From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AC817C2BA18 for ; Tue, 18 Jun 2024 15:29:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xksveUIRSysdOvD9p2keX7CSAB7fvgaO307M76YIOc0=; b=yTykoZFrM7l39uj1qZaG07RQ/x WZOaIcSIxnVut7/73mIZ0VHBqOP1WPQr0LJroImH3Kk9Oa3RKsd9Ib9lLINaEJEC/+he0d62h2WiJ m1IEmRWzvdb4Aa8/1zmRiu+fNthmcx8ErN7dOv8CNdCyuLT3b8gxx0VL0FSu2cLd7F0EJU0CLp3dw lYManyNQnF5P+H6kFYxoOVvZdqB+3/np9EcUWyXVSQYmjumma9QJ1xXhM/C4aWT3X7VcqmxXFKC8Y 3d2wGbKTuoOfFT7NhbAo+KaFauKWOVm8K4CGHkdjp7lUzmFbbRr3Qu7hPoxl5adsjYgNh6VkqGkdB 0hdXd1+A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sJam6-0000000FcbO-400c; Tue, 18 Jun 2024 15:29:34 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sJam2-0000000Fcai-29Tm for linux-arm-kernel@lists.infradead.org; Tue, 18 Jun 2024 15:29:33 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 8D41C61A02; Tue, 18 Jun 2024 15:29:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 64A6FC3277B; Tue, 18 Jun 2024 15:29:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718724569; bh=TG21y/qDqCjS/KRsSTEig3GJf7UCaKAZ3Qv9HtDwB50=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cPJgA2o1NK9yDTJXz0NUaQDmJBzUQL9HjmgWpihepZnBwCm7J0cme55QC8TZHc+Ey ogui/l8cYvnBL/E20T9ZBtVNauA3UPIwZlUNliK92kZxhYAn+VRFwwJgjkK1Z4Aa6Z 9bgmSvR/0MopKoXyCGfdqrKfBlpgrZTBbMgA8VtfFGLb5pRS+6CslR0LpYVinCctYL ppyWQYD4IlD3IUenVTuDmCtjaB7ZJS4acC2PKuH7OPz3PrKxEHDNUE9IVj4rpGyGJO 7pK3t2A949RjZEnvpXgF219Jn2Kp0v9pXnrkYqLzjHu4aV5VmXQW79THoEyH45ftTs IwzMaoON7tpRQ== Date: Tue, 18 Jun 2024 16:29:24 +0100 From: Will Deacon To: Prarit Bhargava , sudeep.holla@arm.com, lpieralisi@kernel.org, guohanjun@huawei.com Cc: Liu Wei , catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, liuwei09.cestc.cn@cecloud.com, rafael@kernel.org Subject: Re: [PATCH] ACPI: Do not enable ACPI SPCR console by default on arm64 Message-ID: <20240618152923.GB2354@willie-the-truck> References: <20240530015332.7305-1-liuwei09@cestc.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240618_082932_809087_B2CF5703 X-CRM114-Status: GOOD ( 23.81 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, May 30, 2024 at 09:06:17AM -0400, Prarit Bhargava wrote: > 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 > > --- > > 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? I don't have a strong opinion either way, but adding the Arm ACPI folks in case they care. Having said that, if the only rationale for this patch is consistency with other architectures, then I think I'd lean towards leaving the behaviour as-is so we don't give users a nasty surprise on their next kernel upgrade. Will