From: Andrew Glen <[email protected]> Reply-To: "[email protected]" <[email protected]> Date: Monday, November 3, 2014 at 11:36 PM To: "[email protected]" <[email protected]> Subject: Re: [beagleboard] Re: Beaglebone Black Ethernet Phy Not Detected on Boot.
> > Yes, and reading the thread even more fully you'll find my report of running > thousands of automated test restarts with these parts removed, with a 100% > success rate. > > We use these boards a lot, running 24-7 in this configuration, and have had > zero hardware faults. With any luck we have nearly exhausted Murphy's law with > our software. Hi Andrew, I accept that you have done these tests, but removing test two capacitors from the reset line means the device will come out of reset before the power supply has stabilized and without a capacitor, the reset switch will bounce several times. That is not a good idea. Perhaps you are just lucky given your setup, but removing C24 and C30 is a bad idea. Making these capacitors smaller may fix your problem but I suggest that you do have something there to delay the reset line. Regards, John > Andrew. > > On 4/11/2014 7:26 PM, "John Syn" <[email protected]> wrote: >> >> From: Andrew Glen <[email protected]> >> Reply-To: "[email protected]" <[email protected]> >> Date: Monday, November 3, 2014 at 9:42 PM >> To: "[email protected]" <[email protected]> >> Subject: Re: [beagleboard] Re: Beaglebone Black Ethernet Phy Not Detected on >> Boot. >> >>> >>> As far as I know, and as already documented in this thread, the only >>> reliable fix is to remove C24 and C30. >> >> If you read the full thread, Gerald say that if you remove these capacitors, >> the board may not start at all. >> >> Regards, >> John >>> On 4/11/2014 5:40 PM, "Jerin George" <[email protected]> wrote: >>>> Hi, >>>> I am using a BBB Rev C with latest Angstrom image and i have seen this >>>> issue with eth not getting detected at boot up. This came at the last >>>> stages of my project delivery. How can this be corrected. Does moving to >>>> the latest debian image solves this issue ? >>>> >>>> regards, >>>> Jerin George >>>> >>>> On Saturday, 26 July 2014 04:31:42 UTC+5:30, [email protected] wrote: >>>>> >>>>> They phymask comes from a hardware register read by the davinci_mdio >>>>> driver, which gets passed to the linux phy libraries. The problem is that >>>>> the cpsw driver gets the value from device tree, which is hardcoded to >>>>> address 0. Usually the values are the same (address 0), but sometimes the >>>>> phy gets registered to a different address, usually in my case address 2. >>>>> You calculate the address using the phymask. If you changed the phymask >>>>> than, you pointing back to address 0, so that wouldn't help you. >>>>> >>>>> I rebuilt the dtb file. >>>>> >>>>> On Thursday, July 24, 2014 4:10:18 PM UTC-4, Loren Amelang wrote: >>>>>> On Wednesday, July 23, 2014 3:54:00 PM UTC-7, [email protected] wrote: >>>>>>> The davinci mdio driver should report a phymask and that value is used >>>>>>> to update the device tree. >>>>>> >>>>>> Back when I had this problem I tried hard to find out where the phymask >>>>>> comes from, and never succeeded. At that time people who received a >>>>>> phymask of fffffffe booted successfully, those with fffffffb failed. Do >>>>>> you know where the mask is found and how to change it? >>>>>> >>>>>>> I also remove the second phy slave from the device tree. >>>>>> >>>>>> That seems like a great idea, if only to stop all the useless messages >>>>>> about it never being found. Can that be done in the uEnv.txt, like when >>>>>> you disable HDMI, or do you have to rebuild the device tree binary? Would >>>>>> setting the phymask to ffffffff accomplish the same thing? >>>>>> >>>>>> Loren >>>> -- >>>> For more options, visit http://beagleboard.org/discuss >>>> --- >>>> You received this message because you are subscribed to a topic in the >>>> Google Groups "BeagleBoard" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/beagleboard/9mctrG26Mc8/unsubscribe. >>>> To unsubscribe from this group and all its topics, send an email to >>>> [email protected]. >>>> For more options, visit https://groups.google.com/d/optout. >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google Groups >>> "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send an >>> email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to a topic in the Google >> Groups "BeagleBoard" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/beagleboard/9mctrG26Mc8/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> For more options, visit https://groups.google.com/d/optout. > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
