Reset the internal PCS state machine when changing interface mode.
This prevents confusing the state machine when changing interface
modes, e.g. from SGMII to 2500Base-X or vice-versa.
Fixes: 7e538372694b ("net: ethernet: mediatek: Re-add support SGMII")
Reviewed-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
Tested-by: Bjørn Mork <bjorn@xxxxxxx>
Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.h | 4 ++++
drivers/net/ethernet/mediatek/mtk_sgmii.c | 4 ++++
2 files changed, 8 insertions(+)
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index b65de174c3d9..084a6badef6d 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -542,6 +542,10 @@
#define SGMII_SEND_AN_ERROR_EN BIT(11)
#define SGMII_IF_MODE_MASK GENMASK(5, 1)
+/* Register to reset SGMII design */
+#define SGMII_RESERVED_0 0x34
+#define SGMII_SW_RESET BIT(0)
+
/* Register to set SGMII speed, ANA RG_ Control Signals III*/
#define SGMSYS_ANA_RG_CS3 0x2028
#define RG_PHY_SPEED_MASK (BIT(2) | BIT(3))
diff --git a/drivers/net/ethernet/mediatek/mtk_sgmii.c b/drivers/net/ethernet/mediatek/mtk_sgmii.c
index bb00de1003ac..612f65bb0345 100644
--- a/drivers/net/ethernet/mediatek/mtk_sgmii.c
+++ b/drivers/net/ethernet/mediatek/mtk_sgmii.c
@@ -88,6 +88,10 @@ static int mtk_pcs_config(struct phylink_pcs *pcs, unsigned int mode,
regmap_update_bits(mpcs->regmap, SGMSYS_QPHY_PWR_STATE_CTRL,
SGMII_PHYA_PWD, SGMII_PHYA_PWD);
+ /* Reset SGMII PCS state */
+ regmap_update_bits(mpcs->regmap, SGMII_RESERVED_0,
+ SGMII_SW_RESET, SGMII_SW_RESET);
+
if (interface == PHY_INTERFACE_MODE_2500BASEX)
rgc3 = RG_PHY_SPEED_3_125G;
else
--
2.39.2
