Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754607Ab0AURU5 (ORCPT ); Thu, 21 Jan 2010 12:20:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752929Ab0AURUo (ORCPT ); Thu, 21 Jan 2010 12:20:44 -0500 Received: from percival.namespace.at ([77.244.242.130]:52025 "EHLO percival.namespace.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752737Ab0AURUn (ORCPT ); Thu, 21 Jan 2010 12:20:43 -0500 From: Christian Hofstaedtler To: x86@kernel.org Cc: hpa@zytor.com, lenb@kernel.org, tglx@linutronix.de, linux-acpi@vger.kernel.org, venkatesh.pallipadi@intel.com, arjan@infradead.org, bruce.w.allan@intel.com, linux-kernel@vger.kernel.org, Christian Hofstaedtler Subject: [PATCH 2/2] Default to ACPI reboots on newish X86 hardware Date: Thu, 21 Jan 2010 18:18:43 +0100 Message-Id: <1264094323-7187-2-git-send-email-ch@zeha.at> X-Mailer: git-send-email 1.6.4.4 In-Reply-To: <1264094323-7187-1-git-send-email-ch@zeha.at> References: <1264094323-7187-1-git-send-email-ch@zeha.at> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2212 Lines: 73 Newer hardware reportedly can no longer successfully reboot using the keyboard controller, but needs to use ACPI instead. To not cause problems with older hardware, only hardware with a BIOS date 2003 or newer is considered for this choice. Broken BIOSes (no DMI BIOS date, or BIOS date of 0) also get ACPI reboots, but those will auto fallback to KBD reboots, as ACPI won't get enabled without acpi=force. --- arch/x86/kernel/reboot.c | 32 ++++++++++++++++++++++++++++++-- 1 files changed, 30 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 36f0c86..919453a 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -453,10 +453,33 @@ static struct dmi_system_id __initdata reboot_dmi_table_all[] = { { } }; +/* See if the Hardware is new enough to support ACPI reboots. */ +static int __init reboot_acpi_likey_supported(void) +{ + int year; + + /* No BIOS date? We can safely say "Yes" here, because ACPI-reboot + * will only work when acpi=force was specified, else it falls back + * to KBD-reboots anyway. */ + if (!dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL)) { + return 1; + } + if (year == 0) { + return 1; + } + + /* 2003 was decided as the cut-off year. */ + if (year < 2003) { + return 0; + } + return 1; +} + /* Decide how we will reboot: * - Check the X86_32-only quirks table. * - Check the generic quirks table. - * - Default to old-style Keyboard Controller reboot. + * - Check if we could use ACPI-based reboot. + * - Fall back to old-style Keyboard Controller reboot. */ static int __init reboot_init(void) { @@ -472,7 +495,12 @@ static int __init reboot_init(void) if (reboot_type != BOOT_UNDECIDED) return 0; - reboot_type = BOOT_KBD; + if (reboot_acpi_likey_supported()) { + reboot_type = BOOT_ACPI; + } else { + printk(KERN_INFO "Selecting old-style reboot for older hardware\n"); + reboot_type = BOOT_KBD; + } return 0; } -- 1.6.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/