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
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