Re: [PATCH] clocksource/drivers/timer-mediatek: Split out CPUXGPT timers

[AngeloGioacchino Del Regno]

Il 29/03/23 09:51, Walter Chang (張維哲) ha scritto:
> On Thu, 2023-03-09 at 11:39 +0100, AngeloGioacchino Del Regno wrote:
> > On MediaTek platforms, CPUXGPT is the source for the AArch64 System
> > Timer, read through CNTVCT_EL0.
> >
> > The handling for starting this timer ASAP was introduced in commit
> > 327e93cf9a59 ("clocksource/drivers/timer-mediatek: Implement CPUXGPT
> > timers")
> > which description also contains an important full explanation of the
> > reasons why this driver is necessary and cannot be a module.
> >
> > In preparation for an eventual conversion of timer-mediatek to a
> > platform_driver that would be possibly built as a module, split out
> > the CPUXGPT timers driver to a new timer-mediatek-cpux.c driver.
> >
> > This commit brings no functional changes.
> >
> > Signed-off-by: AngeloGioacchino Del Regno <
> > angelogioacchino.delregno@xxxxxxxxxxxxx>
> > ---
> >
> > Note: I've added a mention to the commit that is introducing CPUXGPT
> > because it contains a broad explanation about why this is needed and
> > why it is mandatory to have it as built-in and initialized as early
> > as possible. This is mostly because this question was asked multiple
> > times and I've been pointing people to that commit to explain it all.
> >
> > This commit was made because of a discussion about the impossibility
> > to convert timer-mediatek to a module: even though that's definitely
> > not easy at all, this will make sure that whatever cannot (ever) be
> > built as module goes out of that driver.
> >
> > I tried to tackle a timer-mediatek conversion to platform_driver as
> > well, but I don't currently have the required bandwidth to do so:
> > as a first step I moved that, so I'm pushing this commit as to try
> > to reduce duplicated work.
> >
> > This commit was tested on MT6795 Sony Xperia M5.

..snip..

> > @@ -452,4 +339,3 @@ static int __init mtk_gpt_init(struct device_node
> > *node)
> >   }
> >   TIMER_OF_DECLARE(mtk_mt6577, "mediatek,mt6577-timer", mtk_gpt_init);
> >   TIMER_OF_DECLARE(mtk_mt6765, "mediatek,mt6765-timer",
> > mtk_syst_init);
> > -TIMER_OF_DECLARE(mtk_mt6795, "mediatek,mt6795-systimer",
> > mtk_cpux_init);
>
> This patch looks good to me. Thanks for assisting us in spliting out
> the CPUX driver.

Hello Walter,

thanks for checking this patch. If you have actually reviewed this one,
you could help the maintainers to know by releasing your Reviewed-by tag
on this patch.

Regards,
Angelo