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Message-ID: <cb4c5fd0-9629-4362-918a-cb044eb9e558@redhat.com>
Date: Thu, 30 May 2024 09:06:17 -0400
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Subject: Re: [PATCH] ACPI: Do not enable ACPI SPCR console by default on arm64
To: Liu Wei <liuwei09@cestc.cn>, catalin.marinas@arm.com, will@kernel.org
Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
 liuwei09.cestc.cn@cecloud.com
References: <20240530015332.7305-1-liuwei09@cestc.cn>
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From: Prarit Bhargava <prarit@redhat.com>
In-Reply-To: <20240530015332.7305-1-liuwei09@cestc.cn>
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On 5/29/24 21:53, Liu Wei wrote:
> Consistency with x86 and loongarch, don't enable ACPI SPCR console
> by default on arm64
> 
> Signed-off-by: Liu Wei <liuwei09@cestc.cn>
> ---
>   arch/arm64/kernel/acpi.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
> index dba8fcec7f33..1deda3e5a0d2 100644
> --- a/arch/arm64/kernel/acpi.c
> +++ b/arch/arm64/kernel/acpi.c
> @@ -227,7 +227,8 @@ void __init acpi_boot_table_init(void)
>   		if (earlycon_acpi_spcr_enable)
>   			early_init_dt_scan_chosen_stdout();
>   	} else {
> -		acpi_parse_spcr(earlycon_acpi_spcr_enable, true);
> +		/* Do not enable ACPI SPCR console by default */
> +		acpi_parse_spcr(earlycon_acpi_spcr_enable, false);
>   		if (IS_ENABLED(CONFIG_ACPI_BGRT))
>   			acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt);
>   	}

It's been a while, and the status of arm hardware may have changed. 
IIRC the choice to force enable this is that most arm hardware is 
headless and this was a _required_ option for booting.

I'm not sure if that's still the case as it's been a long time.

Can anyone from the ARM community provide an approval here?

P.