[ACPI] enable C2 and C3 idle power states on SMP

http://bugzilla.kernel.org/show_bug.cgi?id=4401

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 107 insertions, 0 deletions

diff --git a/arch/i386/kernel/acpi/Makefile b/arch/i386/kernel/acpi/Makefile
index ee75cb286cf..5e291a20c03 100644
--- a/arch/i386/kernel/acpi/Makefile
+++ b/arch/i386/kernel/acpi/Makefile
@@ -2,3 +2,7 @@ obj-$(CONFIG_ACPI_BOOT)		:= boot.o
 obj-$(CONFIG_X86_IO_APIC)	+= earlyquirk.o
 obj-$(CONFIG_ACPI_SLEEP)	+= sleep.o wakeup.o
 
+ifneq ($(CONFIG_ACPI_PROCESSOR),)
+obj-y				+= cstate.o
+endif
+
diff --git a/arch/i386/kernel/acpi/cstate.c b/arch/i386/kernel/acpi/cstate.c
new file mode 100644
index 00000000000..4c3036ba65d
--- /dev/null
+++ b/arch/i386/kernel/acpi/cstate.c
@@ -0,0 +1,103 @@
+/*
+ * arch/i386/kernel/acpi/cstate.c
+ *
+ * Copyright (C) 2005 Intel Corporation
+ * 	Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
+ * 	- Added _PDC for SMP C-states on Intel CPUs
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+
+#include <acpi/processor.h>
+#include <asm/acpi.h>
+
+static void acpi_processor_power_init_intel_pdc(struct acpi_processor_power
+						*pow)
+{
+	struct acpi_object_list *obj_list;
+	union acpi_object *obj;
+	u32 *buf;
+
+	/* allocate and initialize pdc. It will be used later. */
+	obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
+	if (!obj_list) {
+		printk(KERN_ERR "Memory allocation error\n");
+		return;
+	}
+
+	obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
+	if (!obj) {
+		printk(KERN_ERR "Memory allocation error\n");
+		kfree(obj_list);
+		return;
+	}
+
+	buf = kmalloc(12, GFP_KERNEL);
+	if (!buf) {
+		printk(KERN_ERR "Memory allocation error\n");
+		kfree(obj);
+		kfree(obj_list);
+		return;
+	}
+
+	buf[0] = ACPI_PDC_REVISION_ID;
+	buf[1] = 1;
+	buf[2] = ACPI_PDC_C_CAPABILITY_SMP;
+
+	obj->type = ACPI_TYPE_BUFFER;
+	obj->buffer.length = 12;
+	obj->buffer.pointer = (u8 *) buf;
+	obj_list->count = 1;
+	obj_list->pointer = obj;
+	pow->pdc = obj_list;
+
+	return;
+}
+
+/* Initialize _PDC data based on the CPU vendor */
+void acpi_processor_power_init_pdc(struct acpi_processor_power *pow,
+				   unsigned int cpu)
+{
+	struct cpuinfo_x86 *c = cpu_data + cpu;
+
+	pow->pdc = NULL;
+	if (c->x86_vendor == X86_VENDOR_INTEL)
+		acpi_processor_power_init_intel_pdc(pow);
+
+	return;
+}
+
+EXPORT_SYMBOL(acpi_processor_power_init_pdc);
+
+/*
+ * Initialize bm_flags based on the CPU cache properties
+ * On SMP it depends on cache configuration
+ * - When cache is not shared among all CPUs, we flush cache
+ *   before entering C3.
+ * - When cache is shared among all CPUs, we use bm_check
+ *   mechanism as in UP case
+ *
+ * This routine is called only after all the CPUs are online
+ */
+void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags,
+					unsigned int cpu)
+{
+	struct cpuinfo_x86 *c = cpu_data + cpu;
+
+	flags->bm_check = 0;
+	if (num_online_cpus() == 1)
+		flags->bm_check = 1;
+	else if (c->x86_vendor == X86_VENDOR_INTEL) {
+		/*
+		 * Today all CPUs that support C3 share cache.
+		 * TBD: This needs to look at cache shared map, once
+		 * multi-core detection patch makes to the base.
+		 */
+		flags->bm_check = 1;
+	}
+}
+
+EXPORT_SYMBOL(acpi_processor_power_init_bm_check);