On Wed, Feb 26, 2025 at 10:11:58AM +0000, Jon Hunter wrote: > > On 26/02/2025 10:02, Russell King (Oracle) wrote: > > On Tue, Feb 25, 2025 at 02:21:01PM +0000, Jon Hunter wrote: > > > Hi Russell, > > > > > > On 19/02/2025 20:57, Russell King (Oracle) wrote: > > > > So, let's try something (I haven't tested this, and its likely you > > > > will need to work it in to your other change.) > > > > > > > > Essentially, this disables the receive clock stop around the reset, > > > > something the stmmac driver has never done in the past. > > > > > > > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > > > > index 1cbea627b216..8e975863a2e3 100644 > > > > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > > > > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > > > > @@ -7926,6 +7926,8 @@ int stmmac_resume(struct device *dev) > > > > rtnl_lock(); > > > > mutex_lock(&priv->lock); > > > > + phy_eee_rx_clock_stop(priv->dev->phydev, false); > > > > + > > > > stmmac_reset_queues_param(priv); > > > > stmmac_free_tx_skbufs(priv); > > > > @@ -7937,6 +7939,9 @@ int stmmac_resume(struct device *dev) > > > > stmmac_restore_hw_vlan_rx_fltr(priv, ndev, priv->hw); > > > > + phy_eee_rx_clock_stop(priv->dev->phydev, > > > > + priv->phylink_config.eee_rx_clk_stop_enable); > > > > + > > > > stmmac_enable_all_queues(priv); > > > > stmmac_enable_all_dma_irq(priv); > > > > > > > > > Sorry for the delay, I have been testing various issues recently and needed > > > a bit more time to test this. > > > > > > It turns out that what I had proposed last week does not work. I believe > > > that with all the various debug/instrumentation I had added, I was again > > > getting lucky. So when I tested again this week on top of vanilla v6.14-rc2, > > > it did not work :-( > > > > > > However, what you are suggesting above, all by itself, is working. I have > > > tested this on top of vanilla v6.14-rc2 and v6.14-rc4 and it is working > > > reliably. I have also tested on some other boards that use the same stmmac > > > driver (but use the Aquantia PHY) and I have not seen any issues. So this > > > does fix the issue I am seeing. > > > > > > I know we are getting quite late in the rc for v6.14, but not sure if we > > > could add this as a fix? > > > > The patch above was something of a hack, bypassing the layering, so I > > would like to consider how this should be done properly. > > > > I'm still wondering whether the early call to phylink_resume() is > > symptomatic of this same issue, or whether there is a PHY that needs > > phy_start() to be called to output its clock even with link down that > > we don't know about. > > > > The phylink_resume() call is relevant to this because I'd like to put: > > > > phy_eee_rx_clock_stop(priv->dev->phydev, > > priv->phylink_config.eee_rx_clk_stop_enable); > > > > in there to ensure that the PHY is correctly configured for clock-stop, > > but given stmmac's placement that wouldn't work. > > > > I'm then thinking of phylink_pre_resume() to disable the EEE clock-stop > > at the PHY. > > > > I think the only thing we could do is try solving this problem as per > > above and see what the fall-out from it is. I don't get the impression > > that stmmac users are particularly active at testing patches though, so > > it may take months to get breakage reports. > > > We can ask Furong to test as he seems to active and making changes, but > otherwise I am not sure how well it is being tested across various devices. > On the other hand, it feels like there are still lingering issues like this > with the driver and so I would hope this is moving in the right direction. > > Let me know if you have a patch you want me to test and I will run in on our > Tegra186, Tegra194 and Tegra234 devices that all use this. Do we think this needs to be a patch for the net tree or the net-next tree? I think we've established that it's been a long-standing bug, so maybe if we target net-next to give it more time to be tested? -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
