tegra-devfreq hangs TK1 with R21.4 u-boot

tegra-devfreq hangs TK1 with R21.4 u-boot

[Martin Michlmayr]

I noticed that the Jetson TK1 hangs during boot (when/before mounting
the SD disk) when CONFIG_ARM_TEGRA_DEVFREQ=y is set and when u-boot
from R21.4 is used (2014.10-rc2).

The hang does not occur when I disable tegra-devfreq or when I use
tegra-devfreq in combination with u-boot 2016.03 (from DENX upstream,
built by Debian).

Steps to reproduce:

ARCH=arm make multi_v7_defconfig
Set CONFIG_ARM_TEGRA_DEVFREQ=y
Boot from an external SD card and it will hang when/before mounting the
SD card.

-- 
Martin Michlmayr
http://www.cyrius.com/

Re: tegra-devfreq hangs TK1 with R21.4 u-boot

[Shreshtha]

Martin Michlmayr <tbm@...> writes:

> 
> I noticed that the Jetson TK1 hangs during boot (when/before mounting
> the SD disk) when CONFIG_ARM_TEGRA_DEVFREQ=y is set and when u-boot
> from R21.4 is used (2014.10-rc2).

I cannot find CONFIG_ARM_TEGRA_DEVFREQ in r21.4 codeline. With default
"tegra12_defconfig", CONFIG_PM_DEVFREQ is getting enabled.

Can you please share some more details about CONFIG_ARM_TEGRA_DEVFREQ, which
file it complies and if it is really present in code or pulled from other git.

Re: tegra-devfreq hangs TK1 with R21.4 u-boot

[Martin Michlmayr]

* Shreshtha <shreshthakumar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> [2016-06-12 17:15]:
> > I noticed that the Jetson TK1 hangs during boot (when/before mounting
> > the SD disk) when CONFIG_ARM_TEGRA_DEVFREQ=y is set and when u-boot
> > from R21.4 is used (2014.10-rc2).
> 
> I cannot find CONFIG_ARM_TEGRA_DEVFREQ in r21.4 codeline. With default
> "tegra12_defconfig", CONFIG_PM_DEVFREQ is getting enabled.
> 
> Can you please share some more details about CONFIG_ARM_TEGRA_DEVFREQ, which
> file it complies and if it is really present in code or pulled from other git.

Sorry for not being clear.  I'm talking about the mainline kernel from
kernel.org:
drivers/devfreq/Makefile:obj-$(CONFIG_ARM_TEGRA_DEVFREQ)                += tegra-devfreq.o

Booting a mainline kernel with tegra-devfreq enabled will hang my machine
during bootup when I use the u-boot from R21.4 (which I believe is the
latest provided by NVIDIA).

-- 
Martin Michlmayr
http://www.cyrius.com/

Re: tegra-devfreq hangs TK1 with R21.4 u-boot

[Tomeu Vizoso]

On 12 June 2016 at 05:45, Martin Michlmayr <tbm-R+vWnYXSFMfQT0dZR+AlfA@public.gmane.org> wrote:
> I noticed that the Jetson TK1 hangs during boot (when/before mounting
> the SD disk) when CONFIG_ARM_TEGRA_DEVFREQ=y is set and when u-boot
> from R21.4 is used (2014.10-rc2).
>
> The hang does not occur when I disable tegra-devfreq or when I use
> tegra-devfreq in combination with u-boot 2016.03 (from DENX upstream,
> built by Debian).

Works as well with 2015.01, which is closer to the one in R21.4.

https://lava.collabora.co.uk/scheduler/job/238991/log_file#L_3_5

Regards,

Tomeu

> Steps to reproduce:
>
> ARCH=arm make multi_v7_defconfig
> Set CONFIG_ARM_TEGRA_DEVFREQ=y
> Boot from an external SD card and it will hang when/before mounting the
> SD card.
>
> --
> Martin Michlmayr
> http://www.cyrius.com/
> --
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Re: tegra-devfreq hangs TK1 with R21.4 u-boot

[Thierry Reding]

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On Sat, Jun 11, 2016 at 08:45:41PM -0700, Martin Michlmayr wrote:
> I noticed that the Jetson TK1 hangs during boot (when/before mounting
> the SD disk) when CONFIG_ARM_TEGRA_DEVFREQ=y is set and when u-boot
> from R21.4 is used (2014.10-rc2).
> 
> The hang does not occur when I disable tegra-devfreq or when I use
> tegra-devfreq in combination with u-boot 2016.03 (from DENX upstream,
> built by Debian).
> 
> Steps to reproduce:
> 
> ARCH=arm make multi_v7_defconfig
> Set CONFIG_ARM_TEGRA_DEVFREQ=y
> Boot from an external SD card and it will hang when/before mounting the
> SD card.

Stephen, any ideas what might be going on here?

Thierry

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Re: tegra-devfreq hangs TK1 with R21.4 u-boot

[Stephen Warren]

On 06/12/2016 11:31 AM, Martin Michlmayr wrote:
> * Shreshtha <shreshthakumar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> [2016-06-12 17:15]:
>>> I noticed that the Jetson TK1 hangs during boot (when/before mounting
>>> the SD disk) when CONFIG_ARM_TEGRA_DEVFREQ=y is set and when u-boot
>>> from R21.4 is used (2014.10-rc2).
>>
>> I cannot find CONFIG_ARM_TEGRA_DEVFREQ in r21.4 codeline. With default
>> "tegra12_defconfig", CONFIG_PM_DEVFREQ is getting enabled.
>>
>> Can you please share some more details about CONFIG_ARM_TEGRA_DEVFREQ, which
>> file it complies and if it is really present in code or pulled from other git.
>
> Sorry for not being clear.  I'm talking about the mainline kernel from
> kernel.org:
> drivers/devfreq/Makefile:obj-$(CONFIG_ARM_TEGRA_DEVFREQ)                += tegra-devfreq.o
>
> Booting a mainline kernel with tegra-devfreq enabled will hang my machine
> during bootup when I use the u-boot from R21.4 (which I believe is the
> latest provided by NVIDIA).

Note that if you're booting a mainline kernel, there's no need to use 
the L4T U-Boot release; a mainline U-Boot release should work just fine. 
Or put another way, the "latest provided by NVIDIA" is actually mainline 
U-Boot, unless you need to boot a downstream L4T kernel which has some 
downstream-specific requirements.

Re: tegra-devfreq hangs TK1 with R21.4 u-boot

[Stephen Warren]

On 06/16/2016 10:16 AM, Thierry Reding wrote:
> On Sat, Jun 11, 2016 at 08:45:41PM -0700, Martin Michlmayr wrote:
>> I noticed that the Jetson TK1 hangs during boot (when/before mounting
>> the SD disk) when CONFIG_ARM_TEGRA_DEVFREQ=y is set and when u-boot
>> from R21.4 is used (2014.10-rc2).
>>
>> The hang does not occur when I disable tegra-devfreq or when I use
>> tegra-devfreq in combination with u-boot 2016.03 (from DENX upstream,
>> built by Debian).
>>
>> Steps to reproduce:
>>
>> ARCH=arm make multi_v7_defconfig
>> Set CONFIG_ARM_TEGRA_DEVFREQ=y
>> Boot from an external SD card and it will hang when/before mounting the
>> SD card.
>
> Stephen, any ideas what might be going on here?

I can't think of anything obvious, and the commit history of the L4T 
U-Boot is constructed in such a way that's it's essentially impossible 
to follow, so I can't easily tell what changes exist in the L4T U-Boot 
release that weren't upstream or vice-versa. If simply using mainline 
U-Boot works and is an option for you, I'd suggest that.

Re: tegra-devfreq hangs TK1 with R21.4 u-boot

[Martin Michlmayr]

* Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> [2016-06-17 10:30]:
> If simply using mainline U-Boot works and is an option for you, I'd
> suggest that.

Sure, that works for me.

Some background: I'm currently in the process of documenting how to
run Debian on the TK1.  I wanted to give users a choice to stay with
the u-boot from R21.4 or to upgrade to a newer mainline u-boot.  And
then I ran into the problems with the R21.4 u-boot I described.

I'm perfectly fine with telling users they have to upgrade to mainline
u-boot.  We provide precompiled u-boot binaries for TK1 in Debian
anyway.

-- 
Martin Michlmayr
http://www.cyrius.com/