mtk_eth_soc: fix RX data corruption issue

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Daniel Golle <daniel@xxxxxxxxxxxxxx>

[ Upstream commit 193250ace270fecd586dd2d0dfbd9cbd2ade977f ]

Fix data corruption issue with SerDes connected PHYs operating at 1.25
Gbps speed where we could previously observe about 30% packet loss while
the bad packet counter was increasing.

As almost all boards with MediaTek MT7622 or MT7986 use either the MT7531
switch IC operating at 3.125Gbps SerDes rate or single-port PHYs using
rate-adaptation to 2500Base-X mode, this issue only got exposed now when
we started trying to use SFP modules operating with 1.25 Gbps with the
BananaPi R3 board.

The fix is to set bit 12 which disables the RX FIFO clear function when
setting up MAC MCR, MediaTek SDK did the same change stating:
"If without this patch, kernel might receive invalid packets that are
corrupted by GMAC."[1]

[1]: https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/d8a2975939a12686c4a95c40db21efdc3f821f63

Fixes: 42c03844e93d ("net-next: mediatek: add support for MediaTek MT7622 SoC")
Tested-by: Bjørn Mork <bjorn@xxxxxxx>
Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
Reviewed-by: Vladimir Oltean <olteanv@xxxxxxxxx>
Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Link: https://lore.kernel.org/r/138da2735f92c8b6f8578ec2e5a794ee515b665f.1677937317.git.daniel@xxxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 3 ++-
 drivers/net/ethernet/mediatek/mtk_eth_soc.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index cc6a5b2f24e3e..bb1acdb0c62b3 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -363,7 +363,8 @@ static void mtk_mac_config(struct phylink_config *config, unsigned int mode,
 	mcr_cur = mtk_r32(mac->hw, MTK_MAC_MCR(mac->id));
 	mcr_new = mcr_cur;
 	mcr_new |= MAC_MCR_IPG_CFG | MAC_MCR_FORCE_MODE |
-		   MAC_MCR_BACKOFF_EN | MAC_MCR_BACKPR_EN | MAC_MCR_FORCE_LINK;
+		   MAC_MCR_BACKOFF_EN | MAC_MCR_BACKPR_EN | MAC_MCR_FORCE_LINK |
+		   MAC_MCR_RX_FIFO_CLR_DIS;
 
 	/* Only update control register when needed! */
 	if (mcr_new != mcr_cur)
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index f2d90639d7ed1..d60260e00a3fc 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -369,6 +369,7 @@
 #define MAC_MCR_FORCE_MODE	BIT(15)
 #define MAC_MCR_TX_EN		BIT(14)
 #define MAC_MCR_RX_EN		BIT(13)
+#define MAC_MCR_RX_FIFO_CLR_DIS	BIT(12)
 #define MAC_MCR_BACKOFF_EN	BIT(9)
 #define MAC_MCR_BACKPR_EN	BIT(8)
 #define MAC_MCR_FORCE_RX_FC	BIT(5)
-- 
2.39.2






[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux