[PATCH 5.15 294/317] net: mediatek: mtk_eth_soc: clear MAC_MCR_FORCE_LINK only when MAC is up

From: Sasha Levin
Date: Mon Mar 25 2024 - 06:06:19 EST


From: Daniel Golle <daniel@xxxxxxxxxxxxxx>

[ Upstream commit f1b85ef15a99f06ed48871ce933d591127d2dcc0 ]

Clearing bit MAC_MCR_FORCE_LINK which forces the link down too early
can result in MAC ending up in a broken/blocked state.

Fix this by handling this bit in the .mac_link_up and .mac_link_down
calls instead of in .mac_finish.

Fixes: b8fc9f30821e ("net: ethernet: mediatek: Add basic PHYLINK support")
Suggested-by: Mason-cw Chang <Mason-cw.Chang@xxxxxxxxxxxx>
Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index c9d9a082c9f83..711acc6059a4f 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -382,8 +382,7 @@ static int mtk_mac_finish(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_RX_FIFO_CLR_DIS;
+ MAC_MCR_BACKOFF_EN | MAC_MCR_BACKPR_EN | MAC_MCR_RX_FIFO_CLR_DIS;

/* Only update control register when needed! */
if (mcr_new != mcr_cur)
@@ -439,7 +438,7 @@ static void mtk_mac_link_down(struct phylink_config *config, unsigned int mode,
phylink_config);
u32 mcr = mtk_r32(mac->hw, MTK_MAC_MCR(mac->id));

- mcr &= ~(MAC_MCR_TX_EN | MAC_MCR_RX_EN);
+ mcr &= ~(MAC_MCR_TX_EN | MAC_MCR_RX_EN | MAC_MCR_FORCE_LINK);
mtk_w32(mac->hw, mcr, MTK_MAC_MCR(mac->id));
}

@@ -477,7 +476,7 @@ static void mtk_mac_link_up(struct phylink_config *config,
if (rx_pause)
mcr |= MAC_MCR_FORCE_RX_FC;

- mcr |= MAC_MCR_TX_EN | MAC_MCR_RX_EN;
+ mcr |= MAC_MCR_TX_EN | MAC_MCR_RX_EN | MAC_MCR_FORCE_LINK;
mtk_w32(mac->hw, mcr, MTK_MAC_MCR(mac->id));
}

--
2.43.0