From patchwork Thu Aug 16 14:10:55 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prarit Bhargava X-Patchwork-Id: 10567561 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5317A139A for ; Thu, 16 Aug 2018 14:11:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 39ECF2B38E for ; Thu, 16 Aug 2018 14:11:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 381552B3AF; Thu, 16 Aug 2018 14:11:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4B97F2B38E for ; Thu, 16 Aug 2018 14:11:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390948AbeHPRKI (ORCPT ); Thu, 16 Aug 2018 13:10:08 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:53626 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2390887AbeHPRKI (ORCPT ); Thu, 16 Aug 2018 13:10:08 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 436214023351; Thu, 16 Aug 2018 14:11:14 +0000 (UTC) Received: from prarit.bos.redhat.com (prarit-guest.khw.lab.eng.bos.redhat.com [10.16.186.145]) by smtp.corp.redhat.com (Postfix) with ESMTP id 533132166BA0; Thu, 16 Aug 2018 14:11:11 +0000 (UTC) From: Prarit Bhargava To: linux-kernel@vger.kernel.org Cc: Prarit Bhargava , Mark Salter , Al Stone , "Rafael J. Wysocki" , Len Brown , Pavel Machek , x86@kernel.org, Petr Mladek , Sergey Senozhatsky , Steven Rostedt , Kees Cook , Greg Kroah-Hartman , linux-pm@vger.kernel.org Subject: [PATCH] console: Add console=auto option Date: Thu, 16 Aug 2018 10:10:55 -0400 Message-Id: <20180816141055.451-1-prarit@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Thu, 16 Aug 2018 14:11:14 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Thu, 16 Aug 2018 14:11:14 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'prarit@redhat.com' RCPT:'' Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP ACPI may contain an SPCR table that defines a default system console. On ARM if the table is present then the SPCR console is enabled by default. On x86 the SPCR console is used if 'earlycon' (no parameters) is specified as a kernel parameter and is used only as the early console. To use the SPCR data as a console a user must boot with 'earlycon', grep logs & specify a console= kernel parameter, and then reboot again. Add 'console=auto' that enables a firmware or hardware console, and on x86 enable the SPCR console if 'console=auto' is specified. Tested on systems with and without an ACPI SPCR. The following kernel parameters were also tested: console=ttyS0,115200 works earlycon works (early console only) console=auto works (full console as expected) no console or earlycon arguments works (no output as expected) Signed-off-by: Prarit Bhargava Cc: Mark Salter Cc: Al Stone Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Pavel Machek Cc: x86@kernel.org Cc: Petr Mladek Cc: Sergey Senozhatsky Cc: Steven Rostedt Cc: Kees Cook Cc: Greg Kroah-Hartman Cc: linux-pm@vger.kernel.org --- Documentation/admin-guide/kernel-parameters.txt | 1 + arch/x86/kernel/acpi/boot.c | 5 +++++ include/linux/console.h | 1 + kernel/printk/printk.c | 10 ++++++++++ 4 files changed, 17 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a32f2a126791..dd057224f33b 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -635,6 +635,7 @@ hvc Use the hypervisor console device . This is for both Xen and PowerPC hypervisors. + auto [X86] Enable ACPI SPCR console If the device connected to the port is not a TTY but a braille device, prepend "brl," before the device type, for instance diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 3b20607d581b..fb2616ba3b21 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -1771,3 +1771,8 @@ void __init arch_reserve_mem_area(acpi_physical_address addr, size_t size) e820__range_add(addr, size, E820_TYPE_ACPI); e820__update_table_print(); } + +void __init arch_console_setup(void) +{ + acpi_parse_spcr(false, true); +} diff --git a/include/linux/console.h b/include/linux/console.h index dfd6b0e97855..b802f62289a9 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -181,6 +181,7 @@ extern int is_console_locked(void); extern int braille_register_console(struct console *, int index, char *console_options, char *braille_options); extern int braille_unregister_console(struct console *); +int arch_console_setup(void); #ifdef CONFIG_TTY extern void console_sysfs_notify(void); #else diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 247808333ba4..b74eba44183e 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2078,6 +2078,11 @@ static int __init console_msg_format_setup(char *str) } __setup("console_msg_format=", console_msg_format_setup); +int __init __weak arch_console_setup(void) +{ + return 0; +} + /* * Set up a console. Called via do_early_param() in init/main.c * for each "console=" parameter in the boot command line. @@ -2088,6 +2093,11 @@ static int __init console_setup(char *str) char *s, *options, *brl_options = NULL; int idx; + if (!strcmp(str, "auto")) { + arch_console_setup(); + return 1; + } + if (_braille_console_setup(&str, &brl_options)) return 1;