On Tue, Dec 10, 2013 at 1:48 AM, Florian Fainelli <f.fainelli@xxxxxxxxx> wrote: > 2013/12/8 Chen-Yu Tsai <wens@xxxxxxxx>: >> Florian, Giuseppe: >> >> On Sat, Dec 7, 2013 at 9:57 AM, Florian Fainelli <f.fainelli@xxxxxxxxx> wrote: >>> 2013/12/6 Chen-Yu Tsai <wens@xxxxxxxx>: >>>> On Sat, Dec 7, 2013 at 5:09 AM, Florian Fainelli <f.fainelli@xxxxxxxxx> wrote: >>>>> 2013/12/6 Chen-Yu Tsai <wens@xxxxxxxx>: >>>>>> The CubieTruck uses the GMAC with an RGMII phy. >>>>>> >>>>>> Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx> >>>>>> --- >>>>>> arch/arm/boot/dts/sun7i-a20-cubietruck.dts | 8 ++++++++ >>>>>> 1 file changed, 8 insertions(+) >>>>>> >>>>>> diff --git a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts >>>>>> index 8a1009d..af212a2 100644 >>>>>> --- a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts >>>>>> +++ b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts >>>>>> @@ -33,6 +33,14 @@ >>>>>> pinctrl-0 = <&uart0_pins_a>; >>>>>> status = "okay"; >>>>>> }; >>>>>> + >>>>>> + gmac: ethernet@01c50000 { >>>>>> + pinctrl-names = "default"; >>>>>> + pinctrl-0 = <&gmac_pins_rgmii>; >>>>>> + snps,phy-addr = <1>; >>>>> >>>>> What is this snps,phy-addr property? Why is not a standard device tree >>>>> node for an Ethernet PHY node used? >>>> >>>> This property is implemented by stmmac and documented in the DT >>>> bindings. stmmac has not been updated to use Ethernet PHY nodes. >>> >>> This driver property should be removed and deprecated since there is >>> an ePAPR standardized Ethernet PHY node. What I am worried here is the >>> loss of information, the standard Ethernet DT node allows to specify >>> much more information (clause, maximum speed, compatible string >>> etc...). >> >> Giuseppe, any thoughts on this? >> >>>> Removing this property will not affect the function of the driver. >>>> The driver probes its MDIO bus and selects the lowest available >>>> address if not specified. >>> >>> So if this is just giving the driver a hint on where to probe for a >>> PHY on the MDIO bus, then let's drop it and use the standard DT node >>> no? >> >> Sure. I will remove it from the DT. >> >> The stmmac driver does not have a seperate MDIO bus driver, nor >> does it support Ethernet PHY node bindings. So I will not add >> a phy node at this moment. > > This will create needless churn in the DT if you do not do it now, > worse actually, we switch from a DT which specifically described > Ethernet PHY nodes properly to a version where it does, to ultimately > a newer version which does. > > Considering that the absence of a "snps,phy-addr" property will still > result in the MDIO bus to be probed, keeping the existing Ethernet PHY > nodes, referencing them correclty with a "phy-handle" property, but > having no explicit support for these in the driver will not result in > a functional change, and will reduce the DT churn. Also, you could > still sneak a patch in this patchset which parses the standard > EThernet PHY node binding. I see. Adding the PHY node should be no trouble at all. Is there a requirement for a seperate mdio bus in the DT? I do not see it in the ePAPR. The stmmac mdio is not a seperate driver, as is for most network controllers I presume. Would attaching the PHY nodes directly under the ethernet controller suffice? We can then introduce PHY node support to the driver and remove the "snps,phy-addr" property at the same time. ChenYu >> >>>>>> + phy-mode = "rgmii"; >>>>> >>>>> Especially since you use the relatively standard "phy-mode" property here? >>>> >>>> Used as specified in stmmac DT bindings. >>> >>> That one is kind of okay because of_get_phy_mode() knows about it, >>> even though ePAPR states this should be "phy-connection-type", so I am >>> okay with keeping that one because current practice and helpers are >>> here. >> >> It seems all ARM DTs currently use "phy-mode". > > Which is why I said "is kind of okay", but this is not what the > standard came up with, ARM is not exactly the best DT-citizen out > there as people are prone to making up new properties when the > standard already defines some, anyway.... > -- > Florian -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html