| Message ID | 20180103154629.1433-1-jbrunet@baylibre.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
From: Jerome Brunet <jbrunet@baylibre.com> Date: Wed, 3 Jan 2018 16:46:29 +0100 > Note in the databook - Section 4.4 - EEE : > " The EEE feature is not supported when the MAC is configured to use the > TBI, RTBI, SMII, RMII or SGMII single PHY interface. Even if the MAC > supports multiple PHY interfaces, you should activate the EEE mode only > when the MAC is operating with GMII, MII, or RGMII interface." > > Applying this restriction solves a stability issue observed on Amlogic > gxl platforms operating with RMII interface and the internal PHY. > > Fixes: 83bf79b6bb64 ("stmmac: disable at run-time the EEE if not supported") > Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> > Tested-by: Arnaud Patard <arnaud.patard@rtp-net.org> Applied and queued up for -stable, thanks.
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index c52a9963c19d..023938166821 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -364,9 +364,15 @@ static void stmmac_eee_ctrl_timer(struct timer_list *t) bool stmmac_eee_init(struct stmmac_priv *priv) { struct net_device *ndev = priv->dev; + int interface = priv->plat->interface; unsigned long flags; bool ret = false; + if ((interface != PHY_INTERFACE_MODE_MII) && + (interface != PHY_INTERFACE_MODE_GMII) && + !phy_interface_mode_is_rgmii(interface)) + goto out; + /* Using PCS we cannot dial with the phy registers at this stage * so we do not support extra feature like EEE. */
Note in the databook - Section 4.4 - EEE : " The EEE feature is not supported when the MAC is configured to use the TBI, RTBI, SMII, RMII or SGMII single PHY interface. Even if the MAC supports multiple PHY interfaces, you should activate the EEE mode only when the MAC is operating with GMII, MII, or RGMII interface." Applying this restriction solves a stability issue observed on Amlogic gxl platforms operating with RMII interface and the internal PHY. Fixes: 83bf79b6bb64 ("stmmac: disable at run-time the EEE if not supported") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Tested-by: Arnaud Patard <arnaud.patard@rtp-net.org> --- Hi David, As quickly explained in the log above, we are having some stability issue on Amlogic gxl platform: synopsys MAC + internal PHY over RMII. We found out that these issues are caused by EEE. Forcefully disabling this feature solves our problem. I only had access to a snip of databook. I have no idea if the restriction explained above applies to all the revision of Synopsys MAC controller. Anyway, this change should be safe to apply. If we get more information from Synopsys later on, it will be easy to revert, if necessary. Thanks Jerome Change since RFC [0]: * use phy_interface_mode_is_rgmii() as suggested by Andrew [0]: http://lkml.kernel.org/r/20171205102809.4347-1-jbrunet@baylibre.com drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 6 ++++++ 1 file changed, 6 insertions(+)