On 03.09.2020 10:41, Petr Tesarik wrote: > Hi Heiner, > > this issue was on the back-burner for some time, but I've got some > interesting news now. > > On Sat, 18 Jul 2020 14:07:50 +0200 > Heiner Kallweit <hkallwe...@gmail.com> wrote: > >> [...] >> Maybe the following gives us an idea: >> Please do "ethtool -d <if>" after boot and after resume from suspend, >> and check for differences. > > The register dump did not reveal anything of interest - the only > differences were in the physical addresses after a device reopen. > > However, knowing that reloading the driver can fix the issue, I copied > the initialization sequence from init_one() to rtl8169_resume() and > gave it a try. That works! > > Then I started removing the initialization calls one by one. This > exercise left me with a call to rtl_init_rxcfg(), which simply sets the > RxConfig register. In other words, these is the difference between > 5.8.4 and my working version: > > --- linux-orig/drivers/net/ethernet/realtek/r8169_main.c 2020-09-02 > 22:43:09.361951750 +0200 > +++ linux/drivers/net/ethernet/realtek/r8169_main.c 2020-09-03 > 10:36:23.915803703 +0200 > @@ -4925,6 +4925,9 @@ > > clk_prepare_enable(tp->clk); > > + if (tp->mac_version == RTL_GIGA_MAC_VER_37) > + RTL_W32(tp, RxConfig, RX128_INT_EN | RX_DMA_BURST); > + > if (netif_running(tp->dev)) > __rtl8169_resume(tp); > > This is quite surprising, at least when the device is managed by > NetworkManager, because then it is closed on wakeup, and the open > method should call rtl_init_rxcfg() anyway. So, it might be a timing > issue, or incorrect order of register writes. > Thanks for the analysis. If you manually bring down and up the interface, do you see the same issue? What is the value of RxConfig when entering the resume function?
> Since I have no idea why the above change fixes my issue, I'm hesitant > to post it as a patch. It might break other people's systems... > > Petr T > Heiner
