diff options
Diffstat (limited to 'drivers/acpi/processor_pdc.c')
| -rw-r--r-- | drivers/acpi/processor_pdc.c | 206 | 
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/acpi/processor_pdc.c b/drivers/acpi/processor_pdc.c new file mode 100644 index 000000000000..e5dd80800930 --- /dev/null +++ b/drivers/acpi/processor_pdc.c @@ -0,0 +1,206 @@ +/* + * Copyright (C) 2005 Intel Corporation + * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. + * + *      Venkatesh Pallipadi <[email protected]> + *      - Added _PDC for platforms with Intel CPUs + */ + +#define pr_fmt(fmt) "ACPI: " fmt + +#include <linux/dmi.h> +#include <linux/slab.h> +#include <linux/acpi.h> +#include <acpi/processor.h> + +#include "internal.h" + +#define _COMPONENT              ACPI_PROCESSOR_COMPONENT +ACPI_MODULE_NAME("processor_pdc"); + +static bool __init processor_physically_present(acpi_handle handle) +{ +	int cpuid, type; +	u32 acpi_id; +	acpi_status status; +	acpi_object_type acpi_type; +	unsigned long long tmp; +	union acpi_object object = { 0 }; +	struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; + +	status = acpi_get_type(handle, &acpi_type); +	if (ACPI_FAILURE(status)) +		return false; + +	switch (acpi_type) { +	case ACPI_TYPE_PROCESSOR: +		status = acpi_evaluate_object(handle, NULL, NULL, &buffer); +		if (ACPI_FAILURE(status)) +			return false; +		acpi_id = object.processor.proc_id; +		break; +	case ACPI_TYPE_DEVICE: +		status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp); +		if (ACPI_FAILURE(status)) +			return false; +		acpi_id = tmp; +		break; +	default: +		return false; +	} + +	type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0; +	cpuid = acpi_get_cpuid(handle, type, acpi_id); + +	if (cpuid == -1) +		return false; + +	return true; +} + +static void acpi_set_pdc_bits(u32 *buf) +{ +	buf[0] = ACPI_PDC_REVISION_ID; +	buf[1] = 1; + +	/* Enable coordination with firmware's _TSD info */ +	buf[2] = ACPI_PDC_SMP_T_SWCOORD; + +	/* Twiddle arch-specific bits needed for _PDC */ +	arch_acpi_set_pdc_bits(buf); +} + +static struct acpi_object_list *acpi_processor_alloc_pdc(void) +{ +	struct acpi_object_list *obj_list; +	union acpi_object *obj; +	u32 *buf; + +	/* allocate and initialize pdc. It will be used later. */ +	obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL); +	if (!obj_list) +		goto out; + +	obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL); +	if (!obj) { +		kfree(obj_list); +		goto out; +	} + +	buf = kmalloc(12, GFP_KERNEL); +	if (!buf) { +		kfree(obj); +		kfree(obj_list); +		goto out; +	} + +	acpi_set_pdc_bits(buf); + +	obj->type = ACPI_TYPE_BUFFER; +	obj->buffer.length = 12; +	obj->buffer.pointer = (u8 *) buf; +	obj_list->count = 1; +	obj_list->pointer = obj; + +	return obj_list; +out: +	pr_err("Memory allocation error\n"); +	return NULL; +} + +/* + * _PDC is required for a BIOS-OS handshake for most of the newer + * ACPI processor features. + */ +static acpi_status +acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in) +{ +	acpi_status status = AE_OK; + +	if (boot_option_idle_override == IDLE_NOMWAIT) { +		/* +		 * If mwait is disabled for CPU C-states, the C2C3_FFH access +		 * mode will be disabled in the parameter of _PDC object. +		 * Of course C1_FFH access mode will also be disabled. +		 */ +		union acpi_object *obj; +		u32 *buffer = NULL; + +		obj = pdc_in->pointer; +		buffer = (u32 *)(obj->buffer.pointer); +		buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH); + +	} +	status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL); + +	if (ACPI_FAILURE(status)) +		ACPI_DEBUG_PRINT((ACPI_DB_INFO, +		    "Could not evaluate _PDC, using legacy perf. control.\n")); + +	return status; +} + +void acpi_processor_set_pdc(acpi_handle handle) +{ +	struct acpi_object_list *obj_list; + +	if (arch_has_acpi_pdc() == false) +		return; + +	obj_list = acpi_processor_alloc_pdc(); +	if (!obj_list) +		return; + +	acpi_processor_eval_pdc(handle, obj_list); + +	kfree(obj_list->pointer->buffer.pointer); +	kfree(obj_list->pointer); +	kfree(obj_list); +} + +static acpi_status __init +early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv) +{ +	if (processor_physically_present(handle) == false) +		return AE_OK; + +	acpi_processor_set_pdc(handle); +	return AE_OK; +} + +static int __init set_no_mwait(const struct dmi_system_id *id) +{ +	pr_notice("%s detected - disabling mwait for CPU C-states\n", +		  id->ident); +	boot_option_idle_override = IDLE_NOMWAIT; +	return 0; +} + +static struct dmi_system_id processor_idle_dmi_table[] __initdata = { +	{ +	set_no_mwait, "Extensa 5220", { +	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"), +	DMI_MATCH(DMI_SYS_VENDOR, "Acer"), +	DMI_MATCH(DMI_PRODUCT_VERSION, "0100"), +	DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL}, +	{}, +}; + +static void __init processor_dmi_check(void) +{ +	/* +	 * Check whether the system is DMI table. If yes, OSPM +	 * should not use mwait for CPU-states. +	 */ +	dmi_check_system(processor_idle_dmi_table); +} + +void __init acpi_early_processor_set_pdc(void) +{ +	processor_dmi_check(); + +	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, +			    ACPI_UINT32_MAX, +			    early_init_pdc, NULL, NULL, NULL); +	acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, early_init_pdc, NULL, NULL); +}  |