On Thu, 10 Jul 2014 10:46:21 -0700 Florian Fainelli <f.fainelli@xxxxxxxxx> wrote: > 2014-07-10 10:19 GMT-07:00 Boris BREZILLON <boris.brezillon@xxxxxxxxxxxxxxxxxx>: > > On Thu, 10 Jul 2014 08:35:15 -0700 > > Florian Fainelli <f.fainelli@xxxxxxxxx> wrote: > > > >> 2014-07-10 2:07 GMT-07:00 Boris BREZILLON <boris.brezillon@xxxxxxxxxxxxxxxxxx>: > >> > On Fri, 27 Jun 2014 09:52:56 +0200 > >> > Nicolas Ferre <nicolas.ferre@xxxxxxxxx> wrote: > >> > > >> >> On 26/06/2014 22:01, Boris BREZILLON : > >> >> > Hi Florian, > >> >> > > >> >> > On 26/06/2014 20:15, Florian Fainelli wrote: > >> >> >> Hi Boris, > >> >> >> > >> >> >> 2014-06-26 3:13 GMT-07:00 Boris BREZILLON <boris.brezillon@xxxxxxxxxxxxxxxxxx>: > >> >> >>> Add ethernet-phy node and specify phy interrupt (connected to pin PB25). > >> >> >>> > >> >> >>> The PHY address is not specified here because atmel have 2 different > >> >> >>> designs > >> >> >>> for its CPU modules: one is connecting PHYAD[0-2] pins to pull up resistors > >> >> >>> (Embest design) and the other one is connection PHYAD0 to a pull up > >> >> >>> resistor and PHYAD[1-2] to pull down resistors (Ronetix design). > >> >> >>> As a result, Ronetix design will have its PHY available at address 0x1 and > >> >> >>> Embest design at 0x7. > >> >> >>> Let the net PHY core automatically detect the PHY address by scanning the > >> >> >>> MDIO bus. > >> >> >> I though the compatible string was listed as a required property, but > >> >> >> it is not. The 'reg' property however is listed as required, although > >> >> >> the of_miodbus_register() works just fine without it, although that is > >> >> >> a Linux-specific implementation detail. > >> >> > > >> >> > Indeed, it's listed in the required property list of the DT binding doc, > >> >> > but the code implement auto detection if reg is missing. > >> >> > However this line [1] clearly shows that specifying the reg property is > >> >> > the preferred way of doing things. > >> >> > > >> >> > I could define 2 different sama5d3xcm.dtsi (sama5d3xcm-ronetix.dtsi and > >> >> > sama5d3xcm-embest.dtsi) to avoid this dirty hack, > >> >> > but then we would have 2 more dtb and the user would have to determine > >> >> > which CPU module he owns to choose the appropriate dtb. > >> >> > If at91, arm-soc and DT maintainers agree with this approach I can > >> >> > definitely propose something. > >> >> > >> >> Yes Boris, I definitively prefer not to add another .dtsi file for this > >> >> series if we can avoid it. > >> >> > >> > > >> > Okay, now that I don't specify the reg property I have a bunch of > >> > noisy logs (which is exactly what the developer of of_mdio.c wanted in > >> > order to force people to specify the reg property). > >> > > >> > It seems to be a problem for atmel users (all these logs make them > >> > think there is something wrong with the net device). > >> > > >> > Apart from the dts/dtsi split solution, which Nicolas wants to avoid, I > >> > see two solutions here: > >> > > >> > 1) remove the logs (or use dev_dbg instead of dev_info) from of_mdio.c. > >> > But I'm pretty sure this solution won't be accepted :-). > >> > >> I am fine with using dev_dbg() instead of dev_info() for that sort of > >> messages, provided that you state the rationale of this change > >> (spewing the log console with probing messages) and specify tha the > >> 'reg' property is optional. > >> > >> > > >> > 2) define 2 ethernet phys (one for each possible solution). I tested it > >> > and it works fine (only the available PHY is registered and there is no > >> > noisy logs anymore). > >> > >> One advantage of that solution is that you'll get slightly faster boot > >> times since you won't have to auto-probe for the PHYs on the MDIO bus, > >> the time savings get bigger as you start using higher PHY addresses. > > > > Yes I prefer this solution too, but is it acceptable to define 2 phy > > nodes even if only one is really available ? > > One or the other machine .dts should have to set the status property > accordingly so there is only effectively one PHY declared, assuming > this is possible based on your .dtsi layout? This is exactly what Nicolas wants to avoid (duplication of dts files to handle Embest and Ronetix designs). > If not, provided by the > phy-handle properties are correct, I can't see any problem with having > an unused PHY specified in DT. Okay, then I'll go for that solution. Thanks, Boris -- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com -- 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
