2017-04-03 08:39:16

by Fawad Lateef

[permalink] [raw]
Subject: Suggestions needed for resolving DT issues between kernel 3.10 and 4.4

Hi,

I am facing some issues with device-trees (I am fairly new to them)
and need some pointers about how to approach below problem:

I got some I.MX6Q based hardware (some custom made whose hardware
details are unknown to me). Hardware shipped with 3.10.53 kernel with
full sources and everything is working on it

Trying to get one of the recent kernel working on it (linux-4.4, from
linux-linaro-stable with rt patches). I can compile the kernel and
boot into it using 3.10.xx kernel compiled DTB but getting Warning at
boot-time "Outdated DT detected, suspend/resume will NOT work" and few
main hardware components not working (mainly ethernet(s) - 1 out of 4
ports working though, MTD/NAND (for u-boot environment))

So I looked into compiling the DTS (from 3.10 kernel) for 4.4 and
managed to get it compiled. Now no warning of outdated DT _but_ still
hardware components not working.

I was assuming that as hardware is still same for both kernel 3.10 and
4.4, so it should work, but seems like something in DT is off for 4.4
kernel.

Any help and suggestions will be good enough for me to look into above issue.

Thanks and regards,

-- Fawad Lateef


2017-04-03 08:55:11

by Fawad Lateef

[permalink] [raw]
Subject: Re: Suggestions needed for resolving DT issues between kernel 3.10 and 4.4

Hi,

One more thing I realised that eth0 which is working is directly out
of SOM/SOC but other 3 eth ports are connected to a internal USB
switch (so Linux should see only eth1 besides eth0).

So seems like flash/nand chip (m25p80) and spi_ks8995 (Micrel KS8995
Ethernet switch SPI) mainly not working.

Thanks



-- Fawad Lateef


On 3 April 2017 at 10:38, Fawad Lateef <[email protected]> wrote:
> Hi,
>
> I am facing some issues with device-trees (I am fairly new to them)
> and need some pointers about how to approach below problem:
>
> I got some I.MX6Q based hardware (some custom made whose hardware
> details are unknown to me). Hardware shipped with 3.10.53 kernel with
> full sources and everything is working on it
>
> Trying to get one of the recent kernel working on it (linux-4.4, from
> linux-linaro-stable with rt patches). I can compile the kernel and
> boot into it using 3.10.xx kernel compiled DTB but getting Warning at
> boot-time "Outdated DT detected, suspend/resume will NOT work" and few
> main hardware components not working (mainly ethernet(s) - 1 out of 4
> ports working though, MTD/NAND (for u-boot environment))
>
> So I looked into compiling the DTS (from 3.10 kernel) for 4.4 and
> managed to get it compiled. Now no warning of outdated DT _but_ still
> hardware components not working.
>
> I was assuming that as hardware is still same for both kernel 3.10 and
> 4.4, so it should work, but seems like something in DT is off for 4.4
> kernel.
>
> Any help and suggestions will be good enough for me to look into above issue.
>
> Thanks and regards,
>
> -- Fawad Lateef

2017-04-04 11:12:25

by Fawad Lateef

[permalink] [raw]
Subject: Re: Suggestions needed for resolving DT issues between kernel 3.10 and 4.4

Hi,

Just as an update (and for future reference for anyone having similar issue):

I got this all this sorted-out. Had to change some dt-binding for
device and it was mostly drivers related changes for hardware
components. Mostly nothing to do with DT.

Thanks

Fawad Lateef

-- Fawad Lateef


On 3 April 2017 at 10:54, Fawad Lateef <[email protected]> wrote:
> Hi,
>
> One more thing I realised that eth0 which is working is directly out
> of SOM/SOC but other 3 eth ports are connected to a internal USB
> switch (so Linux should see only eth1 besides eth0).
>
> So seems like flash/nand chip (m25p80) and spi_ks8995 (Micrel KS8995
> Ethernet switch SPI) mainly not working.
>
> Thanks
>
>
>
> -- Fawad Lateef
>
>
> On 3 April 2017 at 10:38, Fawad Lateef <[email protected]> wrote:
>> Hi,
>>
>> I am facing some issues with device-trees (I am fairly new to them)
>> and need some pointers about how to approach below problem:
>>
>> I got some I.MX6Q based hardware (some custom made whose hardware
>> details are unknown to me). Hardware shipped with 3.10.53 kernel with
>> full sources and everything is working on it
>>
>> Trying to get one of the recent kernel working on it (linux-4.4, from
>> linux-linaro-stable with rt patches). I can compile the kernel and
>> boot into it using 3.10.xx kernel compiled DTB but getting Warning at
>> boot-time "Outdated DT detected, suspend/resume will NOT work" and few
>> main hardware components not working (mainly ethernet(s) - 1 out of 4
>> ports working though, MTD/NAND (for u-boot environment))
>>
>> So I looked into compiling the DTS (from 3.10 kernel) for 4.4 and
>> managed to get it compiled. Now no warning of outdated DT _but_ still
>> hardware components not working.
>>
>> I was assuming that as hardware is still same for both kernel 3.10 and
>> 4.4, so it should work, but seems like something in DT is off for 4.4
>> kernel.
>>
>> Any help and suggestions will be good enough for me to look into above issue.
>>
>> Thanks and regards,
>>
>> -- Fawad Lateef