path: root/reference
529ed12752635ba8a35dc78ec70ed6f42570b4ca'>patch) tree62b3b955eac47a91d0273653b150af712168272a parentfba40c632c6473fa89660e870a6042c0fe733f8c (diff)
net: phy: phy drivers should not set SUPPORTED_[Asym_]Pause
Instead of having individual PHY drivers set the SUPPORTED_Pause and SUPPORTED_Asym_Pause flags, phylib itself should set those flags, unless there is a hardware erratum or other special case. During autonegotiation, the PHYs will determine whether to enable pause frame support. Pause frames are a feature that is supported by the MAC. It is the MAC that generates the frames and that processes them. The PHY can only be configured to allow them to pass through. This commit also effectively reverts the recently applied c7a61319 ("net: phy: dp83848: Support ethernet pause frames"). So the new process is: 1) Unless the PHY driver overrides it, phylib sets the SUPPORTED_Pause and SUPPORTED_AsymPause bits in phydev->supported. This indicates that the PHY supports pause frames. 2) The MAC driver checks phydev->supported before it calls phy_start(). If (SUPPORTED_Pause | SUPPORTED_AsymPause) is set, then the MAC driver sets those bits in phydev->advertising, if it wants to enable pause frame support. 3) When the link state changes, the MAC driver checks phydev->pause and phydev->asym_pause, If the bits are set, then it enables the corresponding features in the MAC. The algorithm is: if (phydev->pause) The MAC should be programmed to receive and honor pause frames it receives, i.e. enable receive flow control. if (phydev->pause != phydev->asym_pause) The MAC should be programmed to transmit pause frames when needed, i.e. enable transmit flow control. Signed-off-by: Timur Tabi <> Signed-off-by: David S. Miller <>
11 files changed, 67 insertions, 90 deletions
diff --git a/drivers/net/phy/bcm-cygnus.c b/drivers/net/phy/bcm-cygnus.c