On Wed, Nov 05, 2014 at 01:04:37PM +0100, Stam, Michel [FINT] wrote: > Hello Charles, > > After looking around I found the reset value for the 8772 chip, which > seems to be 0x1E1 (ANAR register). > > This equates to (according to include/uapi/linux/mii.h) > ADVERTISE_ALL | ADVERTISE_CSMA. > > The register only seems to become 0 if the software reset fails. Odd it definitely reads back as zero on Arndale. I am guessing that the root of the problem here is that for some reason Arndale POR of the ethernet is pants and it needs a full software reset before it will work and the patch removes the full reset callback. > > Unfortunately, this is exactly what I get when the patch is applied; > asix 1-2:1.0 eth1: Failed to send software reset: ffffffb5 > asix 1-2:1.0 eth1: link reset failed (-75) usbnet usb-0000:00:1d.0-2, > ASIX AX88772 USB 2.0 Ethernet > asix 1-2:1.0 eth1: Failed to send software reset: ffffffb5 > asix 1-2:1.0 eth1: link reset failed (-75) usbnet usb-0000:00:1d.0-2, > ASIX AX88772 USB 2.0 Ethernet Ok so I am guessing you have a value in the register which is neither the reset value or 0 and this causing problems later in the reset/on the next reset. I do find the naming confusing in the error message there as it says link reset failed but the link_reset callback can't fail in the driver and I modified the reset callback. But I guess that is just oddities of the network stack I am not familiar with. The other thing that feels odd is (and again apologies as I know next to nothing about the networking stack) how come it is unexpected that the reset callback destroys the state of the device. Naively I would have expected that a reset callback would reset the device back to its default state. Here we seem to be trying to avoid that happening. > > A little while after this its 'Failed to enable software MII access'. > The ethernet device fails to see any link or accept any ethtool -s > command. > > My device has vid:devid 0b95:772a (ASIX Elec. Corp.). > > Can you tell me what device is on the Andale platform, Charles? Same > vendor/device id? Yeah mine also idVendor=0b95, idProduct=772a Thanks, Charles > > Another thing that bothers me is that dev->mii.advertising seems to > contain the same value, so maybe that can be used instead of a call to > asix_mdio_read(). Can anyone comment on its purpose? Should it be a > shadow copy of the real register or something? > > Riku, can you test Charles' patch as well? > > Kind regards, > > Michel Stam > > -----Original Message----- > From: Charles Keepax [mailto:ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx] > Sent: Tuesday, November 04, 2014 21:09 PM > To: Stam, Michel [FINT] > Cc: Riku Voipio; davem@xxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; > netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > linux-samsung-soc@xxxxxxxxxxxxxxx > Subject: Re: "asix: Don't reset PHY on if_up for ASIX 88772" breaks net > onarndale platform > > On Tue, Nov 04, 2014 at 11:23:06AM +0100, Stam, Michel [FINT] wrote: > > Hello Riku, > > > > >Fixing a bug (ethtool support) must not cause breakage elsewhere (in > > this case on arndale). This is now a regression of functionality from > > 3.17. > > > > > >I think it would better to revert the change now and with less hurry > > introduce a ethtool fix that doesn't break arndale. > > > > I don't fully agree here; > > I would like to point out that this commit is a revert itself. Fixing > > the armdale will then cause breakage in other implementations, such as > > > ours. Blankly reverting breaks other peoples' implementations. > > > > The PHY reset is the thing that breaks ethtool support, so any fix > > that appeases all would have to take existing PHY state into account. > > > > I'm not an expert on the ASIX driver, nor the MII, but I think this is > > > the cause; > > drivers/net/usb/asix_devices.c: > > 361 asix_mdio_write(dev->net, dev->mii.phy_id, MII_BMCR, > > BMCR_RESET); > > 362 asix_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE, > > 363 ADVERTISE_ALL | ADVERTISE_CSMA); > > 364 mii_nway_restart(&dev->mii); > > > > I would think that the ADVERTISE_ALL is the cause here, as it will > > reset the MII back to default, thus overriding ethtool settings. > > Would an: > > Int reg; > > reg = asix_mdio_read(dev->net,dev->mii.phy_id,MII_ADVERTISE); > > > > prior to the offending lines, and then; > > > > 362 asix_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE, > > 363 reg); > > > > solve the problem for you guys? > > If I revert the patch in question and add this in: > > --- a/drivers/net/usb/asix_devices.c > +++ b/drivers/net/usb/asix_devices.c > @@ -299,6 +299,7 @@ static int ax88772_reset(struct usbnet *dev) { > struct asix_data *data = (struct asix_data *)&dev->data; > int ret, embd_phy; > + int reg; > u16 rx_ctl; > > ret = asix_write_gpio(dev, > @@ -359,8 +360,10 @@ static int ax88772_reset(struct usbnet *dev) > msleep(150); > > asix_mdio_write(dev->net, dev->mii.phy_id, MII_BMCR, > BMCR_RESET); > - asix_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE, > - ADVERTISE_ALL | ADVERTISE_CSMA); > + reg = asix_mdio_read(dev->net, dev->mii.phy_id, MII_ADVERTISE); > + if (!reg) > + reg = ADVERTISE_ALL | ADVERTISE_CSMA; > + asix_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE, reg); > mii_nway_restart(&dev->mii); > > ret = asix_write_medium_mode(dev, AX88772_MEDIUM_DEFAULT); > > Then things work on Arndale for me. Does that work for you? > Whether that is a sensible fix I don't know however. > > > > > Mind, maybe the read function should take into account the reset value > > > of the MII, and set it to ADVERTISE_ALL | ADVERTISE_CSMA. I don't have > > > any documention here at the moment. > > Yeah I also have no documentation. > > Thanks, > Charles > > > > > Is anyone able to confirm my suspicions? > > > > Kind regards, > > > > Michel Stam > > -----Original Message----- > > From: Riku Voipio [mailto:riku.voipio@xxxxxx] > > Sent: Tuesday, November 04, 2014 10:44 AM > > To: Stam, Michel [FINT] > > Cc: Riku Voipio; davem@xxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; > > netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > > linux-samsung-soc@xxxxxxxxxxxxxxx; ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx > > Subject: Re: "asix: Don't reset PHY on if_up for ASIX 88772" breaks > > net on arndale platform > > > > On Tue, Nov 04, 2014 at 09:19:26AM +0100, Stam, Michel [FINT] wrote: > > > Interesting, as the commit itself is a revert from a kernel back to > > > 2.6 somewhere. The problem I had is related to the PHY being reset > > > on interface-up, can you confirm that you require this? > > > > I can't confirm what exactly is needed on arndale. I'm neither expert > > in USB or ethernet. However, I can confirm that without the PHY reset, > > > networking doesn't work on arndale. > > > > I now see someone else has the same problem, adding Charles to CC. > > > > http://www.spinics.net/lists/linux-usb/msg116656.html > > > > > Reverting this > > > breaks ethtool support in turn. > > > > Fixing a bug (ethtool support) must not cause breakage elsewhere (in > > this case on arndale). This is now a regression of functionality from > > 3.17. > > > > I think it would better to revert the change now and with less hurry > > introduce a ethtool fix that doesn't break arndale. > > > > > Kind regards, > > > > > > Michel Stam > > > > > > -----Original Message----- > > > From: Riku Voipio [mailto:riku.voipio@xxxxxx] > > > Sent: Tuesday, November 04, 2014 8:23 AM > > > To: davem@xxxxxxxxxxxxx; Stam, Michel [FINT] > > > Cc: linux-usb@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; > > > linux-kernel@xxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx > > > Subject: "asix: Don't reset PHY on if_up for ASIX 88772" breaks net > > > on > > > > > arndale platform > > > > > > Hi, > > > > > > With 3.18-rc3, asix on arndale (samsung exynos 5250 based board), > > > fails to work. Interface is initialized but network traffic seem not > > > > to pass through. With kernel IP config the result looks like: > > > > > > [ 3.323275] usb 3-3.2.4: new high-speed USB device number 4 using > > > exynos-ehci > > > [ 3.419151] usb 3-3.2.4: New USB device found, idVendor=0b95, > > > idProduct=772a > > > [ 3.424735] usb 3-3.2.4: New USB device strings: Mfr=1, > Product=2, > > > SerialNumber=3 > > > [ 3.432196] usb 3-3.2.4: Product: AX88772 > > > [ 3.436279] usb 3-3.2.4: Manufacturer: ASIX Elec. Corp. > > > [ 3.441486] usb 3-3.2.4: SerialNumber: 000001 > > > [ 3.447530] asix 3-3.2.4:1.0 (unnamed net_device) > (uninitialized): > > > invalid hw address, using random > > > [ 3.764352] asix 3-3.2.4:1.0 eth0: register 'asix' at > > > usb-12110000.usb-3.2.4, ASIX AX88772 USB 2.0 Ethernet, > > de:a2:66:bf:ca:4f > > > [ 4.488773] asix 3-3.2.4:1.0 eth0: link down > > > [ 5.690025] asix 3-3.2.4:1.0 eth0: link up, 100Mbps, full-duplex, > > lpa > > > 0xC5E1 > > > [ 5.712947] Sending DHCP requests ...... timed out! > > > [ 83.165303] IP-Config: Retrying forever (NFS root)... > > > [ 83.170397] asix 3-3.2.4:1.0 eth0: link up, 100Mbps, full-duplex, > > lpa > > > 0xC5E1 > > > [ 83.192944] Sending DHCP requests ..... > > > > > > Similar results also with dhclient. Git bisect identified the > > > breaking > > > > > commit as: > > > > > > commit 3cc81d85ee01e5a0b7ea2f4190e2ed1165f53c31 > > > Author: Michel Stam <m.stam@xxxxxxxx> > > > Date: Thu Oct 2 10:22:02 2014 +0200 > > > > > > asix: Don't reset PHY on if_up for ASIX 88772 > > > > > > Taking 3.18-rc3 and that commit reverted, network works again: > > > > > > [ 3.303500] usb 3-3.2.4: new high-speed USB device number 4 using > > > exynos-ehci > > > [ 3.399375] usb 3-3.2.4: New USB device found, idVendor=0b95, > > > idProduct=772a > > > [ 3.404963] usb 3-3.2.4: New USB device strings: Mfr=1, > Product=2, > > > SerialNumber=3 > > > [ 3.412424] usb 3-3.2.4: Product: AX88772 > > > [ 3.416508] usb 3-3.2.4: Manufacturer: ASIX Elec. Corp. > > > [ 3.421715] usb 3-3.2.4: SerialNumber: 000001 > > > [ 3.427755] asix 3-3.2.4:1.0 (unnamed net_device) > (uninitialized): > > > invalid hw address, using random > > > [ 3.744837] asix 3-3.2.4:1.0 eth0: register 'asix' at > > > usb-12110000.usb-3.2.4, ASIX AX88772 USB 2.0 Ethernet, > > 12:59:f1:a8:43:90 > > > [ 7.098998] asix 3-3.2.4:1.0 eth0: link up, 100Mbps, full-duplex, > > lpa > > > 0xC5E1 > > > [ 7.118258] Sending DHCP requests ., OK > > > [ 9.753259] IP-Config: Got DHCP answer from 192.168.1.1, my > address > > > is 192.168.1.111 > > > > > > There might something wrong on the samsung platform code (I > > > understand > > > > > the USB on arndale is "funny"), but this is still an regression from > > > > 3.17. > > > > > > Riku -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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