diff options
| -rw-r--r-- | drivers/net/phy/mxl-gpy.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/drivers/net/phy/mxl-gpy.c b/drivers/net/phy/mxl-gpy.c index 24bae27eedef..cae24091fb6f 100644 --- a/drivers/net/phy/mxl-gpy.c +++ b/drivers/net/phy/mxl-gpy.c @@ -9,6 +9,7 @@ #include <linux/module.h> #include <linux/bitfield.h> #include <linux/hwmon.h> +#include <linux/mutex.h> #include <linux/phy.h> #include <linux/polynomial.h> #include <linux/netdevice.h> @@ -70,6 +71,14 @@ #define VPSPEC1_TEMP_STA 0x0E #define VPSPEC1_TEMP_STA_DATA GENMASK(9, 0) +/* Mailbox */ +#define VSPEC1_MBOX_DATA 0x5 +#define VSPEC1_MBOX_ADDRLO 0x6 +#define VSPEC1_MBOX_CMD 0x7 +#define VSPEC1_MBOX_CMD_ADDRHI GENMASK(7, 0) +#define VSPEC1_MBOX_CMD_RD (0 << 8) +#define VSPEC1_MBOX_CMD_READY BIT(15) + /* WoL */ #define VPSPEC2_WOL_CTL 0x0E06 #define VPSPEC2_WOL_AD01 0x0E08 @@ -77,7 +86,13 @@ #define VPSPEC2_WOL_AD45 0x0E0A #define WOL_EN BIT(0) +/* Internal registers, access via mbox */ +#define REG_GPIO0_OUT 0xd3ce00 + struct gpy_priv { + /* serialize mailbox acesses */ + struct mutex mbox_lock; + u8 fw_major; u8 fw_minor; }; @@ -187,6 +202,45 @@ static int gpy_hwmon_register(struct phy_device *phydev) } #endif +static int gpy_mbox_read(struct phy_device *phydev, u32 addr) +{ + struct gpy_priv *priv = phydev->priv; + int val, ret; + u16 cmd; + + mutex_lock(&priv->mbox_lock); + + ret = phy_write_mmd(phydev, MDIO_MMD_VEND1, VSPEC1_MBOX_ADDRLO, + addr); + if (ret) + goto out; + + cmd = VSPEC1_MBOX_CMD_RD; + cmd |= FIELD_PREP(VSPEC1_MBOX_CMD_ADDRHI, addr >> 16); + + ret = phy_write_mmd(phydev, MDIO_MMD_VEND1, VSPEC1_MBOX_CMD, cmd); + if (ret) + goto out; + + /* The mbox read is used in the interrupt workaround. It was observed + * that a read might take up to 2.5ms. This is also the time for which + * the interrupt line is stuck low. To be on the safe side, poll the + * ready bit for 10ms. + */ + ret = phy_read_mmd_poll_timeout(phydev, MDIO_MMD_VEND1, + VSPEC1_MBOX_CMD, val, + (val & VSPEC1_MBOX_CMD_READY), + 500, 10000, false); + if (ret) + goto out; + + ret = phy_read_mmd(phydev, MDIO_MMD_VEND1, VSPEC1_MBOX_DATA); + +out: + mutex_unlock(&priv->mbox_lock); + return ret; +} + static int gpy_config_init(struct phy_device *phydev) { int ret; @@ -201,6 +255,13 @@ static int gpy_config_init(struct phy_device *phydev) return ret < 0 ? ret : 0; } +static bool gpy_has_broken_mdint(struct phy_device *phydev) +{ + /* At least these PHYs are known to have broken interrupt handling */ + return phydev->drv->phy_id == PHY_ID_GPY215B || + phydev->drv->phy_id == PHY_ID_GPY215C; +} + static int gpy_probe(struct phy_device *phydev) { struct device *dev = &phydev->mdio.dev; @@ -218,6 +279,7 @@ static int gpy_probe(struct phy_device *phydev) if (!priv) return -ENOMEM; phydev->priv = priv; + mutex_init(&priv->mbox_lock); fw_version = phy_read(phydev, PHY_FWV); if (fw_version < 0) @@ -492,6 +554,29 @@ static irqreturn_t gpy_handle_interrupt(struct phy_device *phydev) if (!(reg & PHY_IMASK_MASK)) return IRQ_NONE; + /* The PHY might leave the interrupt line asserted even after PHY_ISTAT + * is read. To avoid interrupt storms, delay the interrupt handling as + * long as the PHY drives the interrupt line. An internal bus read will + * stall as long as the interrupt line is asserted, thus just read a + * random register here. + * Because we cannot access the internal bus at all while the interrupt + * is driven by the PHY, there is no way to make the interrupt line + * unstuck (e.g. by changing the pinmux to GPIO input) during that time + * frame. Therefore, polling is the best we can do and won't do any more + * harm. + * It was observed that this bug happens on link state and link speed + * changes on a GPY215B and GYP215C independent of the firmware version + * (which doesn't mean that this list is exhaustive). + */ + if (gpy_has_broken_mdint(phydev) && + (reg & (PHY_IMASK_LSTC | PHY_IMASK_LSPC))) { + reg = gpy_mbox_read(phydev, REG_GPIO0_OUT); + if (reg < 0) { + phy_error(phydev); + return IRQ_NONE; + } + } + phy_trigger_machine(phydev); return IRQ_HANDLED; |