From: Daniel Golle <daniel@xxxxxxxxxxxxxx> [ Upstream commit 6e933a804c7db8be64f367f33e63cd7dcc302ebb ] Only restart auto-negotiation and write link timer if actually necessary. This prevents losing the link in case of minor changes. 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> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/ethernet/mediatek/mtk_sgmii.c | 24 +++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/mediatek/mtk_sgmii.c b/drivers/net/ethernet/mediatek/mtk_sgmii.c index 612f65bb03454..83976dc868875 100644 --- a/drivers/net/ethernet/mediatek/mtk_sgmii.c +++ b/drivers/net/ethernet/mediatek/mtk_sgmii.c @@ -38,20 +38,16 @@ static int mtk_pcs_config(struct phylink_pcs *pcs, unsigned int mode, const unsigned long *advertising, bool permit_pause_to_mac) { + bool mode_changed = false, changed, use_an; struct mtk_pcs *mpcs = pcs_to_mtk_pcs(pcs); unsigned int rgc3, sgm_mode, bmcr; int advertise, link_timer; - bool changed, use_an; advertise = phylink_mii_c22_pcs_encode_advertisement(interface, advertising); if (advertise < 0) return advertise; - link_timer = phylink_get_link_timer_ns(interface); - if (link_timer < 0) - return link_timer; - /* Clearing IF_MODE_BIT0 switches the PCS to BASE-X mode, and * we assume that fixes it's speed at bitrate = line rate (in * other words, 1000Mbps or 2500Mbps). @@ -77,13 +73,16 @@ static int mtk_pcs_config(struct phylink_pcs *pcs, unsigned int mode, } if (use_an) { - /* FIXME: Do we need to set AN_RESTART here? */ - bmcr = SGMII_AN_RESTART | SGMII_AN_ENABLE; + bmcr = SGMII_AN_ENABLE; } else { bmcr = 0; } if (mpcs->interface != interface) { + link_timer = phylink_get_link_timer_ns(interface); + if (link_timer < 0) + return link_timer; + /* PHYA power down */ regmap_update_bits(mpcs->regmap, SGMSYS_QPHY_PWR_STATE_CTRL, SGMII_PHYA_PWD, SGMII_PHYA_PWD); @@ -101,16 +100,17 @@ static int mtk_pcs_config(struct phylink_pcs *pcs, unsigned int mode, regmap_update_bits(mpcs->regmap, mpcs->ana_rgc3, RG_PHY_SPEED_3_125G, rgc3); + /* Setup the link timer */ + regmap_write(mpcs->regmap, SGMSYS_PCS_LINK_TIMER, link_timer / 2 / 8); + mpcs->interface = interface; + mode_changed = true; } /* Update the advertisement, noting whether it has changed */ regmap_update_bits_check(mpcs->regmap, SGMSYS_PCS_ADVERTISE, SGMII_ADVERTISE, advertise, &changed); - /* Setup the link timer and QPHY power up inside SGMIISYS */ - regmap_write(mpcs->regmap, SGMSYS_PCS_LINK_TIMER, link_timer / 2 / 8); - /* Update the sgmsys mode register */ regmap_update_bits(mpcs->regmap, SGMSYS_SGMII_MODE, SGMII_REMOTE_FAULT_DIS | SGMII_SPEED_DUPLEX_AN | @@ -118,7 +118,7 @@ static int mtk_pcs_config(struct phylink_pcs *pcs, unsigned int mode, /* Update the BMCR */ regmap_update_bits(mpcs->regmap, SGMSYS_PCS_CONTROL_1, - SGMII_AN_RESTART | SGMII_AN_ENABLE, bmcr); + SGMII_AN_ENABLE, bmcr); /* Release PHYA power down state * Only removing bit SGMII_PHYA_PWD isn't enough. @@ -132,7 +132,7 @@ static int mtk_pcs_config(struct phylink_pcs *pcs, unsigned int mode, usleep_range(50, 100); regmap_write(mpcs->regmap, SGMSYS_QPHY_PWR_STATE_CTRL, 0); - return changed; + return changed || mode_changed; } static void mtk_pcs_restart_an(struct phylink_pcs *pcs) -- 2.39.2