From patchwork Wed Aug 29 15:56:18 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prarit Bhargava X-Patchwork-Id: 10580619 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 B8B99139B for ; Wed, 29 Aug 2018 15:56:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A4AC32ADCE for ; Wed, 29 Aug 2018 15:56:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 93DDA2B172; Wed, 29 Aug 2018 15:56:26 +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 D075F2ADCE for ; Wed, 29 Aug 2018 15:56:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728976AbeH2Tx7 (ORCPT ); Wed, 29 Aug 2018 15:53:59 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:60534 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728960AbeH2Tx7 (ORCPT ); Wed, 29 Aug 2018 15:53:59 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9649640216E8; Wed, 29 Aug 2018 15:56:23 +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 088E42026D6D; Wed, 29 Aug 2018 15:56:21 +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 v3] console: Add console=spcr option Date: Wed, 29 Aug 2018 11:56:18 -0400 Message-Id: <20180829155618.32359-1-prarit@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Wed, 29 Aug 2018 15:56:23 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Wed, 29 Aug 2018 15:56:23 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.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=spcr' that enables a firmware or hardware console, and on x86 enable the SPCR console if 'console=spcr' 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=spcr works (full console as expected) no console or earlycon arguments works (no output as expected) v2: Fix prototype. v3: Change parameter to "spcr" and add error message to spcr init call. 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 | 9 +++++++++ include/linux/console.h | 1 + kernel/printk/printk.c | 10 ++++++++++ 4 files changed, 21 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 9871e649ffef..f51a32cda90c 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. + spcr [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..3fed5e9a6b82 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -1771,3 +1771,12 @@ 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) +{ + int ret; + + ret = acpi_parse_spcr(false, true); + if (ret) + pr_err(PREFIX "ERROR: SPCR console is not enabled (%d)\n", ret); +} diff --git a/include/linux/console.h b/include/linux/console.h index ec9bdb3d7bab..562b825d911c 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -183,6 +183,7 @@ 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 *); +void 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 924e37fb1620..35859606e714 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2097,6 +2097,11 @@ static int __init console_msg_format_setup(char *str) } __setup("console_msg_format=", console_msg_format_setup); +void __init __weak arch_console_setup(void) +{ + return; +} + /* * Set up a console. Called via do_early_param() in init/main.c * for each "console=" parameter in the boot command line. @@ -2107,6 +2112,11 @@ static int __init console_setup(char *str) char *s, *options, *brl_options = NULL; int idx; + if (!strcmp(str, "spcr")) { + arch_console_setup(); + return 1; + } + if (_braille_console_setup(&str, &brl_options)) return 1;