linux/drivers/platform/x86/intel/tpmi_power_domains.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Mapping of TPMI power domains CPU mapping
 *
 * Copyright (c) 2024, Intel Corporation.
 */

#include <linux/bitfield.h>
#include <linux/cleanup.h>
#include <linux/cpuhotplug.h>
#include <linux/cpumask.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/hashtable.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/overflow.h>
#include <linux/slab.h>
#include <linux/topology.h>
#include <linux/types.h>

#include <asm/cpu_device_id.h>
#include <asm/intel-family.h>
#include <asm/msr.h>

#include "tpmi_power_domains.h"

#define MSR_PM_LOGICAL_ID …

/*
 * Struct of MSR 0x54
 * [15:11] PM_DOMAIN_ID
 * [10:3] MODULE_ID (aka IDI_AGENT_ID)
 * [2:0] LP_ID
 * For Atom:
 *   [2] Always 0
 *   [1:0] core ID within module
 * For Core
 *   [2:1] Always 0
 *   [0] thread ID
 */

#define LP_ID_MASK …
#define MODULE_ID_MASK …
#define PM_DOMAIN_ID_MASK …

/**
 * struct tpmi_cpu_info - Mapping information for a CPU
 * @hnode: Used to add mapping information to hash list
 * @linux_cpu:	Linux CPU number
 * @pkg_id: Package ID of this CPU
 * @punit_thread_id: Punit thread id of this CPU
 * @punit_core_id: Punit core id
 * @punit_domain_id: Power domain id from Punit
 *
 * Structure to store mapping information for a Linux CPU
 * to a Punit core, thread and power domain.
 */
struct tpmi_cpu_info { … };

static DEFINE_PER_CPU(struct tpmi_cpu_info, tpmi_cpu_info);

/* The dynamically assigned cpu hotplug state to free later */
static enum cpuhp_state tpmi_hp_state __read_mostly;

#define MAX_POWER_DOMAINS …

static cpumask_t *tpmi_power_domain_mask;

/* Lock to protect tpmi_power_domain_mask and tpmi_cpu_hash */
static DEFINE_MUTEX(tpmi_lock);

static const struct x86_cpu_id tpmi_cpu_ids[] = …;
MODULE_DEVICE_TABLE(x86cpu, tpmi_cpu_ids);

static DECLARE_HASHTABLE(tpmi_cpu_hash, 8);

static bool tpmi_domain_is_valid(struct tpmi_cpu_info *info)
{ … }

int tpmi_get_linux_cpu_number(int package_id, int domain_id, int punit_core_id)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

int tpmi_get_punit_core_number(int cpu_no)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

int tpmi_get_power_domain_id(int cpu_no)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

cpumask_t *tpmi_get_power_domain_mask(int cpu_no)
{ … }
EXPORT_SYMBOL_NS_GPL(…);

static int tpmi_get_logical_id(unsigned int cpu, struct tpmi_cpu_info *info)
{ … }

static int tpmi_cpu_online(unsigned int cpu)
{ … }

static int __init tpmi_init(void)
{ … }
module_init(…) …

static void __exit tpmi_exit(void)
{ … }
module_exit(…)

MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;