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SubjectRe: [PATCH] cpufreq: cpufreq-cpu0: Use a sane boot frequency when booting with a mismatched bootloader configuration
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On 16 November 2013 19:14, Shawn Guo <shawn.guo@linaro.org> wrote:
> No, it's not a kernel bug.
>
> OPP is not a definition that belongs to kernel. Instead, it's
> characteristics of hardware, and that's why we can naturally put the
> definition into device tree. Bear it in mind that device tree is a
> hardware description and should be OS agnostic. So it shouldn't be
> treated as part of Linux kernel in any case, even though the device
> tree source is currently maintained in kernel tree.
>
> Device tree is designed as a way for firmware/bootloader to describe
> hardware to kernel. That said, device tree is more part of bootloader
> than kernel. If bootloader runs at a frequency that does not match the
> OPP in device tree, the one should be fixed is either bootloader or
> device tree but never kernel.

I agree for all that..

> However, I agree we should at least have a check in cpufreq-cpu0 driver
> and fail out in case that a mismatch is detected.

But not here.. We aren't in a non-workable state here.. and so creating
panic isn't the right approach.

At max we can print an warning but then it doesn't lie in cpufreq-cpu0's
domain. It should be done in core if required..

Though for Shawn's information we have another thread in parallel for
this issue. You might like to check that too..

https://lkml.org/lkml/2013/11/15/503


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