[PATCH] clocksource/drivers/exynos_mct: Use percpu interrupts only on ARM64

[Marek Szyprowski]

Hi Daniel,

On 24.09.2025 10:41, Daniel Lezcano wrote:
>
> On 19/09/2025 23:31, Marek Szyprowski wrote:
>> On 27.08.2025 13:58, Krzysztof Kozlowski wrote:
>>> On 27/08/2025 12:26, Marek Szyprowski wrote:
>>>> For some unknown reasons forcing percpu interrupts for local timers
>>>> breaks CPU hotplug for 'little' cores on legacy ARM 32bit Exynos based
>>>> machines (for example Exynos5422-based Odroid-XU3/XU4 boards). Use 
>>>> percpu
>>>> flag only when driver is compiled for newer ARM64 architecture.
>>>>
>>>> Fixes: f3cec54ee3bf ("clocksource/drivers/exynos_mct: Set local 
>>>> timer interrupts as percpu")
>>>
>>> I am pretty sure the patch above was not tested on arm32, thus this
>>> workaround seems reasonable.
>>>
>>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski at linaro.org>
>>
>> Daniel, any chance to get this merged?
>
> The patch does not apply. However it is not your fault but a glitch in 
> the previous pull request and the regression found in the Exynos MCT.
>
> Apparently, Thomas had to drop the entire pull request while I thought 
> he dropped only Will's changes.
>
> A pull request with the previous changes for v6.17-rc1 and with the 
> new changes for v6.18-rc1 is about to be emitted but without the 
> Exynos MCT changes for the modularization. That means your change does 
> not apply correctly anymore on the current changes.

Thanks for the information. I've checked and 
https://git.kernel.org/pub/scm/linux/kernel/git/daniel.lezcano/linux.git/commit/?h=timers/drivers/next 
branch indeed doesn't contain the whole Exynos MCT modularization 
patchset, so the $subject patch (which was supposed to fix it) is not 
really needed.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland