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ACPI: If _TSS exists, do not access FADT.duty_width 

Factor out legacy FADT.duty_width code
and run it only in the non _TSS case.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Zhao Yakui 2007-11-15 17:02:03 +08:00 committed by Len Brown
parent 49fbabf56d
commit 22cc50199d
1 changed files with 36 additions and 30 deletions
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66
drivers/acpi/processor_throttling.c
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@ -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));