diff options
| -rw-r--r-- | drivers/acpi/processor_driver.c | 1 | ||||
| -rw-r--r-- | drivers/acpi/processor_perflib.c | 22 | ||||
| -rw-r--r-- | include/acpi/processor.h | 1 |
3 files changed, 24 insertions, 0 deletions
diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index 0034ede38710..e6920d0aca53 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -497,6 +497,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device) #ifdef CONFIG_CPU_FREQ acpi_processor_ppc_has_changed(pr, 0); + acpi_processor_load_module(pr); #endif acpi_processor_get_throttling_info(pr); acpi_processor_get_limit_info(pr); diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c index 85b32376dad7..0af48a8554cd 100644 --- a/drivers/acpi/processor_perflib.c +++ b/drivers/acpi/processor_perflib.c @@ -240,6 +240,28 @@ void acpi_processor_ppc_exit(void) acpi_processor_ppc_status &= ~PPC_REGISTERED; } +/* + * Do a quick check if the systems looks like it should use ACPI + * cpufreq. We look at a _PCT method being available, but don't + * do a whole lot of sanity checks. + */ +void acpi_processor_load_module(struct acpi_processor *pr) +{ + static int requested; + acpi_status status = 0; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + + if (!arch_has_acpi_pdc() || requested) + return; + status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer); + if (!ACPI_FAILURE(status)) { + printk(KERN_INFO PREFIX "Requesting acpi_cpufreq\n"); + request_module_nowait("acpi_cpufreq"); + requested = 1; + } + kfree(buffer.pointer); +} + static int acpi_processor_get_performance_control(struct acpi_processor *pr) { int result = 0; diff --git a/include/acpi/processor.h b/include/acpi/processor.h index 610f6fb1bbc2..da57fdcc57d2 100644 --- a/include/acpi/processor.h +++ b/include/acpi/processor.h @@ -224,6 +224,7 @@ struct acpi_processor_errata { } piix4; }; +extern void acpi_processor_load_module(struct acpi_processor *pr); extern int acpi_processor_preregister_performance(struct acpi_processor_performance __percpu *performance); |