[linux-2.6-block.git] / drivers / acpi / processor_pdc.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2005 Intel Corporation
 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
 *
 *      Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
 *      - Added _PDC for platforms with Intel CPUs
 */

#define pr_fmt(fmt) "ACPI: " fmt

#include <linux/slab.h>
#include <linux/acpi.h>
#include <acpi/processor.h>

#include "internal.h"

static void acpi_set_pdc_bits(u32 *buf)
{
	buf[0] = ACPI_PDC_REVISION_ID;
	buf[1] = 1;
	buf[2] = 0;

	/* Twiddle arch-specific bits needed for _PDC */
	arch_acpi_set_proc_cap_bits(&buf[2]);
}

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;

	status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);

	if (ACPI_FAILURE(status))
		acpi_handle_debug(handle,
		    "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;
}

void __init acpi_early_processor_set_pdc(void)
{
	acpi_proc_quirk_mwait_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);
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
46ba51ea HG	2	/*
	3	* Copyright (C) 2005 Intel Corporation
	4	* Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
	5	*
	6	* Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
	7	* - Added _PDC for platforms with Intel CPUs
	8	*/
	9
	10	#define pr_fmt(fmt) "ACPI: " fmt
	11
46ba51ea HG	12	#include <linux/slab.h>
	13	#include <linux/acpi.h>
	14	#include <acpi/processor.h>
	15
	16	#include "internal.h"
	17
46ba51ea HG	18	static void acpi_set_pdc_bits(u32 *buf)
	19	{
	20	buf[0] = ACPI_PDC_REVISION_ID;
	21	buf[1] = 1;
b2eb3e67	22	buf[2] = 0;
46ba51ea	23
46ba51ea	24	/* Twiddle arch-specific bits needed for _PDC */
c5e4d05d	25	arch_acpi_set_proc_cap_bits(&buf[2]);
46ba51ea HG	26	}
	27
	28	static struct acpi_object_list *acpi_processor_alloc_pdc(void)
	29	{
	30	struct acpi_object_list *obj_list;
	31	union acpi_object *obj;
	32	u32 *buf;
	33
	34	/* allocate and initialize pdc. It will be used later. */
	35	obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
	36	if (!obj_list)
	37	goto out;
	38
	39	obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
	40	if (!obj) {
	41	kfree(obj_list);
	42	goto out;
	43	}
	44
	45	buf = kmalloc(12, GFP_KERNEL);
	46	if (!buf) {
	47	kfree(obj);
	48	kfree(obj_list);
	49	goto out;
	50	}
	51
	52	acpi_set_pdc_bits(buf);
	53
	54	obj->type = ACPI_TYPE_BUFFER;
	55	obj->buffer.length = 12;
	56	obj->buffer.pointer = (u8 *) buf;
	57	obj_list->count = 1;
	58	obj_list->pointer = obj;
	59
	60	return obj_list;
	61	out:
	62	pr_err("Memory allocation error\n");
	63	return NULL;
	64	}
	65
	66	/*
	67	* _PDC is required for a BIOS-OS handshake for most of the newer
	68	* ACPI processor features.
	69	*/
	70	static acpi_status
	71	acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
	72	{
	73	acpi_status status = AE_OK;
	74
46ba51ea HG	75	status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
	76
	77	if (ACPI_FAILURE(status))
52af99c3 RW	78	acpi_handle_debug(handle,
52af99c3 RW	79	"Could not evaluate _PDC, using legacy perf control\n");
46ba51ea HG	80
	81	return status;
	82	}
	83
	84	void acpi_processor_set_pdc(acpi_handle handle)
	85	{
	86	struct acpi_object_list *obj_list;
	87
	88	if (arch_has_acpi_pdc() == false)
	89	return;
	90
	91	obj_list = acpi_processor_alloc_pdc();
	92	if (!obj_list)
	93	return;
	94
	95	acpi_processor_eval_pdc(handle, obj_list);
	96
	97	kfree(obj_list->pointer->buffer.pointer);
	98	kfree(obj_list->pointer);
	99	kfree(obj_list);
	100	}
	101
	102	static acpi_status __init
	103	early_init_pdc(acpi_handle handle, u32 lvl, void context, void *rv)
	104	{
	105	if (processor_physically_present(handle) == false)
	106	return AE_OK;
	107
	108	acpi_processor_set_pdc(handle);
	109	return AE_OK;
	110	}
	111
46ba51ea HG	112	void __init acpi_early_processor_set_pdc(void)
46ba51ea HG	113	{
0a0e2ea6	114	acpi_proc_quirk_mwait_check();
46ba51ea HG	115
	116	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
	117	ACPI_UINT32_MAX,
	118	early_init_pdc, NULL, NULL, NULL);
	119	acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, early_init_pdc, NULL, NULL);
	120	}