[PATCH v5 04/10] coresight: Appropriately disable programming clocks

Leo Yan leo.yan at arm.com
Wed Jul 30 10:57:36 PDT 2025


On Wed, Jul 30, 2025 at 12:09:42PM +0100, Mark Brown wrote:
> On Wed, Jul 30, 2025 at 12:01:25PM +0100, Suzuki K Poulose wrote:
> 
> > I would recommend using that and don't force the use of apb_clk/apb
> > for AMBA devices. If the firmware doesn't specify a clock, but does
> > specify the CoreSight components, it knows it better.
> 
> And perhaps more to the point if a currently working system suddenly
> starts requiring additional clocks in it's binding that's an ABI break.

Yes, the change should not break any platforms if the DT binding is
passed correctly. I will update with devm_clk_get_optional_enabled().

Just for the record, I was a bit concerned that the driver might not
report a missing clock after switching to the optional clock API.
After discussed with Rob and Suzuki, I understand this should not be a
problem. Any missing clock issue can be caught by the DT schema static
checker, or a system hang during the development phase would remind
developers to bind clocks properly.

Thanks,
Leo



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