Re: [RFC PATCH-for-6.1 v2 6/6] hw/mips/loongson3_virt: Raise CPU clock to 2 GHz

From: Huacai Chen <chenhuacai@kernel.org>
To: "Philippe Mathieu-Daudé" <f4bug@amsat.org>
Cc: Peter Maydell <peter.maydell@linaro.org>,
	Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>,
	Luc Michel <luc@lmichel.fr>,
	QEMU Developers <qemu-devel@nongnu.org>,
	Hao Wu <wuhaotsh@google.com>,
	Aurelien Jarno <aurelien@aurel32.net>
Subject: Re: [RFC PATCH-for-6.1 v2 6/6] hw/mips/loongson3_virt: Raise CPU clock to 2 GHz
Date: Sat, 10 Apr 2021 10:43:52 +0800	[thread overview]
Message-ID: <CAAhV-H76XQZxvp9b2fE-R-Eq26GViaPR-iC2tG6PYhWtxNasxA@mail.gmail.com> (raw)
In-Reply-To: <20210409093623.2402750-7-f4bug@amsat.org>

Hi, Philippe,

On Fri, Apr 9, 2021 at 5:36 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> Commit cd3a53b727d ("clock: Add clock_ns_to_ticks() function")
> removed the limitation of using clock with a frequency of 1 GHz
> or more.
>
> The previous commit converted the MIPS CP0 timer to use this
> new clock_ns_to_ticks() function. We can now use a clock of
> 2 GHz with the Loongson3 virt board.
Yes, we can do this, but why should we do this? I don't think this can
bring any advantages.

Huacai
>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/mips/loongson3_virt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/hw/mips/loongson3_virt.c b/hw/mips/loongson3_virt.c
> index b15071defc6..0b72ef8a684 100644
> --- a/hw/mips/loongson3_virt.c
> +++ b/hw/mips/loongson3_virt.c
> @@ -152,7 +152,7 @@ static const MemoryRegionOps loongson3_pm_ops = {
>      }
>  };
>
> -#define DEF_LOONGSON3_FREQ (800 * 1000 * 1000)
> +#define DEF_LOONGSON3_FREQ (2000 * 1000 * 1000)
>
>  static uint64_t get_cpu_freq_hz(void)
>  {
> --
> 2.26.3
>