summaryrefslogtreecommitdiff
path: root/drivers/acpi/processor_pdc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/acpi/processor_pdc.c')
-rw-r--r--drivers/acpi/processor_pdc.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/drivers/acpi/processor_pdc.c b/drivers/acpi/processor_pdc.c
new file mode 100644
index 000000000000..30e4dc0cdf30
--- /dev/null
+++ b/drivers/acpi/processor_pdc.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2005 Intel Corporation
+ * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
+ *
+ * Alex Chiang <achiang@hp.com>
+ * - Unified x86/ia64 implementations
+ * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
+ * - Added _PDC for platforms with Intel CPUs
+ */
+#include <linux/dmi.h>
+
+#include <acpi/acpi_drivers.h>
+#include <acpi/processor.h>
+
+#include "internal.h"
+
+#define PREFIX "ACPI: "
+#define _COMPONENT ACPI_PROCESSOR_COMPONENT
+ACPI_MODULE_NAME("processor_pdc");
+
+static int set_no_mwait(const struct dmi_system_id *id)
+{
+ printk(KERN_NOTICE PREFIX "%s detected - "
+ "disabling mwait for CPU C-states\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},
+ {},
+};
+
+static void acpi_set_pdc_bits(u32 *buf)
+{
+ buf[0] = ACPI_PDC_REVISION_ID;
+ buf[1] = 1;
+
+ /* Enable coordination with firmware's _TSD info */
+ buf[2] = ACPI_PDC_SMP_T_SWCOORD;
+
+ /* Twiddle arch-specific bits needed for _PDC */
+ arch_acpi_set_pdc_bits(buf);
+}
+
+static struct acpi_object_list *acpi_processor_alloc_pdc(void)
+{
+ 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 NULL;
+ }
+
+ obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
+ if (!obj) {
+ printk(KERN_ERR "Memory allocation error\n");
+ kfree(obj_list);
+ return NULL;
+ }
+
+ buf = kmalloc(12, GFP_KERNEL);
+ if (!buf) {
+ printk(KERN_ERR "Memory allocation error\n");
+ kfree(obj);
+ kfree(obj_list);
+ return NULL;
+ }
+
+ acpi_set_pdc_bits(buf);
+
+ obj->type = ACPI_TYPE_BUFFER;
+ obj->buffer.length = 12;
+ obj->buffer.pointer = (u8 *) buf;
+ obj_list->count = 1;
+ obj_list->pointer = obj;
+
+ return obj_list;
+}
+
+/*
+ * _PDC is required for a BIOS-OS handshake for most of the newer
+ * ACPI processor features.
+ */
+static int
+acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
+{
+ acpi_status status = AE_OK;
+
+ if (idle_nomwait) {
+ /*
+ * If mwait is disabled for CPU C-states, the C2C3_FFH access
+ * mode will be disabled in the parameter of _PDC object.
+ * Of course C1_FFH access mode will also be disabled.
+ */
+ union acpi_object *obj;
+ u32 *buffer = NULL;
+
+ obj = pdc_in->pointer;
+ buffer = (u32 *)(obj->buffer.pointer);
+ buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
+
+ }
+ status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
+
+ if (ACPI_FAILURE(status))
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Could not evaluate _PDC, using legacy perf. control.\n"));
+
+ return status;
+}
+
+void acpi_processor_set_pdc(acpi_handle handle)
+{
+ struct acpi_object_list *obj_list;
+
+ if (arch_has_acpi_pdc() == false)
+ return;
+
+ obj_list = acpi_processor_alloc_pdc();
+ if (!obj_list)
+ return;
+
+ acpi_processor_eval_pdc(handle, obj_list);
+
+ kfree(obj_list->pointer->buffer.pointer);
+ kfree(obj_list->pointer);
+ kfree(obj_list);
+}
+EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
+
+static acpi_status
+early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+ acpi_processor_set_pdc(handle);
+ return AE_OK;
+}
+
+void acpi_early_processor_set_pdc(void)
+{
+ /*
+ * Check whether the system is DMI table. If yes, OSPM
+ * should not use mwait for CPU-states.
+ */
+ dmi_check_system(processor_idle_dmi_table);
+
+ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
+ ACPI_UINT32_MAX,
+ early_init_pdc, NULL, NULL, NULL);
+}