Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 22cc5019 authored by Zhao Yakui's avatar Zhao Yakui Committed by Len Brown
Browse files

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: default avatarZhao Yakui <yakui.zhao@intel.com>
Signed-off-by: default avatarLi Shaohua <shaohua.li@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 49fbabf5

drivers/acpi/processor_throttling.c

+36 −30
Original line number Diff line number Diff line
@@ -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));