[PATCH] x86/reboot: Add Dell Optiplex 7450 AIO reboot quirk

[Alex Hung]

Dell Optiplex 7450 AIO works with BOOT_ACPI; however, the quirk for
"OptiPlex 745" changes its boot method to BOOT_BIOS and causes 7450 AIO
hangs when rebooting; as a result, 7450 AIO is appended to overwrite
BOOT_BIOS by BOOT_ACPI in order not to break the original 745 series

Signed-off-by: Alex Hung <alex.hung at canonical.com>
Cc: Linus Torvalds <torvalds at linux-foundation.org>
Cc: Peter Zijlstra <peterz at infradead.org>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: linux-kernel at vger.kernel.org
Signed-off-by: Ingo Molnar <mingo at kernel.org>
(cherry picked from commit 4d581259b7d44c8120a614b4e9244094c824d51f)
Signed-off-by: Alex Hung <alex.hung at canonical.com>
---
 arch/x86/kernel/reboot.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index b7e1d5f..b404d05 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -55,6 +55,19 @@ bool port_cf9_safe = false;
  */
 
 /*
+ * Some machines require the "reboot=a" commandline options
+ */
+static int __init set_acpi_reboot(const struct dmi_system_id *d)
+{
+	if (reboot_type != BOOT_ACPI) {
+		reboot_type = BOOT_ACPI;
+		pr_info("%s series board detected. Selecting %s-method for reboots.\n",
+			d->ident, "ACPI");
+	}
+	return 0;
+}
+
+/*
  * Some machines require the "reboot=b" or "reboot=k"  commandline options,
  * this quirk makes that automatic.
  */
@@ -395,6 +408,14 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 		},
 	},
+	{	/* Handle problems with rebooting on Dell Optiplex 7450 AIO */
+		.callback = set_acpi_reboot,
+		.ident = "Dell OptiPlex 7450 AIO",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7450 AIO"),
+		},
+	},
 
 	/* Hewlett-Packard */
 	{	/* Handle problems with rebooting on HP laptops */
-- 
2.7.4