diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/processor_throttling.c | 66 |
1 files changed, 36 insertions, 30 deletions
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index 5fa8ac1c0c8..20d82f55ce5 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -478,6 +478,40 @@ static int acpi_processor_get_throttling(struct acpi_processor *pr) return pr->throttling.acpi_processor_get_throttling(pr); } +static int acpi_processor_get_fadt_info(struct acpi_processor *pr) +{ + int i, step; + + if (!pr->throttling.address) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n")); + return -EINVAL; + } else if (!pr->throttling.duty_width) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n")); + return -EINVAL; + } + /* TBD: Support duty_cycle values that span bit 4. */ + else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) { + printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n"); + return -EINVAL; + } + + pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width; + + /* + * Compute state values. Note that throttling displays a linear power + * performance relationship (at 50% performance the CPU will consume + * 50% power). Values are in 1/10th of a percent to preserve accuracy. + */ + + step = (1000 / pr->throttling.state_count); + + for (i = 0; i < pr->throttling.state_count; i++) { + pr->throttling.states[i].performance = 1000 - step * i; + pr->throttling.states[i].power = 1000 - step * i; + } + return 0; +} + static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr, int state) { @@ -591,8 +625,6 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state) int acpi_processor_get_throttling_info(struct acpi_processor *pr) { int result = 0; - int step = 0; - int i = 0; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n", @@ -611,6 +643,8 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr) acpi_processor_get_throttling_states(pr) || acpi_processor_get_platform_limit(pr)) { + if (acpi_processor_get_fadt_info(pr)) + return 0; pr->throttling.acpi_processor_get_throttling = &acpi_processor_get_throttling_fadt; pr->throttling.acpi_processor_set_throttling = @@ -624,19 +658,6 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr) acpi_processor_get_tsd(pr); - if (!pr->throttling.address) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n")); - return 0; - } else if (!pr->throttling.duty_width) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n")); - return 0; - } - /* TBD: Support duty_cycle values that span bit 4. */ - else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) { - printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n"); - return 0; - } - /* * PIIX4 Errata: We don't support throttling on the original PIIX4. * This shouldn't be an issue as few (if any) mobile systems ever @@ -648,21 +669,6 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr) return 0; } - pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width; - - /* - * Compute state values. Note that throttling displays a linear power/ - * performance relationship (at 50% performance the CPU will consume - * 50% power). Values are in 1/10th of a percent to preserve accuracy. - */ - - step = (1000 / pr->throttling.state_count); - - for (i = 0; i < pr->throttling.state_count; i++) { - pr->throttling.states[i].performance = step * i; - pr->throttling.states[i].power = step * i; - } - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n", pr->throttling.state_count)); |