From f62265b53ef34a372b657c99e23d32e95b464316 Mon Sep 17 00:00:00 2001 From: Zefir Kurtisi Date: Mon, 24 Oct 2016 12:40:54 +0200 Subject: [PATCH] at803x: double check SGMII side autoneg In SGMII mode, we observed an autonegotiation issue after power-down-up cycles where the copper side reports successful link establishment but the SGMII side's link is down. This happened in a setup where the at8031 is connected over SGMII to a eTSEC (fsl gianfar), but so far could not be reproduced with other Ethernet device / driver combinations. This commit adds a wrapper function for at8031 that in case of operating in SGMII mode double checks SGMII link state when generic aneg_done() succeeds. It prints a warning on failure but intentionally does not try to recover from this state. As a result, if you ever see a warning '803x_aneg_done: SGMII link is not ok' you will end up having an Ethernet link up but won't get any data through. This should not happen, if it does, please contact the module maintainer. Signed-off-by: Zefir Kurtisi Signed-off-by: David S. Miller --- drivers/net/phy/at803x.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c index cf74d108953e..a52b560e428b 100644 --- a/drivers/net/phy/at803x.c +++ b/drivers/net/phy/at803x.c @@ -42,10 +42,18 @@ #define AT803X_MMD_ACCESS_CONTROL 0x0D #define AT803X_MMD_ACCESS_CONTROL_DATA 0x0E #define AT803X_FUNC_DATA 0x4003 +#define AT803X_REG_CHIP_CONFIG 0x1f +#define AT803X_BT_BX_REG_SEL 0x8000 #define AT803X_DEBUG_ADDR 0x1D #define AT803X_DEBUG_DATA 0x1E +#define AT803X_MODE_CFG_MASK 0x0F +#define AT803X_MODE_CFG_SGMII 0x01 + +#define AT803X_PSSR 0x11 /*PHY-Specific Status Register*/ +#define AT803X_PSSR_MR_AN_COMPLETE 0x0200 + #define AT803X_DEBUG_REG_0 0x00 #define AT803X_DEBUG_RX_CLK_DLY_EN BIT(15) @@ -355,6 +363,36 @@ static void at803x_link_change_notify(struct phy_device *phydev) } } +static int at803x_aneg_done(struct phy_device *phydev) +{ + int ccr; + + int aneg_done = genphy_aneg_done(phydev); + if (aneg_done != BMSR_ANEGCOMPLETE) + return aneg_done; + + /* + * in SGMII mode, if copper side autoneg is successful, + * also check SGMII side autoneg result + */ + ccr = phy_read(phydev, AT803X_REG_CHIP_CONFIG); + if ((ccr & AT803X_MODE_CFG_MASK) != AT803X_MODE_CFG_SGMII) + return aneg_done; + + /* switch to SGMII/fiber page */ + phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr & ~AT803X_BT_BX_REG_SEL); + + /* check if the SGMII link is OK. */ + if (!(phy_read(phydev, AT803X_PSSR) & AT803X_PSSR_MR_AN_COMPLETE)) { + pr_warn("803x_aneg_done: SGMII link is not ok\n"); + aneg_done = 0; + } + /* switch back to copper page */ + phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr | AT803X_BT_BX_REG_SEL); + + return aneg_done; +} + static struct phy_driver at803x_driver[] = { { /* ATHEROS 8035 */ @@ -406,6 +444,7 @@ static struct phy_driver at803x_driver[] = { .flags = PHY_HAS_INTERRUPT, .config_aneg = genphy_config_aneg, .read_status = genphy_read_status, + .aneg_done = at803x_aneg_done, .ack_interrupt = &at803x_ack_interrupt, .config_intr = &at803x_config_intr, } }; -- 2.20.1