The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 90702dcd19c093621b422ba16fcfd870afe2552f Mon Sep 17 00:00:00 2001
From: Joakim Zhang qiangqing.zhang@nxp.com Date: Tue, 7 Sep 2021 18:56:47 +0800 Subject: [PATCH] net: stmmac: fix MAC not working when system resume back with WoL active
We can reproduce this issue with below steps: 1) enable WoL on the host 2) host system suspended 3) remote client send out wakeup packets We can see that host system resume back, but can't work, such as ping failed.
After a bit digging, this issue is introduced by the commit 46f69ded988d ("net: stmmac: Use resolved link config in mac_link_up()"), which use the finalised link parameters in mac_link_up() rather than the parameters in mac_config().
There are two scenarios for MAC suspend/resume in STMMAC driver:
1) MAC suspend with WoL inactive, stmmac_suspend() call phylink_mac_change() to notify phylink machine that a change in MAC state, then .mac_link_down callback would be invoked. Further, it will call phylink_stop() to stop the phylink instance. When MAC resume back, firstly phylink_start() is called to start the phylink instance, then call phylink_mac_change() which will finally trigger phylink machine to invoke .mac_config and .mac_link_up callback. All is fine since configuration in these two callbacks will be initialized, that means MAC can restore the state.
2) MAC suspend with WoL active, phylink_mac_change() will put link down, but there is no phylink_stop() to stop the phylink instance, so it will link up again, that means .mac_config and .mac_link_up would be invoked before system suspended. After system resume back, it will do DMA initialization and SW reset which let MAC lost the hardware setting (i.e MAC_Configuration register(offset 0x0) is reset). Since link is up before system suspended, so .mac_link_up would not be invoked after system resume back, lead to there is no chance to initialize the configuration in .mac_link_up callback, as a result, MAC can't work any longer.
After discussed with Russell King [1], we confirm that phylink framework have not take WoL into consideration yet. This patch calls phylink_suspend()/phylink_resume() functions which is newly introduced by Russell King to fix this issue.
[1] https://lore.kernel.org/netdev/20210901090228.11308-1-qiangqing.zhang@nxp.co...
Fixes: 46f69ded988d ("net: stmmac: Use resolved link config in mac_link_up()") Signed-off-by: Joakim Zhang qiangqing.zhang@nxp.com Signed-off-by: David S. Miller davem@davemloft.net
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 97238359e101..ece02b35a6ce 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -7123,8 +7123,6 @@ int stmmac_suspend(struct device *dev) if (!ndev || !netif_running(ndev)) return 0;
- phylink_mac_change(priv->phylink, false); - mutex_lock(&priv->lock);
netif_device_detach(ndev); @@ -7150,14 +7148,6 @@ int stmmac_suspend(struct device *dev) stmmac_pmt(priv, priv->hw, priv->wolopts); priv->irq_wake = 1; } else { - mutex_unlock(&priv->lock); - rtnl_lock(); - if (device_may_wakeup(priv->device)) - phylink_speed_down(priv->phylink, false); - phylink_stop(priv->phylink); - rtnl_unlock(); - mutex_lock(&priv->lock); - stmmac_mac_set(priv, priv->ioaddr, false); pinctrl_pm_select_sleep_state(priv->device); /* Disable clock in case of PWM is off */ @@ -7171,6 +7161,16 @@ int stmmac_suspend(struct device *dev)
mutex_unlock(&priv->lock);
+ rtnl_lock(); + if (device_may_wakeup(priv->device) && priv->plat->pmt) { + phylink_suspend(priv->phylink, true); + } else { + if (device_may_wakeup(priv->device)) + phylink_speed_down(priv->phylink, false); + phylink_suspend(priv->phylink, false); + } + rtnl_unlock(); + if (priv->dma_cap.fpesel) { /* Disable FPE */ stmmac_fpe_configure(priv, priv->ioaddr, @@ -7261,13 +7261,15 @@ int stmmac_resume(struct device *dev) return ret; }
- if (!device_may_wakeup(priv->device) || !priv->plat->pmt) { - rtnl_lock(); - phylink_start(priv->phylink); - /* We may have called phylink_speed_down before */ - phylink_speed_up(priv->phylink); - rtnl_unlock(); + rtnl_lock(); + if (device_may_wakeup(priv->device) && priv->plat->pmt) { + phylink_resume(priv->phylink); + } else { + phylink_resume(priv->phylink); + if (device_may_wakeup(priv->device)) + phylink_speed_up(priv->phylink); } + rtnl_unlock();
rtnl_lock(); mutex_lock(&priv->lock); @@ -7288,8 +7290,6 @@ int stmmac_resume(struct device *dev) mutex_unlock(&priv->lock); rtnl_unlock();
- phylink_mac_change(priv->phylink, true); - netif_device_attach(ndev);
return 0;