ACPI: Disable MWAIT via DMI on broken Compal board
If a system matches in this DMI table,
Linux will disable MWAIT support for idle.
ie. "idle=nomwait" is automatically invoked
and C1_FFH and C2C3_FFH access mode are disabled.
http://bugzilla.kernel.org/show_bug.cgi?id=10807
http://bugzilla.kernel.org/show_bug.cgi?id=10914
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 4e1bb89..ec0f2d5 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -120,6 +120,29 @@
DEFINE_PER_CPU(struct acpi_processor *, processors);
struct acpi_processor_errata errata __read_mostly;
+static int set_no_mwait(const struct dmi_system_id *id)
+{
+ printk(KERN_NOTICE PREFIX "%s detected - "
+ "disable mwait for CPU C-stetes\n", id->ident);
+ idle_nomwait = 1;
+ return 0;
+}
+
+static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = {
+ {
+ set_no_mwait, "IFL91 board", {
+ DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
+ DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"),
+ DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"),
+ DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL},
+ {
+ set_no_mwait, "Extensa 5220", {
+ DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
+ DMI_MATCH(DMI_SYS_VENDOR, "ACER"),
+ DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
+ DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
+ {},
+};
/* --------------------------------------------------------------------------
Errata Handling
@@ -1100,6 +1123,11 @@
return -ENOMEM;
acpi_processor_dir->owner = THIS_MODULE;
+ /*
+ * Check whether the system is DMI table. If yes, OSPM
+ * should not use mwait for CPU-states.
+ */
+ dmi_check_system(processor_idle_dmi_table);
result = cpuidle_register_driver(&acpi_idle_driver);
if (result < 0)
goto out_proc;
