summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/processor_perflib.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/acpi/processor_perflib.c')
-rw-r--r--drivers/acpi/processor_perflib.c56
1 files changed, 52 insertions, 4 deletions
diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c
index 01e366d2b6f..a959f6a0750 100644
--- a/drivers/acpi/processor_perflib.c
+++ b/drivers/acpi/processor_perflib.c
@@ -152,15 +152,59 @@ static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
return 0;
}
-int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
+#define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
+/*
+ * acpi_processor_ppc_ost: Notify firmware the _PPC evaluation status
+ * @handle: ACPI processor handle
+ * @status: the status code of _PPC evaluation
+ * 0: success. OSPM is now using the performance state specificed.
+ * 1: failure. OSPM has not changed the number of P-states in use
+ */
+static void acpi_processor_ppc_ost(acpi_handle handle, int status)
+{
+ union acpi_object params[2] = {
+ {.type = ACPI_TYPE_INTEGER,},
+ {.type = ACPI_TYPE_INTEGER,},
+ };
+ struct acpi_object_list arg_list = {2, params};
+ acpi_handle temp;
+
+ params[0].integer.value = ACPI_PROCESSOR_NOTIFY_PERFORMANCE;
+ params[1].integer.value = status;
+
+ /* when there is no _OST , skip it */
+ if (ACPI_FAILURE(acpi_get_handle(handle, "_OST", &temp)))
+ return;
+
+ acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
+ return;
+}
+
+int acpi_processor_ppc_has_changed(struct acpi_processor *pr, int event_flag)
{
int ret;
- if (ignore_ppc)
+ if (ignore_ppc) {
+ /*
+ * Only when it is notification event, the _OST object
+ * will be evaluated. Otherwise it is skipped.
+ */
+ if (event_flag)
+ acpi_processor_ppc_ost(pr->handle, 1);
return 0;
+ }
ret = acpi_processor_get_platform_limit(pr);
-
+ /*
+ * Only when it is notification event, the _OST object
+ * will be evaluated. Otherwise it is skipped.
+ */
+ if (event_flag) {
+ if (ret < 0)
+ acpi_processor_ppc_ost(pr->handle, 1);
+ else
+ acpi_processor_ppc_ost(pr->handle, 0);
+ }
if (ret < 0)
return (ret);
else
@@ -369,7 +413,11 @@ static int acpi_processor_get_performance_info(struct acpi_processor *pr)
if (result)
goto update_bios;
- return 0;
+ /* We need to call _PPC once when cpufreq starts */
+ if (ignore_ppc != 1)
+ result = acpi_processor_get_platform_limit(pr);
+
+ return result;
/*
* Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that