[PATCH] arm: dts: imx8mp: Delete default clocks for clock controller node

[Stefano Babic]

Hi Peng,

On 15.09.21 05:01, Peng Fan (OSS) wrote:
> 
> 
> On 2021/8/17 14:32, Ye Li wrote:
>> Since SPL has initialized clocks for bus and core. We don't need to
>> set the default clocks for clock controller node.
>>
>> Signed-off-by: Ye Li <ye.li at nxp.com>
>> ---
>>   arch/arm/dts/imx8mp-u-boot.dtsi | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/arch/arm/dts/imx8mp-u-boot.dtsi 
>> b/arch/arm/dts/imx8mp-u-boot.dtsi
>> index d61346d..a6ede2e 100644
>> --- a/arch/arm/dts/imx8mp-u-boot.dtsi
>> +++ b/arch/arm/dts/imx8mp-u-boot.dtsi
>> @@ -18,6 +18,9 @@
>>   &clk {
>>       u-boot,dm-spl;
>>       u-boot,dm-pre-reloc;
>> +    /delete-property/ assigned-clocks;
>> +    /delete-property/ assigned-clock-parents;
>> +    /delete-property/ assigned-clock-rates;
>>   };
>>   &osc_32k {
>>
> 
> For a release fix, this is ok.
> Acked-by: Peng Fan <peng.fan at nxp.com>
> 
> But for distro boot, we need think Linux Kernel will
> use the device tree exported by U-Boot. Removing
> this property may cause issue.
> 

But let's think this is not the only use case. The other use case is 
kernel has its own DT and not the one from U-Boot. In products in field, 
if kernel has a strong dependency from U-Boot, a kernel update can be 
done only if it is together a bootloader update.

> I think other vendors may has similar issue
> that U-Boot modify dtb and corrupt distribution
> kernel booting.

We should also think about if thsi is a good thing. There could not be a 
kernel update without a u-boot update. And just a few devices have 
support for a powercut safe bootloader update.

I do not want to be very OT, I apply the patch, sorry for delay.

Best regards,
Stefano Babic



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