From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dinh Nguyen Subject: Re: SoCFPGA ethernet broken Date: Thu, 15 Oct 2015 15:49:28 -0500 Message-ID: <56201158.8040806@opensource.altera.com> References: <561FF9E2.30102@opensource.altera.com> <56200687.9040903@gmail.com> <562005AD.8020903@opensource.altera.com> <56200BD7.8020505@gmail.com> <56200E15.9080603@caviumnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: "David S. Miller" , , , "linux-kernel@vger.kernel.org" To: David Daney , Florian Fainelli Return-path: In-Reply-To: <56200E15.9080603@caviumnetworks.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 10/15/2015 03:35 PM, David Daney wrote: > On 10/15/2015 01:25 PM, Florian Fainelli wrote: >> On 15/10/15 12:59, Dinh Nguyen wrote: >>> On 10/15/2015 03:03 PM, Florian Fainelli wrote: >>>> On 15/10/15 12:09, Dinh Nguyen wrote: >>>>> Hi, >>>>> >>>>> commit "8b63ec1837fa phylib: Make PHYs children of their MDIO bus, not >>>>> the bus' parent." seems to have broken ethernet support for the >>>>> SoCFPGA >>>>> platform which is using the stmmac ethernet driver. >>>> >>>> It is not clear to me how this relates to what you are seeing yet. >>>> >>>>> >>>>> It appears that during DHCP, it cannot get an IP address. This only >>>>> happens if ethernet was not used by the bootloader to tftp an kernel >>>>> image. If I use the bootloader to tftp an image then ethernet is >>>>> working >>>>> fine. So I think the PHY is not getting enabled properly. >>>>> >>>>> If I revert this patch, then ethernet is back to working on the >>>>> platform. >>>> >>>> Is the Device Tree source for this platform available somewhere to >>>> look at? >>>> >>> >>> Yes, I'm using the DTS that is in the mainline: >>> >>> arch/arm/boot/dts/socfpga.dtsi >>> arch/arm/boot/dts/socfpga_cyclone5.dtsi >>> arch/arm/boot/dts/socfpga_cyclone5_socdk.dts >> >> There are no PHY devices in any of these DTS files, instead there is the >> non-standard "phy-addr" property which is set to 0xffffffff supposedly >> to indicate that the MDIO bus should be scanned. This is likely part of >> your problem. The stmmac driver seems to be looking for "snps,phy-addr" >> and not "phy-addr", so I am not even clear how this is supposed to work, >> and the driver mentions this custom property is deprecated anyway. >> > > I think it is OK not to expose the PHYs in the device tree if they can > be accurately probed without knowing information from the device tree. > >> The core problem is in >> drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c::stmmac_mdio_register >> which manually detects the PHY, that is mostly fine, except that it does >> not really seem to work here for a reason that is still unclear to me. >> > > I agree with this analysis. I have also been looking at the code and > cannot see anything that depends on what the parent device of the PHY > is. So it is a bit mystifying. > > > I noticed in your original message you had in the boot log this: > > . > . > . > [ 0.804992] libphy: stmmac: probed > [ 0.808410] eth0: PHY ID 00221611 at 4 IRQ POLL (stmmac-0:04) active > . > . > . > > Does this text change with and without the 8b63ec1837fa patch? No, this text does not change with/without the 8b63ec1837fa patch. Dinh