From 9fe154ee3fd50d3e99a3929c3ff858dda832266c Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Tue, 17 Mar 2020 20:04:54 +0200 Subject: [PATCH] net: phy: dp83867: w/a for fld detect threshold bootstrapping issue [ Upstream commit 749f6f6843115b424680f1aada3c0dd613ad807c ] When the DP83867 PHY is strapped to enable Fast Link Drop (FLD) feature STRAP_STS2.STRAP_ FLD (reg 0x006F bit 10), the Energy Lost Threshold for FLD Energy Lost Mode FLD_THR_CFG.ENERGY_LOST_FLD_THR (reg 0x002e bits 2:0) will be defaulted to 0x2. This may cause the phy link to be unstable. The new DP83867 DM recommends to always restore ENERGY_LOST_FLD_THR to 0x1. Hence, restore default value of FLD_THR_CFG.ENERGY_LOST_FLD_THR to 0x1 when FLD is enabled by bootstrapping as recommended by DM. Signed-off-by: Grygorii Strashko Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/phy/dp83867.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c index 52e8043..31a5595 100644 --- a/drivers/net/phy/dp83867.c +++ b/drivers/net/phy/dp83867.c @@ -25,7 +25,8 @@ #define DP83867_CFG3 0x1e /* Extended Registers */ -#define DP83867_CFG4 0x0031 +#define DP83867_FLD_THR_CFG 0x002e +#define DP83867_CFG4 0x0031 #define DP83867_CFG4_SGMII_ANEG_MASK (BIT(5) | BIT(6)) #define DP83867_CFG4_SGMII_ANEG_TIMER_11MS (3 << 5) #define DP83867_CFG4_SGMII_ANEG_TIMER_800US (2 << 5) @@ -74,6 +75,7 @@ #define DP83867_STRAP_STS2_CLK_SKEW_RX_MASK GENMASK(2, 0) #define DP83867_STRAP_STS2_CLK_SKEW_RX_SHIFT 0 #define DP83867_STRAP_STS2_CLK_SKEW_NONE BIT(2) +#define DP83867_STRAP_STS2_STRAP_FLD BIT(10) /* PHY CTRL bits */ #define DP83867_PHYCR_FIFO_DEPTH_SHIFT 14 @@ -103,6 +105,9 @@ /* CFG4 bits */ #define DP83867_CFG4_PORT_MIRROR_EN BIT(0) +/* FLD_THR_CFG */ +#define DP83867_FLD_THR_CFG_ENERGY_LOST_THR_MASK 0x7 + enum { DP83867_PORT_MIRROING_KEEP, DP83867_PORT_MIRROING_EN, @@ -318,6 +323,20 @@ static int dp83867_config_init(struct phy_device *phydev) phy_clear_bits_mmd(phydev, DP83867_DEVADDR, DP83867_CFG4, BIT(7)); + bs = phy_read_mmd(phydev, DP83867_DEVADDR, DP83867_STRAP_STS2); + if (bs & DP83867_STRAP_STS2_STRAP_FLD) { + /* When using strap to enable FLD, the ENERGY_LOST_FLD_THR will + * be set to 0x2. This may causes the PHY link to be unstable - + * the default value 0x1 need to be restored. + */ + ret = phy_modify_mmd(phydev, DP83867_DEVADDR, + DP83867_FLD_THR_CFG, + DP83867_FLD_THR_CFG_ENERGY_LOST_THR_MASK, + 0x1); + if (ret) + return ret; + } + if (phy_interface_is_rgmii(phydev)) { val = phy_read(phydev, MII_DP83867_PHYCTRL); if (val < 0) -- 2.7.4