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. > > Could net and DT maintainers help us choose the best solution (or > propose a new one) ? > > Best Regards, > > Boris > > -- > Boris Brezillon, Free Electrons > Embedded Linux and Kernel engineering > http://free-electrons.com -- 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
