Re: [PATCH] arm64: Kconfig: Enable MCT timer for ARCH_EXYNOS

From: Marek Szyprowski <m.szyprowski@samsung.com>
To: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
	Sam Protsenko <semen.protsenko@linaro.org>
Cc: linux-arm Mailing List <linux-arm-kernel@lists.infradead.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux Samsung SOC <linux-samsung-soc@vger.kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Chanwoo Choi <cw00.choi@samsung.com>,
	Will Deacon <will@kernel.org>,
	Marc Zyngier <marc.zyngier@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>
Subject: Re: [PATCH] arm64: Kconfig: Enable MCT timer for ARCH_EXYNOS
Date: Fri, 29 Oct 2021 13:38:55 +0200	[thread overview]
Message-ID: <d4398079-e512-e75b-92e9-51d590d8c240@samsung.com> (raw)
In-Reply-To: <e01b0072-008a-c83d-59b2-2174860c00fd@canonical.com>

On 28.10.2021 16:35, Krzysztof Kozlowski wrote:
> On 28/10/2021 16:22, Sam Protsenko wrote:
>> On Tue, 26 Oct 2021 at 17:03, Krzysztof Kozlowski
>> <krzysztof.kozlowski@canonical.com> wrote:
>>> On 26/10/2021 13:59, Sam Protsenko wrote:
>>>> Some ARM64 Exynos SoCs have MCT timer block, e.g. Exynos850 and
>>>> Exynos5433. CLKSRC_EXYNOS_MCT option is not visible unless COMPILE_TEST
>>>> is enabled. Select CLKSRC_EXYNOS_MCT option for ARM64 ARCH_EXYNOS like
>>>> it's done in arch/arm/mach-exynos/Kconfig, to enable MCT timer support
>>>> for ARM64 Exynos SoCs.
>>>>
>>>> Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
>>>> ---
>>>>   arch/arm64/Kconfig.platforms | 1 +
>>>>   1 file changed, 1 insertion(+)
>>>>
>>> +CC Marek, Marc, Mark and Chanwoo,
>>> Looks like duplicated:
>>> https://lore.kernel.org/lkml/20181018095708.1527-7-m.szyprowski@samsung.com/
>>>
>>> The topic stalled and I think this particular patch did not make sense
>>> on its own, without rest of changes from Marek. I am not sure, though...
>>>
>> Krzysztof, Marek,
>>
>> That series looks nice, I'm quite interested in that being applied. Do
>> you think I can do something to help with that (e.g. rebasing,
>> re-sending on behalf of Marek, testing on Exynos850, etc)?
> I think there were no objections against v4 of this patchset, but
> somehow it wasn't applied.
>
> Marek,
> Does it make sense to try respinning your v4?

I think I've abandoned it, because I got a final NACK on the arch timer 
change (support for 'not-fw-configured' timers). Without that the above 
mentioned changes doesn't make much sense.

I know that the Exynos5433 firmware breaks the defined protocol, but on 
the other hand I can do nothing more than carrying internally those few 
patches out of tree to keep it fully working with 'mainline'.

I've observed the same problem with newer Exynos SoCs, but those so far 
didn't get mainline support (yet), although there have been some 
attempts from the community.

Best regards

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