[PATCH v2 1/9] dt-bindings: imx6q-pcie: Add ref clock for i.MX95 PCIe
Krzysztof Kozlowski
krzk at kernel.org
Wed Sep 25 12:28:25 PDT 2024
On 25/09/2024 18:46, Frank Li wrote:
> On Wed, Sep 25, 2024 at 09:50:06AM +0200, Krzysztof Kozlowski wrote:
>> On Wed, Sep 25, 2024 at 02:24:29PM +0800, Richard Zhu wrote:
>>> Previous reference clock of i.MX95 is on when system boot to kernel. But
>>> boot firmware change the behavor, it is off when boot. So it needs be turn
>>> on when it is used. Also it needs be turn off/on when suspend and resume.
>>
>> That's an old platform... How come that you changed bootloader just now?
>> Like 7 or 8 years after?
>
> It is new platform, which just publish in this year. Old platform reference
> clock was controlled in PCI module, so needn't export to DT. So we have
> not realized it when start i.MX95 work.
Indeed, I missed that it is i.MX95, not i.MX6q.
>
>>
>> For the future: you should document all clock inputs, not only ones
>> needed for given bootloader...
>
> Understand.
Sorry, in case of early upstreaming it's understandable.
>
>>
>>>
>>> Add one ref clock for i.MX95 PCIe. Increase clocks' maxItems to 5 and keep
>>> the same restriction with other compatible string.
>>
>> <form letter>
>> Please use scripts/get_maintainers.pl to get a list of necessary people
>> and lists to CC (and consider --no-git-fallback argument). It might
>> happen, that command when run on an older kernel, gives you outdated
>> entries. Therefore please be sure you base your patches on recent Linux
>> kernel.
>>
>> Tools like b4 or scripts/get_maintainer.pl provide you proper list of
>> people, so fix your workflow. Tools might also fail if you work on some
>> ancient tree (don't, instead use mainline) or work on fork of kernel
>> (don't, instead use mainline). Just use b4 and everything should be
>> fine, although remember about if you added new
>> patches to the patchset.
>> </form letter>
>>
>> and I was wondering why I cannot find this and previous thread in my
>> inbox... So please stop developing on two year old kernels (and before
>> you say "I do not", well, then fix way how you use tools).
>>
>>
>>>
>>> Signed-off-by: Richard Zhu <hongxing.zhu at nxp.com>
>>> ---
>>> .../bindings/pci/fsl,imx6q-pcie-common.yaml | 4 +--
>>> .../bindings/pci/fsl,imx6q-pcie.yaml | 25 ++++++++++++++++---
>>> 2 files changed, 23 insertions(+), 6 deletions(-)
>>>
>>
>> You missed to update ep binding.
>
> So far, EP don't need reference clock. PCIe standard require host provide
> 100MHz reference clock to EP side. But EP side can choose use itself's
> clock or reference clock from PCIe bus. Currently i.MX95 only support clock
> from internal PLL when work as EP mode.
But this patch allowed certain existing variants in EP to have 5 clocks.
You missed to update EP binding...
Best regards,
Krzysztof
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