NAND-tree is used to check wiring between MAC and PHY using NAND gates on the PHY side, hence the name.
NAND-tree initial status is latched at reset by probing the IRQ pin. However some devices are sharing the PHY IRQ pin with other peripherals such as Atmel SAMA5D[34]x-EK boards when using the optional TM7000 display module, therefore they are switching the PHY in NAND-tree test mode depending on the current IRQ line status at reset.
This patch ensure PHY is not in NAND-tree test mode only for the Micrel KSZ8051 PHY used by Atmel. There are other Micrel PHY affected but I doubt they are used on such weird hardware design.
Signed-off-by: Sylvain Rochet sylvain.rochet@finsecur.com --- drivers/net/phy/micrel.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+)
diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c index 507b9a3..a4a0efa 100644 --- a/drivers/net/phy/micrel.c +++ b/drivers/net/phy/micrel.c @@ -22,6 +22,34 @@ static struct phy_driver KSZ804_driver = { .shutdown = &genphy_shutdown, };
+/** + * KSZ8051 + */ +#define MII_KSZ8051_PHY_OMSO 0x16 +#define MII_KSZ8051_PHY_OMSO_NAND_TREE_ON (1 << 5) + +static int ksz8051_config(struct phy_device *phydev) +{ + unsigned val; + + /* Disable NAND-tree */ + val = phy_read(phydev, MDIO_DEVAD_NONE, MII_KSZ8051_PHY_OMSO); + val &= ~MII_KSZ8051_PHY_OMSO_NAND_TREE_ON; + phy_write(phydev, MDIO_DEVAD_NONE, MII_KSZ8051_PHY_OMSO, val); + + return genphy_config(phydev); +} + +static struct phy_driver KSZ8051_driver = { + .name = "Micrel KSZ8051", + .uid = 0x221550, + .mask = 0xfffff0, + .features = PHY_BASIC_FEATURES, + .config = &ksz8051_config, + .startup = &genphy_startup, + .shutdown = &genphy_shutdown, +}; + #ifndef CONFIG_PHY_MICREL_KSZ9021 /* * I can't believe Micrel used the exact same part number @@ -215,6 +243,7 @@ static struct phy_driver ksz9031_driver = { int phy_micrel_init(void) { phy_register(&KSZ804_driver); + phy_register(&KSZ8051_driver); #ifdef CONFIG_PHY_MICREL_KSZ9021 phy_register(&ksz9021_driver); #else