diff options
Diffstat (limited to 'drivers/acpi/processor_perflib.c')
| -rw-r--r-- | drivers/acpi/processor_perflib.c | 50 |
1 files changed, 47 insertions, 3 deletions
diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c index 01e366d2b6fb..2cabadcc4d8c 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 |