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authorVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>2005-04-15 15:07:10 -0400
committerLen Brown <len.brown@intel.com>2005-07-12 00:14:36 -0400
commit02df8b9385c21fdba165bd380f60eca1d3b0578b (patch)
tree988ad0e0ca73a40993fb1458d5cd19f90f922b31 /arch/i386/kernel/acpi
parent17e9c78a75ce9eacd61200f9e1f1924012e28846 (diff)
[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>
Diffstat (limited to 'arch/i386/kernel/acpi')
-rw-r--r--arch/i386/kernel/acpi/Makefile4
-rw-r--r--arch/i386/kernel/acpi/cstate.c103
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);