[v6,08/12] net: ethernet: mtk_eth_soc: fix RX data corruption issue
Commit Message
Also set bit 12 when setting up MAC MCR, as MediaTek SDK did the same
change stating:
"If without this patch, kernel might receive invalid packets that are
corrupted by GMAC."[1]
This fixes issues with <= 1G speed where we could previously observe
about 30% packet loss while the bad packet counter was increasing.
Unfortunately the meaning of bit 12 is not documented anywhere in SDK
code or datasheets.
[1]: https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/d8a2975939a12686c4a95c40db21efdc3f821f63
Tested-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 2 +-
drivers/net/ethernet/mediatek/mtk_eth_soc.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
@@ -615,7 +615,7 @@ static int mtk_mac_finish(struct phylink_config *config, unsigned int mode,
/* Setup gmac */
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 |
+ mcr_new |= MAC_MCR_IPG_CFG | MAC_MCR_BIT_12 | MAC_MCR_FORCE_MODE |
MAC_MCR_BACKOFF_EN | MAC_MCR_BACKPR_EN | MAC_MCR_FORCE_LINK;
/* Only update control register when needed! */
@@ -404,6 +404,7 @@
#define MAC_MCR_FORCE_MODE BIT(15)
#define MAC_MCR_TX_EN BIT(14)
#define MAC_MCR_RX_EN BIT(13)
+#define MAC_MCR_BIT_12 BIT(12)
#define MAC_MCR_BACKOFF_EN BIT(9)
#define MAC_MCR_BACKPR_EN BIT(8)
#define MAC_MCR_FORCE_RX_FC BIT(5)